理想基流中大气波动多折射的数值试验

利用含非绝热加热的准地转正压涡度方程全球谱模式，采用４种热带海表温度异常作为热源和１６种理想基流，进行了理想基流中大气波动多折射的数值试验，积分时间为３０ｄ。得到：热源所激发的扰动通常能产生二支或三支波列，并由第一支波列分支出第二，三支波列，或第二支分支出第三支波列；对于有些基流，第一支波列维持两周或更长时间后消失，而留下其他波列；第二支波列往往最强，对于某些基流，两支流列有汇合聚集的趋势。

NUMERICAL EXPERIMENTS OF MULTI-REFRACTION OF ATMOSPHERIC WAVES ON PERFECT BASIC FLOWS

By using a global spectral model of quasi geostrophic barotropic vorticity equation including diabatic heating,a series of numerical experiments of multi refraction of atmospheric waves on perfect basic flows are run.The 16 perfect basic flows and 4 heat sources of tropical SSTA are considered and 30 days are taken for model integration. Results show that: (1) Disturbance excited by the heat source usually can have two or three branches of the wave trains, and the second or the third branch of the wave trains bifurcate from the first branch, or the third branch wave train bifurcates from the second. (2) For some basic flows, the first branch wave train disappears after maintaining two weeks or longer, and the other wave trains propagate still. (3) The second branch of wave train is the strongest in most cases and two branches of wave trains have the tendency of confluencing and focusing.