降水强迫对戈壁局地气候系统水、热输送的影响

EFFECTS OF RAINFALL FORCING ON THE TRANS PORT OF WATER AMD HEAT IN THE LOCAL CLIMATE SYSTEM OF GOBI

用黑河实验中化音站（戈壁）加强期的湍流脉动场资料对降水强迫影响戈壁局地气候系统水、热输送的过程进行了系统分析。结果表明：降水强迫会使戈壁局地气候系统出现暂时的不平衡状态，要重新回到平衡状态需要通过物质和能量的重新调配来实现。该过程可划分为４个阶段，各个阶段间的感热、潜热和水汽通量均有较大差异。从近地层水、热输送特征看，受降水强迫后非平衡状态的张弛时段大约为４ｄ。在整个张弛期间，地表接收到的降水约有２／３通过地表蒸发后输送到大气。

In this paper,using the data of turbulence observation of Huayin Station in Gobi area during IOP of HEIFE, the effects of rainfall forcing on the transport of water and heat in the local climate system of Gobi are analysed.The results show, that the local climate system becomes unbalanced due to the rainfall forcing, that the unbalanced state can return to the balanced state after rainfall through a new adjustment of substance and energy, that the process of the new adjustment can be divided into four periods,that the sensible heat flux, latent heat flux, and water vapour flux are very different with the periods, that relaxation time of the unbalanced state is about four days, and that about two thirds of rainfall are transported into atmosphere by the evaporation of ground surface and the rest may permeate the ground.