华中华东地区上空水汽平衡状况

Condition of Water Vapour Balance over the Middle-East China

华中华东地区，为我国纬度较低、海岸线最长的地区。该区雨水资源、地表水资源量均居全国之首。其维系因子———空中水汽，业经本文计算，其年总蓄留量＋１９７７４．５４亿ｍ３，相当水深１３９７ｍｍ，为水资源总量的１．７６倍，全国第一。该区任何季节，水汽输入量总大于输出量，是我国唯一没有水汽亏耗之季的地区。夏季（６～８月）为该区水汽最大输入季节（４３８６４．４亿ｍ３），也是最大输出季节（－３６１５０．９亿ｍ３）。通过外边界水汽输送，本区失去水汽，年总量－７０１．６亿ｍ３；通过国内边界获得来自比邻地区的水汽补给，年总量＋２０４７６．１４亿ｍ３。所以，该区是一藉比邻地区水汽补给以资对外境水汽的亏耗，并藉以维持本区降水过程及水资源保持的地区。本区终年向温带海域黄海、东海上空输送水汽，年总量２７８５３．３亿ｍ３；全年获自热带海域南海上空水汽，年总量＋２６５００．６亿ｍ３。

The Middle-East China is the region where the latitude is lower and the coast line is the longest in the country.The rain resources and the surface water resources in the region are both the rirst in China.The water vapour having been computed in held upover the region with mean annual value high up to+19 774.54×108m3,which amounts to 1 397mm of water layer and is 1.76 tines that of the regions water resources. The imported water vapour is more than the exported amounts in the region in any seasons,which is a region without dissipating season or water vapour in China.Summer(June to August) is the period with maximun amount of both imported water vater vapour (+43 864.4×108m3)and exported water vapour (-36 150.9×108m3).This region loss water vapour with mean annual value high up to-701.6×108m3 through out-boundaries and obtained the supplement of water vapour from neighboring areas through the inter-boundaries with annual total amounts to -20 476.14×108m3. Therefore,in this region the precipitation processes,the water resources and the dissipating of water vapour which import into foreign lands all are compensated by means of the supplement of water vapour from the neighbor area. In whole year,there is a net export of water vapour from the region into the Yellow Sea and East China Sea lying to the temperate meritime space with the amounts annual value 27 853.3×108m3,and into this region from the south China Sea lying to tropical sea area with the mean annual value high up to +26 500.6×108m3.