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利用海洋大气完全耦合模式FOAM模拟研究了热带印度洋海盆模影响我国西北地区东部5月降水的异常及其物理机制.结果表明:当热带印度洋为暖海盆异常模态时,FOAM模式模拟的西北地区东部5月降水异常偏多,这与观测分析结果相一致.模拟发现春季热带印度洋暖海盆模态可在大气中引起类似“Matsuno-Gill Pattern”的异常响应,在对流层高层青藏高原西南侧形成异常高压,并在北半球中纬度沿高空急流轴形成异常遥相关波列,西北地区东部处于异常遥相关波列在东亚地区正异常中心的西部,正好为“西低东高”这一典型降水偏多的大气环流形势控制,对应对流层高层风场为明显的异常反气旋环流,气流辐散,低层有小范围的弱辐合,形成气流上升运动和水汽异常大值中心,引起降水偏多,模拟的海盆模引起的大气环流异常场与观测分析结果基本一致.FOAM模式对热带印度洋海盆模影响西北地区东部5月降水异常及其物理过程进行了较好的模拟验证.“,”Using fast ocean atmosphere model 1.5 (FOAM1.5),the numerical model stimulation of the tropical Indian Ocean Basin mode impacts on precipitation in east of northwest China in May are run and tested.The modeling precipitation and atmospheric circulation anomaly fields are basically similar to observational results,only with the anomaly system in East Asia a little eastward shifting.It is found that the tropical Indian Ocean SSTA warm Basin mode,being a heating source near the equator,can induce atmospheric circulation anomaly responses of the like “Matsuno-Gill Pattern”.The atmospheric circulation anomaly appears to be an anomaly high center over southwest of Qinghai-Tibetan Plateau,and this anomaly further spreads downstream to forming a remote correlation wave train along the jet axis in the mid-high latitude of north hemisphere.With the altitude increasing,the atmospheric anomaly responses are more significant.The east of northwest China is just located under the anomaly circulation pattern of “east high and west low” of anomaly wave train over East Asia,with wind being strong anticyclone and divergence at high level and weak cyclone and convergence at low level.And accompanying with upward motion,it is advantage for more precipitation.Therefore,FOAM1.5 model experiment verified observational results of the tropical Indian Ocean SSTA impacts on precipitation of east of Northwest China basically.