A New Method to Retrieve Thermospheric Parameters From Daytime Bottom-Side Ne(h) Observations

Abstract

A new method to extract neutral composition (O, O2, N2), exospheric temperature Tex, vertical plasma drift ,W, and the total solar Extreme Ultraviolet (EUV) flux with   1050Å from routine ionosonde bottom-side electron density, Ne(h), observations has been proposed. The method can be used around noontime hours for all months of the year at middle latitudes where the ionospheric F-layer is formed by solar EUV radiation. The uncertainty of the retrieved neutral gas density coincides with the announced absolute uncertainty (10-15%) of Challenging Minisatellite Payload/ Space Three-axis Accelerometer for Research mission (CHAMP/STAR ) neutral gas density observations. The method provides statistically significant better results with Mean Relative Deviation (MRD) < 15% ; Root Mean Square (RMS) < 0.5 in a comparison with modern empirical models Mass-Spectrometer-Incoherent-Scatter ( MSISE00), Jacchia-Bowman 2008 (JB2008), and Drag Temperature Model 2013 ( DTM2013) (MRD>15% and RMS> 0.5). The thermospheric parameters retrieved for the St. Patrick Day magnetic storm and two so called Q-disturbance periods are given as an example of the method application. The retrieved neutral gas densities for the St. Patrick Day storm are compared to Swarm-B accelerometer observations. The proposed method may be considered as an useful tool for analyses of the state of the upper atmosphere under various geophysical conditions.