【摘要】 本文利用1961—1974年7月的平均资料,对45°N—40°S范围计算了各种平均经圈环流及加热场等物理量。所取的网格点为5°× 5°经纬度,垂直速度利用实际风计算,加热场是用热流量方程计算的。 由研究发现海陆分布及高原对平均经圈环流的影响是明显的,在南北半球大范围比较均一对称的下垫面上空,如欧非大陆、大西洋及东太平洋上空都存在一个典型的南北半球对称的Hadley环流。在北面是大陆高原,南面是海洋的亚洲地区,只有一个典型的季风环流。这是因为北半球副热带区的冷源变为热源,Hadley环流消失之故。西太平洋也有一类似的季风环流,这与这个地区存在较强的热源有关。北美季风环流很弱主要因为北美副热带陆地面积远比亚洲小。北半球全球的Hadley环流都很弱,主要是受季风环流的影响。 另外,还发现亚洲季风环流区,向上输送的能量很强,尤其高原地区更强更高,它在高空向东西两侧及南半球输送。更多还原

【Abstract】 In this paper, the mean meridional circulation and some physical par-ameters are calculated in the global latitude zone 45°-40°S for the July mean fields of 1961-1974.The analysed results show that the effect of the large scale land-sea distribution and Plateau on the mean meridional circulation is very clear.There exists a Hadley cell being symmetric in both Hemispheres, as soon as the underlying surface in large scale is symmetric in both Hemis-pheres no matter where is water or land, such as in Eastern pacific Oce-an, Atlantic Ocean and the Europe and Africa.In Asia there is a typical monsoon circulation.This is due to that the underlying surface of Asia in latitude belt 20°40° is land and Plateau which generates the heat source and ascending motion instead of the sink and descending motion in the subtropical belts in the other parts of the globe.InAmerica and western Pacific Ocean there are monsoon circulations too, but it is very weak over America.Owing to the effect of monsoon circulation the global mean Hadley cells in both Hemispheres are not sy-mmetric and the southern one is much stronger than the northern.The upward energy transportation in the monsoon circulation is very large, and it is largest in strength, the highest and the farthest in horiz-ontal over the Plateau.We think that the Qinghai Xizang Plateau plays a chimney effect for the energy transportation outward in the upper tropo-sphere.更多还原