论文部分内容阅读
本文利用NCAR(美国国家大气研究中心)1976年太平洋各层风场资料,计算了0°—50°N,105°E—110°W范围内,7月850hPa,700hPa,500hPa,300hPa,250hPa和200hPa各层上的垂直运动,并与叶笃正等所作的太平洋上空夏季平均环流特征作比较得出:(1)常年Walker环流明显,而E1 Ni(?)o发生年热带西太平洋上升运动减弱,东太平洋空气下沉区变成了强上升区,Walker环流下沉区东移至110°W以东;(2)常年热带西太平洋Hadley环流不明显,沿160°E以东Hadley环流越来越清楚,呈向东递增的趋势,而E1 Ni(?)o年Hadley环流东西变化甚为复杂,Hadley环流的上升支并不在赤道附近,而移至10°N左右,明显较常年偏北,Hadley环流也变成自热带向副热带倾斜的环流圈;(3)E1 Ni(?)o发生年,夏季以淮河为中心的空气上升区变成下沉区,而37°N以北的华北地区仍是上升区,华北多雨,所以出现Ⅰ型降水。
In this paper, the wind field data of the Pacific Ocean in 1976 from the NCAR (National Center for Atmospheric Research) of the United States were used to calculate the wind field in the 0 ° -50 ° N, 105 ° E-110 ° W, July 850hPa, 700hPa, 500hPa, 300hPa, 250hPa and The vertical movement over the 200hPa layers is compared with the summer mean circulation characteristics over the Pacific Ocean by Ye Duzheng et al. (1) The perennial Walker circulation is obvious, whereas the annual warming of the El Niño (o) The Pacific air subsidence area has become a strong upwelling area, and the Walker circulation sinking area eastward to east of 110 ° W; (2) Hadley circulation is not obvious in perennial tropical western Pacific, and the Hadley circulation eastward along 160 ° E is more and more clear , Which shows a trend of increasing eastward. However, the Eastley change of Hadley circulation in E1 Ni (?) O is very complicated. The ascending branch of Hadley circulation is not around the equator but moves to about 10 ° N, apparently more northerly than that of the normal year. Hadley circulation (3) E1 Ni (?) O year, the summer as the center of the Huaihe River rose into the sinking area, and north of 37 ° N north of the area is still Ascending zone, rainy in northern China, so I type Ⅰ precipitation.