基于SPEI指数的西北地区春旱时空分布特征  

Spatial and Temporal Distribution of Spring Drought in Northwest China Based on Standardized Precipitation Evapotranspiration Index

作　　者：陈斐[1] 杨沈斌[2] 王春玲[2] 王润元[1] 王鹤龄[1] 齐月[1] 

机构地区：[1]中国气象局兰州干旱气象研究所,甘肃省干旱气候变化与减灾重点实验室,中国气象局干旱气候变化与减灾重点实验室,甘肃兰州730020 [2]南京信息工程大学气象灾害预报预警与评估协同创新中心,江苏南京210044

出　　处：《干旱气象》2016年第1期34-42,共9页Journal of Arid Meteorology

基　　金：中国气象局兰州干旱气象研究所科研启动项目(KYS2014SSKY03);江苏高校优势学科建设工程(PAPD)项目共同资助

摘　　要：利用西北地区128个气象台站1961-2010年的气温和降水数据,计算了标准化降水蒸散指数（SPEI）,并结合气候统计分析和小波分析方法,探讨了西北地区春旱的时空分布特征。结果表明：（1）西北地区春旱程度重、次数多的地区位于新疆吐鲁番盆地、塔里木盆地、青海柴达木盆地和甘肃陇南地区,程度轻、次数少的地区位于新疆天山以北的东部地区;（2）区域平均状况下,春旱强度以0.259/10 a的速率显著增强,中旱发生频次以0.033次/10 a的速率显著增加。1980年代春旱强度和总频次降至最弱（少）,2000年代又增至最强（多）。不同省份内近50 a春旱也普遍呈显著增强趋势;（3）春旱发生频次具有3 a、9 a以及25 a以上尺度的周期波动特征,其中3 a尺度通过红噪声显著性检验,周期信号最可靠。由此可见,西北地区春季干旱具有明显的时空变化规律。In this paper temperature and precipitation data observed from 128 meteorological stations in Northwest China from 1961 to2010 were used to explore the spatial and temporal distribution of spring droughts. For this purpose,the standardized precipitation evapotranspiration index（ SPEI）,the intensity and frequency of spring drought were calculated and analyzed with methods of climate statistical analysis and wavelet analysis. The results are as follows：（ 1） In Turpan Depression,Tarim Basin of Xinjiang,Qaidam Basin of Qinghai and Longnan of Gansu Province,the spring droughts were most serious and occurred frequently,while in the eastern region of north Tianshan Mountain in Xinjiang it occurred least.（ 2） The average intensity of spring droughts over the study area strengthened significantly with a rate of 0. 259 per 10 years,and the frequency of moderate drought events increased significantly at a rate of 0. 033 times per 10 years. In the 1980 s the intensity of spring droughts fell to the weakest and the total frequency reduced,while in the 2000 s both of them rose to the strongest and the maximum. Meanwhile,spring droughts presented general increasing trend in these 5 provinces in recent 50 years.（ 3） The frequency of spring droughts displayed cyclical oscillation with scales of 3 years,9 years and 25 years above,and among them,the 3 years period passed through the significant test of red noise. The above results indicated that spring droughts in Northwest China presented distinct spatial and temporal variations.

关 键 词：标准化降水蒸散指数 变化趋势 周期波动 小波分析 

分 类 号：P467[天文地球—大气科学及气象学]