摘要
利用NCEP/NCAR 700 hPa风场再分析资料,定义了影响中国西部9月降水的区域风指数:西南、东南和偏北风3个风场面积指数,这可能是东亚季风变化的一个反映。研究了各个风指数之间的相互关系,表明它们之间既有一定联系,又有独立性。另外,还分析了各个风指数与西部9月降水的联系,结果表明,这些风指数与西部9月降水有很好的关系,西南风和东南风指数影响降水的区域有较大差异,西南风的影响范围大于东南风,西南风是影响西部秋季降水的主要因素,西南风减弱是导致高原东侧秋季降水减少的主要原因。
The regional wind index of influencing on the precipitation in September of West China has been defined using the 700 hPa u and v components of NCAR/NCEP reanalysis data in 1961-2006,they are three wind field area indices of southwest wind,southeast one and north one.These indices can reflect the change of East Asian monsoon.The relationships between the indices are studied,the results show that they have not only the correction relationship but also independence.Moreover,the relationship between the various wind indices and the precipitation in September of West China are very well.The results show that these indices have the very good relationship with the autumn rain of western China.There is an obvious difference for region of the influencing on autumn rain of western China region between the southwest wind and southeast wind indices.The coverage area of the southwest wind index is larger than that of the southeast wind index and the southwest wind is the factor to influent on the autumn precipitation in Western China.The weakening of southwest wind is the main cause of autumn precipitation reduces on east side of Tibet Plateau.
出处
《高原气象》
CSCD
北大核心
2010年第6期1501-1506,共6页
Plateau Meteorology
基金
国家自然科学基金项目(40675066)
甘肃省气象局"十人计划"共同资助
