News and Highlights
Here are some highlights taken from the 2007 CISM Annual Report:
  • CMIT 2.0 was shown to reproduce vertical ion drifts at Jicamarca. Data generated by CMIT closely matched observational data taken at the Jicamarca Radio Observatory.
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  • The thermosphere ionosphere nested grid (TING) model was used to investigate the rate of the recovery of the ionosphere/thermosphere system from geomagnetic storms. The model reproduced the main features of the differences between the recovery rates at solar maximum and solar minimum, so we also used it to investigate the causes of the differences and came to the following conclusions:
    1. The TING model indicates that there is faster TEC recovery at solar minimum than at solar maximum in regions in which negative storm effects occur which is in agreement with observations (Mendillo, 2006);
    2. The recovery rates in the model are the same at both extremes of the solar cycle in regions in which positive storm effects exist
    3. This difference in recovery rates results from the reaction rate of O+ with N2
    4. At solar minimum, increasing the temperature decreases the rate of this reaction (see Figure x+1), which in turn leads to faster recovery in regions where electron densities are depleted
    5. At solar maximum increasing the temperature increases the reaction rate, thus increasing the recovery time needed in regions of negative storm effects
    6. These recovery rates are sensitive to temperature changes during storms and very sensitive to the function used in the recovery rate – more exact knowledge of these two parameters would improve our ability to undertake space weather modeling in the ionosphere.
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