Global features of the disturbance winds during storm time deduced from CHAMP observations

摘要: A wind-driven disturbance dynamo has been postulated many decades ago. But due to the sparseness of thermospheric wind measurements, details phenomena could not be investigated. In this study we use CHAMP zonal observations from 2001 2005 investigate global features winds during magnetically disturbed periods. The is mainly westward, which increases with magnetic activity and latitude. At subauroral region, westward strongly enhanced in local time (MLT) sector afternoon midnight, relate plasma drift within polarization streams. middle low latitudes, largely independent season. Peak values occur at different MLTs for latitudes. That around 1800 MLT subauroal average about 200 m/s; 2300 MLT 80 m/s; 0300 MLT up 50 m/s. shift peak latitudes considered as a response when it propagates high Further by applying first superposed epoch analysis, show that responds delay sudden changes solar input, various latitudinal ranges. propagation auroral region equator 3–4 h. This consistent speed traveling atmospheric disturbances. Based on observations, try illustrate whole chain processes driving ionospheric effects lower