The Influence Of The Observation Distance On The Lightning Channel Temperature

The spectra for first return strokes of could-to-ground lightning discharge were obtained by a slit-less spectrograph in the Qinghai plateau of China. In this paper, the effect of the observation distance on diagnosis results of channel temperature was calculated and discussed by applying the Beer-Lambert law and considering the attenuation of spectral line intensity in transmission. The results show that there is some difference in channel temperature obtained at different observation distances.The observation distance is further, the temperature obtained is lower. Furthermore,the further distance we observed, the bigger error will be. So the correction on the temperature is more important under further observation distance. According to calculation and analysis, a semi-rational formula has been obtained which shows a relationship between the lighting channel temperature and the observation distance.The influence of the observation distance on lightning channel temperature could be eliminated by using the semi-rational formula.