惠州市5月高温特征及异常高温成因分析

Characteristics of high temperature in May and cause analysis of abnormal high temperature in Huizhou City

利用1953-2018年NCEP/NCAR日平均再分析资料和惠州市区逐日气象要素数据,统计分析了惠州市5月高温的气候特征,及1963年和2018年异常高温的成因。结果表明,惠州市5月出现高温天气年频率为15%;近66a间,惠州市5月日极端最高和月平均气温年变化均呈不显著的增加变化趋势;1963年和2018年5月出现了罕见的持续长时间的高温酷热天气,1963年以15d和38.1℃位列第一;5月气温异常偏高主要成因为对流层高层南亚高压中心偏东偏北,副热带高压长时间控制广东上空,同时低层弱的西南气流影响,形成了对流层高层辐合-低层辐散的高低空配置,有利于惠州高温天气的形成和维持。

Based on the NCEP/NCAR daily average reanalysis data from 1953 to 2018 and the daily meteorological elements data of Huizhou City, the climatic characteristics of high temperature in May and the causes of abnormal high temperature in 1963 and 2018 were analyzed. The results showed that the annual frequency of high temperature weather in May was 15% in Huizhou, and the annual changes of extreme maximum temperature and monthly average temperature in May had no significant increasing trend in recent 66 years. In1963 and 2018, rare hot weather with a long duration occurred in May, ranking first with 15 d and 38.1℃ in1963. The abnormal high temperature in May was mainly due to the fact that the center of South Asia High in the upper troposphere was more east and north, and the subtropical high controlled over Guangdong for a long time.At the same time, the influence of the weak southwest air flow in the lower troposphere formed the allocation of upper tropospheric convergence and lower tropospheric divergence, which was conducive to the formation and maintenance of high temperature weather in Huizhou.