GEM NGRSC 2009
1. GEM Space Radiation Climatology (FG9)/NGRSC Joint Workshop 2009
This year the GEM Space Radiation Climatology Focus Group will be hosting the Next Generation Radiation Specifications Consortium (NGRSC) in a 2-day joint meeting at the GEM Summer Workshop, 2009.
1.1. What is GEM Space Radiation Climatology?
1.2. What is NGRSC?
NGRSC (Next Generation Radiation Specifications Consortium) is an informal consortium of scientists, supported by separate research grants from various agencies. For example, some participants are funded by their GEM grants, some by NASA LWS TR&T grants, etc.
The NGRSC focus is development of radiation specification models to replace the out-of-date AE-8 and AP-8 models. The new models will improve upon AE-8 and AP-8 by being more accurate and more capable. New capabilities will include worst case environments and extended particle energy coverage. These new capabilities will help address spacecraft charging and surface dose effects which are not addressed by the current generation of specification models, except in select orbits. The workshop consisted of about 25 participants from Aerospace, Air Force Research Lab, Los Alamos National Lab, NOAA, ONERA (The French Aerospace Lab), Naval Research Lab, UCLA, and the University of Texas. Workshop presentations typically include updates on satellite particle radiation data inter-calibration, statistical models and methods, and data assimilation. Support for this effort comes from a wide array of sources, including the NRO's Proton Spectrometer Belt Research (PSBR) program and NASA's Living With a Star (LWS) program, NSF's Geospace Environment Modelling (GEM) program, and The Aerospace Corporation's IR&D program.
2. Session Description
2.1. Wednesday, June 24th (NGRSC emphasized)
Space Radiation Climatology joint meeting with Next Generation Radiation Specifications Consortium (NGRSC). This schedule will be, if anything, more workshoppy even than GEM. We will try to allocate about 20-30 minutes of open discussion time per presentation.
2.1.1. NGRSC Project Updates (I)
AM: 10:30-12:15 - Kearns
2.1.2. NGRSC Project Updates (II)
PM1: 1:30-3:00 - Kearns
2.1.3. Tools Updates et Cetera
PM2: 3:30-5:00 - Kearns
- VERB code Update (Subbotin) Executable w/ customizable input file is on-line, and it's fast
- RBE code (Fok) Running at CCMC but you can also download and compile for yourself here: http://mcf.gsfc.nasa.gov/exports/Bonechi/. If there is interest, Fok will put effort into making the code more accessible. The CCMC presently only allows this model to be run at the same time as BATSRUS, to which it is coupled. However, they have plans for allowing stand-alone runs. In this case we can do a climatological run (Fok reports that it runs 3x real time on a single processor)
- DISCUSSION: Can we create an Open Source Radiation Belt Community? (Weigel) There was a lot of enthusiasm for this idea, but we probably need a half-way house for collaborative repositories without them being fully open source. ViRBO already provides a SVN repository, but in some cases, it may make more sense to host it on a site that specializes in hosting software projects, because they can provide more services. See sourceforge.net, github.com, and code.google.com, for example. One of the most important things you can do is to make sure that you license your code. In some cases, no license is worse than overly restrictive license. Visit http://opensource.org/ for more information. NASA has some open source sites and a license, all summarized on Wikipedia.
2.2. Thursday, June 25th, (GEM Space Radiation Climatology emphasized)
2.2.1. Plenary Tutorial
Aaron Ridley: Climatological modeling using the AMIE code (2nd AM tutorial)
2.2.2. Recent science results from long-term simulations and data analysis
AM: 10:30-12:15 - Kearns
- Reanalysis of the radiation belt PSD for 1990-1991 using CRRES, Akebono, GPS, and GEO satellites UCLA-LANL reanalysis project update (Shprits)
- New analyses of long-term electron radiation belt data (Baker) The recently very quiet Sun has resulted in exploration of new state space for the belts, including outward motion of the outer belt and associated enlargement of the slot.
- Influence of solar wind density on ring current response (Weigel) There is a statistically robust signal for solar wind density in the response of the ring current. It's some kind of modulation of the convection electric field. The statistics do not yield a clear winner among various alternate "coupling" functions when time delays are used, as opposed to the traditional approach of computing a correlation coefficient using hourly averaged comparisons."
- Mass density database from GOES--11 years (Denton) Using GOES magnetometer data, reconstructed mass density for long interval. O+/H+ ratio implied, up to 40% O+ at solar max. Will follow-up with comparison to Young et al.
2.2.3. Implementation and methodology lessons learned
PM1: 1:30-3:00 - Kearns
- Recent results of performing reanalysis with various magnetic field models. (Ni) T96 and onward all give comparable results, but latest model appears to be best. More quantitative comparisons soon.
- SSA reconstruction of solar wind data, (Kondrashov) Impressive gap-filling revitalizes CRRES interval. Will seek funding to expand work to cover more solar wind parameters, Tsyganenko inputs, and entire OMNI history.
- Principal components of variation in the electron belts. (O'Brien) PCs of 15-year statistical reanalysis (TEM2b/Fellow-Humberto) are a little tricky to interpret, maybe due to using E/alpha/Lm rather than M/K/L*. Fastest diffusion is in pitch angle, slowest in energy, L in the middle. Also showed some ways to extract diffusion coefficients from the reanalysis, e.g. pitch-angle diffusion coefficient as a function of Kp.
2.2.4. Data/reanalysis sharing and future plans
PM2: 3:30-5:00 - Kearns
- Invited talk from Themis/SST (Larson) PPT Talk SST has enormous potential, works better than expected in trapped belts, but still needs work to address penetrating background.
- THEMIS SST comparisons with LANL-SOPA (Shprits) Match is not so great, yet
- The inter-calibration between LANL GEO SOPA and THEMIS SST e-measurements (Chen) Can use "fudge" factors to make them match, but don't know if these are robust at other L shells
- ViRBO Update (Weigel) ViRBO has more-or-less secured long-term funding. It's OK to rely on it now. New features are in the pipeline. Tell Bob what you want/need.
2.3. Related Posters
NGRSC and GEM/Climatology participants are encouraged to submit their posters for the Thursday poster session. Then, post your title here (or email it to Paul O'Brien).
1) Title: Simulations of Pitch-angle scattering of Relativistic Electrons With MLT-dependent Diffusion Coefficients Authors : Yuri Shprits, Lunjin Chen, and Richard Thorne UCLA, Los Angeles, CA, USA
2) Title: Versatile Electron Radiation Belt (VERB) Code Simulations Including Mixed Diffusion Authors: Dmitriy Subbotin, Yuri Shprits, Xin Tao, Binbin Ni
3) Title: RCM-VERB Coupled Simulations of the Dynamics of the Radiation Belts During Storms Authors: Dmitriy Subbotin, Yuri Shprits, Matina Gkioulidou, Viacheslav Merkin, Frank Toffoletto, Richard Thorne, Chih-Ping Wang, Larry Lyons
2.4. Contact Info
For questions regarding GEM Space Radiation Climatology or NGRSC, please contact Paul O'Brien, paul.obrien-at-aero.org.