Print Email Facebook Twitter Thermospheric mass density variations during geomagnetic storms and a prediction model based on the merging electric field Title Thermospheric mass density variations during geomagnetic storms and a prediction model based on the merging electric field Author Liu, R. Lühr, H. Doornbos, E. Ma, S.Y. Faculty Aerospace Engineering Department Space Engineering Date 2010-09-03 Abstract With the help of four years (2002–2005) of CHAMP accelerometer data we have investigated the dependence of low and mid latitude thermospheric density on the merging electric field, Em, during major magnetic storms. Altogether 30 intensive storm events (Dstmin 100 nT) are chosen for a statistical study. In order to achieve a good correlation Em is preconditioned. Contrary to general opinion, Em has to be applied without saturation effect in order to obtain good results for magnetic storms of all activity levels. The memory effect of the thermosphere is accounted for by a weighted integration of Em over the past 3 h. In addition, a lag time of the mass density response to solar wind input of 0 to 4.5 h depending on latitude and local time is considered. A linear model using the preconditioned Em as main controlling parameter for predicting mass density changes during magnetic storms is developed: ? =0.5Em+?amb, where ?amb is based on the mean density during the quiet day before the storm. We show that this simple relation predicts all storm-induced mass density variations at CHAMP altitude fairly well especially if orbital averages are considered. Subject ionosphere (ionosphere-magnetosphere interactions)meteorology and atmospheric dynamics (thermospheric dynamics) To reference this document use: http://resolver.tudelft.nl/uuid:32b1d63f-99ce-4a7d-be08-170f76c89b67 DOI https://doi.org/10.5194/angeo-28-1633-2010 Publisher European Geosciences Union (EGU) ISSN 0992-7689 Source http://www.ann-geophys.net/28/1633/2010/angeo-28-1633-2010.html Source Annales Geophysicae, 28, 2010 Part of collection Institutional Repository Document type journal article Rights (c) 2010 The Author(s)CC Attribution 3.0 License Files PDF Doornbos_2010.pdf 623.55 KB Close viewer /islandora/object/uuid:32b1d63f-99ce-4a7d-be08-170f76c89b67/datastream/OBJ/view