1971—2020年东北地区极端气候时空变化分析

东北地区是我国气候变化最显著的响应区之一,植被丰富,农业发达,气候变化对于当地可持续发展有重要意义。本文基于1971—2020年东北地区55个气象站点的气象日值数据,采用RClimDex模型计算极端气候指数,运用线性趋势、M-K检验方法探讨区域极端气候时空变化特征。得出如下结论:(1)研究区气温上升变化显著,FD0、TX10p显著减少,DTR减小;SU25、TX90p等表征极端高温事件指数显著增加,GSL延长。除气温极值外,突变点明显,空间变化一致性较强。(2)研究区极端降水量指数中CDD,RX1day呈现不显著下降趋势,其余极端降水指数表现为不显著上升,其中PRCP上升速率最大,各个极端降水指数突变交点众多,突变不明显。各分区的极端降水指数有着显著的空间差异。

Northeast China is one of the most significant response areas to climate change in China.With rich in vegetation and developed agriculture,climate change is of great significance to the local sustainable development.Based on the meteorological daily value data of 55 meteorological stations in northeast China from 1971 to 2020,the RClimDex model was used to calculate the extreme climate index,and the spatial and temporal change characteristics of regional extreme climate were explored by linear trend and M-K test methods.The following conclusions are drawn:(1)The temperature rise in the study area changed significantly,FD0 and TX10p decreased significantly,and DTR decreased;SU 25 and TX90p were characterized by significantly increased extreme heat events,and prolonged GSL.Except for the extreme temperature,the mutation point is obvious and the spatial change is strong.(2)In the extreme precipitation index in the study area,CDD and RX1day showed a non-significant downward trend,while the other extreme precipitation index showed a non-significant increase.Among them,PRCP had the largest rise rate,and each extreme precipitation index had many abrupt intersection points,and the mutations were not obvious.There are significant spatial differences in the extreme precipitation index of each partition.