NSWP: Space Weather of the Thermosphere from CHAMP and GRACE Accelerometer Measurements

University Of Colorado At Boulder, Boulder CO

Investigators

Abstract

This project aims to characterize the variability of the thermosphere over a wide range of spatial and temporal scales. It will accomplish this by utilizing satellite observations from the CHAMP and GRACE satellites to derive total mass densities and cross-track winds from 2002 through 2008. These spacecraft data are particularly useful since observations are obtained almost continuously with better than 80-km resolution along the satellite track which extends from pole to pole. The database will be provided to the research community via the web, yielding a comprehensive view of space weather from solar cycle maximum through solar minimum. These datasets will then be used in a variety of other investigations. One of these will delineate and interpret the global magnetic storm response of the thermospheric densities, winds, and exospheric temperatures as a function of longitude, local time, and season. A similar study will be performed to elucidate the local time response of the density, winds, and exospheric temperatures for different levels of solar activity; this study includes an investigation of the relative contributions of the tides originating in the lower atmosphere relative to the tidal components forced in situ by solar EUV absorption. The dataset will also be used to investigate a variety of regional phenomena such as the equatorial ionization anomaly, the midnight temperature maximum, and wave 4 longitude structures recently observed in the ionosphere; these features can be examined for the global view of their seasonal, solar cycle, and magnetic activity dependences. The CHAMP satellite is scheduled to re-enter the atmosphere in 2009 and it may be possible to use data obtained during this period to derive vertical winds. The project will provide a cross-disciplinary training opportunity for graduate students in aerospace engineering and in space weather science and will help meet national needs in terms of training future engineers and scientists while addressing problems relevant to society such as orbital drag prediction and ionospheric effects on communication. It will also enable the research team to participate in the ESA mission GOCE which will further international collaborations. The space weather benefits include development of improved empirical density and wind models, validation and testing of first-principles models, conducting ion-neutral coupling studies using coincident orbital plane data from the DMSP satellites; and coordinated studies with data from the CNOFS satellite.