
ECLAT D600.1 ECLAT D600.1 Report and “Lessons Learned” from the 1st ECLAT Scientific Workshop October 22 – 24, FMI, Helsinki, Finland Hermann Opgenoorth, IRF The workshop was the first in a sequence of four topically organised ECLAT workshops and it was dedicated to initiate the scientific quality control of the delivered ECLAT data products, in particular the reliability of Cluster footprint mapping using various models during various level of magnetospheric activities, including substorms and localised field aligned currents. The workshop was attended by 30 persons, stemming mainly from the teams of the participating ECLAT partners, CAA and ESA staff, and members of the ECLAT Advisory Board. The program/agenda of the workshop can be found in a separate appendix. All presentations during the workshop have been placed in a dedicated workshop folder on the Internet. In the following we will summarise the discussions under the various agenda items and point out “Lessons Learned” and decisions for “Action Items” for the next ECLAT workshop. Workshop Introductory Talks Steve Milan opened the workshop with a general introduction to the ECLAT project. Rumi Nakamura and Pete Boakes gave a status update on the OEAW region identification product and event finding activities. • The defined and characterised regions are: Lobe, boundary region, outer plasma sheet, inner plasma sheet, the neutral sheet and the plasma sheet boundary layer. • In addition to the identification of such boundaries there will be event lists addressing in particular dynamic features like wavy current sheet, depolarization events and occurrences of thin current sheets and large FACs. • In the following discussion the issue of a difference between OPS (being a region dominated by currents) and PSBL (being dominated by flows) was raised and discussed. It was deferred to closer inspection by working groups in their activities for report back to ECLAT at the next workshop. Steve Milan gave an overview of the SuperDARN data products. • A common grid has now been developed for SuperDARN and MIRACLE data sets (to be used even for the IMAGE dataset). • A first publication (Grocott et al., 2012), and several ongoing papers have already emerged from this activity. Harri Laakso reported on the Cluster Active Archive (CAA) status. • CAA has presently 1400 registered users compared to 240 official Cluster scientists. The Cluster Final Archive (CFA) is now being developed, with a full transfer from CAA to CFA by early to mid 2013. CFA will then become the sole user interface. • ECLAT data can now be found for restricted access at: http://caa.estec.esa.int/caa_stage_search/search.xml • Whenever ECLAT decides so, the data may be released to a wider community. Hermann Opgenoorth · 1 ECLAT D600.1 Olaf Amm reported on the various MIRACLE data analysis tools, which have been further developed and optimised for use by both MIRACLE (densest network) and THEMIS (widest network). • The next step in MIRACLE development is MIRACLE-3D, which could be optimised by more magnetometers in central Scandinavia, particularly Sweden, and a new bi- static radar system (TBC). Minna Palmroth gave a general introduction to the GUMICS code, high-lighting advantages of GUMICS over other models, e.g. including a realistic ionosphere and its coupling to the magnetosphere. The planned Work Packages and consequent submissions to CAA were presented. • GUMICS provides global MHD simulations with realistic assumptions for ionosphere- magnetosphere coupling. • A parallel version of GUMICS is coming soon. Workshop Session 1 (second day of workshop) In contrast to the first day, which consisted of mainly overview presentations, this day was dedicated to more result-based discussions of present and future ECLAT products. Initial ECLAT results were reported, for instance: Steve Milan presented a new method of using spherical harmonic coefficients in quantitative analysis, further interpretation and characterisation of SuperDARN flow patterns. Mark Lester illustrated how SuperDARN data could be used to monitor the variability of the equator-ward edge of the ionospheric convection (the Heppner-Maynard boundary), the main auroral latitude and solar cycle variations in size of convection patterns. Gabor Facsko discussed footprint mapping with GUMICS, and presented some initial results from the GUMICS library runs and first test runs in preparations of the ECLAT full year run project. A long discussion evolved about the exact form and format (e.g., coordinate system, colour code, etc) of the GUMICS ECLAT-CAA products, which the workshop decided to return to in a later session (see for the results of this discussion and consequent decisions below). Nikolai Tsyganenko discussed the different magnetospheric models from St Petersburg State University. • A new model containing a more refined modular structure is under construction and a beta-version is planned for the first quarter of 2013. • In particular the present work concentrates on: a) The IMF control of the boundary shape, and not only solar wind pressure b) The flexibility of the inclusion of an equatorial current sheet c) Dipole tilt effects d) Increase in the validity region of the model e) Inclusion of a partial ring current f) Field aligned currents A question was raised in the discussion whether or not it would be possible to provide a user guide of the various relative benefits of the models, i.e. to advise potential users which Hermann Opgenoorth · 2 ECLAT D600.1 model to use for what purpose. For the next workshop the group from St Petersburg were asked to give a presentation to that end. Another question concerned the possibility to predetermine the open flux in the model, but it appears to be necessary to assimilate such a new model result via multiple model adaptations to data. Alexander Nikolaev showed ECLAT results of footprint mapping for the models TS05 and T96. Results are located at: • http://geo.phys.spbu.ru/~tsyganenko/TS05_data_and_stuff • FTP area: http://geo.phys.spbu.ru Marina Kubyshkina showed examples of mapping the Cluster and GOES via various “Tsyganenko”- codes to the ionosphere • T96, TS05 and AM02 (Adaptive Model) were compared for two spacecraft (Cluster and GOES) • The mapping accuracy was around 1 degree or better for most models, with a higher error for Cluster at higher activity level (3 deg) • However, generally there was no clear correlation between overall mapping accuracy and activity level • The mapping accuracy decreased with radial distance for most cases. • It might not be possible to derive a definite “accuracy map”, as there are too many parameters feeding into the observed uncertainties. Nevertheless, it was proposed by Harri Laakso that one should include the list of identified uncertainties as an ancillary information document to the CAA deliverables. In addition, Steve Milan pointed out that not only latitudinal error, but also MLT shift must be considered in the derived mapping uncertainties. Hermann Opgenoorth presented two example studies (Zivkovic et al., 2012, Cully et al., 2013) of meaningful and exact mapping of field aligned currents in the vicinity of the dayside magnetospheric cusp between CHAMP and Cluster, and ground-based deep tail data- coordination in the case of substorm onset reconnection, respectively. Alexander Nikolaev gave a talk on the testing of an updated substorm current wedge model (SCW2L), where wire type SCW model parameters and R1/R2 current sheets can be added to a model, using dipolarisation amplitudes determined by actual Themis and GOES data. It was found that double current loops systems might become necessary to reproduce the observed magnetic field changes, and suggestions for future Cluster based studies are now required for further validation of the model. Hermann Opgenoorth proposed three potential event studies for field line mapping tests during different levels of substorm activity, all of them located overhead or close to the MIRACLE ground based network, with the footprint of Cluster (and in one case even CHAMP) at a region of central substorm activity. His event examples were: • 20.04.2002 late afternoon sector 1700-2100 UT– Growth phase and westward travelling surge, originating from substorm onset to the east of MIRACLE • 08.09.2002 midnight sector 2000-2200 UT – Overhead substorm onset • 04.09.2005 midnight sector 2000-2200 UT– 2nd Substorm intensification at higher latitudes over Svalbard Workshop session 2 Hermann Opgenoorth · 3 ECLAT D600.1 Gabor Facsko gave a more detailed review concerning the development and distribution of the ECLAT GUMICS static run library. It was found a.o. that the GUMICS runs were not stable for some chosen parameter-values of exactly 0, and that therefore some minute deviations had to be introduced to stabilise the calculations and avoiding zero-divisions. The results of the library runs can now be found under • http://hwa.fmi.fi • eclat.fmi.fi/dev/login2.php (requires username and passwd) Evgenij Gordeev showed a test of the GUMICS-4 against empirical data, pointing out several critical facts: • Different dynamics of the real magnetosphere during the same SW conditions, as the real magnetosphere often has a memory of previous solar wind conditions, while models start from the present value as chosen by the user. • Lobe magnetic field: Gumics < 20% than empirical (Fairfield Jones) • Magnetotail radius: 10% less than Shue model • Plasma sheet pressure: ~OK (agrees in average but with large scatter) • Plasma sheet geometry: typically very good agreement • Cross polar cap potential: GUMICS typically lower value and much wider distribution • Less magnetic flux in GUMICS magnetotail (especially for southward IMF) • In summary: Generally GUMICS-4 satisfactorily simulates the magnetospheric system (in a statistical sense) In the following discussion proposals were made to include the coefficient method of Grocott et al., for a more quantitative assessment of the GUMICS results concerning convection. A general finding is that GUMICS appears to perform better in “real data” simulations than for these “synthetic” library runs, where fixed values were chosen.
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