武汉市盛夏高温气候特征和成因及预报

利用1950～2005年盛夏(7～8月)逐日武汉市最高温度、2002年和2003年6～8月T213格点风和垂直速度资料,分析了武汉盛夏高温的气候特征,研究了高温过程及西太平洋副热带高压活动特点。分析结果表明:20世纪50年代末至60年代初、60年代中期、70年代后期、90年代和2000～2005年为高温日数偏多的5个阶段。80年代高温日数偏少。对较大的时间尺度而言,强的高温集中在50年代后期至60年代以及90年代后期至2005年。强高温过程集中在7月下旬至8月上旬。西太平洋副热带高压持续稳定控制长江中下游,是造成高温及强高温过程的主要环流系统。选用ECMWF和T213温度和纬向风场预报产品,应用灰色预测方法建立了武汉市盛夏日最高温度预报模型,该模型试用于2003年和2006年盛夏高温预报,检验结果表明该模型提供的高温定量预报有一定的参考价值。

Climatic Characteristics, Causes and Prediction of Mid Summer High Temperature in Wuhan

Based on the daily maximum temperature of mid-summer(June to August)from 1950 to 2005,T213 grid wind data,and vertical velocity from June to August in the year of 2002 and 2003 in Wuhan,the climatic characteristics of mid-summer high temperature,high temperature processes and characteristics of the western Pacific subtropical high activities are studied.The analysis results show that:there were five high temperature periods with the number of high temperature days being greater than normal:the late 1950s to early 1960s,the middle 1960s,the late 1970s,and the 1990s to the early and mid 2000s.The number of high temperature days was less than normal in the 1980s.To larger time scale,the high-temperature weather occurred in the periods from the late 1950s to 1960s and the late 1990s to the early 2000s.The severe high temperature processes occurred usually on the period from late July to the early August.The western Pacific Subtropical High was the main influencing weather system for high temperature and severe high temperature processes,which controlled the middle and lower reaches of the Yangtze River steadily.With the data of temperature prediction products and zonal winds from ECMWF and T213 products,a method of gray forecasting is proposed to build a forecast model of mid-summer high temperature for Wuhan.The model was put to test in the mid-summers of 2003 and 2006,and it is proved that it has a certain reference value in quantitative forecasting of high temperature.