Retrieval of Atmospheric Water Vapor from MODIS and Analysis of Its Seasonal Variability over Chinese Continent

Atmospheric water vapor plays an important role in the high-energy thermodynamics of the atmosphere and the genesis of storm systems. Water vapor remote sensing can provide a detailed primary parameter within meteorological prediction models and climate models. The research selects four typical periods MODIS images and retrieves the contents of water vapor over Chinese continent in four seasons. Then the distributed maps of water vapor are drawn. Comparison with the measured values by radiosonde in aero logical stations, the retrieval values are a bit higher. The atmospheric water vapor contents over Chinese continent in winter are the lowest, the second for spring, the third for autumn, and that in summer are the highest. The whole spatial distribution of water vapor is the lowest in southwest of China, especially in Qinghai Tibetan Plateau, lower in northeast and north of China, higher in northwest of China, the highest in east and south of China. The spatial variability of water vapor content in China depends mainly on geographical location and terrain while its seasonal variability is relative with atmospheric circulation and monsoon.