夏季副热带波谱能量分析及南亚高压的维持

THE WAVENUMBER ENERGETICS ANALYSIS IN THE SUMMER SUBTROPICS AND THE MAINTENANCE OF THE SOUTH ASIAN HIGH

本文应用波数空间的能量方程、采用欧洲中心客观分析资料(ECMWF),讨论了1982年夏季副热带对流层上部的能量学特征,着重分析了南亚高压的维持。结果表明,副热带能量循环与热带不同,海陆不均匀加热对超长波动能的作用比较小。在纬向气流～波动相互作用中、绝大多数波都失去动能。通过波～波相互作用、超长波1～2波及短波11～16波向中间尺度传输能量。 南亚高压有效位能的主要来源是有效位能的垂直输送;动能的主要来源是气压梯度力的作功。南亚高压能量的主要耗散机制是通过非线性作用向尺度较短的波动传输。

By using the equations of energetics in wavenumber domain, and with the ECMWF/WMO data, the energetic characteristics of the subtropical upper troposphere in 1982 summer are analyzed. Emphasis has been made on the maintenance of the South Asian high. Resuit shows that the energetic cycle in the subtropics, where the land-sea different heating is of less importance to the ultra-long wave kinetic energy, is different from that in the tropics. By the process of zonal mean flow-wave interactions, most of the waves lose their kinetic energies. And through the wave interactions, the waves of wavenumber 1~2 and 11~16 transfer energies to the medium-scale waves. The major source of the South Asian high potential energy is its vertical transport, and its kinetic energy comes mainly from the work done by the pressure gradient force. Through the process of nonlinear interactions, the South Asian high loses its energy to the shorter waves.