The midlatitude electron density enhancement observed by DEMETER

Abstract

International audienceNighttime enhancements of the ionospheric F2 region electron density have been observed by ionosonde, incoherent scatter radar (ISR), GPS total electron content, and tomograpgic techniques. The French micro satellite DEMETER was launched on 29 June 2004. DEMETER is a sun-synchronized orbital satellite at 710 km altitude, and named after the Greek goddess of agriculture. The scientific mission is mainly designed to investigate the Earth ionosphere disturbances due to seismic and volcanic activities but also survey the electro-magnetic disturbances of planet linked with anthropogenic activity. Several scientific payloads are embedded in DEMETER, such as IMSC, IDP, ISL, ICE. In this paper, we study the electron density and electron temperature variations observed by ISL onboard DEMETER. ISL is the Langmuir probe produced by the European Space Technology and Research Centre to measure the density and temperature of thermal plasma. Based on long-term observations, the midlatitude enhancements of the electron density are also observed by DEMETER ISL data. We investigate 5 years data during 2005-2009 and find that the midlatitude enhancement mainly appear in nighttime from September to April. The detail results will be presented and discussed