近45a来中国西北年极端高、低温的变化及对区域性增暖的响应

Variability of Extreme high temperature and low temperature and their response to regional warming in northwest china in recent 45 years

利用中国西北五省(区)1960-2004年129个台站逐日最低、最高温度资料,从中统计出年极端高温发生频次、年极端低温发生频次、年极端高温强度、年极端低温强度以及年极端高温和低温开始和结束日期,分析了它们近45 a来的变化情况。结果表明:近45 a来中国西北年极端高温发生频次的增加趋势是明显的,而年极端低温发生频次的减少趋势更显著;中国西北近45 a来年极端高温的强度在不断增强,而极端低温的强度在不断减弱;近45 a来中国西北年极端高温开始日期逐渐提前,结束日期逐渐推迟,而年极端低温的开始日期在逐渐推迟,结束日期在逐渐提前;年极端低温发生频次的减少对于西北区域增暖的响应比年极端高温发生频次增加更显著,而年极端低温强度的减弱要比年极端高温强度的增强对西北区域性增暖的响应偏弱,年极端高温发生频次的增加同年极端高温强度的增强对西北区域性增暖的响应程度基本相当。

Most research have show that extreme climate event （drought, flood, typhoon, high temperature, low temperature and so on）bring about heavy economy loss, so in recent years extreme climate event have arouse the public wide concern, extreme temperature as a kind of extreme climate event have been researched by most specialist in recent years, but detailed study of extreme temperature of northwest china is few, so we count up frequency of annual extreme high temperature（frequency of exceed to 32 ℃ temperature）, frequency of annual extreme low temperature（frequency of lower than -15℃ temperature）, annual extreme high temperature intensity（average of annual maximum three exceed to 32 ℃ temperature ）, annual extreme low temperature intensity（average of annual maximum three lower than - 15℃ temperature ）, onset and upset date of annual extreme high temperature and low temperature from 1960- 2004 years 129 stations day- to- day maximum and minimum temperature data of northwest china and analyze spatial distribution feature and long - term change tendency of extreme high and low temperature frequency, long - term change tendency of extreme high and low temperature intensity and change feature of onset and upset date of annual extreme high temperature and low temperature. The result show that in recent 45 years increasing trend of annual extreme high temperature frequency is very clear, and decreasing trend of annual extreme low temperature frequency is more remarkable in northwest china; in recent 45 years annual extreme high temperature intensity is strengthen gradually, and annual extreme low temperature intensity is weaken gradually in northwest china, but the weak degree of annual extreme low temperature intensity is clear than strength degree of annual extreme high temperature intensity; in most areas onset date of annual extreme high temperature is advance gradually, and its upset date is postpone gradually in recent 45 years, on the contrary, onset date of annual extreme low temperature is postpone gradually, and its upset date is advance gradually; in recent 45 years warming tendency is very clear in northwest china, decreasing tendency of annual extreme low temperature frequency response to regional warming of northwest china is more remarkable than increasing tendency of annual extreme high temperature frequency, rising tendency of extreme low temperature intensity is more feeble than rising tendency of extreme high temperature intensity to response to regional warming of northwest china, however increasing tendency of annual extreme high temperature frequency is correspond to rising tendency of extreme high temperature intensity to response to regional warming of northwest china.