我国大陆地区和近海海域能量收支分布及其季节变化的数值模拟研究

NUMERICAL SIMULATION OF ENERGY BUDGET DISTRIBU- TION AND ITS SEASONAL VARIATION IN CHINA MAINLAND AND SEA AREAS

应用美国宇航局Goddard地球观测系统四维资料同化系统、计算了我国大陆地区和近海海域 1 998年各月月平均能量收支各项和 1 0m气温、比湿及风矢量的地理分布特征 .模式计算结果表明 ,地表短波净辐射最强出现在夏季 ( 7月 )新疆和西藏中部地区 ,高值中心区可达 2 75W m2 ,在黄海东海海域春季 ( 4月 )最大 ,其值为 2 5 0W m2 左右 .地表长波净辐射最强出现在夏季 ( 7月 )我国西北地区 ,中心区值为 1 2 5W m2 ,我国近海海域在冬季 ( 1月 )最强 ,其值为 75— 1 0 0W m2 .我国近海海面 ,冬季 ( 1月 )潜热通量值高于一般月份 ,中心区值可达2 5 0W m2 ,夏季我国大陆西南、华北和东北一带为潜热通量高值区 ,其值为 1 2 5W m2 .月平均能量收支计算结果显示 ,在黄海、东海海域冬季 ( 1月 )净通量为海洋向大气输送 ,夏季 ( 7月 )则反之 ,新疆和西藏高原中部夏季为净通量正值区 .综合温度、湿度和风矢量场分布发现 ,夏季从南海向华东地区 ,孟加拉湾向印度次大陆有明显的水汽平流输送 。

The monthly mean values of energy budget, air temperature, specific humidity and wind vector at 10m over China mainland and sea areas for 1998 were calculated based on Goddard Earth Observing Data Assimilation System, NASA, United States. The results show that the largest net radiation of surface short wave appears in summer (July) in central areas of Xinjiang and Xizang, the magnitude in the high value central area reaches 275W/m 2. The largest net radiation appears in spring (April) in Yellow Sea and East China Sea, its maximum value is about 250W/m 2. The largest net radiation of the surface long wave appears in summer (July) in northwestern China, the value of the central area is 125W/m 2, and it appears in winter (January) in near China sea areas, the value is 75-100W/m 2. The latent heat flux in near China sea areas in winter (January) is higher than that in other months, its value in the central area occurs in southwestern, northern and northeastern China, its value is 125W/m 2. The calculation results of monthly mean energy budget illustrate that the net flux is transferred from ocean to atmosphere in winter (January) in Yellow Sea and East China Sea, and conversely in summer (July). The net flux value is positive in summer in Xinjiang and the central area of Xizang Plateau. The comprehensive analysis for distributions of temperature, humidity and wind vector shows that the water vapour is transported distinctly in summer from South China Sea to eastern China area and from Bay of Bengal to India subcontinent. The water vapour in southwestern area of Xizang comes from its southwestern direction.