针对气候变化背景下极端事件频发的现状,采用百分位阈值法、线性回归、M-K突变检验、显著性检验等方法分析了1961—2015年黄淮海地区极端气温及其发生日序的时空变化特征。结果 表明:(1)黄淮海地区的平均极端高温为32.6℃、极端低温为-9.0℃; 极端高温主要呈经向分布,极端低温呈纬向分布,极端低温受海陆位置影响较小。(2)1961—2015年极端高温呈高—低—高的变化趋势; 极端低温有显著升高趋势,其中京津冀地区升幅最大,气候倾向率均达到了0.6℃/10 a以上。(3)极端高温和极端低温的发生初日均呈提前趋势,但极端高温的终日推迟,而极端低温的终日提前结束。这表明黄淮海地区将出现秋季降温和春季升温提前趋势,将对冬小麦和夏玉米生产产生重大影响。
Considering the current situation of more extreme temperature events happened in the context of climate change, we described the characteristics of extreme temperature in Huang-Huai-Hai region from 1961 to 2015 based on daily temperature data. The methods including percentile thresholds, linear regression, m-k mutation test, significance test were employed to delineate the characteristics of extreme temperature and its occurrence sequence. Important results were obtained as follows.(1)In Huang-Huai-Hai region, the average extreme high temperature was 32.6℃, and the extreme low temperature was -9.0℃. Extreme high temperatures tended to distribute in a meridional direction, and extreme low temperatures distributed in a zonal direction, indicating that extreme low temperatures were less affected by the location of the sea and land.(2)From 1961 to 2015, the extreme high temperature showed a high-low-high trend, and the extreme low temperature showed the significantly increasing trend, of which the increase in Beijing-Tianjin-Hebei region was the largest, climate tendency rate reached above 0.6℃/decade.(3)The advance of the earliest day of extreme high temperature and the delay of the latest day indicated that that extreme high temperature might occur earlier and the duration prolonged. Extreme low temperature had the characteristics of early occurrence and early termination. It is indicated that the temperature in Huang-Huai-Hai region will fall earlier in autumn and rise earlier in spring, and will seriously affect the production of winter wheat and summer maize.
