Estimation of mesoscale thermospheric wind structure using a network of interferometers

We introduce a technique for estimating the regional thermospheric wind field from measurements made by a network of interferometers. Unlike previous work, this technique does not make assumptions about the functional form of the wind field and instead uses inverse theory to find the smoothest wind field that agrees with the measurements. This technique is general and applies to any network making radial velocity measurements. We show reconstructions of the thermospheric wind field over the eastern United States and over eastern Brazil, using data from two distinct networks of Fabry-Perot interferometers measuring the Doppler shift of the 630.0-nm airglow emission. In Brazil, we find direct evidence of a convergent wind field during the period of rapid thermospheric temperature increase associated with the equatorial midnight temperature maximum.