Analysis on the Features of Energy Distribution on the Complicated Underlying Surfaces in Southeast Tibet

observation data from the land-atmosphere exchange experiment conducted in Nyingchi Region by the public-service (weather) scientific research project “observation and study on the land-atmosphere exchange on the complicated underlying surfaces in southeast Tibet” was applied to analyze the distribution features of turbulent heat flux on different underlying surfaces in typical sunny days and cloudy days. Results showed that: 1) in typical sunny days, both the daily peak and daily average of net radiation on the farmland underlying surface reached the maximum; in typical cloudy days, the daily peak of land surface net radiation changed slightly while the daily average decreased obviously; 2) in typical sunny days, the latent heat on the grassland, farmland, sunny slope and shade slope accounted for 0.4, 0.5, 0.32 and 0.27 of the net radiation respectively, the sensible heat accounted for 0.2, 0.1, 0.3 and 0.2 of the same respectively and the soil heat flux accounted for 0.17, 0.28, 0.03 and 0.24 of the same respectively; 3) in typical cloudy days, the latent heat on the grassland, farmland, sunny slope and shade slope accounted for 0.45, 0.43, 0.42 and 0.38 of the net radiation respectively, the sensible heat accounted for 0.17, 0.16, 0.62 and 0.12 of the same respectively and the soil heat flux accounted for 0.06, 0.17, 0.02 and 0.05 of the same respectively. The proportions of latent heat flux in net radiation on all the four kinds of underlying surfaces in Nyingchi Region were greater than those of the sensible heat flux in the same. Energy in this region was firstly used for water evapoproportionn and secondly for sensible heat exchange resulted from atmospheric motion and thirdly for the soil heating.