Simulation of hot oxygen effects on ground-based Fabry-Perot determinations of thermospheric temperatures

Abstract

The response of a ground-based Fabry-Perot interferometer (FPI) to predicted non-Maxwellian energy distributions of atomic oxygen in the F region is calculated. Analysis of the simulated profiles shows that the high-energy component of the non-Maxwellian profiles has a modest effect on ground-based measurements, raising the temperature derived from the Doppler-broadened profiles above that of the thermosphere in the 630 nm emission region. The effect is small compared to the uncertainties for an individual measurement but could be significant when large numbers of profiles are averaged in an attempt to reduce uncertainties in the determinations. However, the effect cannot account for the >100 K difference between the FPI determinations and values derived from empirical models such as the Mass Spectrometer Incoherent Scatter model. Copyright 2003 by the American Geophysical Union.