西北内陆上空水汽输送及其源地

The transport of vapour and its sources in Nothwest China

本文根据西北地区自然边界基本走向，采用不规则９边形作为水汽输送量计算边界，计算了１９８１—１９８６年暖季、寒季经由各边界的水汽输入与输出量．得出全年均有水汽净输入，暖季是＋１０１１．０１亿ｍ３、寒季是＋３９９．１９亿ｍ３．夏（６－８月）是水汽净输入的最大季节，年平均＋１５６０．５６亿ｍ３；秋（９—１０月）是水汽净输出季节，年平均－８５８．４５亿ｍ３．全年近６０％的水汽量经一、六、三边界入境，一边界占３０％，是水汽入境主边界；５０％的水汽量经五、四、六边界出境，五边界占２３－７％，是水汽出境主边界．结合天气形势分析，西北地区上空水汽主源地是北冰洋陆缘海域、大西洋及欧洲南方大陆．来自这些源地的水汽量占总量百分比：寒季（１１—３月），４１．２％；暖季（４－１０月），３９．３％；其次是西南方或东南方诸海域，寒、暖季分别为３２．７％、３０％．

The geographic borders of Northwest China are generalized with an irregular polyon and the imports exports of the vapour across the boundaries are computed for the period 1981-1986. The result shows that a definite amount of gaseous water has been stored in this area annually.Combining with the synoptic analysis,the sources of the vapour have been analized.