中南半岛春季气溶胶直接辐射强迫时空演变特征分析  

Spatial and Temporal Characteristics of Aerosol Direct Radiative Forcing during Spring in the Indo-china Peninsula

作　　者：何舒璇 樊雯璇[2] HE Shuxuan;FAN Wenxuan(Dehong Meteorological Bureau,Mangshi 678400,Yunnan,China;Department of Atmospheric Sciences,Yunnan University,Kunming 650091,Yunnan,China)

机构地区：[1]德宏州气象局,云南德宏678400 [2]云南大学大气科学系,云南昆明650091

出　　处：《高原气象》2024年第4期1039-1051,共13页Plateau Meteorology

基　　金：云南大学研究生科研创新基金项目(2020185);国家自然科学基金项目(41865001)。

摘　　要：中南半岛国家春季存在大量的生物质燃烧活动,生成的气溶胶会通过大气环流影响我国西南地区大气辐射收支,探究其对大气加热率的影响可为研究它对天气和气候的影响提供依据。基于MERRA-2再分析数据中逐时的气溶胶和晴空下的辐射通量等资料,首先分析其时空特征,其次利用EOF、合成分析等统计方法,讨论中南半岛气溶胶光学厚度(AOD)、地表气溶胶直接辐射强迫(ADRF)的时空演变特征及其与大气短波加热率的关系。结果表明:(1)在3-4月生物质燃烧季节,中南半岛与云南省均存在AOD极大值,它们的时间序列变化趋势具有较高的一致性,主要表现为老挝和越南北部地区AOD中心值超过1,受其影响云南省的AOD由北向南逐渐增强。(2)3-4月中南半岛生物质燃烧AOD与总AOD的高值中心一致,说明该区域气溶胶主要来源于生物质燃烧,老挝北部存在高达28 kg·m^(-1)·d^(-1)的生物质燃烧气溶胶的水平通量散度,能将气溶胶向东北方向输送至中国。(3)地表ADRF与AOD时空分布存在较高的一致性,3-4月老挝和越南的北部地区同样存在地表ADRF高值中心,其值可达-36 W·m^(-2)。EOF第一模态中,印度东北角与我国西藏东南部交界处、老挝、越南和泰国地区均为正位相区域,主要在3-4月出现极大值,2017-2018年间极值减弱,2019年再次增大。云南省地表ADRF时间变化趋势与中南半岛变化一致。(4)地表负ADRF和大气短波加热率的统计关系为:地表的净辐射通量减少越多,低层大气吸收短波辐射造成的加热越大,表明大气内气溶胶截留的短波辐射通量越多,该现象在700 hPa上最为明显,尤其是3-4月。Frequent biomass-burning activities occur in the Indo-China Peninsula in spring,and the aerosol generated will affect the atmospheric radiation budget of southwest China through the atmospheric circulation.Exploring its influence on the atmospheric heating rate can provide a basis for studying its influence on weather and climate.Based on the MERRA-2 reanalysis data of hourly aerosol and radiation flux under clear sky,their temporal and spatial characteristics were analyzed first.Secondly,using statistical methods such as EOF and synthetic analysis,the temporal and spatial evolution characteristics of aerosol optical thickness(AOD)and surface aerosol direct radiative forcing(ADRF)over the Indo-China Peninsula and their relationship with atmospheric shortwave heating rate were discussed.The results showed that:(1)During the biomass burning season from March to April,there was an extreme value of AOD in the Indo-China Peninsula and Yunnan Province.The time series trend also showed a high consistency.The central value of AOD in Laos and northern Vietnam was more than 1,and the AOD in Yunnan Province gradually increased from north to south due to its influence.(2)The high-value center of biomass combustion AOD in the Indo-China Peninsula from March to April was consistent with that of total AOD,indicating that it was mainly affected by biomass combustion aerosol at this time.The horizontal flux divergence of biomass burning aerosol is as high as 28 kg·m^(-1)·d^(-1)in northern Laos,which can be transported northeast to China.(3)The spatial and temporal distribution of surface ADRF and AOD showed a high consistency.The high-value center of surface ADRF also existed in the northern part of Laos and Vietnam in March and April,and its value could reach-36 W·m^(-2).In the spatial distribution of the first mode of surface ADRF in EOF,the northeast corner of India bordering in Tibet of China,Laos,Vietnam and Thailand are all positive phase regions,with maximum values appearing from March to April.The extreme values decrea

关 键 词：中南半岛 生物质燃烧气溶胶 气溶胶直接辐射强迫 大气短波加热率 

分 类 号：P422[天文地球—大气科学及气象学]