Uncertainties in measurements of electron temperature and the estimation of F-region electron heat conduction from EISCAT data

• Published in: Journal of atmospheric and terrestrial physics 1996, Vol.58 (1), p.145-159
• Main Authors: Breen, A.R., Williams, P.J.S., Etemadi, A., Davda, V.N.
• Format: Article
• Language: English
• ISSN: 0021-9169
• DOI: 10.1016/0021-9169(95)00026-7

Heat conduction by electrons has an important influence on the temperature of the electron gas in the F2 region of the ionosphere. The rate at which the electron gas in a given volume is cooled by conduction is proportional to δ 2(T e 7 2 δh 2 The electron temperature T e can be measured as a function of height h by incoherent scatter but the estimates of δ 2(T e 7 2 δh 2 are highly sensitive to any errors in the measurements and to the fitting method used to calculate the second derivative. In this paper we derive a general formula for the random uncertainty in EISCAT temperature measurements using two independent methods and compare these with the errors quoted in the standard analysis programme. The heat flux and rate of cooling are then estimated by fitting a polynomial curve to the height profile of T e 7 2 , using the reduced − ξ 2. parameter to determine the order of the fitted polynomial justified by the accuracy of the data. The variation of heat flux with height and Covington index (S 10.7) is discussed.