HR: 09:30h
AN: SA21B-07    [Abstracts]
TI: Modeling the Climatology of Equatorial Plasma Bubbles Observed by DMSP Satellites
AU: Retterer, J
EM: john.retterer@hanscom.af.mil
AF: AFRL/VSBXP, 29 Randolph Road, Hanscom AFB, MA 01731-3010, United States
AU: * Gentile, L C
EM: louise.gentile.ctr@hanscom.af.mil
AF: Boston College Institute for Scientific Research, 402 St. Clement's Hall 140 Commonwealth Avenue, Chestnut Hill, MA 02467-3862, United States
AB: The Defense Meteorological Satellite Program (DMSP) spacecraft, in circular near-polar orbits around 840 km altitude, occasionally observe depletions in plasma density when they cross the geomagnetic equator in the evening sector, at the times and places where low-density plasma plumes associated with equatorial spread F (ESF) radio-scintillation phenomena are expected to occur. Statistics for the frequency of observation of these depletions have been collected over the last eighteen years showing the seasonal and longitudinal variations of their rate of occurrence at various phases of the solar cycle. To better understand these probabilities, we have simulated these observations using first-principle models of the ambient ionosphere and bubble formation, using climatological drivers. The models are those which have been developed in preparation for the AFRL Communication/Navigation Outage Forecasting System (C/NOFS) mission. We will present maps of the frequency of occurrence of bubbles at 840 km altitude as a function of season and longitude calculated with the models and compare the results with the DMSP observations. These maps show the expected peaks in frequency of plasma bubbles near the equinoxes, with the additional winter peak in the American sector and the summer peak in the Pacific sector. The variation of bubble frequency with the phase of solar cycle will also be described.
DE: 2415 Equatorial ionosphere
DE: 2435 Ionospheric disturbances
DE: 2439 Ionospheric irregularities
DE: 2447 Modeling and forecasting
SC: SPA-Aeronomy [SA]
MN: 2007 Fall Meeting