中国北方典型强沙尘暴的地面加热场特征分析

Analysis on Surface Heating Field Characteristics of Typical Severe Dust-storms in Northern China

选取了中国北方16个典型强沙尘暴事件,利用NCEP/NCAR的日平均全球再分析网格点资料,对这些典型强沙尘暴事件的地面感热通量场、潜热通量场的分布特征进行了分析;同时对该区域中强沙尘暴的不同发生区地面的加热场也进行了对比分析。结果表明,通常在典型强沙尘暴事件发生区表现为正的感热通量和正的潜热通量;沙尘暴多发区域的南疆盆地表现为以潜热加热为主,西北区东部表现为以感热加热为主,华北地区北部则表现为感热和潜热加热同等重要;南疆盆地和西北区东部沙尘暴的发生受下垫面的影响较大,华北区北部沙尘暴的发生受下垫面的影响相对较小。

In order to be better understanding the characteristics of surface heating field in typical severe dust-storms, the reanalysis grid data of NCEP/NCAR of global daily average are used to analyze the distribution characteristics of the sensible and latent heat flux fields for 16 typical severe dust-storms in northern China. Meanwhile, a comparative analysis of surface heating field is done among the different areas where the dust-storms occur. The results show that the positive sensible and latent heat flux usually appear in the areas of dust-storms occurring. The Nanjiang Basin, the east of Northwest China and the north of North China are areas where the dust-storms frequently occur, the surface heating fields in these areas are mainly appeared as the latent heat heating, the sensible heat heating, and the sensible and latent heat heating respectively. The occurrence of dust-storms in the areas of Nanjiang Basin and the east of Northwest China is influenced by the underlying surface more than that in the areas of the north of North China.