南京近50年冬季低温冰冻积雪事件的气候特征

Climatic Characteristics of Low-temperature Freezing and Snow Calamities in Nanjing in Recent 50 Years

应用南京逐日观测资料分析了南京低温、冰冻和积雪灾害的变化特征及其与区域气候变暖的联系,得到如下结论:①低温、冰冻、积雪事件都存在一定的年代际和年际的周期变化;冬季平均最低气温和极端最低气温具有相似的周期性特征;积雪深度的年代际尺度的周期特征明显,但是较小尺度的年际周期不明显;②近50年来南京的低温、冰冻、积雪事件呈现波动下降的趋势;③南京年均气温和低温、冰冻、积雪事件之间存在较强的相关性与区域气候变暖关系密切。

Based on daily observation data of Nanjing,change characteristics of low-temperature,freezing and snow calamity and their relation with regional climate warming are analyzed.The result show that：（1） Low-temperature,freezing and snow calamities are of inter-decadal and inter-annual periodic changes in a certain degree.The average low temperature in winter and the extreme minimum temperature are similar in periodic features. Period characteristic of decades scale for snow depth is obvious,while annual period of smaller dimension is not obvious.（2） Low-temperature,freezing and snow calamities present a trend of fluctuating declining in Nanjing in nearly 50 years.（3） The annual average temperature in Nanjing is highly correlated with low-temperature,freezing and snow calamities,and is close with the regional climate warming.