Topside ionospheric electron temperature and density along the Weddell Sea latitude

摘要

It has been well known that the ionospheric electron density N_e is greater in the summer nighttime than daytime around the Weddell Sea region, which is named Weddell Sea Anomaly (WSA). This paper for the first time reports unusual increases (decreases) of the daytime (nighttime) electron temperature T_e at about 830km altitude over the WSA latitudes probed by Tatiana-2 during December 2009 to January 2010. Concurrent measurements at 660–830km altitude observed by Tatiana-2, Detection of Electro-Magnetic Emissions Transmitted from Earthquake Regions (DEMETER), and Formosa Satellite 3/Constellation Observing System for Meteorology, Ionosphere and Climate (F3/C) reveal the anticorrelation between T_e and N_e along the WSA latitudes in the daytime and nighttime. Based on F3/C N_e along the WSA latitudes observed at various local times, the associated T_e values are computed. The Tatiana-2 and DEMETER observations as well as the computed results show that T_e yield the maximum values over the WSA region during daytime and over the Indian and Atlantic Ocean area during nighttime. The maxima or minima in F3/C N_e and the computed T_e reveal eastward phase shifts.