Local time resolved dynamics of field-aligned currents and their response to solar wind variability
Monday, 23 May 2016
Maosheng He1, Joachim Vogt1 and Hermann Luhr2, (1)Jacobs University Bremen, Bremen, Germany, (2)Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, Potsdam, Germany
Abstract:
10 years of CHAMP measurements are condensed to study the dynamics of field-aligned currents (FACs) in separate magnetic local time (MLT) sectors through empirical modeling. Signaficant statistical evidences reveal that the FACs react in response to the changes in solar winds much farster on the dayside than on the nightside, 15–25 min versus 35–95 min. Furthermore, dayside FACs can be parameterized more accurately: R2 values maximize greater than 0.7 for FAC latitude and greater than 0.3 for FAC intensity, whereas the corresponding values on the nightside are smaller than 0.3 and 0.15, respectively. The results support the separation between directly driven coupling processes acting on the dayside and unloading processes controlling the nightside.
