近60年昆明市气候变化特征分析

Climate Change Trends and Characteristics of Kunming in Recent 60 Years

利用线性倾向率、Mann-Kendall非参数检验、滑动T检验（MTT法）和小波分析等数理统计分析方法,分析昆明市近60 a气候变化趋势和气候突变特征。结果显示：近60 a昆明市气候变化呈气温升高、降水量略微减少的暖干化趋势;气温上升率0.24℃/10 a,降水量下降率3.89 mm/10 a;干季增温强于雨季,而雨季降雨量下降趋势明显;2001~2010年是近60 a来昆明气温最高、降水量最少的10 a;昆明市气温变化包含5~10、10~15 a左右周期,其降水量变化有10~15 a左右的周期变化特征。

It is noted that the climate change is not globally uniform. Regional variations can be much larger and considerable spatial and temporal variations may exist among climatically different regions. In addition, climate change in a specific region or nation is of particular interest to that region and its economic activity. Ar- chival meteorological data of monthly air temperature and precipitation series were used to investigate climate change trends and characteristics in 1951-2010 of Kunming, which is located in the low-latitude plateau region of southwest China. The magnitude of a trend was estimated using linear regression analysis and the station sig- nificance of a trend was assessed by the M-K test and MT-test. Furthermore, the periodicity of a series was probed by Morlet wavelet transform. The results show that the climate change presents increasing air tempera- ture and decreasing precipitation in the past 60 years in Kunming region. The annual mean temperature in- creased at the trend rate of 0.24℃/10 a at the significance level a= 0.01. The annual precipitation decreased at the rate of 3.89 mm/10 a. The increasing trend of air temperature is more obvious in dry season than rainy sea- son, but decline rate of precipitation is obvious in rainy season than dry season. In the first 10 years of 21 st cen- tury, Kunming experienced much more severe temperature increase and precipitation decrease than in other periods over the observation period of 60 years. In addition, annual mean temperature of Kunming exits two evident characteristic time scale with 5-10 years and 10-15 years. The periodic variations of annual precipita- tion time series are localized in 10-15 years.