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Journal of Environmental Sciences 2022年第4期34卷 503-513页

作者： Lingyan Wu Xiaoye Zhang Junying Sun Yu Wang Junting Zhong Zhaoyang Meng state key laboratory of severe weather&key laboratory of atmospheric chemistry of CMA Chinese Academy of Meteorological SciencesBeijing 100081China

Air pollution in china is complex,and the formation mechanism of chemical components in particulate matter is still unclear.This study selected three consecutive heavy haze pollution episodes(HPEs)during winter in Beijing for continuous field observation,including an episode with heavy air pollution under red alert.Clean days during the observation period were selected for comparison.The HPE characteristics of Beijing in winter were:under the influence of adverse meteorological conditions such as high relative humidity,temperature inversion and low wind speed;and strengthening of secondary transformation reactions,which further intensified the accumulation of secondary aerosols and other pollutants,promoting the explosive growth of PM_(2.5).PM_(2.5)/CO values,as indicators of the contribution of secondary transformation in PM_(2.5),were approximately 2 times higher in the HPEs than the average PM_(2.5)/CO during the clean period.The secondary inorganic aerosols(sulfate nitrate and ammonium salt)were significantly enhanced during the HPEs,and the conversion coefficients were remarkably improved.In addition,it is interesting to observe that the production of sulfate tended to exceed that of nitrate in the late stage of all three HPEs.The existence of aqueous phase reactions led to the explosive growth sulfur oxidation ratio(SOR)and rapid generation of sulfate under high relative humidity(RH>70%).

关键词： Water-soluble ions PM_(2.5) Heavy haze pollution episodes(HPEs) Sulfate Nitrate Secondary aerosol processes

The Significant Contribution of Small-Sized and Spherical Aerosol Particles to the Decreasing Trend in Total Aerosol Optical Depth over Land from 2003 to 2018

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Engineering 2022年第9期16卷 82-92页

作者： Ke Gui Huizheng Che Lei Li Yu Zheng Lei Zhang Hujia Zhao Junting Zhong Wenrui Yao Yuanxin Liang Yaqiang Wang Xiaoye Zhang state key laboratory of severe weather&key laboratory of atmospheric chemistry of china meteorological administration Chinese Academy of Meteorological SciencesBeijing 100081China Institute of atmospheric Environment China Meteorological AdministrationShenyang 110166China

The optical and microphysical properties of aerosols remain one of the greatest uncertainties associated with evaluating the climate forcing attributed to aerosols.Although the trends in aerosol optical depth(AOD)at global and regional scales have been widely examined,little attention has been paid to the trends in type-dependent AODs related to aerosol particle properties.Here,using the aerosol optical component dataset from the Multi-angle Imaging SpectroRadiometer(MISR)instrument,we investigate decadal-scale trends in total aerosol loading as well as AODs for five aerosol components by particle size and morphology during 2003–2018 over land.Relationships between the total AOD(TAOD)trends and type-dependent AOD changes were examined,and the relative contribution of each type-dependent AOD to the overall TAOD trends was quantified.By dividing the TAOD values into four different aerosol pollution levels(APLs)with splits at 0.15,0.40,and 0.80,we further explored the relationships between TAOD changes and interannual variations in the frequency-of-occurrences(FoOs)of these APLs.Long-term trends in FoOs in the different APLs show that there was a significant improvement in air quality between 2003 and 2018 in most land areas,except South Asia,corresponding to a shift from lightly polluted to clean conditions.However,the effects of different APLs on TAOD changes are regionally dependent and their extent of correlation varied spatially.Moreover,we observed that the annual mean TAOD has decreased by 0.47%.a^(-1)over land since 2003(P<0.05).This significant reduction was mainly attributed to the continued reduction in small-sized(<0.7 mm diameter)AOD(SAOD)(-0.74%.a^(-1))and spherical AOD(SPAOD)(-0.46%.a^(-1)).Statistical analysis shows that SAOD and SPAOD respectively accounted for 57.5%and 89.6%of the TAOD,but contributed 82.6%and 90.4%of the trend in TAOD.Our study suggests that small-sized and spherical aerosols composed of sulfate,organic matter,and black carbon play a dominant role in determining interannual variab

关键词： AOD MISR Aerosol pollution levels Aerosol type Particle size and morphology

atmospheric Particle Hygroscopicity and the Influence by Oxidation state of Organic Aerosols in Urban Beijing

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Journal of Environmental Sciences 2023年第2期124卷 544-556页

作者： Sinan Zhang Xiaojing Shen Junying Sun Yangmei Zhang Xiaoye Zhang Can Xia Xinyao Hu Junting Zhong Jialing Wang Shuo Liu state key laboratory of severe weather&key laboratory of atmospheric chemistry of CMA Chinese Academy of Meteorological SciencesBeijing 100081China School of atmospheric Physics Nanjing University of Information Science&TechnologyNanjing 210044China

A hygroscopic tandem differentialmobility analyser(H-TDMA)was used to observe the sizeresolved hygroscopic characteristics of submicron particles in January and April 2018 in urban Beijing.The probability distribution of the hygroscopic growth factor(HGF-PDF)in winter and spring usually showed a bimodal pattern,with more hygroscopic mode(MH)being more dominant.The seasonal variation in particle hygroscopicity was related to the origin of air mass,which received polluted southerly air masses in spring and clean northwesterly air masses in winter.Particles showed stronger hygroscopic behaviour during heavy pollution episodes(HPEs)with elevated concentrations of secondary aerosols,especially higher mass fraction of nitrate,which were indicated using the PM2.5(particulate matter with diameter below 2.5μm)mass concentration normalised by CO mass concentration.The hygroscopic parameter(κ)values were calculated using H-TDMA(κhtdma)and chemical composition(κchem).The closure study showed thatκchem was overestimated in winter afternoon when compared withκhtdma,because the organic particle hygroscopic parameter(κorg)was overestimated in the calculations.It was influenced by the presence of a high concentration of hydrocarbon-like organic aerosol(HOA)with a weak water uptake ability.A positive relationship was observed betweenκorg and the ratio of oxygenated organic aerosol(OOA)and HOA,thereby indicating that the strong oxidation state enhanced the hygroscopicity of the particles.This study revealed the effect of local emission sources and secondary aerosol formation processes on particle hygroscopicity,which is of great significance for understanding the pollution formation mechanism in the North china Plain.

关键词： H-TDMA Hygroscopic parameter (κ) Organic aerosols Oxidation state Heavy pollution episode (HPE)

The macroscopic mechanisms and associated atmospheric precursor environmental capacities that lead to secondary fine particle pollution

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Science china Earth Sciences 2019年第12期62卷 2069-2082页

作者： Dahai XU Junming CHEN state key laboratory of severe weather and key laboratory of atmospheric chemistry of china meteorological administration Chinese Academy of Meteorological Sciences

This paper establishes the kinetic equations in atmospheric chemistry that describe the macroscopic mechanisms of secondary fine particle pollution generated by precursors during atmospheric self-purification.The dynamic and static solutions of these equations can be applied to calculate quantitative relationships between the concentration ratio of precursors and secondary fine particles as well as the physical clearance power of the atmosphere,chemical reaction rate,and the scale of a contaminated area.The dynamic solution presented here therefore corresponds with a theoretical formula for calculating the overall rate constant for the oxidation reaction of reducing pollutants in the actual atmosphere based on their local concentrations and meteorological monitoring data.In addition,the static solution presented in this paper reveals the functional relationship between the concentration of secondary fine particles and precursor emission rate as well as atmospheric self-purification capacity.This result can be applied to determine the atmospheric environmental capacity of a precursor.Hourly records collected over the last 40 years from 378 weather stations in china's Mainland as well as the spatiotemporal distribution sequence of overall oxidation reaction rates from precursors show that when the reference concentration limit of secondary fine particles is100μmol m-3,the atmospheric environmental capacity of total precursors canbe calculated as 24890×1010 mol yr-1.Thus,when the annual average concentration limit of given fine particles is 35μg m-3 and the ratio of sulfate and nitrate to 30%and 20%of the total amount of fine particles,the capacities of SO2,NOx and NH3 are 1255,1344,and 832(1010g yr-1),respectively.The clearance density of precursors for different return periods across china's Mainland under above conditions are also provided in this study.

关键词： atmospheric chemical kinetic equations Precursor of secondary fine particle Overall oxidation reaction rate atmospheric self-purification power atmospheric environmental capacity Clearance density Return period

Methane emission via sediment and water interface in the Bohai Sea,china

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Journal of Environmental Sciences 2022年第4期34卷 465-474页

作者： Kunpeng Zang Gen Zhang Xuemei Xu Nan Zheng Haoyu Xiong Haixiang Hong Kai Jiang Miao Liang College of Environment Zhejiang University of TechnologyHangzhou 310014China state key laboratory of severe weather&key laboratory of atmospheric chemistry of china meteorological administration Chinese Academy of Meteorological SciencesBeijing 100081China key laboratory for Ecological Environment in Coastal Areas National Marine Environmental Monitoring CenterDalian 116023China meteorological Observation Center China Meteorological AdministrationBeijing 100081China

Sediment is recognized as the largest reservoir and source of methane(CH_(4))in the ocean,especially in the shallow coastal areas.To date,few data of CH_(4)concentration in sediment have been reported in the china shelf seas.In this study,we measured CH_(4)concentration in sediment and overlying seawater columns,and conducted an incubation experiment in the Bohai Sea in May 2017.CH_(4)concentration was found to be ranged from 3.075 to 1.795μmol/L in sediment,which was 2 to 3 orders of magnitude higher than that in overlying seawater columns.The surface sediment was an important source of CH_(4),while bottom seawater acted as its sink.Furthermore,the net emission rate via sediment water interface(SWI)was calculated as 2.45μmol/(m^(2)·day)based on the incubation experiment at station73,and the earthquake may enhance CH_(4)release from sediment to seawater column in the eastern Bohai Sea.

关键词： Methane Porewater Sediment-water interface Rhizon sampler Earthquake

Significant contribution of carbonyls to atmospheric oxidation capacity(AOC)during the winter haze pollution over North china Plain

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Journal of Environmental Sciences 2024年第5期139卷 377-388页

作者： Xue Yang Gen Zhang Guang Pan Guolan Fan Houyong Zhang Xuan Ge Mingyue Du School of Municipal and Environmental Engineering Shandong Jianzhu UniversityJi’nan 250101China state key laboratory of severe weather&key laboratory of atmospheric chemistry of china meteorological administration Chinese Academy of Meteorological SciencesBeijing 100081China Shandong Jinan Ecological Environment Monitoring Center Ji’nan 250101China

atmospheric carbonyl compounds play significant roles in the cycling of radicals and have exhibited surprisingly high levels in winter that were well correlated to particulate matter,for which the reason have not been clearly elucidated.Here we measured carbonyl compounds and other trace gasses together with PM_(2.5)over urban Jinan in North china Plain during the winter.Markedly higher carbonyl concentrations(average:14.63±4.21 ppbv)were found during wintertime haze pollution,about one to three-times relative to those on nonhaze days,with slight difference in chemical composition except formaldehyde(HCHO).HCHO(3.68 ppbv),acetone(3.17 ppbv),and acetaldehyde(CH_3CHO)(2.83 ppbv)were the three most abundant species,accounting for~75% of the total carbonylson both haze and non-haze days.Results from observational-based model(OBM)with atmospheric oxidation capacity(AOC)indicated that AOC significantly increased with the increasing carbonyls during the winter haze events.Carbonyl photolysis have supplied key oxidants such as RO_(2) and HO_(2),and thereby enhancing the formation of fine particles and secondary organic aerosols,elucidating the observed haze-carbonyls inter-correlation.Diurnal variation with carbonyls exhibiting peak values at early-noon and night highlighted the combined contribution of both secondary formation and primary diesel-fuel sources.1-butene was further confirmed to be the major precursor for HCHO.This study confirms the great contribution of carbonyls to AOC,and also suggests that reducing the emissions of carbonyls would be an effective way to mitigate haze pollution in urban area of the NCP region.

关键词： Carbonyls Haze Observation-based model Source apportionment atmospheric oxidation capacity

2022汤加火山灰羽流的气溶胶光学、微物理和辐射特性

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Science Bulletin 2022年第19期67卷 2013-2021页

作者：桂柯车慧正田林王亚强石崇要文瑞梁苑新李雷郑宇张磊曾昭亮仲峻霆王志立张小曳 state key laboratory of severe weather&key laboratory of atmospheric chemistry of china meteorological administration Chinese Academy of Meteorological SciencesBeijing 100081China National Satellite meteorological Center China Meteorological AdministrationBeijing 100081China state key laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100081China

作为21世纪乃至近30年最强的火山喷发之一,2022年汤加火山喷发事件已经引起了广泛关注.研究表明,汤加火山喷发所产生的大量火山灰气溶胶突破对流层进入平流层,形成了一个顶部高度约为25~30 km的火山灰羽流.在喷发后的4天内,火山灰羽流... 详细信息

作为21世纪乃至近30年最强的火山喷发之一,2022年汤加火山喷发事件已经引起了广泛关注.研究表明,汤加火山喷发所产生的大量火山灰气溶胶突破对流层进入平流层,形成了一个顶部高度约为25~30 km的火山灰羽流.在喷发后的4天内,火山灰羽流在平流层环流的驱动下迅速向西移动了近10000 km.侵入平流层的火山灰气溶胶导致整个澳大利亚北部的大气气溶胶负荷显著增加,气溶胶光学厚度(AOD)在澳大利亚东北部海岸达到1.5,约为侵入前一日的15倍.此次汤加火山灰羽流主要以半径集中在~0.26μm处的细模态颗粒物为主,同时其体积峰值达到0.25μm^(3)μm^(-2).汤加火山喷发对平流层AOD和辐射平衡的影响显著,卫星观测到的平流层AOD的扰动高达0.6.这种扰动在很大程度上解释了区域性地表(大气层顶)的瞬时短波辐射强迫可达-105.0 W m^(-2)(-65.0 W m^(-2)).

关键词：火山喷发澳大利亚北部羽流火山灰卫星观测辐射平衡辐射特性 AOD

Influence of meteorological factors on open biomass burning at a background site in Northeast china

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Journal of Environmental Sciences 2024年第4期138卷 1-9页

作者： Yulong Wang Linlin Liang Wanyun Xu Chang Liu Hongbing Cheng Yusi Liu Gen Zhang Xiaobin Xu Dajiang Yu Peng Wang Qingli Song Jiumeng Liu Yuan Cheng state key laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China state key laboratory of severe weather&key laboratory for atmospheric chemistry Chinese Academy of Meteorological SciencesBeijing 100081China Longfengshan Regional Background Station China Meteorological AdministrationHeilongjiang 150200China Heilongjiang Climate Center Heilongjiang 150030China

Biomass burning(BB)is a very important emission source that significantly adversely impacts regional air quality.BB produces a large number of primary organic aerosol(POA)and black carbon(BC).Besides,BB also provides many precursors for secondary organic aerosol(SOA)generation.In this work,the ratio of levoglucosan(LG)to organic carbon(OC)and the fire hotspots map was used to identify the open biomass burning(OBB)events,which occurred in two representative episodes,October 13 to November 30,2020,and April1 to April 30,2021.The ratio of organic aerosol(OA)to reconstructed PM_(2.5)concentration(PM_(2.5)^(*))increased with the increase of LG/OC.When LG/OC ratio is higher than 0.03,the highest OA/PM_(2.5)^(*)ratio can reach 80%,which means the contribution of OBB to OA is crucial.According to the ratio of LG to K^(+),LG to mannosan(MN)and the regional characteristics of Longfengshan,it can be determined that the crop residuals are the main fuel.The occurrence of OBB coincides with farmers’preferred choices,i.e.,burning biomass in“bright weather”.The“bright weather”refers to the meteorological conditions with high temperature,low humidity,and without rain.meteorological factors indirectly affect regional biomass combustion pollution by influencing farmers’active choices.

关键词： Air pollution Biomass burning meteorological factors Organic trace Agricultural fires

Temporal Variation and Source Identification of Black Carbon at Lin'an and Longfengshan Regional Background Stations in china

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Journal of meteorological Research 2017年第6期31卷 1070-1084页

作者： Siyang CHENG Yaqiang WANG Xingqin AN state key laboratory of severe weather/key laboratory of atmospheric chemistry of china meteorological administration Chinese Academy of Meteorological SciencesBeijing 100081

Black carbon （BC） is a component of fine particulate matter （PM2.5）, associated with climate, weather, air quality, and people＇s health. However, studies on temporal variation of atmospheric BC concentration at background stations in china and its source area identification are lacking. In this paper, we use 2-yr BC observations from two background stations, Lin＇an （LAN） and Longfengshan （LFS）, to perform the investigation. The results show that the mean diurnal variation of BC has two significant peaks at LAN while different characteristics are found in the BC vari- ation at LFS, which are probably caused by the difference in emission source contributions. Seasonal variation of monthly BC shows double peaks at LAN but a single peak at LFS. The annual mean concentrations of BC at LAN and LFS decrease by 1.63 and 0.26 μg m 3 from 2009 to 2010, respectively. The annual background concentration of BC at LAN is twice higher than that at LFS. The major source of the LAN BC is industrial emission while the source of the LFS BC is residential emission. Based on transport climatology on a 7-day timescale, LAN and LFS stations are sensitive to surface emissions respectively in belt or approximately circular area, which are dominated by summer monsoon or colder land air flows in Northwest china. In addition, we statistically analyze the BC source regions by using BC observation and FLEXible PARTicle dispersion model （FLEXPART） simulation. In summer, the source regions of BC are distributed in the northwest and south of LAN and the southwest of LFS. Low BC concentration is closely related to air mass from the sea. In winter, the source regions of BC are concentrated in the west and south of LAN and the northeast of the threshold area of stot at LFS. The cold air mass in the northwest plays an important role in the purification of atmospheric BC. On a yearly scale, sources of BC are approximately from five provinces in the northwest/southeast of LAN and the west of LFS. These findings are helpful in reducing BC emission and

关键词： black carbon temporal variation source region atmospheric background station

The Pathway Toward Carbon Neutrality:Challenges and Countermeasures

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Engineering 2022年第7期8卷 1-2页

作者： Xiaoye Zhang Xiang Gao State Key Laboratory of Severe Weather&Key Laboratory of Atmospheric Chemistry of the China Meteorological Administration Chinese Academy of Meteorological SciencesBeijing 100081China state key laboratory of Clean Energy Utilization State Environmental Protection Engineering Center for Coal-Fired Air Pollution ControlZhejiang UniversityHangzhou 310027China

china’s solemn commitment to the world to strive for carbon neutrality by 2060 demonstrates the nation’s determination to take a new development route,different from its impressive achievements during the more than 40 years since 1979.Taking a green,low-carbon,and high-quality development path is also a strong manifestation of china’s determination to follow its consis-tent development belief of“conformity with morality,”with its emphasis on multilateral mechanisms and a willingness to make the best possible contribution to global concerns such as adaption to and mitigation of climate change.

关键词： Countermeasures neutral morality