钦州市7月旱涝的异常环流特征及前期强信号初探

Characteristics of Abnormal Circumfluence and Preliminary Study on Its Prophase Strong Signal for Drought and Flood in July of Qinzhou

选取钦州市7月8个重旱、13个重涝年,从天气气候角度着重对其前期冬季(12～2月)500hPa环流形势、环流特征指数以及青藏高原冬季积雪、北太平洋海温进行对比诊断分析,发现7月旱涝年前冬大型环流已出现较大的差异,其前一年12月的极涡强度、高原高度场,北太平洋赤道海温,以及前冬(12～2月)西太平洋副高面积指数、前冬青藏高原冬季积雪的多少,在旱涝年也有明显的不同,可作为旱涝发生的前期强信号,并确定其描述指标。

Taking the 8 serious drought years and 13 serious flood years in July of Qinzhou as examples to make a diagnosis analysis, from the point of weather climate, of 500hPa circumfluence situation in prophase winter (Dec. ~ Feb.), circumfluence characteristics indices, as well as winter firn on QinghaiZizang altiplano and marine temperature in North Pacific Ocean. The results shows that there has been big difference in formerwinter largesized circumfluence of the July drought and flood year, and it differs greatly between drought and flood years in polar eddy strength, altiplano height field, equator marine temperature in North Pacific Ocean, formerwinter West Pacific Ocean subhigh pressure area indices, and formerwinter firn on QinghaiZizang altiplano. All these are regarded as prophase strong signals and targets to describe can be determined.