Space Geodesy and Earth System (SGES 2012) Aug 18-25, 2012, Shanghai, China

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International Symposium & Summer School on Space Geodesy and Earth System (SGES 2012) Aug 18-25, 2012, Shanghai, China http://www.shao.ac.cn/meetings; http://www.shao.ac.cn/schools

Venue: 3rd floor of Astronomical Building Shanghai Astronomical Observatory, Chinese Academy of Sciences

International Symposium on

Space Geodesy and Earth Sytem (SGES2012) August 18-21, 2011, Shanghai, China http://www.shao.ac.cn/meetings

Contact Information: Email: [email protected]; [email protected] Emergency Phone: 13167075822 Police: 110; Ambulance: 120

Venue: 3rd floor, Astronomical Building Shanghai Astronomical Observatory, Chinese Academy of Sciences 80 Nandan Road, Shanghai 200030, China

Available WIFI at the workshop with the password at conference hall doors

Sponsors • International Association of Geodesy (IAG) Commission 1, 3, 4 • International Association of Geodesy Sub-Commission 2.6 • Asia-Pacific Space Geodynamics Program (APSG) • Global Geodetic Observing System (GGOS) • Shanghai Astronomical Observatory (SHAO), CAS

Scientific Organizing Committee (SOC)

• Zuheir Altamimi (IGN, France) • Jeff T. Freymueller (Uni. Alaska, USA) • Richard S. Gross (JPL, NASA, USA) • Manabu Hashimoto (Kyoto Uni., Japan) • Shuanggen Jin (SHAO, CAS, China) (Chair) • Roland Klees (TUDelft, Netherlands) • Christopher Kotsakis (AUTH, Greece) • Michael Pearlman (Harvard-CFA, USA) • Wenke Sun (Grad. Uni. of CAS, China) • Harald Schuh (TU-Vienna, Austria) • Tonie van Dam (Univ. Luxembourg) • Jens Wickert (GFZ Potsdam, Germany) • Shimon Wdowinski (Univ. Miami, USA)

Local Organizing Committee (LOC)

• Liang Chang (SHAO) • Wenli Dong (SHAO) • Guiping Feng (SHAO) • Shuanggen Jin (SHAO) (Chair) • Xueqing Xu (SHAO) • Yansong Xue (SHAO) • Xinggang Zhang (SHAO)

Top ics

• Space geodetic techniques and reference frame (Zuheir Altamimi, Michael Pearlman) • GNSS atmo-/ionospheric sounding and Climatology (Jens Wickert, Tom Yunck) • Satellite gravimetry, gravity field and geoid (Roland Klees, Christopher Kotsakis) • SAR/InSAR/LiDAR and Remote Sensing Applications (Xiaoli Ding, Manabu Hashimoto) • Sea level change, ocean tides and ocean circulation (Jens Schroeter, Shuanggen Jin) • Ice/snow melting and land hydrological cycle (Tonie van Dam, Shimon Wdowinski) • Earth rotation, geodynamics and Earth system coupling (Richard Gross, Harald Schuh) • Active tectonic deformation and earthquake geodesy (Jeff. Freymueller, Wenke Sun)

Special Issue at Journal of Geodynamics:

Special issue of Journal of Geodynamics on “Earth System Observing and Modelling from Space Geodesy” via http://ees.elsevier.com/geod. To ensure that all manuscripts are correctly identified for inclusion into the special issue, authors must select "SI: Geodetic Earth System" when they reach the "Article Type" step in the submission process.

Dear All Participants

Mass redistribution and transport in the Earth system, including the atmosphere, hydrosphere, lithosphere,

cryosphere and the interior of the solid Earth affect the Earth's shape, gravity field and rotation (the three

pillars of geodesy). Space geodetic techniques, including VLBI, SLR, DORIS, GNSS, InSAR, LiDAR,

ICESat, satellite radar and laser altimetry, satellite gravimetry (particularly CHAMP/GRACE/GOCE) and

GNSS Reflectometry & Radio Occultation, are capable of measuring and monitoring such small changes with high accuracy and spatial-temporal resolution. These provide a unique opportunity to investigate mass transport associated with geodynamics, natural hazards, and climate change, and to better understand these processes and their interaction within the Earth system.

The International Symposium on “Space Geodesy and Earth System” will be a forum for assessing current technological capabilities and presenting recent results of space geodetic observations and understanding the physical processes and coupling in the Earth system, and future impacts on climate. Topics include data retrieval of space geodetic techniques, reference frame, atmospheric-ionospheric sounding and disturbance, gravity field, crustal deformation and earthquake geodesy, GIA, Earth rotation, hydrological cycle, ocean circulation, sea level change, and ice sheet mass balance as well as their coupling in the Earth system.

On behalf of the Organizing Committee, we are pleased to invite you to attend the International Symposium on Space Geodesy and Earth System (SGES2012), August 18-21, 2011, Shanghai, China. For any questions, please feel free to contact LOC at http://www.shao.ac.cn/meetings

Sincerely yours

Prof. Shuanggen Jin On behalf of the Organizing Committee,

Astronomical Building of Shanghai Astronomical Observatory, CAS

25m radio telescope, 1.56m reflector, SLR, GPS etc. at SHAO

Shuhua Ye is an Academician of Chinese Academy of Sciences. She was Director of Shanghai Astronomical Observatory in 1981-1993 and the vice president of the International Astronomical Union in 1988-1994. She is vice-president of the Chinese Association for Science and Technology, and member of the Standing Committee of the National Congress of China. In the 1990’s, she has been the chief scientist for a major state basic research project “Investigation on Recent Crustal Motion and Geodynamics”. As an extension of this project, in 1994, she initiated an international project “Asia-Pacific Space Geodynamics” as chairman of the

Management Board, endorsed by the International Association of Geodesy.

Yaolin Shi is an academician of the Chinese Academy of Sciences and a professor at the Graduate University of Chinese Academy of Sciences. He graduated from the University of Science and Technology of China in 1966 and obtained a doctor's degree from the University of California, Berkley in 1986. He, considered the deformation, interstitial fluid and complex coupling effect of heat transfer, and achieved much in the field of geodynamics quantitative simulation. As a result, he initiated the research orientation of geothermal tectonic science. While conducting research on the Qinghai-Tibet plateau and the Himalayans, he examined the qualitative illumination of aerial geothermal features and formation mechanisms.

Harald Schuh has been working in the field of Very Long Baseline Interferometry (VLBI) modelling and analysis for almost 30 years. He has achieved a deep understanding in the complex dynamics of the Earth's motion with respect to the distant quasar system and the related processes covering Earth orientation, geophysics and astrophysics. Moreover, he used VLBI for the realization of a kinematic inertial reference system and has pushed the steady improvement of VLBI measurement technology and analysis. He is a well-known contributor to the geodesy community and has been vice-President of the IAG (International

Association of Geodesy).

Zuheir Altamimi is a Research Director at the Institut National de l’Information Géographique et Forestière (IGN), France. His principal research focuses are space geodesy, theory and realization of terrestrial reference systems. He is head of the terrestrial reference systems research group at the Laboratoire de Recherche en Géodésie of the IGN. He acted as President of Commission 1 (Reference Frames) of the International Association of Geodesy (2007-2011). He is member of the International Earth Rotation and Reference Systems Service (IERS) Directing Board and of the Governing Board of the International GNSS Service (IGS). He is head and principle scientist of the International Terrestrial Reference System (ITRS) Product Center of the IERS. His honors include Prix de Cartographie (1996) and d’Abbadie (2011) of the French Academy of Sciences and Chevalier dans l’Ordre des Palmes Académiques (2006). He is a fellow of the International Association of Geodesy. He received his Ph.D. in space geodesy from Paris Observatory, and his habilitation (2nd doctorate) from Paris University VI.

Richard S. Gross is a Principle Scientist and Group Supervisor at NASA Jet Propulsion Laboratory (JPL), Caltech, USA. He obtained the B.S. at Purdue University in 1975 and Ph.D. at University of Colorado in 1982. His main interests are Earth rotation variations, time variable gravity and ocean-solid Earth interactions. He has received several awards, e.g., NASA Exceptional Scientific Achievement Medal: Chandler wobble, 2001 and NASA Group Achievement Awards in 1996-1999. He is President of International Association of Geodesy (IAG) Commission 3 “Earth Rotation and Geodynamics” (2011-2015).

Tonie M. Van Dam is an associate professor at University of Luxembourg, Luxembourg. Her major areas are modeling environmental loading effects on geodetic coordinate time series and the International Terrestrial Reference Frame (ITRF); applying time-variable gravity as a constraint on geodetic coordinate time series and the ITRF; climate and climate change; radiative transfer; monitoring and modeling individual sources of mass distribution and transport in the Earth system by means of satellites. She has over 50 publications. She was a board member of International Earth Rotation and Reference Frame Service (IERS) and president of International Association of Geodesy (IAG)’s Commission 1 “Reference Frame”.

Shimon Wdowinski is a research associate professor at the Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, where he teaches and researches geology and geophysics. His work has focused on the development and usage of space geodetic techniques that can detect very precisely small movements of the Earth’s surface. He successfully applied these technologies to study natural hazards and environmental phenomena, such as earthquakes, landslides, and wetland surface flow. He received a B.Sc in Earth Sciences (1983) and M.Sc. in Geology (1985) from the Hebrew University (Jerusalem, Israel) and an M.S. in Engineering Sciences (1987) and Ph.D. in Geophysics (1990) from Harvard University. Before resuming a faculty position at Tel Aviv University (1994-2001), he conducted a post-doctorate research at Scripps Institute of Oceanography, UCSD (1990-1993). He joined the University of Miami in 2001.

Jens Wickert, born 1963, graduated in physics from the Technical University Dresden and obtained his doctor’s degree externally in 2002 from Karl-Franzens-University Graz in Geophysics/Meteorology. He worked for a number of years in atmospheric research for the German Weather Service, the Alfred-Wegener-Institute for Polar and Marine Research at Bremerhaven and for the German Aerospace Center. Currently he is acting head of section 1.1 “GPS/Galileo Earth Observation” at the German Research Center for Geosciences GFZ at Potsdam. Dr. Wickert is involved in many national and international satellite missions and research projects predominantly in a leading position. He is Author/Co—Author of numerous publications related to GNSS Earth Observation and GNSS Remote Sensing in international leading journals.

Wenke Sun is Professor, Director of College of Earth Sciences and Director of the Key Laboratory of Computational Geodynamics, Chinese Academy of Sciences. His main interesting is Dislocation theory for a spherical earth model, Gravity observation and interpretation, Satellite gravity mission GRACE and its application, and Tibetan geodynamic changes. He received the B.Sc at Wuhan Technical Univ. of Surv. and Map. in 1982, M.Sc at State Seismological Bureau in 1984, and Ph.D at ERI, University of Tokyo, Tokyo, Japan in 1994.

Jeff T. Freymueller is Professor at the Geophysical Institute of University of Alaska Fairbanks, USA. He received a B.Sc degree from the California Institute of Technology in 1985, and MS and PhD degrees from the University of South Carolina in 1988 and 1991 respectively. Following his PhD, he worked as a Postdoctoral Researcher at Stanford University for three and a half years. His interests include understanding active Earth processes, understanding and improving the tools to measure active Earth processes, active crustal deformation processes, and kinetics and dynamics of active processes that shape the Earth.

Roland Klees is a Professor in Physical Geodesy, Delft University of Technology, Netherlands. He received degree of a Dr.-Ing. in 1991 on “Boundary element methods for the fixed gravimetric boundary value problem”; Senior Researcher, University of Karlsruhe (1991-1993); Habilitation in Geodesy, University of Karlsruhe 1993; Head of the Department System Theory and Modeling (GFZ Potsdam) (1993-1994); since 1994 Professor in Physical Geodesy, Delft University of Technology; Head of the Physical, Geometric and Space Geodesy group, Delft University of Technology (1994-2003); since 2003 Head of the Physical and Space

Geodesy group, Delft University of Technology, 1997-2006.

Michael Pearlman is a Program Manager at the Harvard-Smithsonian Center for Astrophysics in Cambridge Massachusetts in the US. He has been working in Space Geodesy, primarily laser ranging to satellites, in NASA programs since 1968. He is currently the Director of the Central Bureau of the International Laser Ranging Service (ILRS) and the Director of the Bureau for Networks and Communication in the Global Geodetic Observing System (GGOS). He is part of the team working on the NASA Space Geodesy Program.

Shuanggen Jin is a Professor and Group Head at the Shanghai Astronomical Observatory, CAS. His main interests include Satellite Navigation & GNSS Sensing, Remote Sensing & Climate Change, and Space/Planetary Sensing & Dynamics. He has over 70 peer-reviewed journal papers in JGR, IEEE, J. Geodesy etc., 3 books and 10 books chapters and more than 100 conference papers. He has been President of the IAG Sub-Commission 2.6 (2011-2015), Editor of J. Geod. Sci. (2010- ) and Editor-in-Chief of Int. J. Geosci. (2010- ). He has received Special Prize of the Korea Astronomy and Space Science Institute (2006), CAS’s One-Hundred Talents Program (2010) and Fellow of International Association of Geodesy (IAG) (2011). 8

Content 1．Symposium Program Schedule ...... …………………11 2．Summer School Schedule ...... …………………17 3．Abstracts ...... …………………19 Pearlman, et al., GGOS Ground Based Space Geodesy Networks Required to Improve the Reference Frame19 Altamimi, Z., Recent Results from ITRF Combination Activities ...... 20 Sun, H., Observations of the Superconducting Gravimeters and its Application in Geodynamics of the Earth's Interior ...... 20 Liu, Z.Z., A New Approach to Evaluating the Absolute Accuracy of Multiple Water Vapor Observation Techniques ………………………………………………………………………………………………….….20 Ma, Y., Third Pole Environment (TPE)Programme: A new base for the study of atmosphere-land interaction over the Tibetan Plateau and surrounding areas ...... 21 Wdowinski, et al., Rising of the lowest place on Earth due to Dead Sea water-level drop: Evidence from SAR interferometry and GPS ...... 22 Schuh, H., Geodetic Very Long Baseline Interferometry (VLBI) and its future perspectives ...... 23 Chen, P., CPM-CGCS2000 Plate Motion Model ...... 23 Delva, P., A reference frame for geophysics and relativistic geodesy ...... 24 Tatevyan, S. et al., Results of the GLONASS measurements analysis...... 24 Chen, Q., Separation of modulated seasonal signals from GPS time series with singular spectrum analysis ... 25 Fernandes, R., Present-day kinematics of Singapore: effects on the reference frame realization ...... 25 Gross, R., The Rotational and Gravitational Signature of Recent Great Earthquakes ...... 26 Böhm, S., et al., Zonal tidal variations in UT1 derived within a VLBI global solution ...... 26 Kirschner, S. et al., Estimation of Earth parameters of polar motion - Comparison of two approaches ...... 27 Nilsson, T. et al., Correspondence between free core nutation and nearly diurnal free wobble estimated from VLBI and ring laser gyroscopes ...... 27 Naqvi, N., GNSS Phase Based Attitude Determination of Satellite: The Problem Revisited ...... 28 Hu, H. et al., Cycle-slip Detection in PPP based on Empirical Mode Decomposition ...... 28 Ebauer, K. et al., On the use of BLITS satellites for precise positioning...... 29 Duan, X., Performance Analysis on Different Combined Integrity Schemes of Multi-constellation Navigation29 Wang, W. et al., Research and Design on the Observation System of Navigation Constellation Inter-Satellite Links……………………………………………………………………………………………………………30 Na, S., Polar wander and Response to Earthquake of An Ideal Viscoelastic Earth ...... 30 Sun, J., Relevance Analysis between Mass Redistribution and Length of DayVariationswithin Earth System 31 Liu, Z., Symmetry-Relationship Database Management System ...... 31 Wei, E. et al., On the Interconnections of Different Coordinate and Time Systems Based on SOFA ...... 32 Wei, E., Estimation of High-frequency ERPs with GPS Observations ...... 32 Wu, Z., ‘Repeating earthquakes’ as measures of deformation in deep: empirical and theoretical investigation 33 Zhang, K. et al., Shape, Winds and Gravity of rapidly rotating Jupiter ...... 33 Novak, P., Evaluation of potential fields generated by Earth’s mass components ...... 34 Hill, E. et al., Spatial variations in sea level in the near field of melting ice: Effects of Alaskan glacier melting using a spatially realistic load model ...... 34 Albertella, A. et al., Ocean circulation in Southern Ocean from GOCE gravity model ...... 35 Wei, E. et al., On the kinematic positioning of a lunar rover with SBI technology ...... 35 Hooper, A. et al., High-resolution constraints on the response to ice load changes in the Antarctic Peninsula and Iceland, using radar interferometry ...... 35 Hashimoto, M., Ground Deformation in the Kyoto Basin and Osaka Plain Detected with SAR Interferometry36 Li, Z. et al., Indexing Method for LIDAR Points Cloud Data Based on Spatial Characteristics ...... 37

Muhuri, et al., UNSUPERVISED CLASSIFICATION OF DUAL BAND POLARIMETRIC SAR IMAGE USING NON-GAUSSIAN STATISTICAL MODELS ...... 37 Wu, X. et al., Bare Surface Scattering Properties Study in order for GNSS-R Applications ...... 38 Li, Z. et al., Correcting Unmodeled Periodical Ocean Tidal Loading at the Observation Level and Its Impact on Continuous GPS Coordinate Time Series ...... 39 Zhou, F., Study on Seasonal Variations Derived from Vertical Component of GPS Site Position Time Series 40 Du, X. et al., Change Detection about Coal Fire Districts by Interpreting with Thermal Remote Sensing ...... 41 Yi, W., A gravity field model from GOCE and Combination with GRACE ...... 41 Jin, S., G.. Feng, Melting of ice-sheet in the Tibet confirmed by satellite gravity measurement ...... 42 Wei, E. et al., On the Chinese Spaceflight TT&C Network for Tiangong-1…………………………………42 Huang, et al., The average acceleration approach applied to gravity coefficients recovery based on GOCE orbits ...... 43 Andam, A. et al.,Spatio-Temporal Variations of Water Storage, Precipitation and Evapotranspiration in the Vol ta River Basin ...... 43 Zhang, S., Statistical analysis of ionospheric TEC day-to-day variability ...... 43 Chen, J. et al., Diurnal Variation of Ground-based GPS-PWV under Different Solar Radiation Intensity in Chengdu Area ...... 44 Kaplon, J. et al., NEAR - REAL TIME ZTD MODEL FOR THE AREA OF POLAND ...... 45 Rundle, J., Numerical Simulations of Earthquake Fault Systems for Earthquake Physics, Forecasting, and Geodetic Data Analysis ...... 45 Sun, W. et al., Co-seismic Deflection Change of the Vertical Caused by the 2011 Tohoku-Oki Earthquake,……………………………………………………………………………………………………..46 Talich, M., Creation of strain maps from velocity field of deformation by on-line tools ...... 47 Zhu, B. et al., Coriolis-induced state-rate law and strain energy function in coseismic rupture ...... 47 Xu, C. et al., Present-day 3D crustal movement in the Qinghai-Tibetan Plateau from GPS data ...... 48 Tsang, L. et al., Inversion for the spatial distribution of afterslip following the 2007 Mw 8.4 Bengkulu earthquake in Sumatra, using a principal component analysis-based inversion method (PCAIM) of SuGAR GPS time-series data ...... 50 Feng, L. et al., Moderate-to-Large Earthquakes at the Sumatran subduction zone observed by the Sumatra GPS Array (SuGAr) ...... 51 Na, S. et al., Ocean Tide and Ocean Loading Models of the Yellow Sea ...... 52 Tang, X., Support Vector Machine Aided Extended Kalman Filtering Algorithms for GPS/INS Integrated Navigation ...... 52 Na, S. et al., Seasonal variability of Global Earthquake Occurrence ...... 52 Abedini, A. et al., Analysis of tides in Shahid Rajaee Port buoys using integrated least squares harmonic constituent and Fourier series in simplified Geo-database ...... 53 Zhu, J., Overview on modern surveying adjustment and theory of data processing ...... 54 Wei, E. et al., On the Search Algorithm of Independent baselines for GNSS Data Processing ...... 54 Hassan, A. et al., GRACE Detection of water storage variation in Africa and its response to climate events .. 54 Qiu, Q. et al., Tsunami modeling of a historical giant submarine landslide offshore of Brunei ...... 55 Najibi, N. et al., Snow depth and ice thickness in North Canada retrieved from GPS code-phase difference multipath signals ...... 55 Panda, S. et al., Response of ionospheric total electron content to super-intense geomagnetic storms: An investigation with dual frequency GPS observation data at IIT Bombay, Mumbai, India…………………………………………………………………………………………………………….56

4．Participants List ...... …………………58

1. Symposium Program Schedule

Saturday 18th August 2012

14:00-17:00 Registration (Third floor of SHAO)

Sunday 19th August 2012 08:30-12:00 Registration (Third floor of SHAO) Opening Ceremony (Room A) (Shuhua Ye and Director of SHAO) 08:30-08:50 Chair: Shuanggen Jin 08:50-09:50 Keynote (Room A) Chair: Harald Schuh, Yaolin Shi 08:50-09:20 Space Geodesy Ground Networks and its Role in Space Geodesy Michael Pearlman , CFA, Harvard Uni., USA 09:20-09:50 Applying Geodetic Data in Computational Geodynamics to Understand Earthquake Physics Yaolin Shi (Academician), GUCAS, China Take photo at first floor & Coffee Break 10:10-12:30 Session 1A: Space Geodesy & Geodynamics (Room A) Chair: Richard Gross, Heping Sun 10:10-10:30 Recent Results from ITRF Combination Activities Zuheir Altamimi , IGN, Paris, France 10:30-10:50 Observations of the Superconducting Gravimeters and its Application in Geodynamics of the Earth's Interior (INVITED) Heping Sun , IGG, CAS, Wuhan, China 10:50-11:10 GPS/Galileo Earth Observation at GFZ: Recent activities and results (INVITED) Jens Wickert, GFZ, Potsdam, Germany 11:10-11:30 Rising of the lowest place on Earth due to Dead Sea water-level drop: Evidence from SAR interferometry and GPS Shimon Wdowinski, Uni. Miami, USA 11:30-11:50 Geodetic Very Long Baseline Interferometry (VLBI) and its future perspectives Harald Schuh, Vienna Uni. Tech., Austria 11:50-12:10 CICERO: Community Initiative for Cellular Earth Remote Observation Tom Yunck, GeoOptics Inc., USA 12:10-12:30 Panel discussion (Michael Pearlman, Yaolin Shi, Zuheir Altamimi ,Heping Sun, Jens Wickert, Shimon Wdowinski, Harald Schuh, Tom Yunck) nd Lunch (Cafeteria, 2 floor of Active Center Building) 13:40-15:05 Session 2: Space geodetic techniques and reference frame Chair: Zuheir Altamimi , Pengfei Chen 13:40-14:00 CPM-CGCS2000 Plate Motion Model (INVITED)

Pengfei Chen, Chin. Acad. Surveying & Mapping, China 14:00-14:20 A reference frame for geophysics and relativistic geodesy (INVITED) Pacome Delva, Observatoire de Paris, Paris, France

14:20-14:35 Results of the GLONASS measurements analysis Suriya K. Tatevian, Institute of Astronomy RAS, Russia 14:35-14:50 Separation of modulated seasonal signals from GPS time series with singular spectrum analysis Qiang Chen, Uni. Stuttgart, Germany 15:50-15:05 Present-day kinematics of Singapore: effects on the reference frame realization

Rui M. Fernandes, Universidade da Beira Interior, Portugal

15:10-16:25 Session 3: Earth Rotation (Room A) Chair: Roland Klees, Keke Zhang 15:10-15:25 The Rotational and Gravitational Signature of Recent Great Earthquakes Richard Gross, JPL, Caltech, USA 15:25-15:40 Second and high order effects on Earth precession and nutation (INVITED) Jose M. Ferrandiz, Uni. Alicante, Spain 15:40-15:55 Zonal tidal variations in UT1 derived within a VLBI global solution Sigrid Boehm, Vienna Uni. Tech., Austria 15:55-16:10 Estimation of Earth parameters of polar motion- Comparison of two approaches Stephanie Kirschner, Tech. Uni. Munich, Germany 16:10-16:25 Correspondence between free core nutation and nearly diurnal free wobble estimated from VLBI and ring laser gyroscopes Tobias Nilsson, Vienna Univ. of Tech., Austria Coffee Break Session 4A: GNSS & Applications (Room A) Session 4B: Earth Rotation (Room B) 16:35-18:05 Chair: Xiaohua Tong, Michael Pearlman Chair: Florian Seitz, Jose M. Ferrandiz 16:35-16:50 Relevance Analysis between Mass GNSS Phase Based Attitude Determination of Satellite: Redistribution and Length of Day Variations The Problem Revisited within Earth System Najam Naqvi, NPU, Xi'an, China Jian Sun, Wuhan Univ., Wuhan, China 16:50-17:05 Cycle-slip Detection in PPP based on Empirical Mode Symmetry-Relationship Database Management Decomposition System and its Application in ITRF Hong Hu, CUMT, Xuzhou, China Zhengcai Liu, Xiangtan Uni., China 17:05-17:20 On the use of BLITS satellites for precise positioning On the Interconnections of Different Coordinate Konstantin Ebauer, Institute of Astronomy, Moscow, and Time Systems Based on SOFA Russia Liu Chang, Wuhan Uni., Wuhan, China 17:20-17:35 Performance Analysis on Different Combined Integrity Estimation of High-frequency ERPs with GPS Schemes of Multi-constellation Navigation Observations Xiaojun Duan, Nat. Univ. Defense Tech., China Hongzhou Yang, Wuhan Uni., Wuhan, China 17:35-17:50 The performance of GPS and Compass/BeiDou-2 On the kinematic positioning of a lunar rover with constellation and positioning SBI technology Xu Tang, Hohai University, China Xuechuan Li, Wuhan Uni., Wuhan, China 17:50-18:05 Incorporating Seasonal Variations based on Support Vector Machine Aided Extended Kalman GRACE Measurements on Chinese Reference Filtering Algorithms for GPS/INS Integrated Navigation Frame Realization Xinglong Tang, CUMT, China Rong Zou, China Univ. Geosciences, China 18:30-21:00 Banquet (2nd floor, Sports Hotel) (Addressed by Shuhua Ye)

Monday 20th August 2011 08:00-09:55 Session 1B: Space Geodesy & Geodynamics (Room A) Chair: Wenke Sun, Pacome Delva, Tonie van Dam 08:00-08:20 Repeating earthquakes' as measures of deformation in deep: empirical and theoretical investigation (INVITED) Zhongliang Wu, CEA-IGP, Beijing, China 08:20-08:40 Third Pole Environment (TPE) Programme: A new base for the study of atmosphere-land interaction over the Tibetan Plateau and surrounding areas (INVITED) Yaoming Ma, ITP, CAS, Beijing, China 08:40-09:00 Shape, Winds and Gravity of rapidly rotating Jupiter (INVITED) Keke Zhang, University of Exeter, UK 09:00-09:20 Evaluation of potential fields generated by Earth’s mass components (INVITED) Pavel Novak, Univ. West Bohemia, Pilsen, Czech Republic 09:20-09:40 Spatial variations in sea level in the near field of melting ice: Effects of Alaskan glacier melting using a spatially realistic load model (INVITED) Emma Hill, Nanyang Tech. Uni., Singapore 09:40-09:55 Ocean circulation in Southern Ocean from GOCE gravity model Alberta Albertella, Tech. Uni. Munich, Germany Coffee Break 10:05-11:30 Session 5: SAR and Remote Sensing Applications (Room A) Chair: Qiming Zeng, Andy Hooper 10:05-10:25 ScanSAR Interferomtry Processing for Large Scale Ground deformation Surveying (INVITED) Qiming Zeng, PKU, Beijing, China 10:25-10:45 High-resolution constraints on the response to ice load changes in the Antarctic Peninsula and Iceland, using radar interferometry (INVITED) Andy Hooper, Delft Uni. Tech., Netherlands 10:45-11:00 Ground Deformation in the Kyoto Basin and Osaka Plain Detected with SAR Interferometry Manabu Hashimoto, Kyoto Univ., Japan 11:00-11:15 Indexing Method for LIDAR Points Cloud Data Based on Spatial Characteristics Zhipeng Li, Grad. Uni. Chin. Acd. Sci., Beijing, China 11:15-11:30 Unsupervised classification of dual band polarimetric SAR image using non-gaussian statistical models Arnab Muhuri, Indian Ins. Tech., India

11:35-12:35 Session 6A: Satellite Positioning (Room A) Session 6A: Gravity & Mass Transport Chair: Manabu Hashimoto, Qi Wang (Room B) Chair: Yaoming Ma, Pavel Novak 11:35-11:50 Bare Surface Scattering Properties Study in order A gravity field model from GOCE and combination for GNSS-R Applications with GRACE Xuerui Wu, Dalian Maritime University, China Weiyong Yi, Tech. Uni. Munich, Germany 11:50-12:05 Correcting Unmodeled Periodical Ocean Tidal Melting of ice-sheet in Tibet confirmed by satellite Loading at the Observation Level and Its Impact on gravity measurement (INVITED) Continuous GPS Coordinate Time Series Shuanggen Jin, Guiping Feng, SHAO, CAS,

Zhao Li, Wuhan Uni., China Shanghai, China 12:05-12:20 Study on Seasonal Variations Derived from Vertical Ocean Tide and Ocean Loading Models of the Component of GPS Site Position Time Series Yellow Sea Feng Zhou, CUMT, Xuzhou, China Sung-Ho Na, Korea Astron. Space Sci. Ins., South Korea 12:20-12:35 Change Detection about Coal Fire Districts by The average acceleration approach applied to Interpreting with Thermal Remote Sensing gravity coefficients recovery based on GOCE orbits Xiaomin Du, CUMT, Beijing, China Qiang Huang, SW Jiaotong Uni., China nd Lunch (Cafeteria, 2 floor of Active Center Building) 13:45-15:15 Session 7: GNSS Atmospheric Sounding (Room A) Chair: Jens Wickert, Thomas P. Yunck 13:45-14:00 A New Approach to Evaluating the Absolute Accuracy of Multiple Water Vapor Observation Techniques George Zhizhao Liu, Hong Kong Polytechnic Univ., Hong Kong 14:00-14:15 Response of ionospheric total electron content to super-intense geomagnetic storms: An investigation with dual frequency GPS observation data at IIT Bombay, Mumbai, India Sampad Kumar Panda, IIT-Mumbai, India 14:15-14:30 Statistical analysis of ionospheric TEC day-to-day variability Shun Zhang, Wuhan Uni., China 14:30-14:45 Diurnal Variation of Ground-based GPS-PWV under Different Solar Radiation Intensity in Chengdu Area Guoping Li, Chengdu Univ. Info. Tech., China 14:45-15:00 Near-real time ZTD model for the area of Poland Jan Kaplon, Wroclaw Univ. of Environ. & Life Sci., Poland 15:00-15:15 Research and Design on the Observation System of Navigation Constellation Inter-Satellite Links Wei Wang, Academy of Equipment, China Coffee Break 15:25-18:05 Session 8A: Crustal deformation & Earthquake Geodesy (Room A) Chair: Jeff. Freymueller , Zhongliang Wu 15:25-15:45 A precise velocity field of tectonic deformation in China as inferred from intensive GPS observations (INVITED) Qi Wang, Ins. Seismology of CEA & China Univ. Geosci., Wuhan, China 15:45-16:05 Numerical Simulations of Earthquake Fault Systems for Earthquake Physics, Forecasting, and Geodetic Data Analysis (INVITED) John Rundle, Uni. California, Davis, USA 16:05-16:20 Co-seismic Deflection Change of the Vertical Caused by the 2011 Tohoku-Oki Earthquake (Mw9.0) Wenke Sun, GUCAS, Beijing, China 16:20-16:35 Creation of strain maps from velocity field of deformation by on-line tools Milan Talich, Ins. Info. Theory & Automation, Prague, Czech Republic 16:35-16:50 Coriolis-induced state-rate law and strain energy function in coseismic rupture Bojing Zhu, GUCAS, Beijing, China Session 8B: Crustal deformation & Earthquake Geodesy (Room A) Chair: Shimon Wdowinski, John Rundle 16:50-17:05 Present-day 3D crustal movement in the Qinghai-Tibetan Plateau from GPS data (INVITED) Caijun Xu, Wuhan University, China 14

17:05-17:20 Inversion for the spatial distribution of afterslip following the 2007 Mw 8.4Bengkulu earthquake in Sumatra, using a principal component analysis-based inversion method (PCAIM) of SuGAR GPS time-series data Louisa L. Tsang, Nanyang Tech. Uni., Singapore 17:20-17:35 Evaluation of glacial isostatic adjustment uplift rates in the Tibetan Plateau from satellite gravimetry Tengyu Zhang, SHAO, Shanghai, China 17:35-17:50 Moderate-to-Large Earthquakes at the Sumatran subduction zone observed by the Sumatra GPS Array (SuGAr) Lujia Feng, Nanyang Tech. Uni., Singapore 17:50-18:05 Polar wander and Response to Earthquake of An Ideal Viscoelastic Earth Sung-Ho Na, Korea Astron. Space Sci. Ins., South Korea

18:05-18:30 Closing remarks & Farewell

Tuesday 21st August 2011

8:30-12:20 Summer School Opening Address & VLBI Geodesy Lecture (Room A)

nd Lunch (Cafeteria, 2 floor of Active Center Building) 14:00-18:00 International Forum: Long-Range Science Goals and Challenges for Geodesy (Room A) Session 1 Chair: Shuanggen Jin 14:00-14:20 How is going for future Geodesy (INVITED) Shuanggen Jin, SHAO, China 14:20-14:40 Next Generation ITRF: Problems, Plans and Challenges (INVITED) Zuheir Altamimi , IGN, Paris, France 14:40-15:00 Hydro-geodesy: Future Goals and Challenges (INVITED) Shimon Wdowinski, Uni. Miami, USA Coffee Break Session 2 Chair: Harald Schuh 15:10-15:30 Future VLBI Geodesy: Problems, Plans and Challenges (INVITED) Harald Schuh, Vienna Uni. Tech., Austria 15:30-15:50 Future Tectonic Geodesy Goals and Challenges (INVITED) Jeff Freymueller, Univ. Alaska, USA 15:50-16:10 GGOS: Future Roles and Prospective (INVITED) Richard Gross, JPL, Caltech, USA 16:10-16:30 CICERO Status and International Collaboration (INVITED) Tom Yunck, GeoOptics Inc., USA 16:30-18:00 Discussion 18:00-20:00 Reception and Party (3nd floor of SHAO )

Oral Talks (Backup) On the Chinese Spaceflight TT&C Network for Tiangong-1 Erhu Wei, Wuhan Uni., Wuhan, China

Spatial-Temporal Variations of Water Storage, Precipitation and Evapotranspiration in the Volta River Basin S. A. Andam-Akorful , HHU, Nanjing, China

Posters

Vladislav GPS performance deterioration under strong magnetic storm on Irkutsk State Railway Uni., Russia Demyanov February 17, 2011 in Japan Korea Astron. Space Sci. Ins., South Sung-Ho Na Seasonal variability of Global Earthquake Occurrence Korea Analysis of tides in Shahid Rajaee Port buoys using integrated least Abbas Uni. of Tehran, Iran squares harmonic constituent and Fourier series in simplified Abedini Geo-database Jianjun Zhu, Overview on modern surveying adjustment and theory of data Dongfang Central South Uni., China processing Lin On the Search Algorithm of Independent baselines for GNSS Data Erhu Wei Wuhan Uni., Wuhan, China Processing Ayman A. GRACE Detection of water storage variation in Africa and its SHAO, Shanghai, China Hassan response to climate events Tsunami modeling of a prehistorical giant submarine landslide Qiang Qiu Nanyang Tech. Uni., Singapore offshore of Brunei Nasser Snow depth and ice thickness in Northern Canada retrieved from SHAO, Shanghai, China Najibi GPS code-phase difference multipath signals Vagner G. Assessing mass transport in the Yangtze river basin using GRACE Hohai University, China Ferreira and TRMM satellite mission and river dischange observations

2. Summer School Schedule

Time Dates st Tuesday 21 August 2011

08:30-08:50 Welcome Address (Shuhua Ye and Director, SHAO, China)

08:50-10:20 VLBI Geodesy-1 (Harald Schuh, Vienna Uni. Tech., Austria)

Take Photo & Coffee Break

10:40-11:50 VLBI Geodesy-2 (Harald Schuh, Vienna Uni. Tech., Austria)

11:50-12:20 Questions & Discussion

Lunch

14:00-18:00 International Forum: Long-Range Science Goals and Challenges for Geodesy

14:00-15:00 Session 1 (Chair: Shuanggen Jin)

14:00-14:20 How is going for future Geodesy (INVITED) (Shuanggen Jin, SHAO, China )

14:20-14:40 Next Generation ITRF: Problems and Challenges (INVITED) (Zuheir Altamimi, IGN, France)

14:40-15:00 Hydro-geodesy: Future & Challenges (INVITED) (Shimon Wdowinski, Uni. Miami, USA)

Coffee Break 15:10-18:00 Session 2 (Chair: Harald Schuh)

15:10-15:30 Future VLBI Geodesy: Problems & Challenges (INVITED) (Harald Schuh, TUVien., Austria)

15:30-15:50 Future Tectonic Geodesy Goals and Challenges (INVITED) (Jeff Freymueller, Univ. Alaska, USA)

15:50-16:10 GGOS: Future Roles and Prospective (INVITED) (Richard Gross, JPL, USA)

16:10-16:30 CICERO Status and International Collaboration (INVITED) (Tom Yunck, GeoOptics Inc., USA)

16:30-18:00 Discussion with all lecturers and participants

18:00-20:00 Dinner Party nd Wednesday 22 August 2011

08:30-10:00 GNSS Atmosphere Remote Sensing-1 (Jens Wickert, GFZ, Potsdam, Germany)

Coffee Break

10:10-11:40 GNSS Atmosphere Remote Sensing-2 (Jens Wickert, GFZ, Potsdam, Germany)

11:40-12:20 Questions & Discussion Lunch 14:00-15:30 Tectonic/Earthquake Geodesy-1 (Jeffrey T. Freymueller, Uni. of Alaska, USA) Coffee Break 15:40-17:00 Tectonic/Earthquake Geodesy-2 (Jeffrey T. Freymueller, Uni. of Alaska, USA)

17:00-17:30 Questions & Discussion

Dinner

19:00-21:00 Practice and Discussion (Jeffrey T. Freymueller, Uni. of Alaska, USA)

rd Thursday 23 August 2011 The added value of GOCE to static and time-variable gravity field modelling-1 08:30-10:00 (Roland Klees, Delft Uni. Tech., Netherlands) Coffee Break The added value of GOCE to static and time-variable gravity field modelling-2 10:10-11:40 (Roland Klees, Delft Uni. Tech., Netherlands) 11:40-12:20 Questions & Discussion

Lunch

14:00-15:30 Earth Rotation-1 (Richard Gross, JPL, USA)

Coffee Break 15:40-17:00 Earth Rotation-2 (Florian Seitz, Tech. Uni. Munich, Germany) 17:00-17:30 Questions & Discussion 17:30-19:00 Dinner 19:00-21:00 Practice and Discussion (Roland Klees) th Friday 24 August 2011 08:30-10:00 TRF/ITRF-1 (Zuheir Altamimi, IGN, France)

Coffee Break

10:10-11:40 TRF/ITRF-2 (Zuheir Altamimi, IGN, France)

11:40-12:20 Questions & Discussion

Lunch

14:00-15:30 InSAR-1 (Manabu Hashimoto, Kyoto Univ., Japan)

Coffee Break

15:40-17:00 InSAR-2 (Manabu Hashimoto, Kyoto Univ., Japan)

17:00-17:30 Questions & Discussion

Dinner

19:00-21:00 Practice and Discussion (Manabu Hashimoto and Shimon Wdowinski) th Saturday 25 August 2011 08:30-10:00 GNSS & Geodesy (Shuanggen Jin, SHAO, CAS, China)

Coffee Break

10:10-12:00 Surface Mass Loading (Tonie van Dam, Uni. Luxembourg, Luxembourg)

12:00-12:20 Questions & Discussion

Lunch

14:00-15:30 Hydrologic Geodesy-1 (Shimon Wdowinski, Univ. of Miami, USA)

Coffee Break

15:40-17:00 Hydrologic Geodesy-2 (Shimon Wdowinski, Univ. of Miami, USA) 17:00-17:30 Questions/Discussion & Farewell

3. Abstracts

GGOS Ground Based Space Geodesy Networks Required to Improve the Reference Frame

Michael R Pearlman1, Erricos C Pavlis2, Chopo Ma3, Zuheir Altamimi4, Carey E Noll5, David A. Stowers6

1. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA, USA. 2. GEST, UMBC , Baltimore, MD, USA. 3. NASA GSFC, Greenbelt, MD, USAs 4. Institut Geographique National, Champs-sur-Marne, France 5. NASA GSFC, Greenbelt, MD, USA 6. Jet Propulsion Laboratory, Pasadena, CA, USA

Ground-based networks of co-located space geodetic techniques (VLBI, SLR, GNSS, and DORIS) are the basis for the development and maintenance of the International Terrestrial Reference Frame (ITRF), which is our frame of reference for measurements of global change. The Global Geodetic Observing System (GGOS) of the International Association of Geodesy (IAG) has undertaken the task to develop a strategy to design, integrate and maintain a modernized fundamental geodetic network and supporting infrastructure in a sustainable way to satisfy the long-term requirements for the reference frame. The GGOS goal is an origin definition at 1 mm or better and a temporal stability on the order of 0.1 mm/y, with similar numbers for the scale and orientation components. These goals are based on scientific requirements to address sea level rise with confidence, but other applications are not far behind. Simulations are underway to examine accuracies for origin, scale and orientation of the resulting ITRF based on various network designs and system performance to determine the optimal global network to achieve this goal. To date these simulations indicate that about 30 co-located stations with modern technology will be required to define the reference frame, and a more dense GNSS and DORIS network will be required to distribute the reference frame to users anywhere on Earth or in orbit. Additional sites with two or three co-located techniques would further densify and strengthen the network. Sites of the new global network should be geologically stable, with good weather, established infrastructure, and local support and personnel. Major strides in the technique improvements are also underway.

GGOS has issued a performance specification for new technology instruments based on guidelines from the geometric geodetic services and has developed a Site Requirements Document as a guideline for site selection and development.

In response to a GGOS Call for Participation for groups interested in participation in the GGOS network, fifteen groups, encompassing 35 sites, have expressed plans to participate. Other groups are encouraged to participate, and are expected to do so in the near future.

Recent Results from ITRF Combination Activities

Zuheir Altamimi IGN, France

The ITRF Product Center is conducting continuous analysis of the available and updated time series of the four space geodetic techniques in order to monitor the performance of the reference frame over time. Recent results of data analysis of extended time series beyond the ITRF2008 time-span, including refined IGS repro 1 solutions, will be presented and used to re-examine (1) the scale agreement between VLBI and SLR as well as the GNSS origin and scale consistency with SLR and VLBI, (2) the level of agreement between local ties and space geodesy estimates, with an emphasis on the impact of uncalibrated GNSS radomes and discontinuities at some co-location sites on the ITRF parameters.

Observations of the Superconducting Gravimeters and its Application in Geodynamics of the Earth's Interior Sun Heping Xu jianqiao Cui Xiaoming Lei Xiange Hu Xiaogang Institute of Geodesy and Geophysics, Chinese Academy of Science, Wuhan 430077

Abstract: By stacking a series of high-sampling and high- precision tidal gravity observations at 25 stations in the Global Geodynamics Project (GGP) network along the world, we investigate some problems in the Earth geodynamics, including the Earth's free core nutation (FCN), Earth's free oscillation and the translational oscillation of the solid inner core. We determined corresponding parameters including the eigen-period, quality factor (Q value) and resonance strengthand so on, the enviromental influence of the atmospheric pressure and the oceanic loading are take into account during the data processing. The high precision tidal gravity amplitude factors are determined, the dynamic viscosity at the core-mantle boundary (CMB) is obtain for the first time based on the FCN quality factor Q values which reaches at up to the order of 103 Pa·s, it is in good agreement with the nearest result obtained using the VLBI observations. Our results indicate that the tidal gravity is one of effective techniques for investigating the deep interior structure of the Earth. Contact Adress: Email: [email protected] Tell: 0086-27-68881323（O）； 13607144226（M）;

A New Approach to Evaluating the Absolute Accuracy of Multiple Water Vapor Observation Techniques

Zhizhao Liu, Min Li, Weikun Zhong Department of Land Surveying & Geo-Informatics The Hong Kong Polytechnic University Hung Hom, Kowloon, Hong Kong Tel: (852)2766 5961 Fax: (852)2330 2994 E-mail: [email protected]

Water vapor is an important component of Green House Gases (GHG) and one of key parameters in water forecasting and climatology research. Its measuring accuracy can affect results of many meteorological prediction processes. A lot of ground-based and space-based water vapor observation techniques are available. However no method has been developed to evaluate the absolute accuracy of each type of water vapor instrument. Radiosonde has long been regarded as the most accurate approach but its accuracy has not been validated in an absolute sense. In this research, water vapor data observed from four types of ground-based water vapor measurement instruments are evaluated in a Global Positioning System (GPS) Precise Point Positioning system. The four types of instruments are: GPS, radiosonde, sunphotometer, and water vapor radiometer (WVR). All the instruments except radiosonde are located on the campus of the Hong Kong Polytechnic University (PolyU), Hong Kong. The Radiosonde has just 1-km distance from the PolyU and it is operated by the Hong Kong Observatory (HKO). The WVR instrument is first calibrated by the water vapor data from GPS, sunphotometer and radiosonde and 3 different sets of coefficients are obtained. Consequently 3 sets of WVR water vapor data are reduced from the coefficients. The 3 sets of water vapor measurements are then assimilated with GPS PPP system to correct the wet delay in GPS signals. This technique is called PWV-Assisted PPP. The multi-months PPP solutions are analyzed and standard deviations are computed. It is considered that the more accurate water vapor data can correct the wet delay better. Thus the PWV-Assisted PPP accuracy will be higher accordingly. Through such a comparison, the water vapor measurements from various instruments/techniques can be evaluated in an absolute sense. The GPS positioning model can be regarded as an absolute metric to judge the accuracy of different water vapor measurement instruments. The 3-month daily solutions of PWV-Assisted PPP results show that after the removal of biases between the different techniques, the positioning accuracy of using GPS-calibrated WVR water vapor data have a better consistency than other solutions. The height RMS of PPP-Assisted solutions using WVR water vapor calibrated by GPS derived PWV, radiosondes and Sunphotometer are 1.8 cm, 2.2 cm, and 3.7 cm, respectively.

Third Pole Environment (TPE)Programme: A new base for the study of atmosphere-land interaction over the Tibetan Plateau and surrounding areas

Yaoming Ma, Tandong Yao Key Laboratory of Tibetan Environment Change and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, 4A Datun Road, Beijing 100101, China, e-mail: [email protected]

Centered on the Tibetan Plateau, the Third Pole area stretches from the Pamir and Hindu Kush in the west to the Hengduan Mountain in the east, from the Kunlun and Qilian mountain in the north to the Himalayas in the south, covering over 5000km2 with an elevation higher than 4000m. As a unique geological and geographical unit, the Third Pole area dramatically impacts the world’s environment and especially controls climatic and environmental changes in China, Asia and even in the Northern Hemisphere. Supported by the Chinese Academy of Sciences and some international organizations, the Third Pole Environment (TPE) Porgramme is now implementing. TPE is focusing on the land-surface processes and environment over the plateau and surrounding areas, with an emphasis on atmosphere–land interaction. Firstly the background of the establishment of the TPE, the establishing and monitoring plan of long-term scale of the TPE and six comprehensive observation and study stations will be introduced. Then the preliminary observational analysis results, such as the characteristics of land surface fluxes partitioning (“imbalance”, diurnal variation,

inter-monthly variation, inter-yearly variation and vertical variation etc), air temperature, pressure, air humidity, wind speed and wind direction, the structure of the Atmospheric Boundary Layer (ABL) will also been shown. The study on the regional distribution of land surface heat fluxes of paramount importance over heterogeneous landscape of the Third Pole area. A parameterization methodology based on Moderate Resolution Imaging Spectroradiometer (MODIS) and in-situ data is described and tested for deriving the regional surface heat fluxes (net radiation flux, soil heat flux, sensible heat flux and latent heat flux) over heterogeneous landscape. As a case study, the methodology was applied to the whole Tibetan Plateau area. Four scenes of MODIS data (30 January 2007, 15 April 2007, 1 August 2007 and 25 October 2007) were used in this study for the comparison among four seasons. The derived results were also validated by using the ‘‘ground truth’’ measured in the stations of the Tibetan Observation and Research Platform (TORP). It was shown that reasonable regional distribution of surface heating field over heterogeneous landscape of the Tibetan Plateau can be obtained reasonably by using this methodology. The shortage and further improvement of the methodology was also discussed.

Rising of the lowest place on Earth due to Dead Sea water-level drop: Evidence from SAR interferometry and GPS

S. Wdowinski1, R. N. Nof2,3, A. Ziv4, M.-P. Doin5, G. Baer3, Y. Eyal2, Y. Fialko6, and Y. Bock5 1. Division of Marine Geology and Geophysics, University of Miami, Miami, Florida, USA. 2. Department of Geological and Environmental Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel. 3. Geological Survey of Israel, Jerusalem, Israel. 4. Geophysics and Planetary Sciences, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel-Aviv University, Tel-Aviv, Israel. 5. Laboratoire de Géologie, École Normale Supérieure, CNRS, Paris, France. 6. Scripps Institution of Oceanography, University of California, San Diego, California, USA.

The Dead Sea water-level has been dropping at an exceedingly increasing rate since 1960, and between 1993 and 2001, the interval of the InSAR data examined in this study, it has dropped at an average rate of 0.88 m per year. Such a water-level change could potentially give rise to a resolvable lithospheric rebound and regional uplift, with spatial extent and amplitude that are controlled by the effective mechanical properties of the crust and upper mantle combined. We measure that deformation for the years 1993 to 2001, using 149 short baseline interferograms made of 31 ERS-1 and ERS-2 Synthetic Aperture Radar (SAR) images and continuous GPS data from the Survey of Israel recorded between 1997 and 2011. The uplift rate at the Dead Sea is small (up to 4 mm/year), and the basin topography is almost a mirror of the displacement, introducing a strong trade-off between uplift and stratified atmosphere noise. To overcome this complication, we impose a linearity constraint on the satellite to ground Line Of Sight (LOS) phase changes based on the steady uplift observed by a continuous GPS station in the area of interest, and simultaneously solve for the LOS change rate, Digital Elevation Model (DEM) errors and the elevation-phase correlation. While the LOS rate and DEM errors are solved for each pixel independently, the elevation-phase correlation is solved for each SAR acquisition independently. Using this approach we separated the stratified atmospheric delay from the ground

displacement. We observed a regional uplift around the Dead Sea northern basin, with maximum uplift close to the shorelines, and diminishing to zero by the Mediterranean coast. We modeled the effect of water load changes using a homogeneous elastic half-space, and found a good agreement between modeled and observed ground displacements using elastic properties that are compatible with seismic and gravity data down to a depth of 15 km below the Dead Sea basin, suggesting that the response of the crust to the sea level drop is controlled mainly by the elastic properties of the upper-crust immediately below the Dead Sea basin.

Geodetic Very Long Baseline Interferometry (VLBI) and its future perspectives

Harald Schuh Institute of Geodesy and Geophysics, University of Technology, Vienna, Austria

Since the 1970s Very Long Baseline Interferometry (VLBI) has proven to be a main space geodetic technique by determining precise coordinates on the Earth, by monitoring the variable Earth rotation and orientation with highest precision, and by deriving many other parameters of the Earth system. VLBI provides an important linkage to astronomy through, for instance, the determination of very precise coordinates of extragalactic radio sources. It even contributes to determining parameters of relativistic or cosmological models. After a short review of the history of geodetic VLBI and a summary of recent results, the presentation will deal with future perspectives of this fascinating technique. The International VLBI Service for Geodesy and Astrometry (IVS) is well on its way to fully defining a next generation VLBI system, called VLBI2010. The goals of the new system are to achieve 1-mm position and 0.1-mm/year velocity accuracy over a 24-hour observing session. Continuous observations shall be carried out in the future, that is observing 24 hours per day seven days per week, with initial results to be delivered within 24 hours after taking the data. Special sessions, e.g. for monitoring the Earth rotation parameters, should even provide the results in near real time. These goals require a completely new technical and conceptual design of VLBI measurements. Based on extensive simulation studies, strategies have been developed by the IVS to significantly improve its product accuracy through the use of a network of small (~12-m) fast-slewing antennas. A new method for generating high precision delay measurements and improved methods for handling biases related to system electronics, deformations of the antenna structures, and radio source structure have been developed. Furthermore, as of May 2012, the construction of fifteen new VLBI2010 sites with global distribution has already been funded, with good perspectives for one dozen more antennas. This will improve the geographical distribution of geodetic VLBI sites on Earth and provide an important step towards a global network called VGOS (VLBI2010 Global Observing System).

CPM-CGCS2000 Plate Motion Model Pengfei Cheng1 Yingyan Cheng 1 Jingzhong Mi1 Hua Wang1 Suqin Wu 2 1 Chinese Academy of Surveying and Mapping, 2 RMIT University

The China Geodetic Coordinate System 2000 (CGCS2000) was first officially declared as the national standard coordinate system on July 1, 2008. This system was defined in the ITRF97 frame at epoch 2000.0 and included 2600 GPS geodetic control points. As a result, all GNSS results obtained since the reference epoch need to be transformed to CGCS2000. For high accuracy transformation results, using a plate model for

correcting possible plate movement is necessary. Thus, the accuracy of the plate model used will determine the accuracy of the transformation results. Various plate models such as NNR NUVEL1A, APKIM2005 and PB2002 have been developed by researchers all over the world. However, these models unlikely perform well in China because control points from China used in the development of these models are insufficient and also not well-distributed. In order to improve the accuracy of the transformation results for mainland China, in this research, a more accurate velocity field was developed using the observations from the 10-year period 2001−2010 and from 1079 GPS stations of the Crustal Movement Observation Network of China. From the obtained velocity field and based on China plate tectonics, the new regional plate model, named CPM-CGCS2000 (China Plate Model-CGCS2000) was derived. The results showed that the precision of the optimal parameter estimates of the new model were better than 1 mm/yr in most parts of China ; the best, the worst and the average precision values were 0.69 mm/yr, 5.02 mm/yr and 1.72 mm/yr respectively. These figures indicate that the new model well fits the observation data set. For a validation of the new model, the Euler vector estimates obtained from the 20 sub-plate were also used to perform the coordinate transformation for tens of national fiducial stations. The results showed that the differences between the transformed and the known coordinates of these points in CGCS2000 were 2−3 cm. As expected, this accuracy is higher than all the existing commonly used plate models including the two domestic ones developed by Fuyang (2002) and Wei Ziqing (2011).

A reference frame for geophysics and relativistic geodesy

Pacome Delva, Observatoire de Paris, Paris, France

A constellation of satellites equipped with inter-satellite links naturally realizes an autonomous relativistic positioning system. Given the dynamics of the constellation of satellites, it is possible to define a spatio-temporal dynamical reference frame anchored to the constellation: the ABC (Autonomous Basis of Coordinates) reference frame. This reference frame is independent from all other systems, and thus could help to refine these others systems. As it is based on well known satellite dynamics, it is highly accurate and stable.

It will open new possibilities in geophysics: aiming for absolute positions of markers on Earth at sub-millimeter accuracy, it would be possible to study the interior structure of Earth, continental drifts, ocean currents, geopotential differences and maybe earthquakes. The constellation of satellites probes the geometry of space-time, acting as a gravimeter. The link of the ABC reference frame with other reference frames will help to understand how the local geometry around Earth is embedded in the global arena of space-time. Finally, applying this concept to far-away clocks (eg. pulsars) will open new possibilities for solar system navigation.

Results of the GLONASS measurements analysis.

Tatevyan S.K., Kuzin S.P. Institute of astronomy RAS, Moscow, R.F.

With the purpose of improving the national geodetic reference frame an establishment of the new

Fundamental Astro-Geodetic network (FAGN), based mainly on the combined use of GPS and GLONASS measurements, is now carried out in Russia. From the geodetic point of view, the advantages of combining both systems are numerous, especially in the urban, mountain and near polar areas. More than 30 permanent core sites of this network are provided with the dual GPS/GLONASS receivers. Several core sites of the FAGN network are collocated with the existing IERS stations, equipped with the SLR, VLBI and DORIS instruments. Now the constellation of the GLONASS consists of 24 satellites at three orbital planes, 8 satellites in each. Inclination of the orbit is 64.80, height 19100 km and revolution time 11h 15min. Analysis of the GLONASS data, obtained at the IGS sites, including most of the Russian sites, have been made with the use of GIPSY-OASIS 2 software. Results of estimation of GLONASS orbital parameters and station coordinates were compared with the GPS estimations at the collocated sites. Both solutions are related to the ITRF2005 coordinate system. Differences between solutions are in the limit of a few cm. The means of improvement of the GLONASS solution and adjustment of the GLONASS coordinate system with the ITRF are considered.

Separation of modulated seasonal signals from GPS time series with singular spectrum analysis

Qiang Chen1, Tonie van Dam2, Nico Sneeuw1, Xavier Collilieux3, Paul Rebischung3 1. Institute of Geodesy, University of Stuttgart, Stuttgart, Germany 2. Faculte des STC, University of Luxembourg, Luxembourg, Luxembourg 3. IGN/LAREG and GRGS, Marne la Vallee, France

Seasonal signals in GPS time series are of great importance for understanding the evolution of regional mass, i.e. ice and hydrology. Conventionally these signals (annual and semi-annual) are derived by least-squares fitting of harmonic terms with a constant amplitude and phase. In reality, however, such seasonal signals are modulated, i.e., they will have a time-variable amplitude and phase. Recently, Davis et al.,(2012) proposed a Kalman filter based approach to capture the stochastic seasonal behavior of geodetic time series. Singular Spectrum Analysis (SSA) is a non-parametric method which uses time domain data to extract information from short and noisy time series without prior knowledge of the dynamics affecting the time series. A prominent benefit is that obtained trends are not necessarily linear and extracted oscillations can be amplitude and phase modulated. In this work, the capability of SSA for analyzing time-variable seasonal signals from GPS time series is investigated. We also compare SSA-based results to two model-based results, i.e. least-squares analysis and Kalman filtering. Our results show that singular spectrum analysis could be a viable and complementary tool for exploring modulated oscillations from GPS time series.

Present-day kinematics of Singapore: effects on the reference frame realization

Rui M. S. Fernandes,UBI, IDL, Portugal Victor Khoo,SLA, Singapore Durairaju Kumaran Raju,TMSI, NUS, Singapore Machiel S. Bos,CIIMAR/CIMAR, Porto, Portugal Wim Simons,TUDelft, Delft, The Netherlands

SiReNT (Singapore GNSS Reference Network) was established in 2006 bySLA (Singapore Land Authority). It is currently formed by seven stations distributed by the entire territory of Singapore.Two of these stations have beeninstalled recently (2010 and 2012) but the other five have been working continuously withalmost no data gaps and no receiver and antenna replacements. This makes possible to accurately monitor the stability of the network, both internally and with respect to the tectonics of the region. In this respect, Singapore is located inside of the Sundaland tectonic plate, which borders are some of the most active plate boundaries in the world. In this work, we study the internal stability of the network which is fundamental to use the stations as the permanent materialization of the Singaporean Reference Frame. The local time-series are investigated in order to evaluate the type of errors that are presented:real local tectonic movements, or site characteristics, likemonument instability. In addition, we use the computed velocity field to investigate the consistency of the observed solutions with the present-day kinematics of the Sundaland block. We test if the published angular velocity modelsof the Sundalandplate truly represent the observed motions of the Singaporean stations.In particular, we analyze the influence on the network of the September 2007 Sumatra earthquakes, the major series of seismic events after December 2004,which signature is clearly visible on the trend series. These results are compared with other published solutions for stations in the same region.

The Rotational and Gravitational Signature of Recent Great Earthquakes

R. S. Gross (Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA; e-mail: [email protected]; ph: 818-354-4010)

Besides generating seismic waves, which eventually dissipate, an earthquake also generates a static displacement field everywhere within the Earth. This global displacement field rearranges the Earth’s mass thereby causing the Earth’s rotation and gravitational field to change. The size of this change depends upon the magnitude, focal mechanism, and location of the earthquake. Using a spherical, layered Earth model, the coseismic effect of the recent great 2004 Sumatran, 2010 Chilean, and 2011 Japanese earthquakes upon the Earth’s length-of-day, polar motion, and low-degree harmonic coefficients of the gravitational field are computed. While the effects of these earthquakes have been observed in GRACE gravity measurements, the challenge of observing them in Earth rotation and low-degree SLR gravity measurements lies in being able to accurately model and remove the much larger atmospheric, oceanic, and hydrologic signals.

Zonal tidal variations in UT1 derived within a VLBI global solution

Sigrid Böhm, Johannes Böhm, Hana Krásná, Harald Schuh

Long-period solid Earth and ocean tides, generated by the zonal part of the tidal potential, are responsible for approximately one half of the universal time (UT1) variability at periods from few days to one year. These zonal tidal variations are superimposed by seasonal and intra-seasonal fluctuations due to pressure changes and zonal wind fields in the atmosphere and to a smaller extent also by non-tidal variations caused by ocean

currents. The strictly periodic tidal terms can be derived from time series of UT1 observations if atmospheric and non-tidal oceanic excitations are adequately accounted for. In this study we present an attempt to estimate zonal tidal variations directly within a VLBI global solution, i.e. simultaneously to station positions, clocks, troposphere delay and various other geodynamical and astronomical parameters. Such an approach bears the intricacy that the estimates actually represent increments to a priori values. The extracted harmonic components are thus residuals to the harmonic variations which are already inherent in the a priori UT1 line. In order to obtain the complete zonal tidal terms it is inevitable to consider the corresponding portion contained in the a priori time series. We employed the global solution of the Vienna VLBI Software (VieVS) to simultaneously adjust the observations of selected sessions spanning 1984-2011. The directly estimated zonal tidal variations up to the monthly period are discussed in comparison with the results of a straight time series approach.

Estimation of Earth parameters of polar motion - Comparison of two approaches

Stephanie Kirschner and Florian Seitz Earth Oriented Space Science and Technology (ESPACE), Technische Universität München, Arcisstr. 21, D-80333 Munich, Germany

The Earth’s rotation is physically described by the Euler-Liouville equation which is based on the balance of angular momentum in the Earth system. The Earth orientation parameters (EOP), polar motion and length of day (LOD), have been observed precisely over several decades. Also the influences of the different subsystems of the Earth (e.g. atmosphere, ocean, …) to the excitation of EOP variations via the tensor of inertia and relative angular momentum are known well from geophysical model data (e.g. NCEP, ECCO, … ). Therefore it is possible to invert the Euler-Liouville equation and solve it for uncertain Earth parameters that influence polar motion and LOD. We concentrate on the estimation of parameters related to period and damping of the free rotation of the Earth (Chandler oscillation). In order to make use of the long EOP time series, a recursive Gauss-Helmert adjustment approach and an adaptive Kalman filter procedure are being developed. We present the principles of both approaches and compare their numerical results. It will be shown that the application of the improved parameters leads to significantly better simulation results for polar motion compared to the original value taken from the Conventions of the International Earth Rotation and Reference System Service (IERS).

The study is carried out in the frame of the German DFG research unit on Earth Rotation and Global Dynamic Processes.

Correspondence between free core nutation and nearly diurnal free wobble estimated from VLBI and ring laser gyroscopes Tobias Nilsson, Johannes Böhm, Sigrid Böhm, Harald Schuh Institute of Geodesy and Geophysics, Vienna University of Technology

The free core nutation (FCN) is a free oscillation of the rotation axis of the Earth. It has a period of about 430 days in the celestial reference frame and is caused by the existence of a fluid outer core. In space geodetic data

analysis FCN is normally modelled as a nutation offset. However, if polar motion is estimated with sub-diurnal resolution the FCN can just as well be modelled as part of polar motion. In this case, the phenomena is called the nearly diurnal free wobble (NDFW) since its period is nearly retrograde diurnal. Theoretically, both methods should be equivalent and give the same results. To test this correspondence we analyse 20 years of VLBI data make two different solutions: one where polar motion, UT1, and nutation are estimated with daily resolution, and one where polar motion and UT1 are estimated with hourly resolution and nutation is fixed to the IAU2006 model. The FCN period and amplitude estimated from the nutation offsets of the first solution are compared to the corresponding NDFW parameters estimated from the polar motion of the second solution. The reasons for any observed differences are discussed and recommendations are made on what is the best representation of FCN/NDFW in VLBI data analysis. Furthermore, we investigate the possibility to detect the NDFW with ring laser gyroscopes.

GNSS Phase Based Attitude Determination of Satellite: The Problem Revisited

Naqvi Najam Abbas Space Academy, Department of Astronautics Northwestern Polytechnical University, Xi’an, China 127, You Yi Xilu, Xian 710072, Shaanxi, China [email protected]

Attitude Determination (AD) of a spacecraft and for the formation of spacecrafts using the phase measurements of the Global Navigation Satellite System (GNSS) is an active area of research. Many space based GPS receivers have been designed, tested and patented too. Various attitude determination algorithms have been developed in yester years for spacecrafts using different sensors but the last two decades have witnessed a phenomenal increase in research related with commercial-of-the-shelf (COTS) GPS receiver as a stand-alone sensor for determining the attitude of satellite using the phase measurements of the signals from GNSS. The GNSS-based Attitude determination algorithms have been experimented in many real missions. The problem of AD algorithms using GNSS phase measurements has two important parts; the ambiguity resolution and the determining of attitude while implementing the principle of Triliteration and measuring the base line length. Ambiguity resolution is the widely addressed topic in literature for implementing the AD algorithm using GNSS phase measurements for achieving the accuracy of millimeter level. This paper broadly overviews and revisits the different techniques and algorithms for estimating the attitude of satellites and for resolving the integer ambiguities encountered in AD using GNSS phase measurements.

Keywords- GNSS; Attitude Determination; Estimation Techniques; Ambiguity Resolution

Cycle-slip Detection in PPP based on Empirical Mode Decomposition

HU Hong1,2, GAO Jing-xiang1, WANG Jian1,2, YAO Yi-fei1,2 （1 China University of Mining and Technology, Jiangsu Key Laboratory of Resources and Environmental Information Engineering，Xuzhou 221116， 2 China1 School of environment and spatial informatics, China University of Mining and technology(CUMT), Xuzhou, 221116,China）

Abstract Cycle-slips remain undetected will significantly degrade the accuracy of precise point positioning (PPP). However, cycle-slip detection in PPP can only use single dual-frequency receiver which is more complicated than double differential combined model. In this paper, a new method for detecting cycle-slips of the carrier phase measurements based on empirical mode decomposition (EMD) is proposed. The zero-differential test volume was detected based on EMD and wavelet. Field experiments with real receiver are presented to demonstrate the effectiveness of the proposed algorithm; it shows that the new method can obtain good result using EMD method if the cycle slip is within 10, especially for small cycle slips. Moreover, comparing with the wavelet method, EMD do not need to select specific parameters, which can avoid the shortcoming caused by selecting not appropriate wavelet base.

On the use of BLITS satellites for precise positioning.

K. Ebauer, S.Tatevian, Institute of astronomy RAS, Moscow, RF.

The first satellite of the BLITS (Ball Lens In The Space) line with a diameter 170.3 mm has been launched in September 2009. The satellite is a duplex composition of the special spherical glass elements. Operating principle of the laser retro reflector is based on the refraction effects in the Luneberg lens. Thus a precision connection of the center of an optical refraction with the satellite center of mass is achieved with a target error less than 100 µkm under the different conditions of the satellite orbiting and for free input radiation angles. A zero signature of the laser pulse refraction is realized. The satellite mass is 7.5 kg, an effective surface of dissipation is 100000 м2. Orbital parameters are: altitude 832 km, inclination - 98.80, Development of a constellation of three BLITS satellites with different inclinations and orbital altitudes is planned. In this work a determination of the optimal set of orbital parameters for the next BLITS satellites are considered, as well as possible ways of their use for precise positioning.

Performance Analysis on Different Combined Integrity Schemes of Multi-constellation Navigation

Xiaojun Duan*, Lijun Peng, Wenqiang Yang, Yan Zheng, Jing Yao Department of Mathematics and Systems Science, College of Science, National University of Defense Technology, Changsha 410073, Hunan Province, P. R. China *Corresponding author: [email protected]

Integrity is the capability of sending the alarm to the users timely when the navigation system is out of use and it is a significant performance parameter of satellite navigation system. A user may receive signals coming from several different satellite systems in future. For local users, it is important to make full use of the whole integrity information of all the constellations. It is necessary to take advantage of the integrity information coming from multiple satellite constellations in order to prevent users from errors that might represent an excessive risk. The GPS, Galileo and COMPASS may be applied in combination in future, which would improve and enhance the positioning accuracy and availability. Therefore, users could take full advantage of three constellations of integrity information. As different navigation systems calculate the integrity in different ways,

it is important to give an appropriate combined integrity strategy of the three systems. From two aspects of integrity concept, HPL/VPL and integrity risk, this paper compares different combination of constellations. Since GPS employs the protection level concept, while Galileo prefers to compute the integrity risk at the alarm limit, also the Compass uses the similar Integrity concept with GPS/SBAS system, this paper examines GPS and Galileo integrity concept separately first. Using both “GPS-Based Integrity (ARAIM)” strategy and “Galileo-Based Integrity” strategy, corresponding different integrated integrity equations for combined integrity approaches using data from GPS and Galileo and Compass are constructed, and their results are analyzed for comparison. Accordingly the improvement of combined positioning and integrity performance is analyzed theoretically. The Combined integrity analysis with comparison of different strategies of GPS, Galileo and Compass would provide support for the future choice of combining integrity for multiple navigation constellations.

Keywords: Multi-constellation navigation system; Combined integrity; integrity monitoring; ARAIM.

Research and Design on the Observation System of Navigation Constellation Inter-Satellite Links

Wang Wei1,2，Dong Xurong1 1.Academy of Equipment, Beijing ,China 2.Beijing Institute of Tracking and Telecommunicaton Technology, Beijing ,China

Abstract: In accordance with the development characteristics of inter-satellite links (ISLs) between GNSS navigation satellites both at home and abroad, the design feature of ISL is discussed and summarized and the technical feature of its two representative systems – continuous observation system and time sharing observation system - are demonstrated in combination with the design requirements of different navigation systems. Furthermore, a comprehensive ISL scheme of continuous and time sharing observation systems and an inter-satellite measurement method featuring independent time synchronization and integrated data resolving capabilities on basis of this scheme are put forward. The experiment results suggest that inter-satellite observation system of this kind can fully the system’s demands for measurement performance, providing valuable reference of ISL design and optimization of global navigation constellation.

Polar wander and Response to Earthquake of an Ideal Viscoelastic Earth

Sung-Ho Na Korean Astronomy and Space Science Institute, South Korea

The principal axis of the earth, which coincides with the time average pole, drifts mainly due to glacial isostatic adjustment (GIA). In this study, an ideal viscoelastic earth is adopted for formulation of polar wander associated with GIA. Corresponding Green’s function for deformation of the earth is given as spatial part multiplied by time response part. The response of the same ideal viscoelastic earth to an earthquake is formulated as well.

Relevance Analysis between Mass Redistribution and Length of DayVariationswithin Earth System

Jian Sun

School of Geodesy and Geomatics, Wuhan University, 129 Luoyu Road, Wuhan 430079, China

Abstract:The variationin lengthofday(LOD)is principally the resultof movement and redistribution ofmass on the Earth’s surface. This studyanalyzed the Earth’s surfacemass redistributing impacts on LODwithintheEarth system.Since the variation of day length caused by mass redistribution is one order of magnitude less than observed day length, several signals wereremoved, which were not associated with mass redistribution within the Earth system.Then the combined excitation of Earth’s surface fluids mass was calculated due to atmosphere, ocean, continental water, Antarctic and Greenland ice (AOWI). The daily Earth’s surface atmospheric pressure data is from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis, the ocean bottom pressure data is from Estimating Circulation and Climate of the Ocean (ECCO) model, and monthly water storage change is from the Climate Prediction Center (CPC)’s land data assimilation system model. The excitation to LOD from Antarctica and Greenland was calculated by the data form Ice, Cloud, and land Elevation satellite (ICESat). Finally,relevance between the AOWIand the preprocessed day length wasanalyzed. It was found that the Earth’s surfacemass redistribution was the dominatingsignal in preprocessed day lengthat seasonal timescales. Keywords: ICESat; thelengthof day; excitation About the first author: SUN Jian, a graduate student specialized in the study of Earth’s Gravity Field E-mail: [email protected]

Symmetry-Relationship Database Management System and its Application in ITRF

Zheng-cai Liu Civil Engineering & Mechanics College, Xiangtan University, Xiangtan, Hunan, 411105, P. [email protected]

The scale of the ITRF solution files has been increasingly and rapidly expanded. For example, ITRF2005.snx.gz contains about 4.0 gigabytes of data, and ITRF2008-EOP-IVS.snx.gz contains about 7.6 Gb. In each SINEX file of ITRF, symmetrical matrix’s scale may constitute 95% of the file size. When managing the general information, the very large-scale symmetrical matrices in ITRF must be effectively stored, managed and shared in order to make full use of its important role. The symmetrical matrices have not been directly and conveniently managed by the RDBMS due to their half-structural properties—there are no fixed fields and the column number varies with the row number at the same time. The data management of symmetrical matrices based on the ASCII text file management system has been increasingly faced with some great difficulties and challenges. This paper put forward the ITRF data management based on the symmetry-relationship model (SR_Model). The SR_Model is employed in the the paper to extend the relationship database management system (RDBMS), and the symmetry-relationship database management system (SR_DBMS) is constructed to manage efficiently the very large scale

symmetrical matrices in ITRF when the relationship tables are managed. A new researching idea is therefore raised in this paper. First, the half-structural symmetrical matrices without fixed fields are converted into the full-structural relationship tables with fixed fields using the index transform formulae. Then, the symmetry-relationship databases are set up in accordance with extended relationship principles to manage the converted symmetrical matrices. Finally, the managing results by SR_DBMS are converted into the original form of the symmetrical matrices to be conveniently used by the users. The theory based on the SR_DBMS is tentatively developed, and the symmetry-relationship module (SR_Module) is initially developed in the software environment of the Windows Vista and Visual FoxPro 9.0, with the example of some datasets in ITRF2000 and ITRF2005, the experiments of the function tests and the efficiency tests are performed according to the principle of the software engineering. This research shows that the SR_DBMS with no loss of efficiency or convenience of management of relationship tables can save the memory size of disks by 65.8% and can improve the time efficiency by more than a hundred times when managing very large scale symmetrical matrices, compared with the traditional ASCII file management system. The datasets of ITRF, whose symmetrical matrices always occupy more than 95% of the file size, are typical datasets with very large scale of symmetrical matrices, and can be fully managed with the SR_DBMS.

KEY WORDS: Very Large-Scale Symmetrical Matrices, Index transform, Symmetry- Relationship, ITRF Datasets, SR_Module

On the Interconnections of Different Coordinate and Time Systems Based on SOFA Erhu WEI, Liu CHANG School of Geodesy and Geomatics,Wuhan University,129 Luoyu Road ,Wuhan 430079,China

Abstract: The SOFA software is a collection of subroutines that implement official IAU algorithms for earth attitude ,time scale and calendar computations. ITRS and ICRS are the fundamental reference systems. In this paper, the development of ITRS and ICRS are concluded, the different ways of transformation between ICRS and ITRS based on SOFA are analyzed. Secondly, the study of space geodesy are based on a certain Time Scale. In this Paper some time scales are discussed, classification of time scales are concluded, translation theories between them are introduced. Differences between different time scales are analyzed by real count data.

Keywords: SOFA, ITRS, ICRS, Time Scales, transformation, conversion, examples

Estimation of High-frequency ERPs with GPS Observations

Erhu WEI, Hongzhou YANG, Qi CAO School of Geodesy and Geomatics,Wuhan University,129 Luoyu Road ,Wuhan 430079,China

Abstract: This paper introduces the theory and method of solving the Earth's rotation parameters by GPS technology. As a result of analysis, about 80 IGS reference stations are selected in paper to process data acting on a time unit of eight hours. The object of this calculation is ERP sequential values with a two-hour time interval. The high-frequency time series of earth rotation parameter is analyzed by Fast Fourier Spectrum

Analysis. As a result of Fast Fourier Spectrum analysis, the diurnal and semi-diurnal ERP variations are obtained in this paper.

Keywords: GPS; lunar rover vehicle; earth rotation parameter; GAMIT; spectrum analysis

‘Repeating earthquakes’ as measures of deformation in deep: empirical and theoretical investigation

Wu Zhongliang, Jiang Changsheng, Han Libo, Ma Xiaojing Institute of Geophysics, China Earthquake Administration, Beijing Li Yutong Earthquake Administration of Liaoning Province, Shenyang

Measuring the deformation in deep, ‘repeating earthquakes’ identified by waveform cross-correlation plays a unique role. With the recent development of seismological observation facilities, it has been possible to carry out empirical and theoretical investigation of the concepts and methods related to the identification and use of ‘repeating earthquakes’. This talk summarizes the results we obtained in recent years using the seismological recordings of the Beijing Capital Circle Seismograph Network and the Liaoning Provincial Seismograph Network. Issues discussed include: mixed use of broadband and short-period recordings; identification criterion and network dependence, and details of the ‘repeater multiplet’. We used the ‘repeating events’ to evaluate the precision of earthquake location, study the pre-earthquake accelerating moment release, and measure the healing process associated with the aftershock sequence.

Shape, Winds and Gravity of rapidly rotating Jupiter

Keke Zhang and Dali Kong, Center for Geophysical and Astrophysical Fluid Dynamics and Department of Mathematical Sciences, University of Exeter, UK Xinhao Liao, Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai, China Jerry Schubert, Department of Earth and Space Sciences, University of California, Los Angeles, USA

The Juno spacecraft is now on its way to Jupiter and the Cassini spacecraft will visit Saturn toward the end of its mission. One of the main scientific objectives of the Juno spacecraft is to determine the structure of the zonal winds taking place in the Jupiter's atmosphere by measuring the parameters of Jupiter's gravity field. If the winds of the giant planet are sufficiently deep and strong, they are capable of producing a significant perturbation to its shape and exterior gravitational field. We investigate, via an analytical and numerical method, both the shape and the variation of zonal gravity coefficients of Jupiter caused by its deep zonal winds by assuming that the zonal winds pass through the whole interior of the planet along cylinders that are parallel to the axis of rotation. By taking the oblateness of the rapidly rotating planet into the leading-order approximation, we are able to accurately estimate the changes in low-degree zonal gravitational harmonics that are only induced by the effect of the zonal winds for the rapidly rotating planet.

Evaluation of potential fields generated by Earth’s mass components

Pavel Novák NTIS, University of West Bohemia, Pilsen, Czech Republic

In this contribution spectral formulas for evaluation of the gravitational potential and its selected functionals generated by a closed volumetric mass layer are discussed. General expressions are applied for evaluation of numerical values for topography, bathymetry, continental ice masses and crustal mass layers based on available high resolution global ETOPO and CRUST models describing geometry of the Earth’s surface and mass density variations within upper crustal layers. The methodology and obtained results can be applied to reduction and/or stripping of gravity observables such as GOCE gravitational gradients prior their geophysical interpretations.

Spatial variations in sea level in the near field of melting ice: Effects of Alaskan glacier melting using a spatially realistic load model

Emma M. Hill1,2, James L. Davis3,2, Mark E. Tamisiea4, Rui M. Ponte5, and Nadya T. Vinogradova5. 1 Earth Observatory of Singapore, Nanyang Technological University, Singapore 2 Harvard-‐Smithsonian Center for Astrophysics, Cambridge, MA, USA 3 Lamont-‐Doherty Earth Observatory of Columbia University, Palisades, NY, USA. 4 National Oceanography Centre, Liverpool, UK. 5 Atmospheric and Environmental Research, Inc., Lexington, MA, USA.

Ice loss from glaciers results in highly non-‐uniform patterns of sea-‐level change due to the effects of self-‐attraction and loading. To quantify these spatial effects it is necessary to obtain a model for this ice loss that is both spatially realistic and regionally complete. We demonstrate a technique to produce such a model for the Alaskan glaciers, by combining mass-‐balance rates from a GRACE mascon solution with realistic glacier geometries. This load model can be applied to solution of the “sea-‐level equation” to determine gravitationally self-‐consistent sea-‐level and gravity rates.

Our model predicts a significant drop in relative sea level in the near-‐field of the Alaskan glaciers, with coastal rates of around -‐9 mm/yr (compared to a global average rise of 0.2 mm/yr), and significant differences to those predicted by a coarser model. Importantly, the magnitude and sensitivity of these near-‐field rates imply that the near-‐field tide-‐ gauge records could contain significant information about the spatial distribution of ice loss.

Comparison of model gravity rates with an independently produced, spherical-‐ harmonic, GRACE solution verifies that our technique can successfully capture the mass changes estimated in the mascon solution within our higher-‐resolution model. We also use our ice-‐load model to examine the possibility of detecting the effects of ice loss in estimates of ocean bottom pressure (OBP) from GRACE. We use the model to simulate the effects of GRACE signal leakage, and show that the OBP signal from leakage has a similar pattern, but

larger amplitude, to the sea-‐level “fingerprint” expected from ice loss.

Ocean circulation in Southern Ocean from GOCE gravity model

A. Albertella, R. Savcenko, T. Janjić, R. Rummel, W. Bosch, J. Schröter

A Mean Dynamic ocean Topography (MDT) has been computed using a high resolution GOCE gravity model and a new mean sea surface obtained based on a multi-mission analysis of satellite altimetry and covering the period October 1992 till April 2010. The considered gravity model is a pure GOCE gravity model, computed using 12 months of data. The GOCE gravity data allow for more detailed and accurate estimates of MDT. The calculation of geostrophic velocities from satellite data is now possible with higher accuracy and spatial resolution. In order to assess the properties of the derived geostrophic velocity field, velocities are compared with a recent dataset from satellite tracked surface drifters. The analysis is performed in the area of the Antarctic Circumpolar Current (ACC), which presents particular challenges due to the high temporal variability and the sparseness of the in-situ observations.

On the kinematic positioning of a lunar rover with SBI technology

Erhu WEI, Xuechuan LI School of Geodesy and Geomatics, Wuhan University, 129 Luoyu Road, Wuhan 430079, China [email protected]

SBI (same-beam interferometry) is one of the key technologies in the relative positioning of lunar rover vehicles. In this paper, a lunar tracking model based on Kalman filtering and SBI is introduced. Then, based on the Chinese VLBI (very long baseline interferometry) network, SBI data with a precision of picoseconds is simulated. The lunar rover’s kinematic position is then estimated by the Kalman filter and least squares adjustment, respectively. Finally, the results are presented, which show that the positioning accuracy by Kalman filter is better than the least squares adjustment. Keywords: lunar exploration project; lunar rover vehicle; VLBI; Kalman filter; kinematic positioning

High-resolution constraints on the response to ice load changes in the Antarctic Peninsula and Iceland, using radar interferometry

A. Hooper1, A. Oyen1, A. Auriac2, K. Spaans2, F. Sigmundsson2, M. King3 1 Delft University of Technology, Delft, Netherlands 2 University of Iceland, Reykjavik, Iceland 3 Newcastle University, Newcastle, United Kingdom

In recent years, measurements to constrain glacial isostatic adjustment have come chiefly from GNSS. In areas where there is no longer ice present, this approach usually works well, as networks are generally dense 35 enough to sample the extent of any spatial variation. However, in regions where there is still ice melting today, spatial and temporal variations in the rate of melting can cause spatial variability in the deformation, both elastic and viscoelastic, beyond the resolution of GNSS networks. One way to densify deformation measurements is through interferometric analysis of synthetic aperture radar images (InSAR) acquired from space, which offers a potential spatial resolution of 20m or better, depending on the sensor. The accuracy of single interferograms is degraded by variability in atmospheric propagation, but by processing long time series of images it is possible to deliver accuracies at the mm/yr level between points 10’s of km apart. Here we present examples of time series InSAR analysis from the Antarctic Peninsula and Iceland. In Antarctica the GNSS network is particularly sparse, and GIA models are not well constrained. The presence of many rocky outcrops in the peninsula region makes this a good candidate for InSAR analysis. However, there are several technical challenges that make applying InSAR here difficult: image coregistration can be misled by slow moving ice flows, a regional high resolution elevation model is not available and phase-unwrapping between outcrops separated by ice is not straight forward. Despite these complications, we have created coherent time series using images acquired between 2003 and 2010. Our results show a clear spatial pattern of rebound due to the break-up of the Larsen-B ice shelf and the subsequent accelerated ice flow. In Iceland, rebound from the end of the last glaciation is already over, but retreat of the remaining ice caps since 1890 is causing uplifts of up to 25 mm/yr. Measurements of this effect are complicated by the fact that there is also significant deformation due to volcanic and tectonic processes. We apply time series InSAR techniques to images acquired between 1992 and 2009 and observe differences in uplift velocities both temporally and spatially, even between neighboring outlet glaciers. These two examples demonstrate, on different scales, the limitations of existing measurements to assess the ongoing response to ice load changes, and the feasibility of using InSAR techniques to augment them.

Ground Deformation in the Kyoto Basin and Osaka Plain Detected with SAR Interferometry

Manabu Hashimoto (DPRI, Kyoto University)

We have been conducting an interferometry of SAR images acquired by ALOS/PALSAR and TerraSAR-X to reveal ground deformation and the configuration of basement of the Kyoto basin and the Osaka plain. We have analyzed PALSAR ascending images and applied a 2.5 dimension analysis to the stacked interferograms from both the ascending and descending orbits. We also applied StaMPS to PALSAR images to detect temporal variation in deformation. We analyzed 24 SAR images from the path 414 (frame 680) acquired during the period from October 8, 2006 to October 19, 2010, and 15 images from the path 65 (frame2920) during the period from January 9, 2007 to October 20, 2010. Pairs of images that have as short perpendicular baselines and long temporal intervals as possible were selected for interferometry. After that, interferograms were stacked to obtain average rate of line-of-sight (LOS) changes. During the interferometry, we applied flattening in order to reduce long-wavelength noise, which might have been originated by ionospheric disturbances. We also made analyses of TerraSAR-X images. TerraSAR-X images also gave similar results, which suggests that these observations revealed real ground deformations. In these analyses, we found LOS decrease in southern part of Kyoto basin and LOS increase along the ATTL. Then we applied 2.5 dimension analysis to these stacked interferograms to decompose LOS velocities in two directions into E-W and quasi-vertical components. Finally, we obtained about 1 cm/yr uplift in the southern

part of Kyoto basin and 5 mm/yr subsidence along ATTL. In these areas, we did not recognize notable horizontal components, which suggests that they are purely uplift or subsidence. Interestingly, uplift in Kyoto is bounded by two active faults (Katagihara and Haibara faults). These features are also found in the time series analysis using StaMPS. It is, however, difficult to identify when these deformation started due to relatively large signal-to-noise ratios. It is speculated that changes in groundwater table may affect the ground deformation in the Kyoto basin, since there is a big underground reservoir. Subsidence along ATTL may also be related to change in groundwater level and associated compaction of soil. One possibility is the postseismic effect of the 1995 Kobe earthquake, since the feature of the subsidence is quite similar to that observed during the postseismic period of the 2006 Mozambique earthquake. PALSAR level 1.0 data were obtained from JAXA (Japan Aerospace Exploration Agency) under MEXT’s (Ministry of Education, Culture, Sports, and Science and Technology) research project “Intensive Observation of the Uemachi Fault”. The ownership of PALSAR data belongs to METI (Ministry of Economy, Trade and Industry) and JAXA. TerraSAR-X images were supplied by Pasco Ltd. under the Research Program by the Forum for the Application of SAR Technology. Copyright of TerreSAR-X images belongs to Infoterra GmbH.

Indexing Method for LIDAR Points Cloud Data Based on Spatial Characteristics

Zhipeng Li College of Resource and Environment Graduate University of Chinese Academy of Sciences Beijing, P. R. China [email protected] Xiaomin Du College of Survey Engineering and Geosciences China University of Mining & Technology, Beijing Beijing, P. R. China [email protected]

LIDAR can provide great value in many fields with its massive amounts of data which also constraints its development of applications. Therefore, the efficient organization and management of LIDAR points cloud data is necessary and urgent. This paper presents an indexing method based on the spatial characteristics of the LIDAR data: first divides the data into a regular grid in the horizontal direction; then partitions each grid cell according to density of the point elevation value in the vertical direction, thus irregular hexahedron constructed; finally, creates linked list for the points in each hexahedron. The paper concludes that: the indexing method can manage LIDAR data efficiently and reliably; the building algorithm is simple, efficient and application-oriented.

Key Words: LIDAR; Indexing; Spatial characteristics; Irregular hexahedron

UNSUPERVISED CLASSIFICATION OF DUAL BAND POLARIMETRIC SAR IMAGE USING NON-GAUSSIAN STATISTICAL MODELS

Arnab Muhuri1*, Avik Bhattacharya1 1 Centre of Studies in Resources Engineering, Indian Institute of Technology Bombay, Powai, Mumbai - 400 076, INDIA.

Statistical modeling of images is a crucial and fundamental exercise in computer vision and image processing, and is the cornerstone of many important tasks such as classification, segmentation, compression, detection, and recognition. While processing SAR images there is a strong need for such statistical distribution models which can appropriately model the radar backscattered signal. The multiplicative noise and high dynamics of pixel values in SAR images prevents one from using classical image processing tools. Over a long period of time researchers have assumed the SAR backscattered signal statistics to be Gaussian to make the analysis mathematically lenient. Recently, researchers have analyzed and found that non-Gaussian models symbolize such signals better. Statistical modeling helps us in understanding terrain scattering mechanism. The backscattered clutter statistics provide an indication of the type of surface material present. The presence of a scattering mechanism is prominent in one of the polarimetric channels. In SAR, the illumination is made with a coherent source. The involved signals interfere in a constructive and destructive manner which brings about differences in the backscatter statistics. The statistics varies with the change in the nature of the target, the polarization and also the frequency/band of the signal in which the image is acquired. This work stem from the fact that every class has got a distinct probability distribution model associated with it. Each model is a combination of certain number of parameters put together in a mathematical relationship. In this work we have used both classical (Method of Moments) and Mellin kind statistics (Method of Log-Cumulants) to estimate these parameters. These parameters are then used for qualitative classification by observing the variation in their values and by plotting the estimated cumulants in the Pearson diagram. The parameter set used for final classification is optimized by performing goodness-of-fit tests (Root Mean Square Error, Kolmogorov-Smirnov & Kullback Leibler Test) and by observing the trend in the parameter values for different bands and polarization channels. These parameters are used as a keynote for image classification. A multi-distribution parameter image is obtained and it is then subjected to an unsupervised classification. This study also reveals variation of textural information content across the bands and different polarization channels. We have concluded this work with an attempt to classify dry and wet snow covered areas in short wavelength polarimetric SAR image using the above mentioned technique.

REFERENCE Nicholas, J.-M., 2002. Introduction aux statistiques de deuxieme espece: applications des logs-moments et des logs-cumulants a l’analyse des lois d’images radar, Traitement du signal, vol. 19, no. 3, pp. 139-167. To whom all correspondence should be addressed: E-mail: [email protected]

Bare Surface Scattering Properties Study in order for GNSS-R Applications

Xuerui WuA,B,C Ying LiA

Institute of Environment Information Dalian Maritime University, Dalian Liaoning, 116026, China B. Department of Environment Resources and Management, Chifeng College, Chifeng 024400 China C. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University. Beijing 100875, China

Soil moisture is a critical hydrological variable to study water and carbon cycles. While Satellite missions, such as the ESA soil moisture and ocean salinity (SMOS) mission and the future Soil moisture Active and

Passive (SMAP) observations are planned to measure soil moisture at high time and spatial resolutions. Both are working at the optimal soil moisture monitoring and retrieving L-band. With its so many advantages, GNSS-R provides a good ground based measurement for the above satellite missions’ calibrations and validations. However, as a new promising microwave remote sensing technique, some ambiguities still exist. This paper focuses on the polarization properties and angles (zenith and azimuth) study. Bistatic scattering model advanced integral equation model (AIEM) is used as the study tool after some modifications. Optimal angles and polarizations are studied through lots of theoretical simulations in order for GNSS-R receiver’s design (ground-based or even space borne). However, in situ measurements are needed to further test the conclusions in theory.

Key words: GNSS-R, polarization, angles, AIEM

Correcting Unmodeled Periodical Ocean Tidal Loading at the Observation Level and Its Impact on Continuous GPS Coordinate Time Series

LI Zhao1, JIANG Weiping2, Ding Wenwu3,4, Liu Renli1

1. School of Geodesy and Geomatics, Wuhan University, Wuhan 430079, China; 2. Research Center of GNSS, Wuhan University, Wuhan 430079, China; 3. Institute of Geodesy and Geophysics, Chinese Academy of Sciences, 340 XuDong Road, Wuhan 430077, Hubei, China 4. Graduate University of Chinese Academy of Sciences, A 19 Yuquan Road, Beijing 100049, China

Abstract: Time variable deformation of the earth caused by ocean tides could reach up to 100mm, thus it is very important to do ocean tidal modeling in precise GPS processing. Conventionally, only a discrete set of harmonics in the long-period, diurnal and semidiurnal bands (totally 11 main constituents) are considered to calculate site-dependent ground displacement caused by Ocean Tidal Loading (OTL). However, complete neglecting of the minor tides and nodal modulations with only the 11 main tides may lead to errors of up to 5 mm RMS at high latitude, and could also produce spurious harmonics in GPS time series (especially in the height component), which would lead to incorrect interpretation of geophysical signals. Therefore, it is of great significance to investigate the actual impact of unmodeled periodic OTL on Continuous GPS position time series. Aiming at the insufficiency of the current OTL modeling in GPS precise data processing, this paper realizes the modeling method of unmodeled periodical OTL correction in GAMIT, then reprocesses GPS data of 109 globally distributed IGS stations spanning from mid-1998 to 2010 using the modified GAMIT with state of the art models according to IERS Conventions 2010. Based on it, we quantify the contribution of unmodeled periodical OTL to global GPS coordinate time series, finding that the vertical displacement of GPS stations in ocean and coastal areas caused by unmodeled periodical OTL correction could reach 7mm. Besides, unmodeled periodical OTL correction could not only cause obvious vertical velocity change of most stations(74%), but could also effectively reduce the RMS of most stations’ coordinate time series (76%) in the up and east components, especially for stations near the coast and in the ocean regions. Furthermore, it could significantly reduce the annual amplitude of the East and Up component, semi-annual amplitude of the North component of stations in low latitudes, semi-annual amplitude of the East component of stations in high latitudes, together with semi-annual amplitude of the Up component of stations in middle latitudes. Considering the impact of unmodeled periodical OTL could also remarkably reduce the

periodical signal with cycle at about 352 days of stations in middle-to-high latitude regions, which is in accordance with the abnormal period of 1.04cpy discovered by Ray et al. (2008), thus we propose that the station displacement caused by unmodelled periodical OTL is one of the main geophysical factor that caused the abnormal harmonics with period of 1.04cpy. Results of this paper would provide more accurate data for crustal motion, interpretation of geophysical signals, as well as mm-level reference frame establishment. Keywords: unmodeled periodic OTL; GAMIT/GLOBK; global GPS reprocessing; time series analysis; abnormal harmonics

Study on Seasonal Variations Derived from Vertical Component of GPS Site Position Time Series

Feng Zhou Institute: China University of Mining and Technology(CUMT), China Address: School of Environment Science and Spatial Informatics, CUMT, Xuzhou, Jiangsu 221116, China E-Mail: [email protected]; Tel: 15805217653

In recent decades, space geodesy technique (such as GPS, VLBI, SLR, DORIS) was applied to monitor crustal deformation directly and effectively. Since GPS measurement has advantages of all-weather, easy to operate, easy to move the instruments, substantial ground stations and good geographical distribution, et al., and also the measurement accuracy is roughly the same as VLBI, SLR. Hence, GPS technique is widely applied to observe plate motion and crustal deformation. The paper selected 259 global distributed GPS sites to study on seasonal variations from vertical component of position time series and their geophysical explanation. Firstly, the SOPAC’s loosely constrained GIPSY and GAMIT daily solutions are input as quasi-observations to the Quasi-Observation Combination Analysis (QOCA) software to estimate the time series of site positions. The results show that annual and semiannual variations are consist in east, north and vertical components of GPS site position time series, and the annual variations are more apparent than the semiannual, further, the annual and semiannual variations in vertical compent are more apparent than east and north components. Furthermore, the results of FFT power spectral analysis are consistent with the above mentioned. However, except for annual and semiannual terms, abnormal high frequency periodic terms of integer times of 1.040 cpy (circles per year) are consist in site position time series. Ray et al.(2008) have excluded the effect of atmosphere, soil moisture and snow et al. mass loading, however the source of such periodic terms is not clear and needs further study. Then, the paper analyzes the geophysical explanation of annual terms in GPS site position time series. Since pole tide, solid earth tide and ocean tide have taken into account in SOPAC’s daily solution, hence the paper mainly focuses on the effect of non-tidal ocean mass loading, atmospheric mass loading, snow and soil moisture mass loading which SOPAC has not considered. In recent study, snow and soil moisture mass loading mainly use National Center for Environmental Prediction (NCEP)/Department of Energy (DOE) reanalysis-2 global data, but NCEP/DOE reanalysis-2 data has deficiency and its solutions include jump. Hence, the paper attempts to employ GLDAS’s (Global Land Data Assimation System) snow and soil moisture data into our analysis about seasonal variations. The results show that GLDAS’s snow and soil moisture data can better explain geophysical phenomenon about vertical component of GPS site position time series. Keywords: GPS; crustal deformation analysis; vertical position time series; seasonal variations; FFT power

spectral analysis

Change Detection about Coal Fire Districts by Interpreting with Thermal Remote Sensing

Xiaomin Du, College of Survey Engineering and Geosciences China University of Mining & Technology, Beijing Beijing, P. R. China, [email protected] Zhipeng Li College of Resource and Environment Graduate University of Chinese Academy of Sciences Beijing, P. R. China [email protected] Fang Tian College of Survey Engineering and Geosciences China University of Mining & Technology, Beijing Beijing, P. R. China [email protected]

Abstract—The coal spontaneous combustion in Northwest China not only destroys the coal resources, but also results a huge quantity of greenhouse gases emission into the atmosphere. To calculate the amount of these greenhouse gases, distribution and extension of the coal fire areas must be known firstly. The surface temperature of the coal fire district is obviously higher than the background environment. This makes it possible to analyses it by using thermal remote sensing. This work started with the basic theories of thermal remote sensing, analyzed the common methods of recovering surface temperature from the thermal infrared bands, and made a introduction of the data resource commonly used by the thermal remote sensing. At last, chose two of them to Interpret the surface temperature of Wuda coal fire district. The area of Wuda coal fire was estimated as well. With the statistical data, the result was evaluated appropriately. The modeling tools in ERDAS and thermal module in ENVI were used in the process of Interpretation. The result indicates that the area of Wuda coal fire district is 3,945,600m2 (as to 2010), and the predictive accuracy of using thermal remote sensing is 87.1%. In a large scale, it is feasible to detect the coal fire district using the thermal remote sensing methods. With the methods and algorithms above, the author generates a sequence of coal fire districts in the research fields by extracting high temperature area in multisource remote sensing products and in difference year. This work conveys that with the implementation of national sponsored fire fighting works, the coal fire area was decreasing in last decade. (Abstract) Keywords-component; coal fire, thermal remote sensing, surface temperature Interpreting, TM, ASTER (key words)

A gravity field model from GOCE and Combination with GRACE

Weiyong Yi Institut für Astronomische and Physikalische Geodäsie (IAPG), Technische Universität München, Arcisstr. 21, 80290 Munich, Germany [email protected]

GOCE is the first satellite with a gravitational gradiometer (SGG). This allows determining a gravity field model with high spatial resolution and high accuracy. Four of the six independent components of the

gravitational gradient tensors (GGT) are measured with high accuracy in the so-called measurement band (MB) from 5 to 100 mHz by the GOCE gradiometer. Based on more than 1 year of GOCE measurements, two gravity field models have been derived. Here, we introduce a strategy for spherical harmonic analysis (SHA) from GOCE measurements, with a bandpass filter applied to the SGG data, combined with orbit analysis based on the integral equation approach, and additional constraints (or stabilization) in the polar areas where no observation is available due to the orbit geometry. In addition, we combined the GOCE SGG part with a set of GRACE normal equations. This improves the accuracy of the gravity field in the long-wavelength parts, due to the complementarity of GOCE and GRACE. Comparison with other models and with external data shows that our results are rather close to the GPS-levelling data in well-selected test regions, with an uncertainty of 5 to 7 cm, for truncation at degree 200. Keywords: Satellite gradiometry; Gravity gradiometry; Satellite-to-Satellite tracking; GOCE; Gravity field; Variance component estimation

Melting of ice-sheet in the Tibet confirmed by satellite gravity measurement

Shuanggen Jin1, Guiping Feng1, 2 1 Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China 2 Graduate University of Chinese Academy of Sciences, Beijing 100049, China

Continental ice sheets are frozen from fresh-water with volume change related to the temperature and snowfall, which affect and are affected by changes in Earth's climate. It also plays an important role in global water cycle and understanding land and ocean water exchange and energy balance. The Tibetan Plateau (TP) as “the Third Pole” of the Earth has the largest ice mass except the North and South Polar Regions. Due to recent global warming, some glaciers are melting. However, the glacier in TP has a mean elevation of more than 4000m and it is very difficult to accurately monitor TP ice-sheet variations due to the lack of in situ widespread measurements. With the launch of the Gravity Recovery and Climate Experiment (GRACE) mission since 2002, it was very successful to estimate the varying terrestrial water storage (TWS).The satellite-based GRACE observations provide a unique opportunity to quantify ice-sheet mass variations. In this paper, long-term variations of TP ice sheets derived from 10 years of monthly GRACE solutions (2002-2010) are studied. Results have shown the ice is significantly melting in Himalaya and Kunlun Mountains since 2005, while in some areas in the Tibet, the ice is increasing.

On the Chinese Spaceflight TT&C Network for Tiangong-1

Erhu WEI, Liu CHANG, Hongzhou YANG, Peng WANG (School of Geodesy and Geomatics,Wuhan University,129 Luoyu Road ,Wuhan 430079,China)

Abstract—China has invested enormous effort in manned space engineering. The Tiangong-1 and Shenzhou-8 have been launched, twice rendezvouses have been accomplished successfully. In order to meet the requirements of the manned space engineering on the TT&C network, and prepare for our country’s space station construction on TT&C in the future, two satellites of Tianlian-1 Tracking Data Relay Satellite System have been launched and are running together, and been used for the rendezvous task. In this paper, the efficiency and geometric precision (PDOP) of Chinese Spaceflight TT&C Network Observing Tiangong-1

were calculated and analyzed based on Ground-based TT&C Network and the new TT&C Network included Tianlian-1 Tracking and Data Relay Satellite System respectively according to the Tiangong-1 task. Keywords- TT&C Network, unified S-band system, coverage efficiency, geometric precision, PDOP

The average acceleration approach applied to gravity coefficients recovery based on GOCE orbits Huang Qiang, Fan Dongming, You Wei (Faculty of Geoscience and Environment Engineering, Southwest Jiaotong University, 111 North 1 Section, 2nd Ring Road, Chengdu 610031, China)

Abstract: The average acceleration approach was applied to recover a gravity field model Model_ACA from GOCE precise science orbits between 9.2.2010 and 11.2.2010, and further more a so called sequential least square adjustment was used. The model was compared with other gravity field models based on CHAMP, GRACE, GOCE. The comparison result shows that the model is superior to gravity field based on CHAMP, and with higher accuracy than other international gravity field model based on only GOCE data before 80 degree. The degree geoid height of Model_ACA can reach 3cm up to 90 degree and order. Key words: average acceleration, GOCE, PSO, gravity field

Spatio-Temporal Variations of Water Storage, Precipitation and Evapotranspiration in the Volta River Basin

S. A. ANDAM-AKORFUL*1,2, X. HE1, V. G. FERREIRA1 and J. A. Quaye-Ballard1,2 1. School of Earth Sciences and Engineering, Hohai University, Nanjing 210098, P. R. China 2. Department of Geomatic Engineering, College of Engineering, Kwame Nkrumah University of Science and Technology, Ghana

We investigate terrestrial water storage (TWS) variations within the Volta river basin and its correlation with precipitation and evapotranspiration using global datasets as the basin is poorly gauged. Monthly datasets from the Gravity Recovery and Climate Experiment (GRACE) mission and the Global Land Data Assimilation System (GLDAS) have been used from April 2002 to February 2012 is employed. Multiple Linear Regression Analysis and Kriging is used to determine the spatial and temporal variability of each dataset as well as their relative distributions. Results indicate a gradual increase in water storage within the basin for the period of study. The year 2006 is found to be the period with the highest reduction in water storage, preceded by low precipitations in 2004 and 2005. Conversely, 2010 experienced the maximum gain in storage preceded by high continuous precipitation rates from 2008. Spatially, storage increases gradually from the upper part of the basin to the lower parts. Additionally, a significant correlation between the TWS, precipitation and evapotranspiration is existent at the annual and inter-annual time scales. Keywords: Terrestrial Water Storage Changes, GRACE, GLDAS, precipitation, evapotranspiration, regression

Statistical analysis of ionospheric TEC day-to-day variability

Shun Zhang

School of Geodesy and Geomatics, Wuhan University, 129 Luoyu Road, Wuhan 430079, China

Abstract: In this paper, the TEC data observed by GNSS stations were used to study day-to-day variability of ionospheric total electron content (TEC). The data time span was from 2000 to 2011(one complete solar cycle). According to the geomagnetic latitude, the global ionosphere was divided into high-latitude, mid-latitude and low-latitude, and the TEC variability of these areas were studied under different solar and geomagnetic conditions, respectively. Statistical methods were used to analyze the TEC day-to-day variability caused by different factors, which present better understanding of ionosphere regularity. The results showed that, the TEC had different variation characteristics at different latitudes and space environmental conditions. Under quiet geomagnetic conditions (Kp < 1), the standard deviation of TEC about the mean at day time is approximately ±15%, at night time is ±25%, and it is the same at all latitudes. For disturbed conditions (Kp > 4), TEC variability at day time is approximately ±35% at low-latitude, ±45% at mid-latitude, ±55% at high-latitude. During night time this indicators were ±40% to ±60%. The greater percentages at nighttime were because small changes in TEC resulted in large percentage changes when reckoned with respect to low nighttime mean values. Finally, the theoretical models of the ionospheric day-to-day variability were discussed. Keywords: ionosphere; TEC; variability; GNSS

Diurnal Variation of Ground-based GPS-PWV under Different Solar Radiation Intensity in Chengdu Area

Jiaona Chen1,2, Guoping Li 1* (1 College of Atmospheric Sciences, Chengdu University of Information Technology, Chengdu 610225, China) （2 Xiamen Bureau of Meteorology, Xiamen 361012,China） * Corresponding author: LI Guoping, E-mail: [email protected]

Abstract: The estimates of total zenith delay are available based on GPS data from the ground-based GPS of Chengdu station by using GPS analytic software package. The estimates of every 30min precipitable water vapor (PWV) derived from GPS are obtained by combining meteorological data from automatic weather stations. Combined with day data of solar radiation and sunshine, the character of GPS-PWV in the strong and weak solar radiation is analyzed. The relationship of GPS-PWV with surface temperature in strong and weak radiant intensity is researched. It showed that the GPS-PWV of weak radiation is higher than strong radiation, and the relation between PWV and Q is positive correlation. Without considering the rainfall, the difference of GPS-PWV in strong and weak radiation day respectively appears in the daytime. In the daytime △ △ of strong radiation day（fine day）, GPS-PWV is negative correlation to temperature. The main decreasing period of GPS-PWV is behind sunrise, and while temperature is maximum, the GPS-PWV is minimum. In daytime of the weak radiation day (overcast), the relation of GPS-PWV and temperature is lag positive correlation. With the increasing of the temperature as well as GPS-PWV, the variation of GPS-PWV is lag to the variation of temperature for the greenhouse effect of water vapor. Key: ground-based GPS; precipitable water vapor; radiation intensity; diurnal cycle.

NEAR - REAL TIME ZTD MODEL FOR THE AREA OF POLAND

J. Kaplon, T. Hadas, J. Bosy, J. Sierny and K. Wilgan

Institute of Geodesy and Geoinformatics, Wroclaw University of Environmental and Life Sciences, Grunwaldzka 53, 50-357 Wroclaw, Poland [email protected] tel.: 0048-713205682 fax.: 0048-713205617

Precise positioning requires the introduction of a'priori precise orbits and satellite clocks information to the equation system. The use of dual frequency GNSS receivers eliminates the first-degree influence of the ionosphere by means of using the linear combinations of the observations. During post-processing, introduced a'priori models can be corrected during the estimation process, but when determining the position in real-time used models must be as precise as possible. An important problem is the introduction of reliable tropospheric delays especially for the PPP-RTK solutions. This requires the real-time service providing actual ZTD products on the area of interest. Another important application of ZTD from GNSS monitoring is the estimation of the water wapour content in the atmosphere. Difference between ZTD derived from GNSS observations and Zenith Hydrostatic Delay (ZHD) obtained from empirical models of troposphere, results with the Integrated Water Vapour (IWV) product. Evolution of models of the troposphere allows increasing of temporal and spatial resolution and the transition from standard atmospheric models to models of weather parameters distribution, which can be derived from numerical models such as weather forecasts or meteorological stations networks.

Presented studies show the procedure of ZTD estimation for the area of Poland, based on the GNSS data from ASG-EUPOS and EPN networks, and show the quality assesment of the near-real time ZTD products coming from the: double diffference L3 fast solution (without ambiguity resolution), double-difference L5/L3 solution, PPP solution, Saastamoinen model, calculated using temperature, air pressure and relative humidity real measurements, using the EPN ZTD estimates as the reference for comparison.

Numerical Simulations of Earthquake Fault Systems for Earthquake Physics, Forecasting, and Geodetic Data Analysis

John B Rundle Departments of Physics and Geology University of California Davis, CA, USA

Earthquake fault systems are complex nonlinear systems, analogous in principle to weather and climate. Understanding these catastrophic events requires an understanding of the complex physics that underlie these 45

driven threshold systems. Simple models are not adequate. For example, the official California earthquake forecast produced by the Working Group on California Probabilities is used to set earthquake insurance rates in California. The current model-building committee is moving towards making more extensive use of numerical simulations of complex interacting fault systems to produce the next generation fault model (“UCERF”). One of these simulations is Virtual California, which is designed to help analyze the behavior of fault systems over long time periods. The simulation uses friction laws together with geologic data on rates of slip along major faults. Boundary element methods are used to compute stress Green’s functions for dipping faults. These simulations can be computationally intensive due to the stress calculations that occur during long term fault movement and the multiple rupture propagation calculations that occur during each earthquake. In order to properly handle fault models with fine-scale resolution, we parallelized Virtual California using MPI to run in compute clouds. Here we discuss the state of VC and its prospects for not only understanding earthquake physics, but also in forecasting larger earthquakes. We also show how these types of numerical simulations can be useful in understanding space geodetic data such as GPS and InSAR observations. As these data become increasingly abundant, frequent and reliable, simulations will be needed for data assimilation and analysis. We find that the simulations are becoming increasingly more realistic, as shown by improving comparisons to field paleoseismic data and instrumental data. Pattern analysis methods have been developed that rely on detecting correlations in model time series. We also discuss the prospects for use of the models in forecasting. We also discuss the relationship of such numerical simulations to other types of earthquake forecasting methods, for example, based on the use of seismic catalog data to understand patterns of earthquake activity and from there compute future earthquake probabilities. These methods are complementary to numerical simulations, in that they typically sample a different data set. For that reason, they are already providing a guide to geodetic observations in southern California, e.g., InSAR data derived from UAVSAR flights. We discuss this project and show preliminary results.

Co-seismic Deflection Change of the Vertical Caused by the 2011 Tohoku-Oki Earthquake (Mw9.0)

Wenke Sun and Xin Zhou Key Laboratory of Computational Geodynamics, Graduate University of Chinese Academy of Sciences, China, e-mail: [email protected]

This paper presents a scheme to compute co-seismic deflection change, and presents a set of Green’s functions for four independent dislocation sources. To compare the theoretical deflection changes with the GRACE-observed ones, the dislocation Love numbers are truncated and the Green’s functions are computed with application of a Gaussian filter. Using this computing scheme, the modeled co-seismic geoid and deflection changes can be compared directly with the GRACE-observed ones. Numerical computation and comparison show that the computing scheme is valid and efficient, and that it can obviate much unnecessary computing time for high-degree Love numbers. This study further examines the problem of seawater correction to modeled geoid and deflection changes because it is an important and necessary step to compare the modeled results with GRACE-observed deformations. As an application of the dislocation theory and the computing scheme described as a result of this study, we consider the 2011 Tohoku-Oki earthquake (Mw9.0)

using three different fault slip models. Using the fault models, we compute the co-seismic geoid and deflection changes for an area around Japan, considering seawater corrections. Results indicate that the co-seismic geoid and deflection changes can be detected clearly by GRACE observation, and the co-seismic geoid change is not sensitive to the fault slip models: the three slip models yield identical co-seismic geoid changes; whereas the co-seismic deflection changes are very sensitive to the fault slip models because the modeled deflection changes indicate pretty large difference, especially for the E–W component. These behaviors provide us a new and useful approach to invert seismic faults using GRACE-observed deflection changes as constraints.

Creation of strain maps from velocity field of deformation by on-line tools

Milan TALICH, Institute of Information Theory and Automation, Prague, Czech Republic [email protected]

Key words: deformation analysis, displacement vectors, mechanics of continuum, strain maps, velocity field

The paper shows how to a create strain maps from a velocity field or repeated geodetic measurements by appropriate on-line tools and explain why applying of the theory of continuum is useful to deformation analyses obtained from repeated positional survey in geodesy. The independency of resulting deformation parameters to applied coordinate frame is shown, too. By correct processing of repeated geodetic measurements the errors originated from erroneous pre-requisites about stability of some selected points that are taken during normal calculation as stable (in the stable part of such location) will be completely eliminated. When compared to the sole listening of displacements then the strain maps enable to present deformation parameters in much more objective way and serves as a tool to demonstrate the relatively geodynamical trends of the territory in question.

Coriolis-induced state-rate law and strain energy function in coseismic rupture

B.J.Zhu1, 2, X.Y.Liu1, 2, S.H.Yang.1, 2, H.H.Cheng1, 2, C.Liu1, 2,3, Y.L.Shi1, 2 1Key Laboratory of Computational Geodynamics of Chinese Academy of Sciences, Beijing 100049, China 2College of Earth Science, Graduate University of Chinese Academy of Sciences, Beijing 100049, China 3Laboratoire De Geologie, Ecole Normale Supérieure, 24 Rue Lhomond, 75231 Paris CEDEX 5, France

The Coriolis effect in the coseismic rupture processes is explored in this work through the study of the Coriolis-induced transient state-rate law and the Coriolis-induced dynamic strain energy function. First, the Coriolis-induced transient friction coefficient (CI-TFC), the Coriolis-induced coulomb stress increment (CI-CSI) and the Coriolis-induced dynamic strain energy function (CI-DSEF) in the multi-coupled electromagnetothermoelastic (MC-EMTE) wave fields, which includes the crack surface energy, seismic kinetic energy and heat friction energy fields, are obtained based on the MC-EMTE wave field general continuum equation and the wave-time domain Green function. Next, using the earthquake catalogue data

47 from the Harvard centroid moment tensor, the national earthquake information center and the Chinese earthquake administration, the CI-TFC, CI-CSI and CI-DSEF are calculated. In addition, the relationship among the CI-TFC, CI-CSI and CI-DSEF is discussed. Keywords: Coriolis-induced transient state-rate law, Coriolis-induced coulomb stress, Coriolis-induced dynamic strain energy function, coseismic rupture processes, earthquake triggering- early warning system.

Present-day 3D crustal movement in the Qinghai-Tibetan Plateau from GPS data

Caijun XU1, Kaihua DING1,2 ,Qi Wang2 1 School of Geodesy and Geomatics, Key Laboratory of Geospace Environment and Geodesy, Ministry of Education, Wuhan University, 129 Luoyu Road, Wuhan, 430079, China, [email protected] 2 Chinese University of Geosciences,Wuhan, 430074, China

3D displacement rates of GPS monitoring sites in Qinghai-Tibetan Plateau are inferred from seven repeated GPS observation data, which were collected in 1993, 1995, 1997, 2000, 2002, 2007 and 2009 separately. GPS monitoring sites are cross the Kunlun faults, the Karakorum-Jiali faults, the Yarlung-Zangbo suture and Yadong-Gulu rift. According to the location of these sites, and the tectonic background of the plateau, the movement of the sub-blocks is analyzed. Based on the analysis of the movement, some meaningful results are obtained. The strategy of some experts about dividing the sub-blocks in the plateau is adopted, there are sites GOLM (Golumd), WT02 (Budongquan), WT03 (Erdaogou), WT04 (Yanshiping), WT05 (Wenquan), ANDU (Anduo), SOXI (Soxian), WT07 (Naqu) and LHS2 (Lahas) in Tibetan sub-block, and sites WT09 (Ganzi), LAZE (Lhaze), WT11 (Nyalam), WT12 (Saga), WT13 (Xigaze) and WT15 (Yadong) in Himalayan sub-block (Liu et al., 2000; Zhang et al., 2004). With reference to the Eurasia plate, the horizontal velocity of site LHS2 is 23.3±0.4 mm/a, which is different from Liu’s result (29.8±1.5 mm/a) (Liu et al., 2000), but consistent with Zhang’s result (25.1±1.8 mm/a) (Zhang et al., 2004). The reason for the difference may be that only three-period repeated surveying was processed, with less accurate orbits in early years. Provided that the velocity of the IGS site IISC (Bangalore) represents the subduction velocity of the India plate, the convergence rate of India-Asia collision is 19.0±0.5 mm/a, which is consistent with Liu’s result (19.5±1.7 mm/a) (Liu et al., 2000), Zhang’s result (17±3 mm/a) ( Zhang et al., 2004)), and the result (18±7 mm/a) got by seismic and geological data (Aarmijo et al., 1986). Similarly, the shortening rate of the Tibetan sub-block in NS direction, represented by the velocity difference of site GOLM and LHS2 in NS direction, is 9.1±0.6 mm/a, which is agree with Liu’s result (9.3±4.6 mm/a) (Liu et al., 2000). The EW extension of the plateau mainly occurs at the central part of the Tibetan sub-block. With relative to site GOLM, the average EW extension rate of the other sites in the sub-block is 8.5±0.7 mm/a, which is consistent with Liu’s result (8.7±6.4 mm/a) (Liu et al., 2000), Jiang’s result (11.2±0.2 mm/a) (Jiang et al., 2008), and Armijo’s result (10±5 mm/a) (Aarmijo et al., 1986), inferred from the secular average velocity of active faults.

Figure 1. Present 3D velocity of GPS monitoring sites in Qinghai-Tibetan Plateau, with relative to the Eurasian plate. Red arrows and white arrows represent the horizontal and vertical velocity of the sites, separately.

Except for sites WT05 and WT15, the vertical velocities of the other sites show that the plateau is ongoing rising. Site WT05 is very close to the Qinghai-Tibet Highway, and may be subsiding with the settlement of the highway. As for WT15, it has been surveyed only for three times, and in early years, so the vertical velocity with low accuracy is not reliable. Sites WT02, WT03 and WT13 are under the same circumstance. Except for these sites, the average vertical velocity is 3.2 mm/a, which is slower than Jiang’s result (4~5 mm/a) (Jiang et al., 2008). In order to obtain more information about the monitoring faults and sub-blocks, we use other results and our results together to do the inversion.

Figure 2. Present horizontal velocity of GPS monitoring sites in Qinghai-Tibetan Plateau, with relative to the Eurasian plate. Red arrows are the results from our monitoring sites, and blue arrows are the other results from some articles published. Later on, we will calculate the strain rates of the sub-blocks, and calculate the opening rate of Yadong-gulu rift, the slip rate of Yarlung-Zangbo suture, Karakorum-Jiali fault, and Kunlun Fault. References Liu J.N., Xu C.J., Song C.H., Shi C., Jiang W.P., et al., 2000, Present-day crustal movement and deformation in the Qinghai-Tibetan Plateau by GPS, Chinese Science Bulletin, 45(24): 2658-2663. Zhang P.Z., Shen Z.K., Wang M., Gan W.J., Roland B., et al., 2004, Continuous deformation of the Tibetan Plateau from GPS data, Geology, 32(9): 809-812. Aarmijo R., P. Tapponnier, J. L. Mercier, and H. Tong-Lin, 1986, Quaternary extension in southern Tibet: Field observations and tectonic implications, J. Geophys. Res., 91(B14): 13803-13872. Jiang W.P., Zhou X.H., Liu J.N., and Xu C.J., 2008, Present-day crustal movement and strain rate in the Qinghai-Tibetan Plateau from GPS Data, Acta Geodaetica et Cartographica Sinica, 37(3): 285-292. Chen Q.Z., Freymueller J.T., Yang Z.Q., Xu C.J., Jiang W.P., et al., 2004, Spatially variable extension in southern Tibet based on GPS measurements, J. Geophys. Res., 109, B09401, doi:10.1029/2002JB002350. Gan W.J., Zhang P.Z., Shen Z.K., Niu Z.J., Wang M., et al., 2007, Crustal motion within the Tibetan Plateau inferred from GPS measurements, J. Geophys. Res., 112, B08416, doi:10.1029/2005JB004120. Li Q., You X.Z., Yang S.M., et al., A precise field of tectonic deformation in China as inferred intensive GPS observations, Sci. China Earth Sci., 2012, 55: 695-698.

Inversion for the spatial distribution of afterslip following the 2007 Mw 8.4 Bengkulu earthquake in Sumatra, using a principal component analysis-based inversion method (PCAIM) of SuGAR GPS time-series data

Louisa L.H. Tsang, Emma M. Hill, Lujia Feng, Paramesh Banerjee, and Kerry Sieh

Rupture of the southern portion of the Mentawai section along the Sunda megathrust produced the 2007 Mw8.4 Bengkulu earthquake. The northernmost updip region of the 2007 coseismic rupture area subsequently ruptured on October 25, 2010, producing an Mw 7.8 tsunamigenic earthquake. The spatial proximity of these two earthquakes begs the question: to what extent did the 2007 Bengkulu earthquake trigger the 2010 Pagai earthquake? And if so, by what physical process? GPS timeseries data from the SuGAR (Sumatran GPS Array) reveal that a substantial amount of afterslip occurred following the 2007 mainshock rupture. To explore the role of afterslip processes in releasing and redistributing stress along this section of the megathrust, we estimate the spatial distribution of afterslip during the period subsequent to the 2007 Bengkulu earthquake, using a principal component analysisbased inversion (PCAIM; Kositsky and Avouac, 2010) method. The robustness of the inversion results is quantified by testing over an extensive range of fault and inversion parameters, including fault geometry and discretization size. We have thus far modeled the spatial distribution of afterslip during a ~ 5 month period following the 2007 mainshock, although the entire length of the time-series extending up to the time of the 2010 Mw 7.8 Pagai earthquake will eventually be modeled. Our preliminary collection of model results estimate the equivalent moment magnitude of afterslip to range between Mw 8.0 to 8.2, and reveal peak amounts of afterslip (0.9 to 4.2 m) concentrated updip of the 2007 coseismic rupture area. In order to better understand our model solutions, we will perform further resolution tests and test models which are based on the propagation of coseismic stress changes from the 2007 mainshock.

Moderate-to-Large Earthquakes at the Sumatran subduction zone observed by the Sumatra GPS Array (SuGAr)

Lujia Feng ([email protected]), Emma M. Hill, Paramesh Banerjee, Ashar Muda Lubis, Qiang Qiu, Kerry Sieh Earth Observatory of Singapore, Nanyang Technological University, 50 Nanyang Avenue, Block N2-01a-15, Singapore, 639798

The continuous Sumatra GPS Array (SuGAr) was initiated in 2002 with 6 stations south of the equator. It has recently been expanded to nearly 50 stations covering the Islands offshore Sumatra from Simeulue to Enggano, the western coast of Sumatra, and parts of the Sumatran fault. The long observation time and wide coverage of the SuGAr network provides us with an incredible wealth of data that records the activities on the Sumatran subduction zone. The time series of SuGAr are dominated by large coseismic and postseismic signals from three devastating major earthquakes with magnitudes larger than 8 (the 2004 Mw 9.2 Sumatra-Andaman earthquake, the 2005 Mw 8.6 Nias-Simeulue earthquake, and the 2007 Mw 8.4 Bengkulu earthquake). Besides these extraordinarily large earthquakes, the SuGAr network also records hundreds of smaller but more frequent moderate-to-large earthquakes with magnitudes ranging from 4 to 8. Instead of focusing on the largest earthquakes, we compile a database of moderate-to-large earthquakes that were recorded by the SuGAr network. For each earthquake in the database, we list the distribution of stations that observed the earthquake, and the estimated offsets and/or postseismic parameters estimated for these stations. The results provide an invaluable spatial and temporal earthquake database for studying the dynamics of the Sumatra subduction zone. Using this database, we seek to better understand the physical properties of the subduction interface and the relationship between major and moderate-to-large earthquakes. Removing the earthquake signals also allow us to search for transient rate changes or slow-slip events.

Ocean Tide and Ocean Loading Models of the Yellow Sea

Sung-Ho Na, Jeongho Baek, Byung-Kyu Choi, Seok Lee

Ocean tide in the Yellow sea shows large amplitude and diverse character. A review of pre-existing ocean tide models of the Yellow sea area as well as ocean loading models of the Korean peninsula is made. A new ocean loading model of Korea is constructed by combining local ocean tide model and global ocean tide model using the load Green’s function for the ISAPEI earth model.

Support Vector Machine Aided Extended Kalman Filtering Algorithms for GPS/INS Integrated Navigation

Xinglong Tang, CUMT, Xuzhou, China

Abstract: Aiming at the possible faults of loosely-coupled GPS/INS integrated navigation, a support vector machine-assisted extended kalman filter of the integrated navigation algorithm is put forward. The algorithm overcomes the impact of integrated GPS/INS filter algorithm by the observation error, automatically adjusts the covariance matrix of the observational information based on support vector machine, thereby balances the contribution of the dynamic model of observational information on the navigation solution, and especially can reasonably predict the navigation results when GPS outages occured. It is shown , by comparison and analysis , that the new algorithms can not only weaken the impact of the observation information with error to filter and avoid the influences of faults on the navigation results , but also improve the accuracy of navigation solutions during GPS outages.

Seasonal variability of Global Earthquake Occurrence

Sung-Ho Na, Jeongho Baek, Pil-Ho Park

The Northern and Southern hemispheres each undergo slight seasonal deformation due to winter mass accumulation. To test a hypothesis that this surface loading leads to a seasonal bias in earthquake occurrence, we examined earthquake records from sites in both hemispheres, including a thousand-year long Korean record, and found that a bias in earthquake occurrence does indeed correlate with a seasonal loading cycle. Further, we discovered that certain mid to low latitude regions with other patterns of seasonal hydrologic loading (e.g. monsoonal) display corresponding biases in earthquake occurrence.

Fig. Monthly occurrence of earthquakes in different regions. A: Korean historical earthquakes. Total 1380 earthquakes were recorded during nine hundred years between AD 1012 and 1904. Two bars represent ±95% significance level. B: Recent Korean earthquakes recorded instrumentally between 1978 and 2011. Total 562 earthquakes of magnitude over 2.5. C: Arctic cap area earthquakes (USGS, 1973~2011). Earthquake magnitudes larger than 3, occurred in a spherical cap area of latitude over 60 degrees. D: Antarctic cap area earthquakes (USGS, 1973~2011). Earthquake magnitudes larger than 3, occurred in a spherical cap area of latitude over 60 degrees.

Analysis of tides in Shahid Rajaee Port buoys using integrated least squares harmonic constituent and Fourier series in simplified Geo-database

Abbas Abedini1 and Nasser Najibi2, 3 1 Department of Surveying and Geomatics Engineering, Faculty of Engineering, University of Tehran, Tehran, Iran 2 Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China 3 Graduate University of Chinese Academy of Sciences, Beijing 100049, China E-mail: [email protected], [email protected]

Monthly and yearly predictions of ocean tides are the main pre-study for building any marine structures; otherwise the construction management procedures might not led to successfulness. Tide essentially vertical rotation with period of the medium sea level by 12 and 4 hours (or 24 and 8 hours in some places) has the same basic phenomenon of tidal flow in horizontal rotation. They are essentially linked together as a part of the same phenomenon in causing tidal forces of moon and sun arise. In this paper, we demonstrate that tidal

least squares harmonic constituent and Fourier series solution can provide us with daily, monthly and yearly tidal curves. In order to have both the independent and dependent time variation analysis clearly; a simplified Geo-database in MATLAB documentary is suggested. For this study, four series of data from Shahid Rajaee Port buoys have been chosen; Band-Abbas City, Kangan port, Deylam pier and Bushehr port. We also discuss the precision of our prediction for Chart Datum (CD) and Mean Sea Level (MSL) values in overall method and single-by-single method as Fourier series solutions to apply least squares harmonic constituent (with Nodal corrections and without corrections). Finally, the daily, monthly and yearly tidal curves (frequency and amplitude) with predicted tide components are displayed in a simplified interface Geo-database platform. KEYWORDS:Tide prediction, Tidal curves, Geo-database, Fourier series, Chart datum.

Overview on modern surveying adjustment and theory of data processing

Jianjun Zhu Abstract: This report introduced the relationship between the theories in modern surveying adjustment and the traditional surveying adjustment. It pointed out that the theories of modern surveying adjustment and data processing still based on Gauss-Markov error model. Through enlargement and development in different aspects of the model, new theories and methods are worked out. A figure showing such relationship is given. Meanwhile, new theories and methods of modern surveying adjustment and data processing are introduced in the report. At last, main theories involved in modern surveying adjustment and data processing are summarized.

On the Search Algorithm of Independent baselines for GNSS Data Processing

Erhu WEI, Hongzhou YANG, Yufeng GU School of Geodesy and Geomatics,Wuhan University,129 Luoyu Road ,Wuhan 430079,China

ABSTRACT：In this presentation, six ways used in search algorithm of independent baselines and Program are introduced. Then several search methods of independent baselines are acompared with examples. The right of the baseline is taken into account by many factors, determined by baseline length, baseline precision and relative to baseline. Finally the adjustment results are analyzed. Keywords:Prim algorithm; Kruskal algorithm; correlation matrix algorithm; right matrix

GRACE Detection of water storage variation in Africa and its response to climate events

Ayman A. Hassan1, 2, Shuanggen Jin1 1Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China 2Graduate University of Chinese Academy of Sciences, Beijing 100049, China

The available data are an important step for hydrological modeling and water source management in the world. Unfortunately, the in situ observations with the right characteristics are very sparse globally. Satellite remote

sensing data may overcome current limitations. The current Gravity Recovery and Climate Experiment (GRACE) satellite mission provides unique observations of variations in the Earth’s gravity field with monthly intervals and spatial resolution of several hundred km, theoretically reflecting the terrestrial water storage (TWS) variations in the land. Depending on topographic and climatologic conditions, terrestrial water storage (TWS) variability is mainly dominated by ground water, soil moisture, surface water, and/or ice/snow. Since extremely climate events occurred recently (e.g., drough) and large deserts exist in Africa, the hydrological cycle is very complex in Africa. In this paper, the terrestrial water storage (TWS) in Africa is retrieved from GRACE for 2002 August-2011 May and its variations are investigated at the seasonal and secular scales, which are compared with the Global Land Data Assimilation System (GLDAS) model. Significant terrestrial water storage variations are found in Africa, and most of them are consistent with GLDAS estimates. The weaker signals of terrestrial water storage variations are found in North Africa, located in larger desert areas. The significant anomalies in other parts are affected by the recent extremely climate events, e.g., drought mid-eastern Africa in 2007. In the near future, it needs to further estimate and investigate ground water variations and confirm their responses to the climate events. Keywords: GRACE; Terrestrial water storage; Drought; Africa

Tsunami modeling of a historical giant submarine landslide offshore of Brunei

Qiang Qiu1,2, Emma M. Hill1,2, Adam D Switzer1,2 1Earth Observatory of Singapore, Nanyang Technological University, Singapore 2Division of Earth Science, Nanyang Technological University, Singapore

Submarine landslides, which are a mass failure of sediment, can trigger significant tsunami, putting coastal cities directly facing the submarine landslide at high risk. For example, a tsunami that hit Papua New Guinea in 1998 is thought to have been generated by a submarine landslide, with a measured tsunami height along the coast of PNG of up to 15 meters. This event killed more than 2000 people, and was thought to be the worst death toll from tsunami in the 50 years preceding the 2004 Indian Ocean tsunami. Recently, a giant historical submarine landslide was found offshore Brunei based on high-resolution 3D seismic data [Gee et al., 2007]. The detailed 3D seismic data shows that a giant mass failure occurred, with a volume of 1200 km3 and an area of about 5300 km2. This mass failure started at a water depth of 200 m in the Baram Canyon and extended for about 120 km to the deep basin floor of the North West Borneo Trough. We will present a simple tsunami model based on this giant submarine landslide, and discuss model results for tsunami height along the margins of the South China Sea. Preliminary results from this simple model indicate that tsunami runup on the Brunei coast was >20 m. At Singapore, maximum runup may have been two meters. Our work highlights the fact that although there are some areas of the SE Asia coastline that may be at lower risk from earthquake-generated tsunami, significant risk remains in the form of landslide-generated tsunami.

Snow depth and ice thickness in North Canada retrieved from GPS code-phase difference multipath signals

Nasser Najibi1, 2 and Shuanggen Jin1 1 Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China 2 Graduate University of Chinese Academy of Sciences, Beijing 100049, China

Snow depth and ice thickness play a critical role in the climate change and hydrologic cycle. However, the traditional instruments are very difficult to monitor global high temporal-spatial snow/ice thickness and its variability without a comprehensive global monitoring network due to high cost and hard labor intensity. In this paper, the ground Global Position System (GPS) measurements are proposed to retrieve snow depth and ice thickness variations. The direct GPS signals from the satellites and the reflected signals from the ground can provide us useful information about the land-surface characteristics. In order to obtain the reflected surface features and estimate snow depth and ice thickness, the multipath signals are extracted from GPS Code-Phase Difference (CPD) . The ambiguity of GPS’s CPD is resolved using the modified LAMBDA method and then the obtained multipath frequency peaks are converted into the snow depth and ice thickness. Here, the ground GPS stations are chosen in NorthCanada (Baker Lake ground stations) with snow in most time of the year. The snow depth and ice thickness are obtained at these chosen GPS stations, which are compared with weather forecasting model data. In addition, the effects of time series analysis methods are investigated and discussed as well as the possibility of inferring conditions of the snow layers and dry snow using sudden variations of multipath effects. KEYWORDS:Multipath effects, Snow depth, ice thickness, Code-Phase Difference (CPD).

Response of ionospheric total electron content to super-intense geomagnetic storms: An investigation with dual frequency GPS observation data at IIT Bombay, Mumbai, India

Sampad Kumar Panda1*, Shirish S. Gedam2 1. Centre of Studies in Resource Engineering, IIT Bombay, Mumbai - 400076, India 2. Centre of Studies in Resource Engineering, IIT Bombay, Mumbai - 400076, India E-mail: [email protected] Contact info: +91-9757031298

Geomagnetic Storms are geomagnetic field disturbances usually occur less frequently but may influence ionospheric electrons and particle population, consequently causing potential threat to Space and Earth communication as well as Navigational system applications. The free electrons in ionosphere disrupt the Global Positioning System (GPS) satellite signals delaying velocity; as a result, users may miss their exact locations during positioning measurements. A time delay of 1 nanosecond approximately corresponds to 2.85 TECU (1 TECU = 1 x10^16 electrons/m^2). With the opportunity of full constellation of GPS satellites wrapping the globe, now it has become possible to inspect global even regional ionosphere from the signature stamps upon all satellite signals. The characteristic of the ionosphere is determined by the Total Electron Content (TEC) i.e., the line integral of the free electron density along the pathway of signal, as estimated from simultaneous carrier phase and pseudorange observations on both the frequencies (L1=1575.42 MHz & L2= 1227.60 MHz) of dual frequency observation. The present paper describes observation and analysis of dual frequency GPS data taken from a low latitude permanent GPS station at Indian Institute of Technology Bombay, Mumbai, India (Geographic, 19.13256° N, 72.91623° E; Geomagnetic, 10.78° N, 146.70° E) to study the TEC responses during super-intense Geomagnetic storms through the years 2003 to 2005. Taking together of the epoch-wise estimated TEC of all satellites, the 2-sigma iterated mean TEC value is calculated 56

at every 0.1 hr interval and plotted against time (UT). The maximum value of mean vertical TEC (VTEC) estimated in terms of TECU from the GPS observables are ~132.4 on 29th October (Disturbance storm index in nano tesla, Dst = -353 nT) and ~92.9 on 20th November (Dst = -383 nT) of the year 2003. Similarly, the estimated TEC on 7th November (Dst = -374 nT) and 9th November (Dst = -263 nT) of the year 2004 are overblown to ~63.7 and ~83.3 units respectively. The super storm during 15th May 2005 (Dst = -247nT) also resulted an increased TEC value of ~81.6 units. The consequences of TEC variation is correlated with Advanced Composition Explorer (ACE) spacecraft's recorded 4-minute averages interplanetary magnetic field component (IMF-Bz) and 3-hourly geomagnetic K-indices (Kp-index) to analyze the Super-intense storm effect and its abnormal variation due to interaction between IMF and geomagnetic field. The anomalous behavior of TEC during the occurrence is compared to previous and successive quiet days to estimate its influence during positioning measurements. Keywords: Geomagnetic storm, Global Positioning System, Ionosphere, Total Electron Content

4. Participants List

NO. NAME AFFILIATION COUNTRY EMAIL

1 Arnab Muhuri Indian Ins. Tech. India [email protected]

2 Thomas P. Yunck GeoOptics Inc. USA [email protected]

3 Guiping Feng SHAO, Shanghai China [email protected]

4 Suriya K. Tatevian Institute of Astronomy RAS Russia [email protected]

5 Michael Bevis Ohio State Uni. USA [email protected]

6 Rui Jin SHAO, Shanghia China [email protected]

7 Roland Klees Delft Uni. Tech. Netherlands [email protected]

8 Nasser Najibi SHAO, Shanghai China [email protected]

9 Emma Hill Nanyang Tech. Uni. Singapore [email protected]

10 Shuanggen Jin SHAO, Shanghai China [email protected]

11 John Rundle Uni. California, Davis USA [email protected]

12 Ayman A. Hassan SHAO, Shanghai China [email protected]

13 Zuheir Altamimi IGN, Paris France [email protected]

Czech 14 Pavel Novak Univ. West Bohemia, Pilsen, [email protected] Republic

15 Konstantin Ebauer Institute of Astronomy, Moscow Russia [email protected]

16 Yaoming Ma ITP, CAS, Beijing China [email protected]

17 Harald Schuh Vienna Uni. Tech. Austria [email protected]

18 Jian Sun Wuhan Univ., Wuhan China [email protected]

19 Jeff. Freymueller Uni. of Alaska USA [email protected]

20 Tengyu Zhang SHAO, Shanghai China [email protected]

21 Manabu Hashimoto Kyoto Univ. Japan [email protected]

22 Zhongliang Wu CEA-IGP, Beijing China [email protected]

23 Florian Seitz Tech. Uni. Munich Germany [email protected]

24 Jianjun Zhu Central South Uni. China [email protected]

25 Jens Wickert GFZ, Potsdam Germany [email protected]

26 Ye Li Space Star, Beijing China [email protected]

27 Richard Gross JPL, Caltech USA [email protected]

28 Wenke Sun GUCAS, Beijing China [email protected]

29 Michael Pearlman CFA, Harvard Uni. USA [email protected]

30 Qiming Zeng PKU, Beijing China [email protected]

Sampad Kumar 31 IIT-Mumbai India [email protected] Panda

32 Christopher Kotsakis Aristotle Uni. Th Greece [email protected]

33 Zhengcai Liu Xiangtan Uni., Xiangtan China [email protected]

Wroclaw Univ. of Environ. & 34 Jan Kaplon Poland [email protected] Life Sci.

35 Keke Zhang University of Exeter UK [email protected]

Grad. Uni. Chin. Acd. Sci., 36 Zhipeng Li China [email protected] Beijing

37 Shimon Wdowinski Uni. Miami USA [email protected]

38 Qiang Chen Uni. Stuttgart Germany [email protected]

39 Andy Hooper Delft Uni. Tech. Netherlands [email protected]

40 Najam Naqvi NPU, Xi'an China [email protected]

41 Jose M. Ferrandiz Uni. Alicante Spain [email protected]

42 Heping Sun IGG-CAS, Wuhan China [email protected]

43 Tonie van Dam Uni. Luxembourg Luxembourg [email protected]

44 Sung-Ho Na Korea Astron. Space Sci. Ins. South Korea [email protected]

45 Qi Wang Ins. Seismology, CEA, Wuhan China [email protected]

Noor Suryati Mohd 46 Uni. Tech. Malaysia, Malaysia Malaysia [email protected] Shariff

47 Xiaomin Du CUMT, Beijing China [email protected]

48 Abbas Abedini Uni. of Tehran Iran [email protected]

49 Feng Zhou CUMT, Xuzhou China [email protected]

50 Lawrence Lau Nottingham Uni., Ningbo China [email protected]

51 George Zhizhao Liu Hong Kong Polytechnic Univ. Hong Kong [email protected]

52 Weiyong Yi Tech. Uni. Munich Germany [email protected]

53 Qiang Huang SW Jiaotong Uni. China [email protected]

54 Vladislav Demyanov Irkutsk State Railway Uni. Russia [email protected]

55 Liansheng Deng Wuhan Univ. Wuhan China [email protected]

56 Louisa L. Tsang Nanyang Tech. Uni., Singapore Singapore [email protected]

57 Zhao Li Wuhan Uni. China [email protected]

58 Sung-Ho Na Korea Astron. Space Sci. Ins. South Korea [email protected]

59 Liu Chang Wuhan Uni., Wuhan China [email protected]

60 Alberta Albertella Tech. Uni. Munich Germany [email protected]

61 Pacome Delva Observatoire de Paris, Paris France [email protected]

62 Hong Hu CUMT, Xuzhou China [email protected]

63 Sung-Ho Na Korea Astron. Space Sci. Ins. South Korea [email protected]

64 S. A. Andam-Akorful HHU, Nanjing China [email protected]

65 Shun Zhang Wuhan Uni. China [email protected]

66 Erhu Wei Wuhan Uni., Wuhan China [email protected]

67 Tobias Nilsson Vienna Univ. of Tech. Austria [email protected]

68 Bojing Zhu GUCAS, Beijing China [email protected]

69 Xiaoli Ding Hong Kong Polytechnic Univ. Hong Kong [email protected]

70 Erhu Wei Wuhan Uni., Wuhan China [email protected]

71 Wei Wang Academy of Equipment, Beijing China [email protected]

72 Stephanie Kirschner Tech. Uni. Munich Germany [email protected]

73 Yuei-An Liou National Central Univ. Taiwan [email protected]

74 Guoping Li Chengdu Univ. Info. Tech. China [email protected]

75 Muhammad Faiz Uni. Tech. Malaysia Malaysia [email protected]

Chin. Acad. Surveying & 76 Pengfei Chen China [email protected] Mapping

77 Xiaojun Duan Nat. Univ. Defense Tech. China [email protected]

Opeyemi S. 78 Int. British Ins. Egypt [email protected] Ibraheem

79 Xuechuan Li Wuhan Uni., Wuhan China [email protected]

80 Shuanggen Jin SHAO, CAS, Shanghai China [email protected]

81 Rui M. Fernandes Universidade da Beira Interior Portugal [email protected]

82 Caijun Xu Wuhan Univ. China [email protected]

83 Hui Peng Xiangtan Uni. China [email protected]

84 Deqiang Liu Wuhan Uni. China [email protected]

Ins. Info. Theory & Automation, Czech 85 Milan Talich [email protected] Prague Republic

86 Xuerui Wu Dalian Maritime Univ. China [email protected]

Nat. Space Res. Develop. 87 A. Tahir Yakubu Nigeria [email protected] Agency

88 Hongzhou Yang Wuhan Uni., Wuhan China [email protected]

Joseph Danasabe Nat. Space Res. Develop. 89 Nigeria [email protected] Dodo Agency

90 Xinglong Tan CUMT, Xuzhou China [email protected]

91 Quanwen Zhu Wuhan Uni., Wuhan China [email protected]

92 Shuhui Li CUGB, Beijing China [email protected]

93 Yuannan Wang Wuhan Uni. China [email protected]

94 Qiang Qiu Nanyang Tech. Uni. Singapore [email protected]

95 Zhemin Deng Xiangtan Uni., Xiangtan China [email protected]

96 Linyun Wei Wuhan Uni., Wuhan China [email protected]

97 Qiong Zheng Xiangtan Uni., Xiangtan China [email protected]

98 Xueyan Yang Xiangtan Uni., Xiangtan China [email protected]

99 Yuwei Tan Xiangtan Uni., Xiangtan China [email protected]

100 Sigrid Boehm Vienna Uni. Tech. Austria [email protected]

101 Liming Yuan Xiangtan Uni., Xiangtan China [email protected]

102 Xiaochuan Qu Wuhan Uni. Wuhan China [email protected]

103 Xiangwen Pu Xiangtan Uni., Xiangtan China [email protected]

104 Shien Kwun Leong Uni. Tech. Malaysia, Johor Malaysia [email protected]

105 Xiaosan Man Xiangtan Uni., Xiangtan China [email protected]

106 Yunming Shao IGG, CAS, Wuhan China [email protected]

107 Shuhua Ye SHAO, CAS, Shanghai China [email protected]

108 Jincai Huang CSU, Changsha China [email protected]

109 ChienZheng Yong Uni. Tech. Malaysia, Johor Malaysia [email protected]

110 Jinzhao Liu IGG, CAS, Wuhan China [email protected]

111 Lujia Feng Nanyang Tech. Uni., Singapore Singapore [email protected]

112 Xingwang Zhao Anhui Uni. Sci. Tech. China [email protected]

113 Chao Liu AUST China [email protected]

114 Xinggang Zhang SHAO, Shanghai China [email protected]

115 Lihe Feng SHAO, Shanghai China [email protected]

116 Na Wei Wuhan Uni., Wuhan China [email protected]

117 Zhiqing Dong Wuhan Uni., Wuhan China [email protected]

118 Bin Guo Uni. Sci. Tech. China China [email protected]

119 Shaobo Xia Wuhan Uni., Wuhan China [email protected]

120 Hong Hu CUMT, Xuzhou China [email protected]

121 Wan Anom Wan Aris Uni. Tech. Malaysia Malaysia [email protected]

122 Miao Shi Wuhan Uni., Wuhan China [email protected]

123 Lingyun Wei Wuhan Uni., Wuhan China [email protected]

124 Jinzhao Liu WHIGG, CAS, Wuhan China [email protected]

125 Bing He Wuhan Uni., Wuhan China [email protected]

126 Lihua Wang Wuhan Uni., Wuhan China [email protected]

Nat. Space Res. Develop. 127 J. Omega Onogwu Nigeria [email protected] Agency

128 Vagner G. Ferreira HHU, Nanjing China [email protected]

129 Yingtong Zhang HHU, Nanjing China [email protected]

130 Aojie Di Wuhan Uni., Wuhan China [email protected]

131 Xn Nan HHU, Nanjing China [email protected]

132 Jing Qiao Wuhan Uni., Wuhan China [email protected]

Nat. Space Res. Develop. 133 T. Haruna Sani Nigeria [email protected] Agency

134 Xiaohan Chen Uni. Sci. Tech. China China [email protected]

135 Ishola T. Popoola Int. British Ins. Egypt [email protected]

136 Lihua Li CUGB, Beijing China [email protected]

137 Yansong Xue SHAO, Shanghai China [email protected]

138 Minyuan Cui Wuhan Uni. China [email protected]

139 Oyekunle Oyewole Int. British Ins. Egypt [email protected]

140 Wei Feng IGG & CNES/GRGS China/France [email protected]

141 Hanwei Zhang Henan Poly Uni., Zhengzhou China [email protected]

142 Xing Fang Wuhan Uni., Wuhan China [email protected]

143 Cheng Wang Tongji Uni.,Shanghai China [email protected]

144 Qiang Zhu CUMT, Xuzhou China [email protected]

145 Sam Andam-Akorful HHU, Nanjing China [email protected]

146 Nannan Guo CSU, Changsha China [email protected]

147 Quanwen Zhu Wuhan Uni. China [email protected]

Nat. Space Res. Develop. 148 Y. Samuel Tsebeje Nigeria [email protected] Agency

149 Haiyan Yang Nat. Time Service Center China [email protected]

150 Ya Cao Xiangtan Uni., Xiangtan China [email protected]

151 Zhengyang Pan ITP, CAS China [email protected]

152 Fabio Pulvirenti SHAO, Shanghai China [email protected]

153 Jianguo Yan Wuhan Uni. China [email protected]

154 Baoguo Yu CETC-54 China [email protected]

155 Jia Kong Nat. Time Service Center China [email protected]

156 Ya Ouyang CUG, Wuhan China [email protected]

157 Shilong Liao SHAO, Shanghai China [email protected]

158 Linjing Guo SHAO, Shanghai China [email protected]

159 Qing Li Vienna Uni. Tech. Austria [email protected]

160 Hui Zheng WHIGG, CAS, Wuhan China [email protected]

161 Kalyan G. Shrestha Survey Department Nepal [email protected]

162 Wanli Liu CUMT, Xuzhou China [email protected]

163 Chen Chen Wuhan Uni., Wuhan China [email protected]

164 Mingming Zhu Anhui Uni. Sci. Tech. China [email protected]

165 Wenliang Dong Ins. Surveyig Mapping China [email protected]

166 Cheng Cao Wuhan Uni., Wuhan China [email protected]

167 Zhen Wang XAO, Urumqi China [email protected]

168 Chuandong Zhu IGG, CAS, Wuhan China [email protected]

Shandong Uni. Sci. Tech., 169 Changqing Wang China [email protected] Qingdao

170 Haohan Wei HHU/SHAO China [email protected]

171 Xixuan Bai IGG, CAS, Wuhan China [email protected]

172 Xiaoxing He E. China Ins. Tech China [email protected]

173 Liang Chang SHAO, Shanghai China [email protected]

174 Cui Zhou Central South Uni. China [email protected]

175 Huanhuan Yu National Astro. Observ. CAS China [email protected]

176 Qijie Wang Central South Uni. China [email protected]

177 Ron Zou China Univ. Geosci China [email protected]

178 Xu Tang HHU, Nanjing China [email protected]

179 Xiufeng He HHU, Nanjing China [email protected]

180 Jian Sun Wuhan Univ. China [email protected]

181 Sudong Xiao Uni. Sci. Tech. China China [email protected]

182 Xuyang Zhang Uni. Sci. Tech. China China [email protected]

183 Bofeng Guo Wuhan Uni. China [email protected]

184 Yiping Chen Uni. Sci. Tech. China China [email protected]

185 Cheng-Yung Huang National Central Univ. Taiwan [email protected]

186 Xueqing Xu SHAO, Shanghai China [email protected]

187 Qunhe Zhao SHAO, Shanghai China [email protected]

188 Wenli Dong SHAO, Shanghai China [email protected]

189 Junjie Wang HHU, Nanjing China [email protected]

190 Lin Cai HUST, Wuhan China [email protected]

191 Huishu Li HUST, Wuhan China [email protected]

192 Meng Yang IGG, CAS, Wuhan China [email protected]

193 Yaolin Shi GUCAS, Beijing China [email protected]

194 Fengxian Tong SHAO, CAS China [email protected]

195 Zhicai Li NGCC, Beijing China [email protected]

196 Tian Ding SHAO, CAS China [email protected]

197 Wenyao Zhu SHAO, CAS China [email protected]

198 Luping Zhou Wuhan Univ., China [email protected]

199 Fang Zou Wuhan Univ., China [email protected]

Chin. Acad. Surveying & 200 Yingyan Chen China [email protected] Mapping

201 Wei Liu Wuhan Univ., China [email protected]

Shanghai Astronomical Observatory, Chinese Academy of Sciences 80 Nandan Road, Shanghai 200030, China Website: http://www.shao.ac.cn