【摘要】 以山东75个观测站伏期降水资料(1959—2005年)分析得到山东伏期旱涝在演变趋势有其独特性;500 hPa高度场距平分析表明,在中高纬尤其是贝加尔湖地区大气环流的异常对山东伏期的严重旱涝和洪涝形成起着重要作用;500 hPa高度距平场的EOF分析进一步证明,山东上游蒙古地区的冷空气活动和副高的强度是500 hPa高度场上影响山东伏期旱涝的两个最主要因子。更多还原

【Abstract】 Based on the rainfall data in mid-summer in Shandong,it is found that the flood and drought years are distinguished each other with Z index.There are common characters in mid-summer and the whole year,at the same time differences are found in mid-summer.Anomaly of the atmospheric circulation in the Lake Baikal region plays a very important role in the serious drought and flood in mid-summer in Shandong.We obtain the two most important patterns in 500hPa by EOF,which are the patterns of westerlies and subtropical high.更多还原