Abstract:

Based on the daily temperature of 76 weather stations in Northeastern China in summer during 1960-2013，NCEP/NCAR reanalysis data and the ENSO-Modoki Index, the variation trends of anomalous temperature in summer in Northeastern China were studied, and the possible relationship between the summer anomalous temperature events in Northeastern China and ENSO-Modoki events was analyzed by using the correlation analysis and composite analysis. The results are as follows: (1) The frequency of extreme high temperature events appeared a rising trend in Northeastern China in general，there were the peak values in the early 1980s and the mid to late 1990s, while that of extreme low temperature events showed a decreasing trend in general, and there was an obvious rising in the early 1990s. (2) Where the spatial distribution is concerned, the spatial differences of change trend of extreme temperature events were obvious in Northeastern China, the frequency of extreme high temperature event increased during 1960-2013 in most regions of the east of Northeastern China, and the frequency of extreme low temperature events near the Liaoning Peninsula increased, while that in northern part of Changbai mountain and southern part of Songjiang plain decreased. (3) The influence of El Nio-Modoki in last winter and La Nia-Modoki in spring was significant on the anomalous temperature event in summer in part of Northeastern China. When the El Nio-Modoki occurred in last winter, the frequency of extreme high temperature events in summer might decrease in some areas of Northeastern China, however, when the La Nia-Modoki occurred in spring, the frequency of extreme low temperature events in summer might decrease in some areas, while that of extreme high temperature events might increase.

Key words: the Northeastern China, extreme temperature events, summer, ENSO-Modoki

摘要：

利用1960～2013年中国东北三省76个台站夏季逐日气温数据、NCEP/NCAR再分析资料以及ENSO-Modoki指数，分析了东北地区夏季温度异常事件的时空变化特征，运用相关分析与合成分析相结合的方法探讨其与ENSO-Modoki之间的关系。结果表明：（1）东北三省夏季极端高温事件的频次波动较为明显，在1980年代初与1990年代中后期有明显峰值，而极端低温事件的频次呈下降趋势，但在1990年代初有1次明显上升；（2）从空间分布来看，极端高温事件的频次在东北三省东部的大部分地区以及大兴安岭北部地区呈上升趋势，而极端低温事件的频次在辽东半岛以及漠河附近有上升趋势，在长白山以北及松江平原以南地区则有下降趋势；（3）前一年冬季发生El Nio-Modoki或春季发生La Nia-Modoki，对黑龙江省与辽宁省的大部地区夏季出现温度异常事件影响较大。其中，前一年冬季发生El Nio-Modoki，当年夏季这些地区极端高温事件的频次可能会减少；春季发生La Nia-Modoki，上述地区夏季极端低温事件的频次会减少，而极端高温事件的频次可能会增多。

关键词: 东北三省, 极端温度事件, 夏季, ENSO-Modoki