宁夏地区气候暖干化与旱涝灾害趋势的关系

Relation of Climatic Dry-warming and Trend of Drought and Flood Disasters in Ningxia Region

依据宁夏地区11个气象站点1961—2012年实测气象数据,利用趋势线法、Z指数法、Mann—Kendall突变检验法及马尔科夫模型对宁夏地区气候变化特征和旱涝趋势进行了分析和预测。结果表明:(1)近52a来宁夏地区气候经历了冷湿—暖湿—暖干的转变,气温呈显著波动上升趋势(0.36℃/10a),远高于西部平均变暖率(0.2℃/10a);降水呈波动下降趋势,下降速率为9.94mm/10a。(2)旱涝灾害发生频次与气温变化具有一定的同步性。20世纪60—80年代中期气温变化不明显,旱涝趋势稳定;80年代中期到2006年气温大幅上升,旱涝灾害同步增加;2006—2012年增温趋势有所减缓,旱涝灾害相应减少。(3)运用马尔可夫模型对未来5a的旱涝状态进行了预测,结果表明,2013—2017年该地区降水处于"正常"的概率较大。在气候暖干化的大背景下,未来宁夏地区旱涝灾害发生频率有可能进一步增加。

Based on the data observed from 11meteorological stations in Ningxia Region from 1960to 2012, the characteristics of climate change were analyzed and the trends of droughts and floods were forecasted with methods of linear regression,Zindex,Mann—Kendall mutation test and Markov model.Results indicated as follows：（1）Ningxia regional climate changes experienced the three periods of cold—wet,warm—wet and warm—dry during the recent 52years.The temperature fluctuations showed a significant upward trend with a rate of 0.36℃/10a,far higher than the average warming rate（0.2℃/10a）in Western China.The precipitation fluctuations showed a downward trend with a decreasing rate of 9.94mm/10a.（2）The frequencies of droughts and floods and temperature changes occurred with a certain synchronicity：from the 1960sto 1980s,the change of temperature was not significant and the tendencies of droughts and floods were stable; from the mid-1980sto 2006,temperature increased substantially and droughts and floods increased simultaneously;and from 2006to 2012,warming trend occurred and the occurrence of droughts and floods was reduced correspondingly.（3）The state of droughts and floods in the next 5years was forecasted using the Markov model.From 2013to 2017,the probability of normal precipitation will be larger in Ningxia Region. In the backgrounds of warming and drying climate,the frequencies of droughts and floods are likely to increase further in the future.