0917号台风“芭玛”折向东南向移动原因分析

Analysis of typhoon Parma's track southeast turn

利用NCEP全球数据同化系统(GDAS)1°×1°分析资料,对0917号台风"芭玛"折向东南向移动原因进行了分析。结果表明,中高纬度环流调整是"芭玛"折向东南向移动的根本原因;0918号台风"茉莉"通过改变外围环境场的强度、形状对"芭玛"台风产生间接影响,而两台风之间逆时针互旋以及台风"茉莉"外围强大的环流对台风"芭玛"的直接作用是台风"芭玛"折向东南向移动的关键。对台风"芭玛"经纬向UV最大风速变化诊断分析表明,"芭玛"经纬向UV最大风速中心的转移对"芭玛"折向东南向移动有重要影响,经纬向UV最大风速差的变化对"芭玛"转向具有预示作用,经纬向最大风速差的合成风方向与台风中心未来移动方向有一定的关系。

Based on the analysis data of 1°x1° Global Data Assimilation System（GDAS） from NCEP,No.0917 typhoon Parma＇s path turning southeast are analyzed.The results show that the turning of Parma＇s path is mainly caused by the adjustment of Mid-latitude circulation.No.0918 typhoon Jasmine indirectly influences Parma’s path through changing the strength and shape of peripheral environmental field.The counter-clockwise rotation between the two typhoons and the direct influence of Parma＇s peripheral powerful circulation are key factors for Parms＇s track southeast turning.The analysis of Parma＇s UV maximum wind speed change in warp and weft direction shows that the transference of its center and the variation of its maximum wind speed difference respectively have important influence and indicating function,and its synthetic wind direction has a certain relationship with the typhoon＇s future motion way.