淮北地区2010年4月异常低温气候特征及成因分析

利用1961—2010年NCEP/NCAR再分析资料和4月淮北地区气温资料,用累积距平(CA)法、合成分析法对淮北地区气温的时空分布特征以及2010年4月淮北地区持续冷气候背景进行分析。文章分析了淮北地区4月冷、暖年的大气环流异常及要素场的空间分布特征。结果表明:淮北地区4月气温的年代际变化特征明显,在1990年前后发生了突变。贝加尔湖南部,100°E以东的华北地区中低层的冷空气活动与淮北地区4月气温高低存在很好的相关性,该地中低层冷空气强(弱),淮北地区4月气温低(高)。冷暖年,乌拉尔山暖脊、东亚大槽、西伯利亚高压等差异显著,说明以上是影响淮北地区4月气温异常的关键系统。另据分析,El Nino与淮北地区4月气温异常也具有很好的相关性。

Characteristics and causes of the abnormal low temperature in April of 2010 in Huaibei area

With the accumulation method of anomalies (CA) and synthetic analysis, this paper analyses spatial and temporal distribution of air temperature and continued cold weather background in April of 2010 in Huaibei area by using NCEP / NCAR reanalysis data of 1961-2010 and temperature data in Huaibei area in April. The article analyzes the atmospheric circulation anomalies in the cold and warm years of April, and the spatial distribution of element fields in Huaibei area. The results show that interdecadal air temperature in April changed significantly, and this change was fundamental round 1990. In the southern region of Lake Baikal, there was a positive correlation between the lower level cold air in north China(east of 100 °E) and the air temperature in Huaibei area. The more cold the air is, the more low the temperature is, and the reverse is true. In cold and warm years, the differences between warm ridge of Ural Mountains, the east Asian trough and the Siberian high pressure are significant, and it reveals that these critical systems are important enough to influence the abnormal temperature in April of Huaibei area. According to analysis, El Nino is well correlated with the temperature anomalies of Huaibei area in April.