Differences between the Spring and Autumn Circulation of the Northern Hemisphere
Differences between the Spring and Autumn Circulation of the Northern Hemisphere
复制标题
北半球春季和秋季环流的差异
DOI：
--
复制
发表时间：
1987
期刊：
影响因子：
--
通讯作者：
J. Wallace
中科院分区：
文献类型：
--
作者：
E. Fleming;G. Lim;J. Wallace
摘要 北半球对流层平均气温年周期相位比常规气象季节（以4月和10月为中心）滞后约两个周期。因此，传统的春季比秋季更冷，通常更像冬天。当重新定义过渡季节以使它们更接近对流层平均温度的年周期时，就会出现一种独特的差异模式，这种差异以纬向对称成分为主。利用三个不同的气候数据集对这些差异进行了调查。春季的特点是极地地区气压较高，而对流层和平流层低层各个层面的 40°N 附近气压较低。这种差异模式的幅度随着高度的增加而增加。与气压模式一致，春季最强的纬向平均西风带位于赤道更远的地方，纬度 5-10°。
Abstract The phase of the annual cycle in the mean temperature of the Northern Hemisphere troposphere lags the conventional meteorological seasons (centered on April and October) by about two weeds. Hence, the conventional spring season is colder and generally more winter-like than the autumn season. When the transition seasons are redefined so as to bring them more closely into line with the annual cycle in tropospheric mean temperature, a distinctive pattern of differences emerges, which is dominated by a zonally symmetric component. These differences are investigated, making use of three different climatological datasets. Spring is characterized by higher pressure over the polar regions, and lower pressures in the vicinity of 40°N at all levels in the troposphere and lower stratosphere. The amplitude of this difference pattern increases with height. Consistent with the pressure pattern, the belt of strongest zonally averaged westerlies is located farther equatorward, by 5–10° latitude, during spring th...