SA31D-2366
Cooling in the Post-Sunrise Equatorial Topside Ionosphere During the 22-23 June 2015 Superstorm
Wednesday, 16 December 2015
Poster Hall (Moscone South)
Marc R Hairston1, Russell Stoneback2, William Robin Coley2 and Roderick A Heelis3, (1)University of Texas at Dallas, Richardson, TX, United States, (2)University of Texas at Dallas, Dallas, TX, United States, (3)University Texas Dallas, Richardson, TX, United States
Abstract:
During the recovery phase of the 22-23 June 2015 superstorm multiple DMSP spacecraft observed two separate and short-lived (~ 30 minutes) events of localized cooling in the topside equatorial ionosphere (~840 km) in the post-sunrise region (between 6:15 and 7:30 local time). The ion temperatures dropped from the nominal 2000-3000° observed in these regions to 1000 to 1500°. This cooling effect was not observed on the corresponding duskside equatorial crossings of the DMSP spacecraft during this storm. Further, these cooling events do not normally occur during major storms; no such phenomenon was observed by DMSP during the March 2015 superstorm. Flow data from DMSP and the CINDI instruments on the C/NOFS spacecraft indicate these cooling events are associated with short-lived vertical flows bringing up cooler plasma from lower altitudes. The two cooling events correspond to large northward turnings of the IMF during the storm and these are being explored as a possible trigger mechanism.
