GEM Magnetopause Challenge
Back in 2008, we started looking at global magnetosphere models in comparison with the Shue et al (1998) magnetopause model. At that time, two-hour intervals of successively stronger southward solar wind Bz were used to run the models SWMF, OpenGGCM, GUMICS and LFM.
The models were found to show magnetopause standoff distances that could vary by over one RE. It was concluded that the presence of a ring current increases the predicted magnetopause standoff. However, the inclusion of a ring current increases the standoff only by about 1/2 RE and thus does not account for the total difference (between the SWMF and OpenGGCM models). Other factors are inner (near-Earth) boundary conditions such as density, temperature and the position of the boundary itself, that vary between the models. A sensitivity study was started but yielded inconclusive results.
A summary of some of those efforts are included in L. Rastaetter's presentation at the 2015 GEM Summer Workshop.
More recently, the focus shifted from modeled conditions to real events when Magnetopause crossings were included as one observable parameter in the GEM magnetosphere modeling challenge.
Events included a day during the Halloween storm (2003/10/29 06:00-2003/10/30 06:00 UT) and 36 hours during the AGU storm (2006/12/14 12:00 -- 2016/12/16 00:00 UT), featuring multiple magnetopause crossings by GOES and LANL geosynchronous satellites.
Recent advances in data preparation and visualization of data-model comparison time series allow for event-based analysis of magnetopause crossings and the calculation of skill scores similar to the dBH/dt study that was completed in 2013 (see Rastaetter's presentation at the 2015 GEM workshop).
On this page we will post events that feature multi-spacecraft magnetopause crossings that we may include in addition to the geosynchronous satellites that encountered the magnetopause during the above-mentioned challenge events (see presentation by Collado-Vega and Sibeck and by Rastaetter (additional slides), also presented during the 2015 GEM meeting).
GEM Workshop Sessions
2015 Summer Workshop, Metrics and Validation, session #1: Wed, June 17 2015, 10:30-12:15
i. Magnetopause crossing challenge
- Yari Collado-Vega (given by L. Rastaetter): Magnetopause standoff position and response time changes due to solar wind conditions: Models and Observations [PDF]
- Mike Wiltberger: Magnetopause dynamics during the March 17th, 2013 event [PDF]
ii. Additional M&V contributions
iii. M&V Wrap up: Recent highlights and future plans for M&V at GEM
- Howard Singer: discussion [PDF]