DOCSLIB.ORG

Towards an Integrated Storm Surge and Wave Forecasting System for Taiwan Coast

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Towards an Integrated Storm Surge and Wave Forecasting System for Taiwan Coast Volume 26 Issue 1 Article 12 TOWARDS AN INTEGRATED STORM SURGE AND WAVE FORECASTING SYSTEM FOR TAIWAN COAST Yeayi Peter Sheng University of Florida, Gainesville, Florida, U.S.A, [email protected] Vladimir Alexander Paramygin University of Florida, Gainesville, Florida, U.S.A. Chuen-Teyr Terng Central Weather Bureau, Taipei, Taiwan, R.O.C. Chi-Hao Chu Central Weather Bureau, Taipei, Taiwan, R.O.C. Follow this and additional works at: https://jmstt.ntou.edu.tw/journal Part of the Marine Biology Commons Recommended Citation Sheng, Yeayi Peter; Paramygin, Vladimir Alexander; Terng, Chuen-Teyr; and Chu, Chi-Hao (2018) "TOWARDS AN INTEGRATED STORM SURGE AND WAVE FORECASTING SYSTEM FOR TAIWAN COAST," Journal of Marine Science and Technology: Vol. 26 : Iss. 1 , Article 12. DOI: 10.6119/JMST.2018.02_(1).0011 Available at: https://jmstt.ntou.edu.tw/journal/vol26/iss1/12 This Research Article is brought to you for free and open access by Journal of Marine Science and Technology. It has been accepted for inclusion in Journal of Marine Science and Technology by an authorized editor of Journal of Marine Science and Technology. TOWARDS AN INTEGRATED STORM SURGE AND WAVE FORECASTING SYSTEM FOR TAIWAN COAST Acknowledgements Central Weather Bureau provided the field data used for model erificationv in this paper. We appreciate the comments of two anonymous reviewers. This research article is available in Journal of Marine Science and Technology: https://jmstt.ntou.edu.tw/journal/ vol26/iss1/12 Journal of Marine Science and Technology, Vol. 26, No. 1, pp. 117-127 (2018) 117 DOI: 10.6119/JMST.2018.02_(1).0011 TOWARDS AN INTEGRATED STORM SURGE AND WAVE FORECASTING SYSTEM FOR TAIWAN COAST Yeayi Peter Sheng1, Vladimir Alexander Paramygin1, Chuen-Teyr Terng2, and Chi-Hao Chu2 Key words: storm surge, wave, numerical simulation, forecasting, I. INTRODUCTION Taiwan. More than 75% of the world’s population live within 100 miles from the coastline. Coastal communities and ecosystems around ABSTRACT the world are subjected to increasing hazard from storm surge This paper describes the application of a coupled surge-wave and coastal inundation due to tropical cyclones as well as cli- model for simulating storm surge and wave along Taiwan coast. mate change and sea level rise. In Taiwan typhoons are an an- The simulations were conducted with an integrated surge-wave nual threat. Not only bringing torrential rain, but often cause modeling system using a large coastal model domain wrapped storm surge and coastal inundation that impacts areas near the around the island of Taiwan, with a grid resolution of 50-400 m. coast and amplifies the flooding from rainfall. The impact of tro- Simulations were made with tide only, with wind and tide, and pical cyclones on the coastal regions in Taiwan depend on the with tide and wind and wave. tropical cyclone characteristics and coastal region characteristics. The first part of the paper describes the hindcasting of his- For example, along the southwest coast of Taiwan with low ele- torical typhoons. Hindcasting of Soudelor in 2015 revealed the vation and gentler bathymetric slope, major flooding often occurs significant effect of waves on storm surge when wave exceeded due to storm surge during tropical cyclones. Typhoon Fanapi 11 m. Both the water level and wave were well simulated by the caused major flooding along the southwest coast of Taiwan in surge-wave model. The second part of the paper describes the September 2010. Along the rocky northeast coast of Taiwan forecasting of typhoons in 2016 With a focus on typhoon Napartak where the bathymetric slope is steep, waves often break very and Megi to examine the reliability, accuracy, and efficiency of close to the coastline and contribute significantly to the storm the protopype forecasting system for Taiwan coast. surge. During July 2013, Typhoon Soulik cuased significant The system uptime is estimated at 78% during the three months storm surges and waves along the northeast coast of Taiwan. of operations. While the tide prediction has about 3-10% error This is also true for Typhoon Soudelor (2015). Although storm (relative root-mean-square-error), the water level prediction error surge is typically not as high as waves along the coast of Taiwan, increases from 5.8-13.5% for now cast to 9.8-17.4% for 6-hour rising sea level and increasingly more intense typhoons are mostly forecast, 11.4-18.2% for 12-hour forecast, and 20.3-31.4% for likely to result in higher storm surge in the 21st century which, 24-hour forecast. The forecast error increases quickly for 24-hour coupled with increasing precipitation and subsidence in south- forecast, due to the quick decline of typhoon track/intensity fore- west Taiwan, could significantly increase the risk of coastal cast accuracy beyond 24 hours. The forecasting system is run flooding in Taiwan. Therefore, a robust storm surge and wave using an Intel-based PC with the Intel® Core™ i7-3770 CPU @ forecasting system for Taiwan is urgently needed. 3.40 Ghz (4 cores/8 threads) with 32GB RAM. Wall time varies Numerous storm surge studies have been conducted around between 0.8 and 1.8 hours. Taiwan using a number of different storm surge models, e.g., CWB-1 model (Yu et al., 1994), CWB-2 model (Wu, 2014), TORI (Taiwan Ocean Research Institute) model (Liau and Chen, 2015), and HMTC (Harbor and Marine Technology Center) mo- del (Lee et al., 2015). According to a review by Sheng (2015), these models did not include wave effects. In addition, the grid Paper submitted 02/13/17; revised 07/24/17; accepted 09/07/17. Author for resolution of the CWB-1 and CWB-2 are relatively coarse correspondence: Y. Peter Sheng (e-mail: [email protected]). 1 University of Florida, Gainesville, Florida, U.S.A. (> 200 m). These factors contributed to the relatively large errors 2 Central Weather Bureau, Taipei, Taiwan, R.O.C. in the storm surge simulation during past typhoons including 118 Journal of Marine Science and Technology, Vol. 26, No. 1 (2018) Legend Soudelor track Fig. 2. Typhoon Nepartak (2016) track. Fig. 1. Computational domain and track of Typhoon Soudelor in 2015. Fanapi in 2010 and Soulik in 2013. Sheng et al. (2016) has shown that coupled wave-surge model can significantly improve the water level predictions where waves play a major role. This paper uses an integrated storm surge modeling system (Sheng et al., 2010a, 2010b) to simulate storm surge and coastal inundation during typhoon Soudelor (2015). The simulations use a coastal model domain (Fig. 1) wrapped around the island of Taiwan with a grid resolution of 50-300 m coupled to a larger rec- tangular domain to provide boundary conditions for the simu- lation capturing surge and waves away from the coast. The same basic modeling system, with appropriate supporting modules, Fig. 3. Typhoon Megi (2016) track. is used to forecast the storm surge and wave during 2016 and results during Nepartak and Megi are presented in this paper. The reliability, accuracy, and efficiency of the prototype fore- 2. Typhoon Nepartak (2016) casting system is assessed. in eastern Taiwan experienced the heaviest rains from the ty- phoon, with accumulations peaking at 1,334 mm. Rainfall in the Wulai District reached 722 mm in 24 hours. Twelve-hour II.TYPHOONS IN 2015 AND 2016 accumulations amounted to a record 632 mm. We describe Typhoon Soudelor in 2015 and Typhoon Nepartak Typhoon Nepartak (Fig. 2) is the second most intense tro- and Megi in 2016 below. pical cyclone in 2016 in terms of atmospheric pressure. Nepartak severely impacted Taiwan and East China, with 86 confirmed 1. Typhoon Soudelor (2015) fatalities. It caused 3 deaths and NT$677 million (US$21.1 Typhoon Soudelor (Wikipedia, 2017) was the most intense million) of damage in Taiwan. The first named storm and ty- tropical cyclone to develop in the Pacific Ocean and the third phoon of the annual typhoon season, Nepartak developed into most intense cyclone worldwide in 2015, and the strongest ty- a tropical storm south of Guam on July. Steadily tracking north- phoon since Typhoon Vongfong. Soudelor had severe impacts westward and becoming a typhoon on the next day, Nepartak in the Northern Mariana Islands, Taiwan, and eastern China, reached peak intensity with a pinhole eye on July 6. Nepartak resulting in at least 38 confirmed fatalities. Lesser effects were started to decay on July 7 and then crossed Taiwan later, before felt in Japan, South Korea and the Philippines. Soudelor formed emerging into the Taiwan Strait and weakening into a severe tro- as a tropical depression on July 29 near Pohnpei and was the pical storm on July 8. It eventually made landfall over Fujian, thirteenth named storm of the 2015 typhoon season. It was slowly China on July 9 and dissipated over land one day later. strengthening and several days later started intensifying on August 2. 3. Typhoon Megi (2016) The center of the storm made landfall in eastern Taiwan at Typhoon Megi (Fig. 3), known in the Philippines as Typhoon 04:40 a.m. local time on August 8. By about 9 a.m., Soudelor had Helen, was a large and powerful tropical cyclone which affected maximum sustained winds of 173 km/h, according to Taiwanʼs Taiwan and China in late September 2016. It is the seventeenth Central Weather Bureau (CWB-MMC). Winds caused Taipei named storm and the seventh typhoon of the annual typhoon 101ʼs tuned mass damper to sway a record 100 cm. Yilan County season. Y. P. Sheng et al.: Storm Surge and Wave Forecasting for Taiwan Coast 119 Atmospheric Basing-Scale Coastal Model Products Models Models Basin-Scale Surge Models (CH3D, Coastal Surge HYCOM, NCOM, Model (CH3D) ROMS) Inundation Map GFDL, HRD, NAM, WRF, WNA, Synthetic models Surge, Basin-Scale Waves, Coastal Wave Wave Model Currents Model (SWAN) (WAVEWATCH-III) Fig.
Load more

Recommended publications
  • Characteristics of Satellite-Based Ocean Turbulent Heat Flux Around the Korean Peninsula and Relationship with Changes in Typhoon Intensity
    remote sensing Article Characteristics of Satellite-Based Ocean Turbulent Heat Flux around the Korean Peninsula and Relationship with Changes in Typhoon Intensity Jaemin Kim and Yun Gon Lee * Atmospheric Sciences, Department of Astronomy, Space Science, and Geology, Chungnam National University, Daejeon 34134, Korea; [email protected] * Correspondence: [email protected]; Tel.: +82-042-821-7107 Abstract: Ocean-atmosphere energy exchange is an important factor in the maintenance of oceanic and atmospheric circulation and the regulation of meteorological and climate systems. Oceanic sensible and latent heat fluxes around the Korean Peninsula were determined using satellite-based air-sea variables (wind speed, sea surface temperature, and atmospheric specific humidity and temperature) and the coupled ocean-atmosphere response experiment (COARE) 3.5 bulk algorithm for six years between 2014 and 2019. Seasonal characteristics of the marine heat flux and its short- term fluctuations during summer typhoons were also investigated. Air-sea variables were produced through empirical relationships and verified with observational data from marine buoys around the Korean Peninsula. Satellite-derived wind speed, sea surface temperature, atmospheric specific humidity, and air temperature were strongly correlated with buoy data, with R2 values of 0.80, 0.97, 0.90, and 0.91, respectively. Satellite-based sensible and latent heat fluxes around the peninsula were also validated against fluxes calculated from marine buoy data, and displayed low values in summer and higher values in autumn and winter as the difference between air-sea temperature and specific humidity increased. Through analyses of spatio-temporal fluctuations in the oceanic turbulent heat Citation: Kim, J.; Lee, Y.G.
    [Show full text]
  • An Efficient Method for Simulating Typhoon Waves Based on A
    Journal of Marine Science and Engineering Article An Efficient Method for Simulating Typhoon Waves Based on a Modified Holland Vortex Model Lvqing Wang 1,2,3, Zhaozi Zhang 1,*, Bingchen Liang 1,2,*, Dongyoung Lee 4 and Shaoyang Luo 3 1 Shandong Province Key Laboratory of Ocean Engineering, Ocean University of China, 238 Songling Road, Qingdao 266100, China; [email protected] 2 College of Engineering, Ocean University of China, 238 Songling Road, Qingdao 266100, China 3 NAVAL Research Academy, Beijing 100070, China; [email protected] 4 Korea Institute of Ocean, Science and Technology, Busan 600-011, Korea; [email protected] * Correspondence: [email protected] (Z.Z.); [email protected] (B.L.) Received: 20 January 2020; Accepted: 23 February 2020; Published: 6 March 2020 Abstract: A combination of the WAVEWATCH III (WW3) model and a modified Holland vortex model is developed and studied in the present work. The Holland 2010 model is modified with two improvements: the first is a new scaling parameter, bs, that is formulated with information about the maximum wind speed (vms) and the typhoon’s forward movement velocity (vt); the second is the introduction of an asymmetric typhoon structure. In order to convert the wind speed, as reconstructed by the modified Holland model, from 1-min averaged wind inputs into 10-min averaged wind inputs to force the WW3 model, a gust factor (gf) is fitted in accordance with practical test cases. Validation against wave buoy data proves that the combination of the two models through the gust factor is robust for the estimation of typhoon waves.
    [Show full text]
  • Forecasting of Storm Surge and Wave Along Taiwan Coast Y
    Forecasting of Storm Surge and Wave along Taiwan Coast Y. Peter Sheng1, *, Vladimir A. Paramygin2, Chuen-Teyr Terng 3, and Chi-Hao Chu 3 1Advanced Aqua Dynamics, Inc., Gainesville, Florida, U.S.A. 2 University of Florida, Gainesville, Florida, U.S.A. 3 Central Weather Bureau, Taipei, Taiwan, R.O.C. *Corresponding Author: [email protected] Abstract This paper describes the application of a coupled surge-wave modeling system CH3D-SWAN for simulating storm surge and wave along Taiwan coast. The modeling system has been used for simulating storm surge and wave in the U.S., Arabian Gulf, and Taiwan. This paper presents the hindcasting of Typhoon Soudelor in 2015 and the forecasting of the typhoon season in 2016 with Typhoon Meiji as an example. Performance of the forecasting system is assessed and future forecasting effort is discussed. Key words: Storm Surge, Wave, Numerical Simulation, Forecasting, Taiwan 1. Introduction typhoons of Taiwan. In the following section, we first give a brief description of the CH3D-SWAN modeling In Taiwan, typhoons are an annual threat. Typhoons not only bring torrential rain, but often cause storm surge, wave, and coastal inundation that system with all the associated modules of the impact areas near the coast and amplifies the flooding forecasting system and model domains. Model from rainfall. The impact of tropical cyclones on the hindcasting of storm surge and wave during Typhoon coastal regions in Taiwan depend on the Soudelor in 2015 is then described, followed by a characteristics of tropical cyclones and coastal regions. description of the forecasting performance of the 2016 For example, along the southwest coast of Taiwan typhoon season using Typhoon Meji as an example.
    [Show full text]
  • Improved Global Tropical Cyclone Forecasts from NOAA: Lessons Learned and Path Forward
    Improved global tropical cyclone forecasts from NOAA: Lessons learned and path forward Dr. Vijay Tallapragada Chief, Global Climate and Weather Modeling Branch & HFIP Development Manager Typhoon Seminar, JMA, Tokyo, Japan. NOAA National Weather Service/NCEP/EMC, USA January 6, 2016 Typhoon Seminar JMA, January 6, 2016 1/90 Rapid Progress in Hurricane Forecast Improvements Key to Success: Community Engagement & Accelerated Research to Operations Effective and accelerated path for transitioning advanced research into operations Typhoon Seminar JMA, January 6, 2016 2/90 Significant improvements in Atlantic Track & Intensity Forecasts HWRF in 2012 HWRF in 2012 HWRF in 2015 HWRF HWRF in 2015 in 2014 Improvements of the order of 10-15% each year since 2012 What it takes to improve the models and reduce forecast errors??? • Resolution •• ResolutionPhysics •• DataResolution Assimilation Targeted research and development in all areas of hurricane modeling Typhoon Seminar JMA, January 6, 2016 3/90 Lives Saved Only 36 casualties compared to >10000 deaths due to a similar storm in 1999 Advanced modelling and forecast products given to India Meteorological Department in real-time through the life of Tropical Cyclone Phailin Typhoon Seminar JMA, January 6, 2016 4/90 2014 DOC Gold Medal - HWRF Team A reflection on Collaborative Efforts between NWS and OAR and international collaborations for accomplishing rapid advancements in hurricane forecast improvements NWS: Vijay Tallapragada; Qingfu Liu; William Lapenta; Richard Pasch; James Franklin; Simon Tao-Long
    [Show full text]
  • Variations in Typhoon Landfalls Over China Emily A
    Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2004 Variations in Typhoon Landfalls over China Emily A. Fogarty Follow this and additional works at the FSU Digital Library. For more information, please contact [email protected] THE FLORIDA STATE UNIVERSITY COLLEGE OF SOCIAL SCIENCES VARIATIONS IN TYPHOON LANDFALLS OVER CHINA By EMILY A. FOGARTY A Thesis submitted to the Department of Geography in partial fulfillment of the requirements for the degree of Master of Science Degree Awarded: Fall Semester, 2004 The members of the Committee approve Thesis of Emily A. Fogarty defended on October 20, 2004. James B. Elsner Professor Directing Thesis Thomas Jagger Committee Member J. Anthony Stallins Committee Member The Office of Graduate Studies has verified and approved the above named committee members. ii ACKNOWLEDGEMENTS Special thanks to my advisor James Elsner, without his guidance none of this would be possible. Thank you to my other advisors Tom Jagger and Tony Stallins for their wonderful advice and help. Finally thank you to Kam-biu Liu from Louisiana State University for providing the historical data used in this study. iii TABLE OF CONTENTS List of Tables ................................................... .... v List of Figures ................................................... ... vi Abstract ................................................... ......... vii 1. INTRODUCTION ............................................... 1 2. DATA ................................................... ....... 4 2.1 Historical Typhoons over Guangdong and Fujian Province . 5 2.2 Modern Typhoon Records . 7 2.3 ENSO and the Pacific Decadal Oscillation . 8 2.4 NCEP/NCAR Reanalysis Data . 9 3. ANTICORRELATION BETWEEN GUANGDONG AND FUJIAN TYPHOON ACTIVITY .......................................... 12 4. SPATIAL CO-VARIABILITY IN CHINA LANDFALLS ............. 15 4.1 Factor Analysis Model . 16 4.2 Statistical Significance of the Factor Analysis Model .
    [Show full text]
  • Appendix 8: Damages Caused by Natural Disasters
    Building Disaster and Climate Resilient Cities in ASEAN Draft Finnal Report APPENDIX 8: DAMAGES CAUSED BY NATURAL DISASTERS A8.1 Flood & Typhoon Table A8.1.1 Record of Flood & Typhoon (Cambodia) Place Date Damage Cambodia Flood Aug 1999 The flash floods, triggered by torrential rains during the first week of August, caused significant damage in the provinces of Sihanoukville, Koh Kong and Kam Pot. As of 10 August, four people were killed, some 8,000 people were left homeless, and 200 meters of railroads were washed away. More than 12,000 hectares of rice paddies were flooded in Kam Pot province alone. Floods Nov 1999 Continued torrential rains during October and early November caused flash floods and affected five southern provinces: Takeo, Kandal, Kampong Speu, Phnom Penh Municipality and Pursat. The report indicates that the floods affected 21,334 families and around 9,900 ha of rice field. IFRC's situation report dated 9 November stated that 3,561 houses are damaged/destroyed. So far, there has been no report of casualties. Flood Aug 2000 The second floods has caused serious damages on provinces in the North, the East and the South, especially in Takeo Province. Three provinces along Mekong River (Stung Treng, Kratie and Kompong Cham) and Municipality of Phnom Penh have declared the state of emergency. 121,000 families have been affected, more than 170 people were killed, and some $10 million in rice crops has been destroyed. Immediate needs include food, shelter, and the repair or replacement of homes, household items, and sanitation facilities as water levels in the Delta continue to fall.
    [Show full text]
  • Simulating Storm Surge and Inundation Along the Taiwan Coast During Typhoons Fanapi in 2010 and Soulik in 2013
    Terr. Atmos. Ocean. Sci., Vol. 27, No. 6, 965-979, December 2016 doi: 10.3319/TAO.2016.06.13.01(Oc) Simulating Storm Surge and Inundation Along the Taiwan Coast During Typhoons Fanapi in 2010 and Soulik in 2013 Y. Peter Sheng1, *, Vladimir A. Paramygin1, Chuen-Teyr Terng 2, and Chi-Hao Chu 2 1 University of Florida, Gainesville, Florida, U.S.A. 2 Central Weather Bureau, Taipei City, Taiwan, R.O.C. Received 10 January 2016, revised 9 June 2016, accepted 13 June 2016 ABSTRACT Taiwan is subjected to significant storm surges, waves, and coastal inundation during frequent tropical cyclones. Along the west coast, with gentler bathymetric slopes, storm surges often cause significant coastal inundation. Along the east coast with steep bathymetric slopes, waves can contribute significantly to the storm surge in the form of wave setup. To examine the importance of waves in storm surges and quantify the significance of coastal inundation, this paper presents numerical simulations of storm surge and coastal inundation during two major typhoons, Fanapi in 2010 and Soulik in 2013, which impacted the southwest and northeast coasts of Taiwan, respectively. The simulations were conducted with an integrated surge-wave modeling system using a large coastal model domain wrapped around the island of Taiwan, with a grid resolution of 50 - 300 m. During Fanapi, the simulated storm surge and coastal inundation near Kaohsiung are not as accurate as those obtained using a smaller coastal domain with finer resolution (40 - 150 m). During Soulik, the model simulations show that wave setup contributed significantly (up to 20%) to the peak storm surge along the northeast coast of Taiwan.
    [Show full text]
  • An Introduction to Humanitarian Assistance and Disaster Relief (HADR) and Search and Rescue (SAR) Organizations in Taiwan
    CENTER FOR EXCELLENCE IN DISASTER MANAGEMENT & HUMANITARIAN ASSISTANCE An Introduction to Humanitarian Assistance and Disaster Relief (HADR) and Search and Rescue (SAR) Organizations in Taiwan WWW.CFE-DMHA.ORG Contents Introduction ...........................................................................................................................2 Humanitarian Assistance and Disaster Relief (HADR) Organizations ..................................3 Search and Rescue (SAR) Organizations ..........................................................................18 Appendix A: Taiwan Foreign Disaster Relief Assistance ....................................................29 Appendix B: DOD/USINDOPACOM Disaster Relief in Taiwan ...........................................31 Appendix C: Taiwan Central Government Disaster Management Structure .......................34 An Introduction to Humanitarian Assistance and Disaster Relief (HADR) and Search and Rescue (SAR) Organizations in Taiwan 1 Introduction This information paper serves as an introduction to the major Humanitarian Assistance and Disaster Relief (HADR) and Search and Rescue (SAR) organizations in Taiwan and international organizations working with Taiwanese government organizations or non-governmental organizations (NGOs) in HADR. The paper is divided into two parts: The first section focuses on major International Non-Governmental Organizations (INGOs), and local NGO partners, as well as international Civil Society Organizations (CSOs) working in HADR in Taiwan or having provided
    [Show full text]
  • Using Adjacent Buoy Information to Predict Wave Heights of Typhoons Offshore of Northeastern Taiwan
    water Article Using Adjacent Buoy Information to Predict Wave Heights of Typhoons Offshore of Northeastern Taiwan Chih-Chiang Wei * and Chia-Jung Hsieh Department of Marine Environmental Informatics & Center of Excellence for Ocean Engineering, National Taiwan Ocean University, Keelung 20224, Taiwan; [email protected] * Correspondence: [email protected] Received: 2 November 2018; Accepted: 6 December 2018; Published: 7 December 2018 Abstract: In the northeastern sea area of Taiwan, typhoon-induced long waves often cause rogue waves that endanger human lives. Therefore, having the ability to predict wave height during the typhoon period is critical. The Central Weather Bureau maintains the Longdong and Guishandao buoys in the northeastern sea area of Taiwan to conduct long-term monitoring and collect oceanographic data. However, records have often become lost and the buoys have suffered other malfunctions, causing a lack of complete information concerning wind-generated waves. The goal of the present study was to determine the feasibility of using information collected from the adjacent buoy to predict waves. In addition, the effects of various factors such as the path of a typhoon on the prediction accuracy of data from both buoys are discussed herein. This study established a prediction model, and two scenarios were used to assess the performance: Scenario 1 included information from the adjacent buoy and Scenario 2 did not. An artificial neural network was used to establish the wave height prediction model. The research results demonstrated that (1) Scenario 1 achieved superior performance with respect to absolute errors, relative errors, and efficiency coefficient (CE) compared with Scenario 2; (2) the CE of Longdong (0.802) was higher than that of Guishandao (0.565); and (3) various types of typhoon paths were observed by examining each typhoon.
    [Show full text]
  • Recent Advances in Research and Forecasting of Tropical Cyclone Rainfall
    106 TROPICAL CYCLONE RESEARCH AND REVIEW VOLUME 7, NO. 2 RECENT ADVANCES IN RESEARCH AND FORECASTING OF TROPICAL CYCLONE RAINfaLL 1 2 3 4 5 KEVIN CHEUNG , ZIFENG YU , RUSSELL L. ELSBErry , MICHAEL BELL , HAIYAN JIANG , 6 7 8 9 TSZ CHEUNG LEE , KUO-CHEN LU , YOSHINORI OIKAWA , LIANGBO QI , 10 11 ROBErt F. ROGERS , KAZUHISA TSUBOKI 1Macquarie University, Sydney, Australia 2Shanghai Typhoon Institute, Shanghai, China 3University of Colorado Colorado Springs, Colorado Springs, USA 4Colorado State University, Fort Collins, USA 5Florida International University, Miami, USA 6Hong Kong Observatory, Hong Kong, China 7Pacific Science Association 8RSMC Tokyo/Japan Meteorological Agency, Tokyo, Japan 9Shanghai Meteorological Service, Shanghai, China 10NOAA/AOML/Hurricane Research Division, Miami, USA 11Nagoya University, Nagoya, Japan ABSTRACT In preparation for the Fourth International Workshop on Tropical Cyclone Landfall Processes (IWTCLP-IV), a summary of recent research studies and the forecasting challenges of tropical cyclone (TC) rainfall has been prepared. The extreme rainfall accumulations in Hurricane Harvey (2017) near Houston, Texas and Typhoon Damrey (2017) in southern Vietnam are examples of the TC rainfall forecasting challenges. Some progress is being made in understanding the internal rainfall dynamics via case studies. Environmental effects such as vertical wind shear and terrain-induced rainfall have been studied, as well as the rainfall relationships with TC intensity and structure. Numerical model predictions of TC-related rainfall have been improved via data as- similation, microphysics representation, improved resolution, and ensemble quantitative precipitation forecast techniques. Some attempts have been made to improve the verification techniques as well. A basic forecast challenge for TC-related rainfall is monitoring the existing rainfall distribution via satellite or coastal radars, or from over-land rain gauges.
    [Show full text]
  • Long-Lived Concentric Eyewalls in Typhoon Soulik (2013)
    SEPTEMBER 2014 Y A N G E T A L . 3365 Long-Lived Concentric Eyewalls in Typhoon Soulik (2013) YI-TING YANG Office of Disaster Management, New Taipei City, Taiwan ERIC A. HENDRICKS Marine Meteorology Division, Naval Research Laboratory, Monterey, California HUNG-CHI KUO Department of Atmospheric Sciences, National Taiwan University, Taipei, Taiwan MELINDA S. PENG Marine Meteorology Division, Naval Research Laboratory, Monterey, California (Manuscript received 24 March 2014, in final form 25 May 2014) ABSTRACT The authors report on western North Pacific Typhoon Soulik (2013), which had two anomalously long-lived concentric eyewall (CE) episodes, as identified from microwave satellite data, radar data, and total pre- cipitable water data. The first period was 25 h long and occurred while Soulik was at category 4 intensity. The second period was 34 h long and occurred when Soulik was at category 2 intensity. A large moat and outer eyewall width were present in both CE periods, and there was a significant contraction of the inner eyewall radius from the first period to the second period. The typhoon intensity decrease was partially due to en- countering unfavorable environmental conditions of low ocean heat content and dry air, even though inner eyewall contraction would generally support intensification. The T–Vmax diagram (where T is the brightness temperature and Vmax is the best track–estimated intensity) is used to analyze the time sequence of the intensity and convective activity. The convective activity (and thus the integrated kinetic energy) increased during the CE periods despite the weakening of intensity. 1. Introduction and documented the ERC occurrence and subsequent weakening using aircraft observations.
    [Show full text]
  • Annual Report on the Climate System 2016
    Annual Report on the Climate System 2016 March 2017 Japan Meteorological Agency Preface The Japan Meteorological Agency is pleased to publish the Annual Report on the Climate System 2016. The report summarizes 2016 climatic characteristics and climate system conditions worldwide, with coverage of specific events including the effects of the summer 2014 – spring 2016 El Niño event and notable aspects of Japan’s climate in summer 2016. I am confident that the report will contribute to the understanding of recent climatic conditions and enhance awareness of various aspects of the climate system, including the causes of extreme climate events. Teruko Manabe Director, Climate Prediction Division Global Environment and Marine Department Japan Meteorological Agency Contents Preface 1. Explanatory notes ··························································································· 1 1.1 Outline of the Annual Report on the Climate System ······································· 1 1.2 Climate in Japan ···················································································· 1 1.3 Climate around the world ························································ ·············· 2 1.4 Atmospheric circulation ············· ···························································· 3 1.5 Oceanographic conditions ··········· ··············································· ·········· 5 1.6 Snow cover and sea ice ······································································· 5 2. Annual summaries of the 2016 climate system
    [Show full text]