Abstract:
An international standard high-precision solar spectrometer was used to conduct an in-situ observation on solar spectra for one year during 2020 to 2021 in the Mt. Everest region. The results show that the surface instantaneous solar spectra and its integral values(global irradiance)frequently exceed the spectrum and solar constant for the top of the atmosphere,and the peak value of the local solar spectrum at noon in the summer solstice reached 2.211 W/(m~2·nm). The integral value of the surface observation spectrum of the Mt. Everest is about 15% higher than that of the sea level. The peak value of the daily mean spectrum reached 1.121 W/(m~2·nm)during the observation period. The monthly mean solar spectrum on the ground of the Mt. Everest was relatively concentrated,with narrow fluctuations. The highest monthly mean solar spectrum appeared in March,mainly due to the high surface reflection caused by snow. Based on the annual observation,it was found that among the global irradiance,the solar UVB accounted for 0.26%,UVA accounted for 5.33%,solar VIS accounted for 49.58% and infrared ray accountes for 44.83% in the Mt. Everest region. In order to compare the solar spectral characteristics in high altitude and low altitude regions,simultaneous observations on solar spectra of the Mt.Everest region and Beijing were carried out in the summer of 2021. The effects of atmospheric aerosols and water vapor on the solar spectra of the Mt. Everest and Beijing were studied by using the relevant data from the global Aerosol Robotic Network(AERONET).