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Highly time-resolved aerosol characteristics during springtime in Weizhou Island

Journal of environmental Sciences 2018年第10期72卷 64-74页

作者： Jingying Mao Zhiming Chen Zhaoyu Mo Xiaoyang Yang Hong Li Yonglin Liu Huilin Liu Jiongli Huang Junchao Yang Hongjiao Li Scientific research Academy of Guangxi environmental Protection Institute for Environmental and Climate Research Jinan University Chinese research Academy of environmental Sciences

A single particle aerosol mass spectrometer was deployed to measure the changes of single particle species and sizes during March 2015 in Weizhou Island of the Beibu Gulf, Guangxi province, South China. In this campaign, a total of 3,100,597 particles were sized, and 25.8%particles with both positive and negative mass spectrum were collected and 24.8%characterized in combination with the ART-2 a neural network algorithm. The distribution of sized particles was mainly in from 520 to 600 nm, and the diameters ranging from 340 to1000 nm accounted for above 90%. Eight types of particles were classified: Elemental Carbon containing(EC), Organic Carbon containing(OC), EC and OC combined containing particles,Na containing particles, K containing particles(K), Levoglucosan containing particles,mineral containing particles, and Heavy Metal containing particles(HM). EC, OC and K were the major containing particles, which accounted for 84.3% in the eight types particles. The relative ratio and size distribution of the three types were EC(48.1%, 620 nm), OC(12.7%,440 nm), and K(23.5%, 600 nm), respectively. The three types of particles were a bit increasing ratios compared with those in clean periods during haze pollution periods.Combined with the back-trajectory results from the Hysplit-4 model and local pollution sources revealed that the ambient air quality on the Weizhou Island may be influenced by biomass burning in the Indochina Peninsula(biomass burning in the Indochina Peninsula)from the transportation on higher level atmospheric layer and by mainland of south China located northeast of Weizhou Island on the ground.

关键词： Characteristics Transportation Single particle aerosol mass spectrometer Biomass burning Weizhou Island

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VOC emission caps constrained by air quality targets based on response surface model:A case study in the Pearl River Delta Region,China

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Journal of environmental Sciences 2023年第1期123卷 430-445页

作者： Ya’nan Hu Bowen Shi Xin Yuan Chuanzeng Zheng Qing’e Sha Yufan Yu Zhijiong Huang Junyu Zheng Institute for Environmental and Climate Research Jinan UniversityGuangzhou 511436China Guangdong Polytechnic of environmental Protection Engineering Guangzhou 528216China

Because of the recent growth in ground-level ozone and increased emission of volatile organic compounds(VOCs),VOC emission control has become a major concern in China.In response,emission caps to control VOC have been stipulated in recent policies,but few of them were constrained by the co-control target of PM_(2.5)and ozone,and discussed the factor that influence the emission cap formulation.Herein,we proposed a framework for quantification of VOC emission caps constrained by targets for PM_(2.5)and ozone via a new response surface modeling(RSM)technique,achieving 50%computational cost savings of the quantification.In the Pearl River Delta(PRD)region,the VOC emission caps constrained by air quality targets varied greatly with the NOxemission reduction level.If control measures in the surrounding areas of the PRD region were not considered,there could be two feasible strategies for VOC emission caps to meet air quality targets(160μg/m^(3)for the maximum 8-hr-average 90th-percentile(MDA8-90%)ozone and 25μg/m^(3)for the annual average of PM_(2.5)):a moderate VOC emission cap with60%NOxemission reductions.If the ozone concentration target were reduced to 155μg/m^(3),deep NOxemission reductions is the only feasible ozone control measure in PRD.Optimization of seasonal VOC emission caps based on the Monte Carlo simulation could allow us to gain higher ozone benefits or greater VOC emission reductions.If VOC emissions were further reduced in autumn,MDA8-90%ozone could be lowered by 0.3-1.5μg/m^(3),equaling the ozone benefits of 10%VOC emission reduction measures.The method for VOC emission cap quantification and optimization proposed in this study could provide scientific guidance for coordinated control of regional PM_(2.5)and O_(3)pollution in China.

关键词： Volatile organic compounds Emission caps Air quality targets Response surface model Monte Carlo(MC)simulations

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Characterizations of organic compounds in diesel exhaust particulates

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Journal of environmental Sciences 2015年第8期27卷 171-183页

作者： Jaehyun Lim Cheolsoo Lim Sangkyun Kim Jihyung Hong Division of Global Environment research National Institute of Environmental Research Department of climate and Air Quality research National Institute of Environmental Research

To characterize how the speed and load of a medium-duty diesel engine affected the organic compounds in diesel particle matter（PM） below 1 μm, four driving conditions were examined. At all four driving conditions, concentration of identifiable organic compounds in PM ultrafine（34–94 nm） and accumulation（94–1000 nm） modes ranged from 2.9 to 5.7 μg/m3 and 9.5 to 16.4 μg/m3, respectively. As a function of driving conditions, the non-oxygencontaining organics exhibited a reversed concentration trend to the oxygen-containing organics. The identified organic compounds were classified into eleven classes： alkanes,alkenes, alkynes, aromatic hydrocarbons, carboxylic acids, esters, ketones, alcohols, ethers,nitrogen-containing compounds, and sulfur-containing compounds. At all driving conditions,alkane class consistently showed the highest concentration（8.3 to 18.0 μg/m3） followed by carboxylic acid, esters, ketones and alcohols. Twelve polycyclic aromatic hydrocarbons（PAHs）were identified with a total concentration ranging from 37.9 to 174.8 ng/m3. In addition, nine nitrogen-containing polycyclic aromatic compounds（NPACs） were identified with a total concentration ranging from 7.0 to 10.3 ng/m3. The most abundant PAH（phenanthrene）and NPACs（7,8-benzoquinoline and 3-nitrophenanthrene） comprise a similar molecular（3 aromatic-ring） structure under the highest engine speed and engine load.

关键词： Diesel particle matter Organic compounds Polycyclic aromatic hydrocarbons Nitrogen-containing polycyclic aromatic compounds

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Inter-comparisons of VOC oxidation mechanisms based on box model:A focus on OH reactivity

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Journal of environmental Sciences 2022年第4期34卷 286-296页

作者： Xiaoyun Yang Bin Yuan Zhe Peng Yuwen Peng Caihong Wu Suxia Yang Jin Li Min Shao Institute for Environmental and Climate Research Jinan UniversityGuangzhou 511443China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for environmental Quality Guangzhou 511443China Department of Chemistry and Cooperative institute for research in environmental Sciences University of ColoradoBoulderCO 80309USA

Volatile organic compounds(VOCs)oxidation processes play a very important role in atmospheric chemistry,and the chemical reactions are expressed in various manners in chemical mechanisms.To gain an improved understanding of VOCs evolution during oxidation processes and evaluate the discrepancies of VOCs oxidation schemes among different mechanisms,we used the total VOC reactivity as a diagnostic and evaluated tool to explore the differences for six widely used chemical mechanisms.We compared the total VOC reactivity evolution under high-NO_(x)xconditions for several sets of precursors,including n-pentane,toluene,ethene,isoprene and a mixture of 57 Photochemical Assessment Monitoring Stations(PAMS)species in a 0-D photochemical box model.Inter-comparison of total VOC reactivity of individual precursor simulations showed discrepancies to different extent of the oxidation schemes among the studied mechanisms,which are mainly attributed to the different lumping approaches for organic species.The PAMS simulation showed smaller discrepancy than individual precursor cases in terms of total VOC reactivity.SAPRC07 and RACM2 performances are found to better match the MCM for simulation of total VOC reactivity.Evidences suggest that the performance in simulating secondary organic products,OH concentrations and NO_(x)concentrations are related to the OH reactivity discrepancies among various chemical mechanisms.Information in this study can be used in selection of chemical mechanisms to better model OH reactivity in different environments.The results in this study also provide directions to further improve the ability in modelling total VOC reactivity with the chemical mechanisms.

关键词： VOCs Box model Chemical mechanism Total VOC reactivity VOC oxidation

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Historical variations in autochthonous and allochthonous sediment supplies to the largest freshwater lake in Central India

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International Journal of Sediment research 2022年第5期37卷 563-575页

作者： Nafees Ahmad Satinder Pal Singh Aasif Mohmad Lone Abul Qasim Ravi Bhushan Gyana Ranjan Tripathy Chinmay Shah Department of Earth and environmental Sciences Indian Institute of Science Education and Research Bhopal Geosciences Division Physical Research Laboratory Department of Earth and climate Science Indian Institute of Science Education and Research

Lacustrine sediment preserves high-resolution biogeochemical records of past variations in watershed processes controlling lake sedimentation. The current study explores historical variations in autochthonous and allochthonous sediment supplies to a large tropical freshwater lake system(Upper Lake, Bhopal) protected under the international Ramsar Convention of 2002 against anthropogenic pressures. For this purpose, multi-proxy biogeochemical data are presented for organic matter(total organic carbon, total nitrogen, phosphorous, and loss on ignition [LOI] at550°C), carbonate(LOI at 950°C), lithic sediment(aluminum, titanium, iron, calcium, magnesium,sodium, potassium, manganese, zirconium, niobium, hafnium, tantalum, thorium, uranium, and rare earth elements), and anthropogenic inputs(lead) measured in a 38 cm long sediment core retrieved from the lake. In addition to the lacustrine sediment core, the samples of catchment bedrock, surface soils, major stream sediment, and eolian dust collected from the lake periphery also are analyzed. The systematic biogeochemical excursions in the upper core section(top ～8 cm) indicate increased anthropogenic inputs, watershed denudation by agricultural activities, artificially reduced fluvial sediment supply, relatively increased dust inputs and lake eutrophication in the last few decades. The current study underscores the roles of anthropogenic land-use and wetland conservation practices in the rapid alteration of autochthonous and allochthonous sediment supplies to open aquatic ecosystems. Further, rising lake eutrophication levels despite a managed reduction in allochthonous sediment supplies seem challenging to control due to dissolved nutrient supply from urban sewage discharge and runoff from agricultural land in the watershed.

关键词： Upper Lake Sediment Geochemistry Sediment provenance Eutrophication Anthropogenic inputs

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A new portable in situ flume for measuring critical shear stress on river beds

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International Journal of Sediment research 2021年第2期36卷 235-242页

作者： Cheng He James Nodwell Taylor Quintin Rochfort David Nguyen National Water research institute Environment and Climate Change Canada Department of environmental Engineering University of Guelph

A new portable in situ flume(PISF) for measuring critical bed shear stress(CBSS) was developed in this study. The PISF consists of an open bottom sediment erosion chamber and an electrically-driven pump.Unlike most existing in situ flumes with similar designs, the new PISF does not rely on monitoring the flow conditions or particle density in the sediment erosion chamber; instead, it is a pre-calibrated flume.The calibration was performed by first determining CBSS of various selected sediment samples of known particle size and density(using the law of the wall), based on flow velocity-depth profiles measured in a6 m straight open-channel flume using a Particle Image Velocimetry(PIV) system. These same particles of known CBSS were then used in the new in-situ flume under controlled lab conditions to obtain a series of calibration curves of CBSS vs. pump electrical power. A wide variety of particle types and sizes(simulated sediments) were used in this two-step calibration procedure to widen CBSS measurement range and simulate cohesive force effects. The size of the PISF is much smaller and more practical than other similar devices as lamellar flow conditions are not required and it can be applied to a wide range of sediment types including cohesive sediments.

关键词： Sediment erosion In situ flume Critical bed shear stress Particle image velocimetry Law of the wall

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Anthropogenic monoterpenes aggravating ozone pollution

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National Science Review 2022年第9期9卷 178-185页

作者： Haichao Wang Xuefei Ma Zhaofeng Tan Hongli Wang Xiaorui Chen Shiyi Chen Yaqin Gao Ying Liu Yuhan Liu Xinping Yang Bin Yuan Limin Zeng Cheng Huang Keding Lu Yuanhang Zhang State Key Joint Laboratory of environmental Simulation and Pollution Control State Environmental Protection Key Laboratory of Atmospheric Ozone Pollution ControlCollege of Environmental Sciences and Engineering Peking University School of Atmospheric Sciences Sun Yat-sen University Guangdong Provincial Observation and research Station for climate Environment and Air Quality Change in the Pearl River Estuary Key Laboratory of Tropical Atmosphere–Ocean System Ministry of Education Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) institute of Energy and climate research IEK-8:TroposphereForschungszentrum Jülich Gmb H State environmental Protection Key Laboratory of Formation and Prevention of the Urban Air Complex Shanghai Academy of Environmental Sciences Institute for Environmental and Climate Research Jinan University

Monoterpenes have been known to have a critical influence on air quality and climate change through their impact on the formation of fine particles.Here we present field evidence that monoterpene oxidations largely enhanced local ozone production in a regional site in eastern China.The observed monoterpene was most likely from biomass burning rather than biogenic emissions,as indicated by the high correlation with CO at night-time,and the observed ratio of these two species was consistent with previously determined values from biomass burning experiments.Fast monoterpene oxidations were determined experimentally based on direct radical measurements,leading to a daily ozone enhancement of 4-18 parts per billion by volume(ppb),which was 6%-16% of the total ozone production,depending on the speciation of monoterpenes.It demonstrates that the previously overlo oked anthropogenic monoterpenes make an important contribution to 03 production in eastern China.The role could possibly be important at similar locations across China and other parts of the world that are characterized by massive emissions,especially where there are high NOxlevels.Our results highlight that anthropogenic monoterpenes should be taken into account when proceeding with the coordinated mitigation of O3and particulate matter pollution.

关键词： monoterpenes ozone pollution biomass burning anthropogenic emissions radical chemistry

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A threefold approach to rescue the 2030 Agenda from failing

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National Science Review 2023年第7期10卷 13-15页

作者： Prajal Pradhan Bauhaus Earth GmbH Potsdam institute for climate Impact research (PIK) Member of the Leibniz Association

Countries are not on track to meet the2030 Agenda for Sustainable Development [1] that calls for transformative changes to shift the world onto a sustainable and resilient path.The 2030Agenda comprises 17 Sustainable Development Goals (SDGs) and 169 targets to be achieved by 2030,balancing the three sustainability dimensions—social,economic,and environmental.So far,SDGs have had a limited transforma-tive impact [2] because of their selective implementation without considering their complex interactions.SDGs interact positively (i.***.synergies) or negatively(i.***.trade-offs) depending on contextand location-specific mechanisms.Failing to meet SDGs will negatively affect the lives of billions of people and worsen socioeconomic and environmental crises.

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A vehicle-mounted dual-smog chamber:Characterization and its preliminary application to evolutionary simulation of photochemical processes in a quasi-realistic atmosphere

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Journal of environmental Sciences 2023年第10期132卷 98-108页

作者： Wenlu Wang Yang Xiao Shijie Han Yang Zhang Daocheng Gong Hao Wang Boguang Wang Institute for Environmental and Climate Research Jinan UniversityGuangzhou 511443China Australia-China Centre for Air Quality Science and Management(Guangdong) Guangzhou 511443China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for environmental Quality Guangzhou 511443China

Smog chambers are the effective tools for studying formation mechanisms of air pollution.Simulations by traditional smog chambers differ to a large extent from real atmospheric conditions,including light,temperature and atmospheric composition.However,the existing parameters for mechanism interpretation are derived from the traditional smog chambers.To address the gap between the traditional laboratory simulations and the photochemistry in the real atmosphere,a vehicle-mounted indoor-outdoor dual-smog chamber(JNUVMDSC)was developed,which can be quickly transferred to the desired sites to simulate quasi-realistic atmosphere simultaneously in both chambers using“local air”.Multiple key parameters of the smog chamber were characterized in the study,demonstrating that JNUVMDSC meets the requirements of general atmospheric chemistry simulation studies.Additionally,the preliminary results for the photochemical simulations of quasi-realistic atmospheres in Pearl River Delta region and Nanling Mountains are consistent with literature reports on the photochemistry in this region.JNU-VMDSC provides a convenient and reliable experimental device and means to study the mechanism of atmospheric photochemical reactions to obtain near-real results,and will make a great contribution to the control of composite air pollution.

关键词： Vehicle-mounted dual-smog chamber photochemical processes quasi-realistic atmosphere composite air pollution Pearl River Delta region

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Arctic Sea Ice and Eurasian climate:A Review

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Advances in Atmospheric Sciences 2015年第1期32卷 92-114页

作者： GAO Yongqi SUN Jianqi LI Fei HE Shengping Stein SANDVEN YAN Qing ZHANG Zhongshi Katja LOHMANN Noel KEENLYSIDE Tore FUREVIK SUO Lingling Nansen-Zhu International research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Nansen environmental and Remote Sensing Center/Bjerknes Center for climate research climate Change research Center Chinese Academy of Sciences Uni research/Bjerknes Center for climate research Max-Planck institute for Meteorology Geophysical institute University of Bergen/Bjerknes Center for Climate Research

The Arctic plays a fundamental role in the climate system and has shown significant climate change in recent decades,including the Arctic warming and decline of Arctic sea-ice extent and thickness. In contrast to the Arctic warming and reduction of Arctic sea ice, Europe, East Asia and North America have experienced anomalously cold conditions, with record snowfall during recent years. In this paper, we review current understanding of the sea-ice impacts on the Eurasian climate.Paleo, observational and modelling studies are covered to summarize several major themes, including： the variability of Arctic sea ice and its controls; the likely causes and apparent impacts of the Arctic sea-ice decline during the satellite era,as well as past and projected future impacts and trends; the links and feedback mechanisms between the Arctic sea ice and the Arctic Oscillation/North Atlantic Oscillation, the recent Eurasian cooling, winter atmospheric circulation, summer precipitation in East Asia, spring snowfall over Eurasia, East Asian winter monsoon, and midlatitude extreme weather; and the remote climate response（e.g., atmospheric circulation, air temperature） to changes in Arctic sea ice. We conclude with a brief summary and suggestions for future research.

关键词： Arctic sea ice,Eurasian climate,Arctic Oscillation,review

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