Abstract:Taking Hubei Province for example, based on the surface meteorological da ta, GPS/Met data and radiosonde data, the water vapor resources are calculated. Fu rthermore, the deviation of the first two kinds of methods from the third is evaluated by setti ng the radiosonde result as standards. The results show that as f ollows.(1)The values of water vapor resources based on the surface data are slig htly smaller than that on the radiosonde data, and the annual average values at Enshi，Yichang and Wuhan Stations are about 4.7%,2.9% and 5.4% less than those b y radiosonde data,respectively.But their monthly change trends are coheren t.(2)At Yichang Station the deviation value of the result based on GPS data is a little higher than that on surface data in the same period, and the water vapor content is 5.6% more than that on radiosonde data but the result on the surface data is 3.5% less than that on radiosonde data.(3)About the effective vapor wat e r in precipitation days,the deviation values of the first two methods are respec tively only -1.4% and 8.4%.Therefore the precision of the method based on surfac e data and GPS data are higher and they can make up for the lack of radiosonde stations due to the adequate surface stations.In the mass, the precision of the method based on GPS is slightly less than that on surface data and this inadequ acy can be amended.