春季青藏高原地区大气热源的气候特征分析

利用1948-2009年NCEP/NCAR逐日再分析资料采用倒算法计算了青藏高原地区大气热量源汇的值,分析了春季青藏高原地区大气热源的水平和垂直气候分布特征及时空变化特征.结果表明:春季青藏高原上空,大气热量源汇的整层积分为正值,即高原上空大气为热源,但在高原上空大气高层存在局部为冷源的分布.与周边地区相比较,高原对其上空大气的加热作用在三月份最为显著.春季3、4、5月青藏高原区域大气的加热存在一个自西向东逐渐扩展的过程.春季青藏高原东部和西部为大气热源年变化较大的区域,且高原东部和西部大气热源表现出反位相分布的特征.

Climatic character of heat sources in Tibetan Plateau

Using NCEP/NCAR daily reanalyzed data from 1948 to 2009 with the inverted arithmetic, the atmospheric heat sources of the Tibetan Plateau region are computed. Then the horizontal and vertical climatic character and the spatial-temporal pattern of the heat sources over the Tibetan Plateau are analyzed. The results are summarized as follows: In spring the atmosphere heat source bulk over the Tibetan Plateau is positive, but local cold sources lie in the high layer of the atmosphere over the portion of Tibetan Plateau. In March the heating action of the atmosphere over the plateau is the most remarkable compared with the surrounding regions. In spring there is a process of gradually expanding heat of the atmosphere from westward to eastward over the plateau. The western and eastern parts of the plateau are the active areas of the heat source changing in spring. It is found that the distribution of the spring heat source over the western and eastern plateau is opposite.