6/5 Special Seminar: The Sky is Falling!

in Seminars
June 2nd, 2014

Space Physics Seminar

Geomagnetic storm response at mid-latitudes: the sky is falling!

John Meriwether
Clemson University

Thursday, June 6, 2014
11:00 AM
Room CAS 500

Abstract:

It has become conventional wisdom that the thermosphere region at mid-latitudes will become affected by geomagnetic storm activity through transport of hot air and plasma from the polar region into the mid-latitude region. However, recent results obtained by NATION network of Fabry-Perot interferometers (FPI) provide evidence that this view is too simplistic. It now appears that there is a population of incoming fast oxygen atoms created by charge exchange of incoming energetic O+ ions that affect the wind and temperature results obtained by analysis of the FPI observations. Evidence suggesting this is based upon apparent detection of vertical winds as large as 200 ms-1 during a period of considerable activity featuring a red arc over southern Massachusetts and aurora over New Hampshire. Moreover, the temperature retrieved depends upon the observing direction whether parallel to the geomagnetic field line or perpendicular to it. What accounts for this apparent anomalous downward vertical transport seen by all five NATION FPI observatories? The mechanism proposed is that the thermal population of O atoms is contaminated by the fast O population.