基于SPEI的洮河流域气象干旱时空特征分析  

Analysis of spatiotemporal characteristics of meteorological drought in Taohe River Basin based on SPEI

作　　者：瞿德业[1] 杨明月 刘婷婷 杨山泉 谌越 夏搏 柴文博 丁春伟 QU Deye;YANG Mingyue;LIU Tingting;YANG Shanquan;SHEN Yue;XIA Bo;CHAI Wenbo;DING Chunwei(College of Geography and Environmental Science,Northwest Normal University,Lanzhou 730070,China;Lintao Meteorological Bureau of Gansu Province,Lintao 730500,China)

机构地区：[1]西北师范大学地理与环境科学学院,甘肃兰州730070 [2]甘肃省临洮县气象局,甘肃临洮730500

出　　处：《水利水电科技进展》2024年第5期32-40,共9页Advances in Science and Technology of Water Resources

基　　金：西北师范大学青年教师科研能力提升计划项目(NWNW-LKQN2020-05)

摘　　要：基于洮河流域1976—2020年逐月的气温和降水量资料,计算了季尺度和年尺度的标准化降水蒸散指数(SPEI),采用时间序列平稳性检验法和干旱频率法定量分析了季尺度和年尺度不同等级气象干旱频率的变化规律及空间分布特征,采用云模型分析了年尺度气象干旱时空分布的随机性与稳定性。结果表明:在季尺度上,四季的干旱频率都在30%左右,干旱主要发生在春冬两季;在年尺度上,流域以轻旱、中旱为主,轻旱、中旱发生频率高,重旱、特旱发生频率偏低,总体偏干旱;在空间分布上,干旱主要发生在流域的中下游区域;1976—2020年流域干旱化程度有所减弱,干旱化趋势稳定,干旱化程度波动较小。Based on the monthly temperature and precipitation data from 1976 to 2020 in the Taohe River Basin,the standardized precipitation evapotranspiration index(SPEI)values at seasonal and annual scales were calculated.The time series stationariness test method and drought frequency method were used to quantitatively analyze the variation pattern and spatial distribution characteristics of different levels of meteorological drought frequency at seasonal and annual scales.The randomness and stability of the spatiotemporal distribution of meteorological drought at the annual scale were analyzed using the cloud model.The results show that the frequencies of drought in all four seasons are about 30%,with droughts mainly occurring in spring and winter.At the annual scale,the basin is dominated by mild and moderate droughts,which have a high occurrence frequency,while severe and extreme droughts occur less frequently,indicating an overall dry tendency.In terms of spatial distribution,droughts occur mainly in the middle and lower reaches of the basin.During the period from 1976 to 2020,the degree of drought in the basin weakened,with a stable trend and small fluctuations in drought severity.

关 键 词：气象干旱 时空特征 SPEI 云模型 洮河流域 

分 类 号：P333[天文地球—水文科学]