CI和MCI干旱指数在宁夏的适应性对比  

Application Comparison of CI and MCI Drought Indexes in Ningxia

作　　者：高睿娜 王素艳 高娜[1,2] 左河疆 GAO Ruina;WANG Suyan;GAO Na;ZUO Hejiang(Key Laboratory for Meteorological Disaster Monitoring and Early Warning and Risk Management of Characteristic Agriculture in Arid Regions,CMA,Key Laboratory of Meteorological Disaster Preventing and Reducing of Ningxia,Yinchuan 750002,China;Ningxia Hui Autonomous Region Climate Center,Yinchuan 750002,China)

机构地区：[1]中国气象局旱区特色农业气象灾害监测预警与风险管理重点实验室,宁夏气象防灾减灾重点实验室,宁夏银川750002 [2]宁夏回族自治区气候中心,宁夏银川750002

出　　处：《干旱气象》2021年第2期185-192,共8页Journal of Arid Meteorology

基　　金：宁夏青年拔尖人才培养工程项目资助。

摘　　要：利用1981—2017年宁夏18个气象站逐日降水量、平均气温等资料以及各县市灾情和年度气候影响评估报告,以CI和MCI为干旱监测指标,从干旱日数、干旱强度、典型干旱事件3方面,对比分析2种干旱指数在宁夏气象干旱监测中的差异,探讨其适用性。结果表明:近36 a来,CI和MCI监测的宁夏中旱及以上等级干旱日数的年变化趋势一致,总体呈减少趋势,但CI的中旱及以上等级干旱日数比MCI偏多,且空间分布特征不尽一致,尤其在北部干旱区差异显著;CI和MCI干旱强度的变化趋势基本一致,但CI干旱强度比MCI偏强,且降水偏少越明显,CI比MCI强度越强。对于典型干旱事件,CI监测的干旱强度强,开始时间早,持续时间长,跨等级的跳跃现象明显,不符合干旱演变特征,而MCI的干旱监测效果更稳定,持续性更好,但干旱程度偏轻。宁夏降水量总体偏少,多集中在5—9月,且蒸发量大,由于MCI放大了更长时间(150 d)前降水的作用,使其干旱表征比实际干旱程度轻,总体上CI比MCI更适合于宁夏逐日气象干旱监测,但2种干旱指数均可反映宁夏中南部气象干旱日数和强度的时间演变特征。Based on daily precipitation and average temperature data at 18 meteorological stations of Ningxia from 1981 to 2016,prefectural and municipal disaster situations and annual climate impact assessment reports,CI and MCI were used as drought monitoring indicators,and their differences of application on meteorological drought monitoring in Ningxia from three aspects of drought days,drought intensity and typical drought events were compared and their applicability was explored.The results show that the annual change trends of drought days with moderate level and above monitored by CI and MCI were consistent in the past 36-year in Ningxia,they presented decreasing trend as a whole,but the drought days monitored by CI were more than MCI,and their spatial distribution characteristics were different,to certain extent,especially in northern arid region.The change trends of drought intensity monitored by CI and MCI were basically same,but the drought intensity of CI was stronger than MCI,and the less precipitation was,the stronger drought intensity of CI was.For typical drought events,the drought intensity monitored by CI was strong,the beginning was early,the duration was long,and the jumping phenomenon between drought levels was obvious,which wasn’t accordance with the evolution characteristics of drought.The monitoring effect of MCI was more stable and better sustainability,but the drought intensity was lighter.The precipitation was generally less in Ningxia,it concentrated from May to September,and the evaporation was large.Considering the influence of precipitation previous 150-day,the drought intensity monitored by MCI was lighter than actual situation.On the whole,CI was more suitable to daily meteorological drought monitoring than MCI in Ningxia,but two indexes could reflect the temporal evolution characteristics of meteorological drought days and intensity in central and southern Ningxia.

关 键 词：气象干旱综合指数(MCI) 综合气象干旱指数(CI) 适应性对比 

分 类 号：P426.616[天文地球—大气科学及气象学]