HR: 11:05h
AN: SM12B-03 [Abstracts]
TI: Assimilation of Remote Ionospheric Measurements: Towards a Global Ionospheric Monitor
AU: * Mandrake, L
EM: mandrake@jpl.nasa.gov
AF: JPL/CalTech, 138-201
4800 Oak Grove Drive, Pasadena, CA 91109-8099
United States
AU: Wilson, B D
EM: brian.wilson@jpl.nasa.gov
AF: JPL/CalTech, 138-201
4800 Oak Grove Drive, Pasadena, CA 91109-8099
United States
AU: Mannucci, T
EM: tony.mannucci@jpl.nasa.gov
AF: JPL/CalTech, 138-201
4800 Oak Grove Drive, Pasadena, CA 91109-8099
United States
AB:
Explosive growth in the availability of ionospheric measurements from ground and space provide a fundamentally new
opportunity to image the ionosphere as never before. As examples, ground receiver TEC, occultation TEC, space-based
whole-Earth UV disc emission, in-situ measurements of electron density, and ground based ionosonde measurements of both
bottom-side profiles and critical parameters are all highly desirable and plentiful. However, these disparate measurements
must be blended together carefully, each having its own unique capabilities and challenges. Towards this end, we have
developed the Global Assimilative Ionospheric Model (GAIM). Utilizing two separate complementary assimilation approaches,
such observations are intelligently combined with prior climatological knowledge to yield the best estimate of the current
ionospheric state. The first, a variation of the Kalman filter recursive estimation approach, is optimized to produce the
best fit ionosphere with emphasis in regions of higher data density relying on a climatological background to assist in
regions of sparse data. The second, a 4-dimensional variational approach (4DVAR) instead adjusts physical driver estimates
(thermospheric densities and winds, electric fields, and solar radiation intensity in our case) to smoothly match incoming
data and spread its influence in a physically consistent manner. For ionospheric data in particular, estimation of these
ionospheric drivers is of paramount importance, as the ionosphere is a heavily dissipative system, and forecast without
proper drivers is nearly impossible. In this presentation, we shall explore results of merging ground-based GPS and
occultation TEC measurements and evaluate the system performance in various solar conditions.
DE: 2400 IONOSPHERE (6929)
DE: 2447 Modeling and forecasting
DE: 2467 Plasma temperature and density
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005