摘要
采用线性趋势分析、Mann-Kendall、子波分析和功率谱分析等方法,分析了景泰县近50年年气温、降水的演变特征及对气候变暖的响应。结果表明:景泰年平均气温在1970年代中期发生了由降温到增温的转型,增温趋势明显,年平均气温增温率为0.32℃/10a。平均最低气温增温率高于最高气温,年平均日较差呈明显下降趋势,说明夜间增温高于白天增温。四季气温均呈上升趋势,但增温趋势表现出明显的季节非对称性,冬季增温最为显著,平均气温增温率达0.63℃/10a,为四季最高,秋季平均气温增温率为0.33℃/10a,春季为0.20℃/10a,夏季增温最小。降水量无明显的增减,但年际变化波动性较大。气温在1990年代中期发生增温的突变,降水没有突变现象发生。近50年来,景泰县气温的变化以8～10a、2～4a的周期振荡较强,年降水量变化的周期振荡以25a、9a、6a为主,在显著周期9a尺度上,两者为反位相变化结构,在5a时间尺度上自1990年代初期之后,降水与气温大致呈同位相变化。
In this paper, the change trends of annual air temperature and precipitation in Jingtai County, Gansu province, were analyzed using Mann - Kendall test method and Wavelet analysis based on the meteorological data observed by Jingtai Meteorological Station since recent 50 years. The results indicated that the annual air temper- ature changed from reducing to increasing in mid - 1970s. The increase rate of the annual mean air temperature was 0.32 ℃/10a in Jingtai County over the recent 50 years. Similar to the annual mean temperature, the maximum and minimum temperature had increasing trends. The asymmetric change of maximum and minimum was distinct, temperature increased mainly in night. The reason of obvious decrease in daily range was that the increase rate of minimum temperature was obviously higher than that of maximum temperature. There was no obvious change in annual precipitation, and moreover, big fluctuations among years. There were seasonal differences on variation of temperature. The temperature in winter, autumn and spring were significantly increased, the most obvious warming occurred in winter, but the warming trends in spring and summer were weak. By the abrupt change detecting with Mann - Kendall, the results showed that the annual mean temperature, annual mean maximum temperature and annual mean minimum temperature abruptly changed in 1994, 1996 and 1993, respectively. Wavelet analysis indicated that the annual mean temperature varied in periods of 8 - 10 and 2 -4 years, and precipitation varied in periods of 25, 9 and 6 years.
出处
《干旱区资源与环境》
CSSCI
CSCD
北大核心
2010年第2期89-95,共7页
Journal of Arid Land Resources and Environment
关键词
气候变化
突变检验
小波分析
气温
降水
景泰
climatic warming
abrupt change test method
wavelet analysis
precipitation
temperature
Jingtai County
