夏季南海－菲律宾上空低频热源对东亚环流影响的数值试验

NUMERICAL STUDY ON INFLUENCE OF SOUTH CHINA SEA/PHILIPPINES SUMMER OW FKEQUENCY HEATING SOURCES UP ON EAST ASIANA TMOSPHERIC CIRCULATION

采用钱永甫ｐ－σ五层坐标原始方程模式，研究南海－菲律宾地区上空的低频热源对不亚大气环流的影响。结果表明，当低频热源处于加热位相时，对流层上层澳大利亚上空西风加强，对流层低层１２０°Ｅ处越赤道气流增强，副高位置偏北，此时低层，东南风影响我国东部沿海地区的降水；冷却位相时，对流层上层澳大利亚上空西风减弱，对流层低层越赤道气流减弱，副高位置偏南，此时低层西南风造成我国东部沿海的降水。

Using Kuo-Qian p-σ incorporated coordinate five layer primitive equation medel,in-vestigation is undertaken of the influence of low-frequency convective heating sources over theSotith-China Sea to Philippines on East Asian atmospheric circtilation. Results show that withthe low frequency sources at heating(cooling)phase the west wind becomes strengthened(weakened)in the Atistralian upper troposphere and so does the 120°E cross equatorial flow in thelower troposphere,with the subtropical high positioned slightly northward(southward)of itsmean,a situation that allows the low-level SE(SW)wind to exert effects on rainfall over thescaboard of eastern China.