夏季青藏高原对于南亚平均季风环流形成与维持的热力作用

THE THERMAL EFFECT OF THE QINGHAI-XIZANG PLATEAU ON FORMATION AND MAINTENANCE OF THE MEAN MONSOON CIRCULATION OVER SOUTH ASIA IN SUMMER

摘要:

本文应用一个包括Rayleigh摩擦、Newton冷却及水平涡旋热力扩散的定常准地转34层球坐标模式来研究青藏高原对于南亚季风环流形成与维持的热力作用。计算结果表明:在北半球夏季,只考虑高原的地形强迫作用是不能形成南亚高压与南亚季风环流的,而青藏高原上空的非绝热加热对于南亚高压与南亚平均季风环流的形成与维持起了重要作用。计算结果还表明了青藏高原的非绝热加热对于形成一支横跨印度次大陆直到日本南部的强西南风带同样也起了重要的作用。

Abstract:

In this paper,a steady-state, quasi-geostrophic, 34-level spheircal coordinate model with Rayleigh friction, Newtonian cooling and the horizontal thermal diffusivity is used to investigate the thermal effect of the Qing-hai-Xizang plateau on formation and maintenance of the mean monsooa circulation over South Asia.The computed results show that only topographic effect of the Plateau can not form the South Asian high and the monsoon circulation over South Asia, but the diabatic heating over the Qinghai-Xizang plateau may play an important role for formation and maintenance of the South Asian high and the mean monsoon circulation over South Asia.The computed results also show that the diabatic heating over the Qing haiXizang Plateau play an important role for formation of a strong south west wind belt over the Indian peninsula,extending onto the southern of Japan.