Delayed response of the ionosphere to solar EUV variability II (DRIVAR II)

• Applicants: Professor Dr. Christoph Jacobi; Dr. Erik Schmölter
• Subject Area: Atmospheric Science
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 495912049

In Earth’s upper atmosphere, the absorption of solar UV and EUV radiation causes the creation of the ionosphere, which varies following the variations of solar radiation at these wavelengths of the solar spectrum. However, a delay occurs between these variations caused by the interaction of various physical and chemical processes. Especially the different ionization and recombination processes in the layers of the ionosphere but also transport processes have a significant influence on the delay. The role of these processes has been investigated in various studies, but so far these analyses have only studied separate aspects of the delay.The DRIVAR II project will investigate the aspects of the delay that have not been included in studies so far. This includes the variation of the delay at high and low latitudes or the role of coupling processes between thermosphere and ionosphere. Based on these results and previous studies, the project will provide a global and 3-dimensional description of the delay.The analysis will be based on established data sets (e.g., SDO-EVE, GOES, GUVI, radiation and Ionosonde data, or GNSS TEC maps), but will also consider new data such as GOLD and ICON observations. This variety of solar, thermospheric and ionospheric parameters will allow a detailed description of the delay. In addition, the Coupled Thermosphere Ionosphere Plasmasphere Electrodynamics (CTIPe) model and the Thermosphere-Ionosphere Electrodynamics General Circulation (TIE-GCM) model will be used for more detailed studies defining the processes responsible for the delay. The results of these investigations will then be used to make suggestions for optimizing these models as well as empirical models, if necessary.DRIVAR II is a joint project of the DLR Institute for Solar-terrestrial Physics in Neustrelitz (DLR-SO) and the Leipzig Institute for Meteorology (LIM). The DRIVAR II project will provide a more comprehensive and detailed analysis of the ionospheric and thermospheric processes that define the delayed ionospheric response. The studies will also improve the general understanding of processes in the upper atmosphere and are of interest for predicting ionospheric conditions.

• DFG Programme: Research Grants
• International Connection: USA
• Co-Investigator: Dr. Jens Berdermann
• Cooperation Partner: Dr. Mihail Codrescu, Ph.D.