The Research About Vapor Resource Over Zhejiang Province Based On NCEP

Using the NCEP/NCAR monthly reanalyzed data ,the vapor resource over Zhejiang province is studied,of which include the interannual change of Precipitable water,vertical distribution characters of Precipitable water,the time and space distribution of water vapour flux,the water vapor convergence and the water vapor passage , the interannual change of net water vapor flux. As the climate of the earth is getting warmer, some specialists has studied the mutation of Zhejiang province's precipitation,while this article gives some different conclusions in Precipitable water and water vapor budget. The main results are as follows:(1) The content of vapor and net water vapor flux of Zhejiang province in summer is most abundant,and least in winter, the spring and autumn in general considerable. The water vapor is most abundant during 850hpa and 700hpa,the majority of the water vapor concentrates in the lower atmosphere. There are three vapor transportation belts impacting the content of vapor of Zhejiang,which are separately the southwest wind vapor transportation belt from the Bay of Bengal - Indochina, south wind from the South China Sea and southeast wind form the western Pacific .Apart from the eastern island of Zhejiang ,the other places are the regions of water vapor convergence,convergence intensity decreases from west to east, and change into the regions of divergence.(2) The change tendency of Precipitable water over Zhejiang province was first increased and then decreased, and sudden change phenomenon happened in the east and in the north and the time were both in 2001. Observing from the seasons, the atmospheric precipitation was increased gradually in winter and decreased in spring and increased-decreased-increased in summer and increased-decreased-increased in autumn. In the aspect of sudden change phenomenon, in spring it happened in the south in 2001.In summer it happened in the entire province, and the time in the north was in 1959 and 1969 ,the south was in 1958 ,the east was in 1971 , the west and central part were both in 1959. In autumn, it happened in the entire province except the south, the time in the north probably was in 1989 ,the east was in 1985 ,the west and the central part were both in 1990 The conclusion about the inter-annual change tendency of Precipitable water was nearly the same as the precipitation.(3) The water vapor in Zhejiang province mainly comes from the longitudes' transportation. The change tendency of net water vapor flux was firstly increased,then decreased,and then increased, there was almost no sudden change phenomenon in recent 60 years. In winter, the net water vapor flux change tendency was increased, and there was a sudden change phenomenon ,which had no obvious mutation point. In spring, the tendency was decreased, and the sudden change happened in 1964.In summer, the tendency was similar with the change curve of net water vapor flux annual, and sudden change phenomenon probably happened in 1949. In autumn, the tendency was increased ,then decreased, then increased and there was no sudden change phenomenon. The conclusion about the vapor in the air was nearly the same as the precipitation by analyzing the varying characteristics of Precipitable water.(4) In recent 60 years, the annual average of water vapor budget over Zhejiang province is about 1365.49 tons.