摘要
为研究气象因子变化对标准化降水蒸散指数(standardized precipitation evapotranspiration index,SPEI)的影响,利用呼伦贝尔市5个气象站点1960~2015年逐日气象数据,通过FAO Penman-Monteith公式计算标准化降水蒸散指数,在分析月尺度干旱特征基础上,利用Sobol′全局敏感性方法分析SPEI对平均温度、温差、相对湿度、风速、冠层表面净辐射量和降水的敏感性。结果表明:呼伦贝尔市近56a来平均干旱强度为-1.19,且平均干旱强度以-0.03·10a-1速率不显著递减。极限干旱强度累计值多年波动范围为-7.33^-0.80,且每10a递减速率为-0.12。多年干旱频率波动范围为8%~58%,平均干旱频率为33%。尽管呼伦贝尔市整体上呈现不显著的干旱化趋势,但进入21世纪后,极端干旱事件发生频率增加较为明显。Sobol′全局敏感分析表明,除降水最敏感外,SPEI在春季、夏季、秋季、冬季次敏感因子分别为:平均温度、相对湿度、风速、平均温度。年际SPEI对降水、平均温度、相对湿度、风速、温差、冠层表面净辐射量的总敏感性分别为:0.71,0.13,0.12,0.11,0.03,0.01。年际SPEI与温差、相对湿度、降水的相关系数分别为-0.671(p<0.01),0.551(p<0.01),0.872(p<0.01),相关性强;平均温度、冠层表面净辐射量、风速与SPEI的相关系数分别为-0.151,0.086,-0.150,呈弱相关。通过SPEI与气象因子的敏感性及相关性分析可知,呼伦贝尔市年际SPEI受降水、相对湿度的影响较大,受冠层表面净辐射影响较小。
The Standardized Precipitation Evapotranspiration Index（SPEI） has been increasingly proposed for detecting and monitoring drought under the global climate, while its sensitivity to corresponding meteorological factors remains unclear. A global sensitivity analysis based on SPEI drought index was conducted from a data set of daily climate variables in 5 meteorological stations in Hulunbeier. The reference crop evapotranspiration was calculated by the FAO Penman-Monteith equation, and the SPEI sensitivity coefficients to key meteorological variables were determined by using Sobol’s global analysis method based on monthly scale SPEI. The results indicated that the average drought intensity was -1.19, and showed an insignificant decrease trend at the rate of-0.03·10 a-1. The cumulative of extreme drought intensity ranged from -7.33 to -0.80, and the descending rate was-0.12 per 10 years. The drought frequency fluctuated from 8% to 58% with the mean value of 33%. The extreme drought events had significantly increased immediately after entering the twenty-first Century, although an insignificant increase was detected in drought events for the last 56 years. Sobol’s sensitivity analysis showed that among the six meteorological factors,precipitation was the most sensitive one to the SPEI across the four seasons consistently, whereas the other most sensitive factors followed by precipitation were mean temperature in spring, relative humidity in summer, wind speed in autumn and mean temperature in winter, respectively. According to the total sensitivity coefficients of the annual SPEI to precipitation, mean temperature, relative humidity, wind speed, temperature difference and net surface radiation were： 0.71, 0.13, 0.12, 0.11, 0.03 and 0.01. The annual SPEI had strong correlations with temperature difference, relative humidity, precipitation by -0.671（p〈0.01）,0.551（p〈0.01） and 0.872（p〈0.01）, respectively. The correlation coefficients of average temperature, net surface radiation and wind speed
作者
迟道才
沙炎
陈涛涛
赵清
刘光辉
CHI Dao-cai;SHA Yah;CHEN Tao-tao;ZHAO Qing;LIU Guang-hui(College of Water Conservancy,Shenyang Agricultural University,Shenyang 110161,China)
出处
《沈阳农业大学学报》
CAS
CSCD
北大核心
2018年第4期433-439,共7页
Journal of Shenyang Agricultural University
基金
国家公益性行业(农业)科研专项项目(201303125)
国家自然科学基金项目(51679142
51709173)
辽宁省特聘教授基金项目(2013)
关键词
干旱
标准化降水蒸散指数
参考作物腾发量
敏感性
drought
standardized precipitation evapotranspiration index
reference crop evapotranspiration
sensitivity
