High and middle latitude neutral mesospheric density response to geomagnetic storms

We report the first observations of a high and middle latitude neutral mesospheric density response to geomagnetic storms. Inter-hemisphere mesospheric densities are estimated using data from meteor radars at Davis Station (68.6°S, 77.9°E), Svalbard (78.3°N, 16°E) and Tromsø (69.6°N, 19.2°E), which are located under the auroral zone; the Mohe (53.5°N, 122.3°E) and Beijing (40.3°N, 116.2°E) meteor radars, located in northern mid-latitudes, and the Microwave Limb Sounder (MLS) on the Aura satellite. Both case studies and a superposed epoch analysis indicate that geomagnetic storms can significantly influence mesospheric density, causing a greater than 10% decrease in the auroral zones, and a 5% decrease at higher mid-latitudes. With such large changes, it is reasonable to suspect that geomagnetic storms influence the dynamics of the high and middle latitudes mesosphere.