Influence of Sand-Dust on Solar Radiation in the Hinterland of Taklimakan Desert

In order to reveal the essential feature of radiation in extreme arid region of Northwest China,using the global radiation，direct radiation,diffuse radiation and meteorological data in the Tazhong station( in Takli-makan desert hinterland,83°39'E,38°58'N),the characteristics of atmospheric transparency coefficient,influence of sand-dust on solar radiation were analyzed by the statistical methods.The results show that: The coefficient of atmosphere transparency is better from October to December than other months,but it's worse in spring and summer.The index of the atmosphere transparency P₂ is the most ( least) in clear day ( sand storm day ) .The global radiation is more than 1000 W·m^-2 in clear day,dust day and sand blowing day,while,it is up to 700 W·m^-2 in sand storm day at most.The diffuse radiation is partly less than 400 W·m^-2,mainly between 100 and 200 W·m^-2in clear day.It is less than 600 W·m^-2 in dusty day mostly. The direct radiation is reduced by dust aerosol.The probability are 41.2%,72.5%,78.1% and 100% when direct radiation is less than 200 W·m^-2 during clear day,dust day,sand blowing day and sand storm day.The diffuse radiation is gradually concentration high value with the sand of the atmosphere is increased.The variation of every radiation is big in dusty day.The daily curve (value) of diffuse radiation is similar to the global radiation,which is reduced by dust aerosol is the same as the direct radiation.That suggests the atmosphere transparency is closely related to the global radiation,diffuse radiation and direct radiation.