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Summary: The coupling between the ionized layers of the upper atmosphere and the thermospheric neutral gas takes place via ion drag force and is mediated.

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Presentation on theme: "Summary: The coupling between the ionized layers of the upper atmosphere and the thermospheric neutral gas takes place via ion drag force and is mediated."— Presentation transcript:

1 Summary: The coupling between the ionized layers of the upper atmosphere and the thermospheric neutral gas takes place via ion drag force and is mediated through magnetic field changes and both field-aligned (FAC) and ionospheric currents. Thus we talk about a coupled Magnetosphere-Ionosphere-Thermosphere (M-I-T) system. This electrodynamic system is driven by processes of momentum and energy transfer, mainly reconnection, between the highly variable solar wind and the interplanetary magnetic field (IMF) with the magnetosphere and by inner-magnetospheric plasma processes. The ionospheric conditions affect likewise the magnetospheric state. These processes are particularly important at high latitudes, but have inherently global impacts, notably for disturbance periods. They constitute a vital driving force for the transpolar thermospheric wind and thus to the global circulation and the worldwide energy budget. Matthias Förster GFZ German Research Centre for Geosciences, Helmholtz Centre Potsdam, Telegrafenberg, D-14473 Potsdam, Germany, mfo @ gfz-potsdam.de Dynamics and meso-scale structures at high-latitudes due to M-I-T coupling processes : modelling & data analyses DFG – SPP 1788 Dynamic Earth WorkshopGFZ Potsdam03-04 July 2014

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3 Cluster/EDI Average Convection Pattern DFG – SPP 1788 Dynamic Earth WorkshopGFZ Potsdam03-04 July 2014

4 Cluster/EDI Average Convection Pattern DFG – SPP 1788 Dynamic Earth WorkshopGFZ Potsdam03-04 July 2014

5 Neutral Wind Vorticity vs. IMF orientation DFG – SPP 1788 Dynamic Earth WorkshopGFZ Potsdam03-04 July 2014

6 Neutral Wind Vorticity vs. IMF orientation DFG – SPP 1788 Dynamic Earth WorkshopGFZ Potsdam03-04 July 2014

7 Vorticity of Wind Vector Distribution CHAMP accelerometer 01 Jan 2002 - 31 Dec 2003 North Hemisphere South Hemisphere Iijima and Potemra (JGR, Vol. 81, No. 34, 5971-5979, 1976, Fig. 6 ), obtained from TRIAD vector magnetometer data See: Förster, M., Haaland, S. E., and Doornbos, E. (2011): Thermospheric vorticity at high geomagnetic latitudes from CHAMP data and its IMF dependence. Annales Geophysicae, 29, 1, 181-186.

8 DFG – SPP 1788 Dynamic Earth WorkshopGFZ Potsdam03-04 July 2014 X17 Solar Flare Preceding Halloween Storm of 29-30 Oct Event study : IMF disturbance period of 28 October 2003

9 DFG – SPP 1788 Dynamic Earth WorkshopGFZ Potsdam03-04 July 2014 Neutral Wind (m/s) @ South Pole: Model & Observation Upper Atmosphere Model (UAM)

10 DFG – SPP 1788 Dynamic Earth WorkshopGFZ Potsdam03-04 July 2014 Neutral Wind (m/s) @ South Pole: Model & Observation Upper Atmosphere Model (UAM) See: Namgaladze, A.A., Förster, M., Prokhorov, B.E., and Zolotov, O.V. (2013), “Electromagnetic Drivers in the Upper Atmosphere: Observations and Modeling”. In: Bychkov, V. Golubkov, G., Nikitin, A. (Eds.), The Atmosphere and Ionosphere Elementary Processes, Discharges and Plasmoids, Springer, pp. 165-219.

11 DFG – SPP 1788 Dynamic Earth WorkshopGFZ Potsdam03-04 July 2014 Open Questions & Objectives  What is the nature of North-South asymmetries of the M-I-T system? (see, e.g. : Förster, M. and Cnossen, I. (2013), “Upper atmosphere differences between northern and southern highlatitudes: the role of magnetic field asymmetry”, Journal of Geophysical Research, vol. 118, issue 9, pp. 5951-5966)  Which consequences do result from this asymmetry for the global behaviour?  What are the concrete M-I-T interaction scenarios in meso-scales? The Swarm-S/C provide observations for several important parameters for these processes: Ion drift, Plasma density and temperatures, Neutral density and neutral (cross-track) wind, FAC. Numerical first-principle simulation appears to be a necessary tool for the physical understanding of these complex processes.  Need: Comprehensive data analysis & Further development of model tools. (one experienced scientist plus one PhD student ?)


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