Research article 12 Nov 2020
Research article | 12 Nov 2020
Sensitivity analysis of the surface ozone and fine particulate matter to meteorological parameters in China
Zhihao Shi et al.
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Ruqian Miao, Qi Chen, Manish Shrivastava, Youfan Chen, Lin Zhang, Jianlin Hu, Yan Zheng, and Keren Liao
Atmos. Chem. Phys., 21, 16183–16201, https://doi.org/10.5194/acp-21-16183-2021, https://doi.org/10.5194/acp-21-16183-2021, 2021
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We apply process-based and observation-constrained schemes to simulate organic aerosol in China and conduct comprehensive model–observation comparisons. The results show that anthropogenic semivolatile and intermediate-volatility organic compounds (SVOCs and IVOCs) are the main sources of secondary organic aerosol (SOA) in polluted regions, for which the residential sector is perhaps the predominant contributor. The hydroxyl radical level is also important for SOA modeling in polluted regions.
Meng Gao, Yang Yang, Hong Liao, Bin Zhu, Yuxuan Zhang, Zirui Liu, Xiao Lu, Chen Wang, Qiming Zhou, Yuesi Wang, Qiang Zhang, Gregory R. Carmichael, and Jianlin Hu
Atmos. Chem. Phys., 21, 11405–11421, https://doi.org/10.5194/acp-21-11405-2021, https://doi.org/10.5194/acp-21-11405-2021, 2021
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Light absorption and radiative forcing of black carbon (BC) is influenced by both BC itself and its interactions with other aerosol chemical compositions. In this study, we used the online coupled WRF-Chem model to examine how emission control measures during the Asian-Pacific Economic Cooperation (APEC) conference affect the mixing state and light absorption of BC and the associated implications for BC-PBL interactions.
Peng Wang, Juanyong Shen, Men Xia, Shida Sun, Yanli Zhang, Hongliang Zhang, and Xinming Wang
Atmos. Chem. Phys., 21, 10347–10356, https://doi.org/10.5194/acp-21-10347-2021, https://doi.org/10.5194/acp-21-10347-2021, 2021
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Ozone (O3) pollution has received extensive attention due to worsening air quality and rising health risks. The Chinese National Day holiday (CNDH), which is associated with intensive commercial and tourist activities, serves as a valuable experiment to evaluate the O3 response during the holiday. We find sharply increasing trends of observed O3 concentrations throughout China during the CNDH, leading to 33 % additional total daily deaths.
Lian Zong, Yuanjian Yang, Meng Gao, Hong Wang, Peng Wang, Hongliang Zhang, Linlin Wang, Guicai Ning, Chao Liu, Yubin Li, and Zhiqiu Gao
Atmos. Chem. Phys., 21, 9105–9124, https://doi.org/10.5194/acp-21-9105-2021, https://doi.org/10.5194/acp-21-9105-2021, 2021
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In recent years, summer O3 pollution over eastern China has become more serious, and it is even the case that surface O3 and PM2.5 pollution can co-occur. However, the synoptic weather pattern (SWP) related to this compound pollution remains unclear. Regional PM2.5 and O3 compound pollution is characterized by various SWPs with different dominant factors. Our findings provide insights into the regional co-occurring high PM2.5 and O3 levels via the effects of certain meteorological factors.
Jinlong Ma, Juanyong Shen, Peng Wang, Shengqiang Zhu, Yu Wang, Pengfei Wang, Gehui Wang, Jianmin Chen, and Hongliang Zhang
Atmos. Chem. Phys., 21, 7343–7355, https://doi.org/10.5194/acp-21-7343-2021, https://doi.org/10.5194/acp-21-7343-2021, 2021
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Due to the reduced anthropogenic emissions during the COVID-19 lockdown, mainly from the transportation and industrial sectors, PM2.5 decreased significantly in the whole Yangtze River Delta (YRD) and its major cities. However, the contributions and relative importance of different source sectors and regions changed differently, indicating that control strategies should be adjusted accordingly for further pollution control.
Mengyuan Zhang, Arpit Katiyar, Shengqiang Zhu, Juanyong Shen, Men Xia, Jinlong Ma, Sri Harsha Kota, Peng Wang, and Hongliang Zhang
Atmos. Chem. Phys., 21, 4025–4037, https://doi.org/10.5194/acp-21-4025-2021, https://doi.org/10.5194/acp-21-4025-2021, 2021
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We studied changes in air quality in India induced by the COVID-19 lockdown through both surface observations and the CMAQ model. Our results show that emission reductions improved the air quality across India during the lockdown. On average, the levels of PM2.5 and O3 decreased by 28 % and 15 %, indicating positive effects of lockdown measures. We suggest that more stringent and localized emission control strategies should be implemented in India to mitigate air pollutions.
Junjun Deng, Hao Guo, Hongliang Zhang, Jialei Zhu, Xin Wang, and Pingqing Fu
Atmos. Chem. Phys., 20, 14419–14435, https://doi.org/10.5194/acp-20-14419-2020, https://doi.org/10.5194/acp-20-14419-2020, 2020
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One-year source apportionment of BC aerosols in a coastal city in China was conducted with the light-absorption observation-based method and source-oriented model. Source contributions identified by the two source apportionment methods were compared. Temporal variability, potential sources and transport pathways of BC from fossil fuel and biomass burning were characterized. Significant influence of biomass burning in North and East–Central China on BC in the region was highlighted.
Jingyi Li, Haowen Zhang, Qi Ying, Zhijun Wu, Yanli Zhang, Xinming Wang, Xinghua Li, Yele Sun, Min Hu, Yuanhang Zhang, and Jianlin Hu
Atmos. Chem. Phys., 20, 7291–7306, https://doi.org/10.5194/acp-20-7291-2020, https://doi.org/10.5194/acp-20-7291-2020, 2020
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Large gaps still exist in modeled and observed secondary organic aerosol (SOA) mass loading and properties. Here we investigated the impacts of water partitioning into organic aerosol and nonideality of the organic–water mixture on SOA over eastern China using a regional 3D model. SOA is increased more significantly in humid and hot environments. Increases in SOA further cause an enhancement of the cooling effects of aerosols. It is crucial to consider the above processes in modeling SOA.
Meng Gao, Jinhui Gao, Bin Zhu, Rajesh Kumar, Xiao Lu, Shaojie Song, Yuzhong Zhang, Beixi Jia, Peng Wang, Gufran Beig, Jianlin Hu, Qi Ying, Hongliang Zhang, Peter Sherman, and Michael B. McElroy
Atmos. Chem. Phys., 20, 4399–4414, https://doi.org/10.5194/acp-20-4399-2020, https://doi.org/10.5194/acp-20-4399-2020, 2020
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A regional fully coupled meteorology–chemistry model, Weather Research and Forecasting model with Chemistry (WRF-Chem), was employed to study the seasonality of ozone (O3) pollution and its sources in both China and India.
Xin Yu, Melissa Venecek, Anikender Kumar, Jianlin Hu, Saffet Tanrikulu, Su-Tzai Soon, Cuong Tran, David Fairley, and Michael J. Kleeman
Atmos. Chem. Phys., 19, 14677–14702, https://doi.org/10.5194/acp-19-14677-2019, https://doi.org/10.5194/acp-19-14677-2019, 2019
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Predictions and measurements of ultrafine particle number and mass concentrations were in overall good agreement at 14 sites across California in the years 2012, 2015, and 2016. On-road vehicles, food cooking, and aircraft were important sources of ultrafine particles as expected, but natural gas combustion was also a significant source at all locations across California. These results can be used to study the health effects of ultrafine particles.
Jingwei Liu, Xin Li, Yiming Yang, Haichao Wang, Yusheng Wu, Xuewei Lu, Mindong Chen, Jianlin Hu, Xiaobo Fan, Limin Zeng, and Yuanhang Zhang
Atmos. Meas. Tech., 12, 4439–4453, https://doi.org/10.5194/amt-12-4439-2019, https://doi.org/10.5194/amt-12-4439-2019, 2019
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Incoherent broadband cavity-enhanced absorption spectroscopy (IBBCEAS) has been proven to be a reliable method for measuring glyoxal and methylglyoxal in the atmosphere. However, the commonly overlying strong spectral absorption of nitrogen dioxide hampers the accurate and sensitive resolve of the weak absorption features of glyoxal and methylglyoxal. Here, we report a custom-built IBBCEAS system that could overcome this problem by quantitatively removing nitrogen dioxide from the sample air.
Xionghui Qiu, Qi Ying, Shuxiao Wang, Lei Duan, Jian Zhao, Jia Xing, Dian Ding, Yele Sun, Baoxian Liu, Aijun Shi, Xiao Yan, Qingcheng Xu, and Jiming Hao
Atmos. Chem. Phys., 19, 6737–6747, https://doi.org/10.5194/acp-19-6737-2019, https://doi.org/10.5194/acp-19-6737-2019, 2019
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Current chemical transport models cannot capture the diurnal and nocturnal variation in atmospheric nitrate, which may be relative to the missing atmospheric chlorine chemistry. In this work, the Community Multiscale Air Quality (CMAQ) model with improved chlorine heterogeneous chemistry is applied to simulate the impact of chlorine chemistry on summer nitrate concentrations in Beijing. The results of this work can improve our understanding of nitrate formation.
Xue Qiao, Hao Guo, Ya Tang, Pengfei Wang, Wenye Deng, Xing Zhao, Jianlin Hu, Qi Ying, and Hongliang Zhang
Atmos. Chem. Phys., 19, 5791–5803, https://doi.org/10.5194/acp-19-5791-2019, https://doi.org/10.5194/acp-19-5791-2019, 2019
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A source-oriented version of the CMAQ model was used to quantify contributions from nine regions to PM2.5 and its components in the 18 cities within Sichuan Basin. Nonlocal emissions contribute 39–66 % and 25–52 % to the citywide average PM2.5 concentrations of 45–126 and 14–31 µg m3 in the winter and summer, respectively. This study demonstrates the importance of joint emission control efforts among cities within the SCB and neighboring regions to the east.
Xinghua Li, Junzan Han, Philip K. Hopke, Jingnan Hu, Qi Shu, Qing Chang, and Qi Ying
Atmos. Chem. Phys., 19, 2327–2341, https://doi.org/10.5194/acp-19-2327-2019, https://doi.org/10.5194/acp-19-2327-2019, 2019
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HULIS are widely distributed in atmospheric aerosol. Their sources are rarely studied quantitatively. Biomass burning is generally accepted as a major primary source with additional secondary material formed in the atmosphere. The present study provides direct evidence that residential coal burning is also a significant source of ambient HULIS in northern China based on source measurements, ambient sampling and analysis, and apportionment with source-oriented CMAQ modeling.
Junfeng Wang, Dantong Liu, Xinlei Ge, Yangzhou Wu, Fuzhen Shen, Mindong Chen, Jian Zhao, Conghui Xie, Qingqing Wang, Weiqi Xu, Jie Zhang, Jianlin Hu, James Allan, Rutambhara Joshi, Pingqing Fu, Hugh Coe, and Yele Sun
Atmos. Chem. Phys., 19, 447–458, https://doi.org/10.5194/acp-19-447-2019, https://doi.org/10.5194/acp-19-447-2019, 2019
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This work is part of the UK-China APHH campaign. We used a laser-only Aerodyne soot particle aerosol mass spectrometer, for the first time, to investigate the concentrations, size distributions and chemical compositions for those ambient submicron aerosol particles only with black carbon as cores. Our findings are valuable to understand the BC properties and processes in the densely populated megacities.
Zhaofeng Lv, Huan Liu, Qi Ying, Mingliang Fu, Zhihang Meng, Yue Wang, Wei Wei, Huiming Gong, and Kebin He
Atmos. Chem. Phys., 18, 15811–15824, https://doi.org/10.5194/acp-18-15811-2018, https://doi.org/10.5194/acp-18-15811-2018, 2018
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This study comprehensively analyzed the impacts of the marine transport sector to the concentrations of PM2.5 and its components in eastern China on multiple temporal and spatial scales. Furthermore, a source-oriented CMAQ was used to identify the contributions of shipping emissions from different maritime areas to the inland air quality. This work supplemented the insufficiency of multi-scale researches on the influences of the shipping sector on the inland air quality.
Hao Guo, Sri Harsha Kota, Kaiyu Chen, Shovan Kumar Sahu, Jianlin Hu, Qi Ying, Yuan Wang, and Hongliang Zhang
Atmos. Chem. Phys., 18, 15219–15229, https://doi.org/10.5194/acp-18-15219-2018, https://doi.org/10.5194/acp-18-15219-2018, 2018
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A total of 1.04 million premature mortalities and up to 2 years of life lost (YLL) per person were estimated in India in 2015 due to PM2.5. Premature mortality due to cerebrovascular disease (CEVD) was the highest (0.44 million), followed by ischaemic heart disease (IHD, 0.40 million). The residential sector was the largest contributor, followed by industry, agriculture and energy. Reducing PM2.5 concentrations would lead to a significant reduction in premature mortality and YLL.
Mingjie Kang, Pingqing Fu, Kimitaka Kawamura, Fan Yang, Hongliang Zhang, Zhengchen Zang, Hong Ren, Lujie Ren, Ye Zhao, Yele Sun, and Zifa Wang
Atmos. Chem. Phys., 18, 13947–13967, https://doi.org/10.5194/acp-18-13947-2018, https://doi.org/10.5194/acp-18-13947-2018, 2018
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Molecular characterization and spatial distribution of biogenic primary organic aerosol (POA) and secondary organic aerosol (SOA) in the marine atmosphere are not well known. Here, we analysed the organic molecular composition of marine aerosols collected during a marine cruise in the East China Sea during May–June 2014. Our results suggest that the Asian continent can be a natural emitter of biogenic POA and SOA, which can be transported to the downwind marine atmosphere.
Nan Li, Qingyang He, Jim Greenberg, Alex Guenther, Jingyi Li, Junji Cao, Jun Wang, Hong Liao, Qiyuan Wang, and Qiang Zhang
Atmos. Chem. Phys., 18, 7489–7507, https://doi.org/10.5194/acp-18-7489-2018, https://doi.org/10.5194/acp-18-7489-2018, 2018
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O3 pollution has been increasing in most Chinese cities in recent years. Our study reveals that the synergistic impact of individual source contributions to O3 formation should be considered in the formation of air pollution control strategies, especially for big cities in the vicinity of forests.
Jianlin Hu, Xun Li, Lin Huang, Qi Ying, Qiang Zhang, Bin Zhao, Shuxiao Wang, and Hongliang Zhang
Atmos. Chem. Phys., 17, 13103–13118, https://doi.org/10.5194/acp-17-13103-2017, https://doi.org/10.5194/acp-17-13103-2017, 2017
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The model performance of CMAQ with WRF using four different emission inventories in China was validated and compared to obtain the best air pollutants prediction for health effect studies of severe air pollution. The differences in performance of chemical transport model were analyzed for different months and regions in the vast part of China and ensemble predictions were firstly obtained from different inventories for health analysis with minimized errors for pollutants including PM2.5 and O3.
Chen Wang, Tiange Yuan, Stephen A. Wood, Kai-Uwe Goss, Jingyi Li, Qi Ying, and Frank Wania
Atmos. Chem. Phys., 17, 7529–7540, https://doi.org/10.5194/acp-17-7529-2017, https://doi.org/10.5194/acp-17-7529-2017, 2017
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Three property prediction methods are used to predict equilibrium partitioning coefficients for a set of 3414 compounds implicated in secondary organic aerosol formation. Partitioning from the gas phase to water is found to be much more uncertain than estimates of partitioning into the organic matter of aerosol. This uncertainty matters, as phase distribution is very different depending on which prediction method is applied.
Jianlin Hu, Shantanu Jathar, Hongliang Zhang, Qi Ying, Shu-Hua Chen, Christopher D. Cappa, and Michael J. Kleeman
Atmos. Chem. Phys., 17, 5379–5391, https://doi.org/10.5194/acp-17-5379-2017, https://doi.org/10.5194/acp-17-5379-2017, 2017
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Organic aerosol is a major constituent of ultrafine particulate matter (PM0.1). In this study, a source-oriented air quality model was used to simulate the concentrations and sources of primary and secondary organic aerosols in PM0.1 in California for a 9-year modeling period to provide useful information for epidemiological studies to further investigate the associations with health outcomes.
Jianlin Hu, Peng Wang, Qi Ying, Hongliang Zhang, Jianjun Chen, Xinlei Ge, Xinghua Li, Jingkun Jiang, Shuxiao Wang, Jie Zhang, Yu Zhao, and Yingyi Zhang
Atmos. Chem. Phys., 17, 77–92, https://doi.org/10.5194/acp-17-77-2017, https://doi.org/10.5194/acp-17-77-2017, 2017
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An annual simulation of secondary organic aerosol (SOA) concentrations in China with updated SOA formation pathways reveals that SOA can be a significant contributor to PM2.5 in major urban areas. Summer SOA is dominated by emissions from biogenic sources, while winter SOA is dominated by anthropogenic emissions such as alkanes and aromatic compounds. Reactive surface uptake of dicarbonyls throughout the year and isoprene epoxides in summer is the most important contributor.
Jianlin Hu, Jianjun Chen, Qi Ying, and Hongliang Zhang
Atmos. Chem. Phys., 16, 10333–10350, https://doi.org/10.5194/acp-16-10333-2016, https://doi.org/10.5194/acp-16-10333-2016, 2016
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A yearlong (2013) air-quality simulation was conducted to provide detailed temporal and spatial information of ozone, PM2.5 total and chemical components. The paper firstly compared the simulated air pollutants in China with country-wide public available observations for a whole year. It proves the ability of CMAQ in reproducing severe air pollution in China, shows directions that need to be improved, and benefits future source apportionment and human exposure studies.
Hsiang-He Lee, Shu-Hua Chen, Michael J. Kleeman, Hongliang Zhang, Steven P. DeNero, and David K. Joe
Atmos. Chem. Phys., 16, 8353–8374, https://doi.org/10.5194/acp-16-8353-2016, https://doi.org/10.5194/acp-16-8353-2016, 2016
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A source-oriented CCN module was implemented in a source-oriented chemistry model to study the effect of aerosol mixing state on fog formation. The fraction of aerosols activating into CCN at a supersaturation of 0.5 % in the Central Valley decreased from 94 % in the internal mixture model to 80 % in the source-oriented model. The internal mixture model predicted greater CCN activation than the source-oriented model due to artificial coating of hydrophobic particles with hygroscopic components.
J. Hu, H. Zhang, Q. Ying, S.-H. Chen, F. Vandenberghe, and M. J. Kleeman
Atmos. Chem. Phys., 15, 3445–3461, https://doi.org/10.5194/acp-15-3445-2015, https://doi.org/10.5194/acp-15-3445-2015, 2015
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Air quality model simulations have been conducted for California from 2000 to 2009 with 4km spatial resolution to provide exposure data for health effect studies. Comprehensive analysis shows that predicted concentrations for many pollutants are in agreement with measurements at monitoring stations, building confidence that the fields may be useful at times and locations where measurements are not available. Data can be downloaded for free at http://faculty.engineering.ucdavis.edu/kleeman/.
H. Zhang, S. P. DeNero, D. K. Joe, H.-H. Lee, S.-H. Chen, J. Michalakes, and M. J. Kleeman
Atmos. Chem. Phys., 14, 485–503, https://doi.org/10.5194/acp-14-485-2014, https://doi.org/10.5194/acp-14-485-2014, 2014
Related subject area
Subject: Aerosols | Research Activity: Atmospheric Modelling | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
The effect of BC on aerosol–boundary layer feedback: potential implications for urban pollution episodes
Relative importance of high-latitude local and long-range-transported dust for Arctic ice-nucleating particles and impacts on Arctic mixed-phase clouds
Technical note: Dispersion of cooking-generated aerosols from an urban street canyon
Comparison of six approaches to predicting droplet activation of surface active aerosol – Part 1: moderately surface active organics
The contribution of coral-reef-derived dimethyl sulfide to aerosol burden over the Great Barrier Reef: a modelling study
Development and application of a street-level meteorology and pollutant tracking system (S-TRACK)
How well do the CMIP6 models simulate dust aerosols?
Input-adaptive linear mixed-effects model for estimating alveolar lung-deposited surface area (LDSA) using multipollutant datasets
Simulated impacts of vertical distributions of black carbon aerosol on meteorology and PM2.5 concentrations in Beijing during severe haze events
Data assimilation of volcanic aerosol observations using FALL3D+PDAF
Simulation of the effects of low-volatility organic compounds on aerosol number concentrations in Europe
New particle formation event detection with Mask R-CNN
Contribution of traffic-originated nanoparticle emissions to regional and local aerosol levels
Reassessment of the radiocesium resuspension flux from contaminated ground surfaces in eastern Japan
Duff burning from wildfires in a moist region: different impacts on PM2.5 and ozone
Assimilating spaceborne lidar dust extinction can improve dust forecasts
Assessing the value meteorological ensembles add to dispersion modelling using hypothetical releases
Effects of oligomerization and decomposition on the nanoparticle growth: a model study
The role of anthropogenic aerosols in the anomalous cooling from 1960 to 1990 in the CMIP6 Earth system models
Constant flux layers with gravitational settling: links to aerosols, fog and deposition velocities
Combining POLDER-3 satellite observations and WRF-Chem numerical simulations to derive biomass burning aerosol properties over the southeast Atlantic region
Is the Atlantic Ocean driving the recent variability in South Asian dust?
Molecular-scale description of interfacial mass transfer in phase-separated aqueous secondary organic aerosol
Exploring the uncertainties in the aviation soot–cirrus effect
Reduced effective radiative forcing from cloud–aerosol interactions (ERFaci) with improved treatment of early aerosol growth in an Earth system model
LES study on turbulent dust deposition and its dependence on atmospheric boundary-layer stability
Hyperfine-resolution mapping of on-road vehicle emissions with comprehensive traffic monitoring and an intelligent transportation system
Less atmospheric radiative heating by dust due to the synergy of coarser size and aspherical shape
Air quality deterioration episode associated with a typhoon over the complex topographic environment in central Taiwan
Impact of modified turbulent diffusion of PM2.5 aerosol in WRF-Chem simulations in eastern China
What rainfall rates are most important to wet removal of different aerosol types?
Aerosol indirect effects in complex orography areas: a numerical study over the Great Alpine Region
A weather regime characterisation of winter biomass aerosol transport from southern Africa
15-year variability of desert dust optical depth on global and regional scales
Dipole pattern of summer ozone pollution in the east of China and its connection with climate variability
Aerosol absorption in global models from AeroCom phase III
A black carbon peak and its sources in the free troposphere of Beijing induced by cyclone lifting and transport from central China
Competing effects of aerosol reductions and circulation changes for future improvements in Beijing haze
Understanding the surface temperature response and its uncertainty to CO2, CH4, black carbon, and sulfate
Surface deposition of marine fog and its treatment in the Weather Research and Forecasting (WRF) model
Assessing the potential efficacy of marine cloud brightening for cooling Earth using a simple heuristic model
Aerosol effects on electrification and lightning discharges in a multicell thunderstorm simulated by the WRF-ELEC model
The response of the Amazon ecosystem to the photosynthetically active radiation fields: integrating impacts of biomass burning aerosol and clouds in the NASA GEOS Earth system model
“Warm cover”: precursory strong signals for haze pollution hidden in the middle troposphere
The MAPM (Mapping Air Pollution eMissions) method for inferring particulate matter emissions maps at city scale from in situ concentration measurements: description and demonstration of capability
Advances in Air Quality Research – Current and Emerging Challenges
Characteristics of surface energy balance and atmospheric circulation during hot-and-polluted episodes and their synergistic relationships with urban heat islands over the Pearl River Delta region
Influence of sea salt aerosols on the development of Mediterranean tropical-like cyclones
Quantification of uncertainties in the assessment of an atmospheric release source applied to the autumn 2017 106Ru event
Forecasting and identifying the meteorological and hydrological conditions favoring the occurrence of severe hazes in Beijing and Shanghai using deep learning
Jessica Slater, Hugh Coe, Gordon McFiggans, Juha Tonttila, and Sami Romakkaniemi
Atmos. Chem. Phys., 22, 2937–2953, https://doi.org/10.5194/acp-22-2937-2022, https://doi.org/10.5194/acp-22-2937-2022, 2022
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This paper shows the specific impact of black carbon (BC) on the aerosol–planetary boundary layer (PBL) feedback and its influence on a Beijing haze episode. Overall, this paper shows that strong temperature inversions prevent BC heating within the PBL from significantly increasing PBL height, while BC above the PBL suppresses PBL development significantly through the day. From this we suggest a method by which both locally and regionally emitted BC may impact urban pollution episodes.
Yang Shi, Xiaohong Liu, Mingxuan Wu, Xi Zhao, Ziming Ke, and Hunter Brown
Atmos. Chem. Phys., 22, 2909–2935, https://doi.org/10.5194/acp-22-2909-2022, https://doi.org/10.5194/acp-22-2909-2022, 2022
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We perform a modeling study to evaluate the contribution to Arctic dust loading and ice-nucleating particle (INP) population from high-latitude local and low-latitude dust. High-latitude dust has a large contribution in the lower troposphere, while low-latitude dust dominates the upper troposphere. The high-latitude dust INPs result in a net cooling effect on the Arctic surface by glaciating mixed-phase clouds. Our results highlight the contribution of high-latitude dust to the Arctic climate.
Shang Gao, Mona Kurppa, Chak K. Chan, and Keith Ngan
Atmos. Chem. Phys., 22, 2703–2726, https://doi.org/10.5194/acp-22-2703-2022, https://doi.org/10.5194/acp-22-2703-2022, 2022
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The contribution of cooking emissions to organic aerosols may exceed that of motor vehicles. However, little is known about how cooking-generated aerosols evolve in the outdoor environment. In this paper, we present a numerical study of the dispersion of cooking emissions. For plausible choices of the emission strength, cooking can yield much higher concentrations than traffic. This has important implications for public health and city planning.
Sampo Vepsäläinen, Silvia M. Calderón, Jussi Malila, and Nønne L. Prisle
Atmos. Chem. Phys., 22, 2669–2687, https://doi.org/10.5194/acp-22-2669-2022, https://doi.org/10.5194/acp-22-2669-2022, 2022
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Atmospheric aerosols act as seeds for cloud formation. Many aerosols contain surface active material that accumulates at the surface of growing droplets. This can affect cloud droplet activation, but the broad significance of the effect and the best way to model it are still debated. We compare predictions of six different model approaches to surface activity of organic aerosols and find significant differences between the models, especially with large fractions of organics in the dry particles.
Sonya L. Fiddes, Matthew T. Woodhouse, Steve Utembe, Robyn Schofield, Simon P. Alexander, Joel Alroe, Scott D. Chambers, Zhenyi Chen, Luke Cravigan, Erin Dunne, Ruhi S. Humphries, Graham Johnson, Melita D. Keywood, Todd P. Lane, Branka Miljevic, Yuko Omori, Alain Protat, Zoran Ristovski, Paul Selleck, Hilton B. Swan, Hiroshi Tanimoto, Jason P. Ward, and Alastair G. Williams
Atmos. Chem. Phys., 22, 2419–2445, https://doi.org/10.5194/acp-22-2419-2022, https://doi.org/10.5194/acp-22-2419-2022, 2022
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Coral reefs have been found to produce the climatically relevant chemical compound dimethyl sulfide (DMS). It has been suggested that corals can modify their environment via the production of DMS. We use an atmospheric chemistry model to test this theory at a regional scale for the first time. We find that it is unlikely that coral-reef-derived DMS has an influence over local climate, in part due to the proximity to terrestrial and anthropogenic aerosol sources.
Huan Zhang, Sunling Gong, Lei Zhang, Jingwei Ni, Jianjun He, Yaqiang Wang, Xu Wang, Lixin Shi, Jingyue Mo, Huabing Ke, and Shuhua Lu
Atmos. Chem. Phys., 22, 2221–2236, https://doi.org/10.5194/acp-22-2221-2022, https://doi.org/10.5194/acp-22-2221-2022, 2022
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This study established a multi-model simulation system for street-level circulation and pollutant tracking and applied to real building scenarios and atmospheric conditions. Results showed that for a particular site the potential contribution ratio varies with the height of the site, with a peak not at the ground but at a certain height. This work is of significance for urban planning and improvement of urban air quality.
Alcide Zhao, Claire L. Ryder, and Laura J. Wilcox
Atmos. Chem. Phys., 22, 2095–2119, https://doi.org/10.5194/acp-22-2095-2022, https://doi.org/10.5194/acp-22-2095-2022, 2022
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The CMIP6 models' simulated dust processes are getting more uncertain as models become more sophisticated. Of particular challenge are the links between dust cycles and optical properties, and we recommend more detailed output relating to dust cycles in future intercomparison projects to constrain such links. Also, models struggle to capture certain key regional dust processes such as dust accumulation along the slope of the Himalayas and dust seasonal cycles in North China and North America.
Pak Lun Fung, Martha A. Zaidan, Jarkko V. Niemi, Erkka Saukko, Hilkka Timonen, Anu Kousa, Joel Kuula, Topi Rönkkö, Ari Karppinen, Sasu Tarkoma, Markku Kulmala, Tuukka Petäjä, and Tareq Hussein
Atmos. Chem. Phys., 22, 1861–1882, https://doi.org/10.5194/acp-22-1861-2022, https://doi.org/10.5194/acp-22-1861-2022, 2022
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We developed an input-adaptive mixed-effects model, which was automatised to select the best combination of input variables, including up to three fixed effect variables and three time indictors as random effect variables. We tested the model to estimate lung-deposited surface area (LDSA), which correlates well with human health. The results show the inclusion of time indicators improved the sensitivity and the accuracy of the model so that it could serve as a network of virtual sensors.
Donglin Chen, Hong Liao, Yang Yang, Lei Chen, Delong Zhao, and Deping Ding
Atmos. Chem. Phys., 22, 1825–1844, https://doi.org/10.5194/acp-22-1825-2022, https://doi.org/10.5194/acp-22-1825-2022, 2022
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The black carbon (BC) vertical profile plays a critical role in BC–meteorology interaction, which also influences PM2.5 concentrations. More BC mass was assigned into high altitudes (above 1000 m) in the model, which resulted in a stronger cooling effect near the surface, a larger temperature inversion below 421 m, more reductions in PBLH, and a larger increase in near-surface PM2.5 in the daytime caused by the direct radiative effect of BC.
Leonardo Mingari, Arnau Folch, Andrew T. Prata, Federica Pardini, Giovanni Macedonio, and Antonio Costa
Atmos. Chem. Phys., 22, 1773–1792, https://doi.org/10.5194/acp-22-1773-2022, https://doi.org/10.5194/acp-22-1773-2022, 2022
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We present a new implementation of an ensemble-based data assimilation method to improve forecasting of volcanic aerosols. This system can be efficiently integrated into operational workflows by exploiting high-performance computing resources. We found a dramatic improvement of forecast quality when satellite retrievals are continuously assimilated. Management of volcanic risk and reduction of aviation impacts can strongly benefit from this research.
David Patoulias and Spyros N. Pandis
Atmos. Chem. Phys., 22, 1689–1706, https://doi.org/10.5194/acp-22-1689-2022, https://doi.org/10.5194/acp-22-1689-2022, 2022
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Our simulations indicate that the recently identified production and subsequent condensation effect of extremely low-volatility organic compounds have a smaller-than-expected effect on the total concentration of atmospheric particles. On the other hand, the oxidation of intermediate-volatility organic compounds leads to decreases in the ultrafine-particle concentrations. These results improve our understanding of the links between secondary organic aerosol formation and ultrafine particles.
Peifeng Su, Jorma Joutsensaari, Lubna Dada, Martha Arbayani Zaidan, Tuomo Nieminen, Xinyang Li, Yusheng Wu, Stefano Decesari, Sasu Tarkoma, Tuukka Petäjä, Markku Kulmala, and Petri Pellikka
Atmos. Chem. Phys., 22, 1293–1309, https://doi.org/10.5194/acp-22-1293-2022, https://doi.org/10.5194/acp-22-1293-2022, 2022
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We regarded the banana shapes in the surface plots as a special kind of object (similar to cats) and applied an instance segmentation technique to automatically identify the new particle formation (NPF) events (especially the strongest ones), in addition to their growth rates, start times, and end times. The automatic method generalized well on datasets collected in different sites, which is useful for long-term data series analysis and obtaining statistical properties of NPF events.
Miska Olin, David Patoulias, Heino Kuuluvainen, Jarkko V. Niemi, Topi Rönkkö, Spyros N. Pandis, Ilona Riipinen, and Miikka Dal Maso
Atmos. Chem. Phys., 22, 1131–1148, https://doi.org/10.5194/acp-22-1131-2022, https://doi.org/10.5194/acp-22-1131-2022, 2022
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An emission factor particle size distribution was determined from the measurements at an urban traffic site. It was used in updating a pre-existing emission inventory, and regional modeling was performed after the update. Emission inventories typically underestimate nanoparticle emissions due to challenges in determining them with high certainty. This update reveals that the simulated aerosol levels have previously been underestimated especially for urban areas and for sub-50 nm particles.
Mizuo Kajino, Akira Watanabe, Masahide Ishizuka, Kazuyuki Kita, Yuji Zaizen, Takeshi Kinase, Rikuya Hirai, Kakeru Konnai, Akane Saya, Kazuki Iwaoka, Yoshitaka Shiroma, Hidenao Hasegawa, Naofumi Akata, Masahiro Hosoda, Shinji Tokonami, and Yasuhito Igarashi
Atmos. Chem. Phys., 22, 783–803, https://doi.org/10.5194/acp-22-783-2022, https://doi.org/10.5194/acp-22-783-2022, 2022
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Using a numerical model and observations of surface concentration and depositions, the current study provides quantitative assessments of resuspension, transport, and deposition of radio-Cs in eastern Japan in 2013, which was once deposited to the ground surface after the Fukushima nuclear accident. The areal mean resuspension rate of radio-Cs from the ground to the air is estimated as 0.96 % per year, which is equivalent to 1–10 % of the decreasing rate of the ambient gamma dose in Fukushima.
Aoxing Zhang, Yongqiang Liu, Scott Goodrick, and Marcus D. Williams
Atmos. Chem. Phys., 22, 597–624, https://doi.org/10.5194/acp-22-597-2022, https://doi.org/10.5194/acp-22-597-2022, 2022
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Duff is decomposed forest fuel under ground. Duff burning often occurs at the smoldering phase with low intensity and long periods, which has little impact on regional air quality. However, there is increasing evidence for duff burning during flaming phases. This study simulates the air quality impacts of duff burning during flaming phases in the southeastern US using a regional air quality model. The results indicate the important contributions of such burning to regional PM2.5 concentrations.
Jerónimo Escribano, Enza Di Tomaso, Oriol Jorba, Martina Klose, Maria Gonçalves Ageitos, Francesca Macchia, Vassilis Amiridis, Holger Baars, Eleni Marinou, Emmanouil Proestakis, Claudia Urbanneck, Dietrich Althausen, Johannes Bühl, Rodanthi-Elisavet Mamouri, and Carlos Pérez García-Pando
Atmos. Chem. Phys., 22, 535–560, https://doi.org/10.5194/acp-22-535-2022, https://doi.org/10.5194/acp-22-535-2022, 2022
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We explore the benefits and consistency in adding lidar dust observations in a dust optical depth assimilation. We show that adding lidar data to a dust optical depth assimilation has valuable benefits and the dust analysis improves. We discuss the impact of the narrow satellite footprint of the lidar dust observations on the assimilation.
Susan J. Leadbetter, Andrew R. Jones, and Matthew C. Hort
Atmos. Chem. Phys., 22, 577–596, https://doi.org/10.5194/acp-22-577-2022, https://doi.org/10.5194/acp-22-577-2022, 2022
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In this study we look at the ability of meteorological ensembles (multiple realisations of the meteorological data) to provide information about the uncertainty in the dispersion model predictions. Statistical measures are used to evaluate the model predictions, and these show that on average the ensemble predictions outperform the non-ensemble predictions.
Arto Heitto, Kari Lehtinen, Tuukka Petäjä, Felipe Lopez-Hilfiker, Joel A. Thornton, Markku Kulmala, and Taina Yli-Juuti
Atmos. Chem. Phys., 22, 155–171, https://doi.org/10.5194/acp-22-155-2022, https://doi.org/10.5194/acp-22-155-2022, 2022
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For atmospheric aerosol particles to take part in cloud formation, they need to be at least a few tens of nanometers in diameter. By using a particle condensation model, we investigated how two types of chemical reactions, oligomerization and decomposition, of organic molecules inside the particle may affect the growth of secondary aerosol particles to these sizes. We show that the effect is potentially significant, which highlights the importance of increasing understanding of these processes.
Jie Zhang, Kalli Furtado, Steven T. Turnock, Jane P. Mulcahy, Laura J. Wilcox, Ben B. Booth, David Sexton, Tongwen Wu, Fang Zhang, and Qianxia Liu
Atmos. Chem. Phys., 21, 18609–18627, https://doi.org/10.5194/acp-21-18609-2021, https://doi.org/10.5194/acp-21-18609-2021, 2021
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The CMIP6 ESMs systematically underestimate TAS anomalies in the NH midlatitudes, especially from 1960 to 1990. The anomalous cooling is concurrent in time and space with anthropogenic SO2 emissions. The spurious drop in TAS is attributed to the overestimated aerosol concentrations. The aerosol forcing sensitivity cannot well explain the inter-model spread of PHC biases. And the cloud-amount term accounts for most of the inter-model spread in aerosol forcing sensitivity.
Peter A. Taylor
Atmos. Chem. Phys., 21, 18263–18269, https://doi.org/10.5194/acp-21-18263-2021, https://doi.org/10.5194/acp-21-18263-2021, 2021
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Atmospheric aerosols including fog droplets can be deposited on the ground or on water surfaces. This is due to both gravitational settling and turbulent impaction. A simple model of this combined process is developed based on conventional atmospheric-boundary-layer ideas. The model suggests an alternative formulation for the treatment of gravitational settling in the deposition velocity estimations of aerosol particles and fog droplets.
Alexandre Siméon, Fabien Waquet, Jean-Christophe Péré, Fabrice Ducos, François Thieuleux, Fanny Peers, Solène Turquety, and Isabelle Chiapello
Atmos. Chem. Phys., 21, 17775–17805, https://doi.org/10.5194/acp-21-17775-2021, https://doi.org/10.5194/acp-21-17775-2021, 2021
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For the first time, we accurately modelled the optical properties of the biomass burning aerosols (BBA) observed over the Southeast Atlantic region during their transport above clouds and over their source regions, combining a meteorology coupled with chemistry model (WRF-Chem) with innovative satellite absorbing aerosol retrievals (POLDER-3). Our results suggest a low but non-negligible brown carbon fraction (3 %) for the chemical composition of the BBA plumes observed over the source regions.
Priyanka Banerjee, Sreedharan Krishnakumari Satheesh, and Krishnaswamy Krishna Moorthy
Atmos. Chem. Phys., 21, 17665–17685, https://doi.org/10.5194/acp-21-17665-2021, https://doi.org/10.5194/acp-21-17665-2021, 2021
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We show that the Atlantic Ocean is the major driver of interannual variability in dust over South Asia since the second decade of the 21st century. This is a shift from the previously important role played by the Pacific Ocean in controlling dust over this region. Following the end of the recent global warming hiatus, anomalies of the North Atlantic sea surface temperature have remotely invoked a weakening of the South Asian monsoon and a strengthening of the dust-bearing northwesterlies.
Mária Lbadaoui-Darvas, Satoshi Takahama, and Athanasios Nenes
Atmos. Chem. Phys., 21, 17687–17714, https://doi.org/10.5194/acp-21-17687-2021, https://doi.org/10.5194/acp-21-17687-2021, 2021
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Aerosol–cloud interactions constitute the most uncertain contribution to climate change. The uptake kinetics of water by aerosol is a central process of cloud droplet formation, yet its molecular-scale mechanism is unknown. We use molecular simulations to study this process for phase-separated organic particles. Our results explain the increased cloud condensation activity of such particles and can be generalized over various compositions, thus possibly serving as a basis for future models.
Mattia Righi, Johannes Hendricks, and Christof Gerhard Beer
Atmos. Chem. Phys., 21, 17267–17289, https://doi.org/10.5194/acp-21-17267-2021, https://doi.org/10.5194/acp-21-17267-2021, 2021
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A global climate model is applied to simulate the impact of aviation soot on natural cirrus clouds. A large number of numerical experiments are performed to analyse how the quantification of the resulting climate impact is affected by known uncertainties. These concern the ability of aviation soot to nucleate ice and the role of model dynamics. Our results show that both aspects are important for the quantification of this effect and that discrepancies among different model studies still exist.
Sara Marie Blichner, Moa Kristina Sporre, and Terje Koren Berntsen
Atmos. Chem. Phys., 21, 17243–17265, https://doi.org/10.5194/acp-21-17243-2021, https://doi.org/10.5194/acp-21-17243-2021, 2021
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In this study we quantify how a new way of modeling the formation of new particles in the atmosphere affects the estimated cooling from aerosol–cloud interactions since pre-industrial times. Our improved scheme merges two common approaches to aerosol modeling: a sectional scheme for treating early growth and the pre-existing modal scheme in NorESM. We find that the cooling from aerosol–cloud interactions since pre-industrial times is reduced by 10 % when the new scheme is used.
Xin Yin, Cong Jiang, Yaping Shao, Ning Huang, and Jie Zhang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-809, https://doi.org/10.5194/acp-2021-809, 2021
Revised manuscript accepted for ACP
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We developed an improved deposition scheme by carrying out a series of numerical experiments using the large eddy simulation model with consideration of the fluctuation of instantaneous wind shear. Through the analysis of the simulation results, it is found that the improved deposition scheme can predict more accurately than the conventional deposition scheme especially under weak wind conditions and strongly convective atmospheric conditions.
Linhui Jiang, Yan Xia, Lu Wang, Xue Chen, Jianjie Ye, Tangyan Hou, Liqiang Wang, Yibo Zhang, Mengying Li, Zhen Li, Zhe Song, Yaping Jiang, Weiping Liu, Pengfei Li, Daniel Rosenfeld, John H. Seinfeld, and Shaocai Yu
Atmos. Chem. Phys., 21, 16985–17002, https://doi.org/10.5194/acp-21-16985-2021, https://doi.org/10.5194/acp-21-16985-2021, 2021
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This paper establishes a bottom-up approach to reveal a unique pattern of urban on-road vehicle emissions at a spatial resolution 1–3 orders of magnitude higher than current inventories. The results show that the hourly average on-road vehicle emissions of CO, NOx, HC, and PM2.5 are 74 kg, 40 kg, 8 kg, and 2 kg, respectively. Integrating our traffic-monitoring-based approach with urban measurements, we could address major data gaps between urban air pollutant emissions and concentrations.
Akinori Ito, Adeyemi A. Adebiyi, Yue Huang, and Jasper F. Kok
Atmos. Chem. Phys., 21, 16869–16891, https://doi.org/10.5194/acp-21-16869-2021, https://doi.org/10.5194/acp-21-16869-2021, 2021
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We improve the simulated dust properties of size-resolved dust concentration and particle shape. The improved simulation suggests much less atmospheric radiative heating near the major source regions, because of enhanced longwave warming at the surface by the synergy of coarser size and aspherical shape. Less intensified atmospheric heating could substantially modify the vertical temperature profile in Earth system models and thus has important implications for the projection of dust feedback.
Chuan-Yao Lin, Yang-Fan Sheng, Wan-Chin Chen, Charles C. K. Chou, Yi-Yun Chien, and Wen-Mei Chen
Atmos. Chem. Phys., 21, 16893–16910, https://doi.org/10.5194/acp-21-16893-2021, https://doi.org/10.5194/acp-21-16893-2021, 2021
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Taiwan and Hong Kong experience air quality deterioration as typhoons approach. However, the mechanism of the formation of poor air quality may differ and still not be well documented in Taiwan. The interaction between easterly typhoon circulation and Taiwan’s Central Mountain Range resulted in a lee side vortex formation. Simulation results indicated that the lee vortex and land–sea breeze, as well as the boundary layer development, were the key mechanisms.
Wenxing Jia and Xiaoye Zhang
Atmos. Chem. Phys., 21, 16827–16841, https://doi.org/10.5194/acp-21-16827-2021, https://doi.org/10.5194/acp-21-16827-2021, 2021
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Heavy aerosol pollution incidents have attracted much attention since 2013, but the temporal and spatial limitations of observations and the inaccuracy of simulation are a stumbling block to assessing pollution mechanisms. The correct simulation of boundary layer mixing process of pollutant is a challenge for mesoscale numerical models. We add the turbulent diffusion term of aerosol to the WRF-Chem model to prove the impact of turbulent diffusion on pollutant concentration.
Yong Wang, Wenwen Xia, and Guang J. Zhang
Atmos. Chem. Phys., 21, 16797–16816, https://doi.org/10.5194/acp-21-16797-2021, https://doi.org/10.5194/acp-21-16797-2021, 2021
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This study developed a novel approach to detect what rainfall rates climatologically are most efficient for wet removal of different aerosol types and applied it to a global climate model (GCM). Results show that light rain has disproportionate control on aerosol wet scavenging, with distinct rain rates for different aerosol sizes. The approach can be applied to other GCMs to better understand the aerosol wet scavenging by rainfall, which is important to better simulate aerosols.
Anna Napoli, Fabien Desbiolles, Antonio Parodi, and Claudia Pasquero
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-921, https://doi.org/10.5194/acp-2021-921, 2021
Revised manuscript accepted for ACP
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Aerosols are liquid or solid particles suspended in the air that can interact with radiation and clouds, modifying the meteoclimatic conditions. Using an atmospheric model, we study the climatological impact of aerosols through their effects on clouds in the Alps, a region characterised by high pollution levels in the densely populated surrounding flatlands. Results show that cloud cover, temperature, and precipitation are affected by aerosols and the response varies with elevation and season.
Marco Gaetani, Benjamin Pohl, Maria del Carmen Alvarez Castro, Cyrille Flamant, and Paola Formenti
Atmos. Chem. Phys., 21, 16575–16591, https://doi.org/10.5194/acp-21-16575-2021, https://doi.org/10.5194/acp-21-16575-2021, 2021
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During the dry austral winter, biomass fires in tropical Africa emit large amounts of smoke in the atmosphere, with large impacts on climate and air quality. The study of the relationship between atmospheric circulation and smoke transport shows that midlatitude atmospheric disturbances may deflect the smoke from tropical Africa towards southern Africa. Understanding the distribution of the smoke in the region is crucial for climate modelling and air quality monitoring.
Stavros-Andreas Logothetis, Vasileios Salamalikis, Antonis Gkikas, Stelios Kazadzis, Vassilis Amiridis, and Andreas Kazantzidis
Atmos. Chem. Phys., 21, 16499–16529, https://doi.org/10.5194/acp-21-16499-2021, https://doi.org/10.5194/acp-21-16499-2021, 2021
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This study investigates the temporal trends of dust optical depth (DOD; 550 nm) on global, regional and seasonal scales over a 15-year period (2003–2017) using the MIDAS (ModIs Dust AeroSol) dataset. The findings of this study revealed that the DOD was increased across the central Sahara and the Arabian Peninsula, with opposite trends over the eastern and western Sahara, the Thar and Gobi deserts, in the Bodélé Depression, and in the southern Mediterranean.
Xiaoqing Ma and Zhicong Yin
Atmos. Chem. Phys., 21, 16349–16361, https://doi.org/10.5194/acp-21-16349-2021, https://doi.org/10.5194/acp-21-16349-2021, 2021
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Severe ozone pollution frequently occurred in the east of China and obviously damages human health. The meteorological conditions effectively affect the variations in ozone pollution by modulating the natural emissions of ozone precursors and photochemical reactions in the atmosphere. In this study, a south–north dipole pattern of summer-mean ozone concentration in the east of China was identified, and its connections with preceding climate variability at different latitudes were also examined.
Maria Sand, Bjørn H. Samset, Gunnar Myhre, Jonas Gliß, Susanne E. Bauer, Huisheng Bian, Mian Chin, Ramiro Checa-Garcia, Paul Ginoux, Zak Kipling, Alf Kirkevåg, Harri Kokkola, Philippe Le Sager, Marianne T. Lund, Hitoshi Matsui, Twan van Noije, Dirk J. L. Olivié, Samuel Remy, Michael Schulz, Philip Stier, Camilla W. Stjern, Toshihiko Takemura, Kostas Tsigaridis, Svetlana G. Tsyro, and Duncan Watson-Parris
Atmos. Chem. Phys., 21, 15929–15947, https://doi.org/10.5194/acp-21-15929-2021, https://doi.org/10.5194/acp-21-15929-2021, 2021
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Absorption of shortwave radiation by aerosols can modify precipitation and clouds but is poorly constrained in models. A total of 15 different aerosol models from AeroCom phase III have reported total aerosol absorption, and for the first time, 11 of these models have reported in a consistent experiment the contributions to absorption from black carbon, dust, and organic aerosol. Here, we document the model diversity in aerosol absorption.
Zhenbin Wang, Bin Zhu, Hanqing Kang, Wen Lu, Shuqi Yan, Delong Zhao, Weihang Zhang, and Jinhui Gao
Atmos. Chem. Phys., 21, 15555–15567, https://doi.org/10.5194/acp-21-15555-2021, https://doi.org/10.5194/acp-21-15555-2021, 2021
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In this paper, by using WRF-Chem with a black carbon (BC) tagging technique, we investigate the formation mechanism and regional sources of a BC peak in the free troposphere observed by aircraft flights. Local sources dominated BC from the surface to about 700 m (78.5 %), while the BC peak in the free troposphere was almost entirely imported from external sources (99.8 %). Our results indicate that cyclone systems can quickly lift BC up to the free troposphere, as well as extend its lifetime.
Liang Guo, Laura J. Wilcox, Massimo Bollasina, Steven T. Turnock, Marianne T. Lund, and Lixia Zhang
Atmos. Chem. Phys., 21, 15299–15308, https://doi.org/10.5194/acp-21-15299-2021, https://doi.org/10.5194/acp-21-15299-2021, 2021
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Severe haze remains serious over Beijing despite emissions decreasing since 2008. Future haze changes in four scenarios are studied. The pattern conducive to haze weather increases with the atmospheric warming caused by the accumulation of greenhouse gases. However, the actual haze intensity, measured by either PM2.5 or optical depth, decreases with aerosol emissions. We show that only using the weather pattern index to predict the future change of Beijing haze is insufficient.
Kalle Nordling, Hannele Korhonen, Jouni Räisänen, Antti-Ilari Partanen, Bjørn H. Samset, and Joonas Merikanto
Atmos. Chem. Phys., 21, 14941–14958, https://doi.org/10.5194/acp-21-14941-2021, https://doi.org/10.5194/acp-21-14941-2021, 2021
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Understanding the temperature responses to different climate forcing agents, such as greenhouse gases and aerosols, is crucial for understanding future regional climate changes. In climate models, the regional temperature responses vary for all forcing agents, but the causes of this variability are poorly understood. For all forcing agents, the main component contributing to variance in regional surface temperature responses between the climate models is the clear-sky longwave emissivity.
Peter A. Taylor, Zheqi Chen, Li Cheng, Soudeh Afsharian, Wensong Weng, George A. Isaac, Terry W. Bullock, and Yongsheng Chen
Atmos. Chem. Phys., 21, 14687–14702, https://doi.org/10.5194/acp-21-14687-2021, https://doi.org/10.5194/acp-21-14687-2021, 2021
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In marine fog, droplets will impact the water surface, collide and coalesce. This removal process is underestimated or ignored in many fog and weather forecast models. A new atmospheric boundary layer approach is proposed and tested in a standard weather forecast model (Weather Research and Forecasting, WRF). New profile measurements through marine fog layers are suggested.
Robert Wood
Atmos. Chem. Phys., 21, 14507–14533, https://doi.org/10.5194/acp-21-14507-2021, https://doi.org/10.5194/acp-21-14507-2021, 2021
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A simple model is described to assess the potential for increasing solar reflection by augmenting the aerosol population below marine low clouds, which increases the concentration of cloud droplets. The model is used to predict global cooling from marine cloud brightening climate intervention as a function of the quantity, size, and lifetime of salt particles injected per sprayer, the number of sprayers deployed, the cloud updraft speed, and unperturbed aerosol size distribution.
Mengyu Sun, Dongxia Liu, Xiushu Qie, Edward R. Mansell, Yoav Yair, Alexandre O. Fierro, Shanfeng Yuan, Zhixiong Chen, and Dongfang Wang
Atmos. Chem. Phys., 21, 14141–14158, https://doi.org/10.5194/acp-21-14141-2021, https://doi.org/10.5194/acp-21-14141-2021, 2021
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By acting as cloud condensation nuclei (CCN), increasing aerosol loading tends to enhance lightning activity through microphysical processes. We investigated the aerosol effects on the development of a thunderstorm. A two-moment bulk microphysics scheme and bulk lightning model were coupled in the WRF Model to simulate a multicell thunderstorm. Sensitivity experiments show that the enhancement of lightning activity under polluted conditions results from an increasing ice crystal number.
Huisheng Bian, Eunjee Lee, Randal D. Koster, Donifan Barahona, Mian Chin, Peter R. Colarco, Anton Darmenov, Sarith Mahanama, Michael Manyin, Peter Norris, John Shilling, Hongbin Yu, and Fanwei Zeng
Atmos. Chem. Phys., 21, 14177–14197, https://doi.org/10.5194/acp-21-14177-2021, https://doi.org/10.5194/acp-21-14177-2021, 2021
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The study using the NASA Earth system model shows ~2.6 % increase in burning season gross primary production and ~1.5 % increase in annual net primary production across the Amazon Basin during 2010–2016 due to the change in surface downward direct and diffuse photosynthetically active radiation by biomass burning aerosols. Such an aerosol effect is strongly dependent on the presence of clouds. The cloud fraction at which aerosols switch from stimulating to inhibiting plant growth occurs at ~0.8.
Xiangde Xu, Wenyue Cai, Tianliang Zhao, Xinfa Qiu, Wenhui Zhu, Chan Sun, Peng Yan, Chunzhu Wang, and Fei Ge
Atmos. Chem. Phys., 21, 14131–14139, https://doi.org/10.5194/acp-21-14131-2021, https://doi.org/10.5194/acp-21-14131-2021, 2021
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We found that the structure of atmospheric thermodynamics in the troposphere can be regarded as a strong forewarning signal for variations of surface PM2.5 concentration in heavy air pollution.
Brian Nathan, Stefanie Kremser, Sara Mikaloff-Fletcher, Greg Bodeker, Leroy Bird, Ethan Dale, Dongqi Lin, Gustavo Olivares, and Elizabeth Somervell
Atmos. Chem. Phys., 21, 14089–14108, https://doi.org/10.5194/acp-21-14089-2021, https://doi.org/10.5194/acp-21-14089-2021, 2021
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The MAPM project showcases a method to improve estimates of PM2.5 emissions through an advanced statistical technique that is still new to the aerosol community. Using Christchurch, NZ, as a test bed, measurements from a field campaign in winter 2019 are incorporated into this new approach. An overestimation from local inventory estimates is identified. This technique may be exported to other urban areas in need.
Ranjeet S. Sokhi, Nicolas Moussiopoulos, Alexander Baklanov, John Bartzis, Isabelle Coll, Sandro Finardi, Rainer Friedrich, Camilla Geels, Tiia Grönholm, Tomas Halenka, Matthias Ketzel, Androniki Maragkidou, Volker Matthias, Jana Moldanova, Leonidas Ntziachristos, Klaus Schäfer, Peter Suppan, George Tsegas, Gregory Carmichael, Vicente Franco, Steve Hanna, Jukka-Pekka Jalkanen, Guus J. M. Velders, and Jaakko Kukkonen
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-581, https://doi.org/10.5194/acp-2021-581, 2021
Revised manuscript accepted for ACP
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This review of air quality research focuses on developments over the past decade. The article considers current and future challenges that are important from air quality research and policy perspectives and highlights emerging prominent gaps of knowledge. The review also examines, how air pollution management needs to adapt to new challenges and makes recommendations to guide the direction for future air quality research within the wider community and to provide support for policy.
Ifeanyichukwu C. Nduka, Chi-Yung Tam, Jianping Guo, and Steve Hung Lam Yim
Atmos. Chem. Phys., 21, 13443–13454, https://doi.org/10.5194/acp-21-13443-2021, https://doi.org/10.5194/acp-21-13443-2021, 2021
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This study analyzed the nature, mechanisms and drivers for hot-and-polluted episodes (HPEs) in the Pearl River Delta, China. A total of eight HPEs were identified and can be grouped into three clusters of HPEs that were respectively driven (1) by weak subsidence and convection induced by approaching tropical cyclones, (2) by calm conditions with low wind speed in the lower atmosphere and (3) by the combination of both aforementioned conditions.
Enrique Pravia-Sarabia, Juan José Gómez-Navarro, Pedro Jiménez-Guerrero, and Juan Pedro Montávez
Atmos. Chem. Phys., 21, 13353–13368, https://doi.org/10.5194/acp-21-13353-2021, https://doi.org/10.5194/acp-21-13353-2021, 2021
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Given the hazardous nature of medicanes, studies focused on understanding and quantifying the processes governing their formation have become paramount for present and future disaster risk reduction. Therefore, enhancing the modeling and forecasting capabilities of such events is of crucial importance. In this sense, the authors find that the microphysical processes, and specifically the wind--sea salt aerosol feedback, play a key role in their development and thus should not be neglected.
Joffrey Dumont Le Brazidec, Marc Bocquet, Olivier Saunier, and Yelva Roustan
Atmos. Chem. Phys., 21, 13247–13267, https://doi.org/10.5194/acp-21-13247-2021, https://doi.org/10.5194/acp-21-13247-2021, 2021
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The assessment of the environmental consequences of a radionuclide release depends on the estimation of its source. This paper aims to develop inverse Bayesian methods which combine transport models with measurements, in order to reconstruct the ensemble of possible sources.
Three methods to quantify uncertainties based on the definition of probability distributions and the physical models are proposed and evaluated for the case of 106Ru releases over Europe in 2017.
Chien Wang
Atmos. Chem. Phys., 21, 13149–13166, https://doi.org/10.5194/acp-21-13149-2021, https://doi.org/10.5194/acp-21-13149-2021, 2021
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Haze caused by abundant atmospheric aerosols has become a serious environmental issue in many countries. An innovative deep-learning machine has been developed to forecast the occurrence of hazes in two Asian megacities (Beijing and Shanghai) and has achieved good overall accuracy. Using this machine, typical regional meteorological and hydrological regimes associated with haze and non-haze events in the two cities have also been, arguably for the first time, successfully categorized.
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Short summary
Meteorological conditions play important roles in the formation of O3 and PM2.5 pollution in China. O3 is most sensitive to temperature and the sensitivity is dependent on the O3 chemistry formation or loss regime. PM2.5 is negatively sensitive to temperature, wind speed, and planetary boundary layer height and positively sensitive to humidity. The results imply that air quality in certain regions of China is sensitive to climate changes.
Meteorological conditions play important roles in the formation of O3 and PM2.5 pollution in...
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