Atmospheric Chemistry and Physics最新文献

{"title":"Simulations of primary and secondary ice production during an Arctic mixed-phase cloud case from the Ny-Ålesund Aerosol Cloud Experiment (NASCENT) campaign","authors":"Britta Schäfer, Robert Oscar David, Paraskevi Georgakaki, Julie Thérèse Pasquier, Georgia Sotiropoulou, Trude Storelvmo","doi":"10.5194/acp-24-7179-2024","DOIUrl":"https://doi.org/10.5194/acp-24-7179-2024","url":null,"abstract":"Abstract. The representation of Arctic clouds and their phase distributions, i.e., the amount of ice and supercooled water, influences predictions of future Arctic warming. Therefore, it is essential that cloud phase is correctly captured by models in order to accurately predict the future Arctic climate. Ice crystal formation in clouds happens through ice nucleation (primary ice production) and ice multiplication (secondary ice production). In common weather and climate models, rime splintering is the only secondary ice production process included. In addition, prescribed number concentrations of cloud condensation nuclei or cloud droplets and ice-nucleating particles are often overestimated in Arctic environments by standard model configurations. This can lead to a misrepresentation of the phase distribution and precipitation formation in Arctic mixed-phase clouds, with important implications for the Arctic surface energy budget. During the Ny-Ålesund Aerosol Cloud Experiment (NASCENT), a holographic probe mounted on a tethered balloon took in situ measurements of number and mass concentrations of ice crystals and cloud droplets in Svalbard, Norway, during fall 2019 and spring 2020. In this study, we choose one case study from this campaign that shows evidence of strong secondary ice production and use the Weather Research and Forecasting (WRF) model to simulate it at a high vertical and spatial resolution. We test the performance of different microphysical parametrizations and apply a new state-of-the-art secondary ice parametrization. We find that agreement with observations highly depends on the prescribed cloud condensation nuclei/cloud droplet and ice-nucleating particle concentrations and requires an enhancement of secondary ice production processes. Lowering mass mixing ratio thresholds for rime splintering inside the Morrison microphysics scheme is crucial to enable secondary ice production and thereby match observations for the right reasons. In our case, rime splintering is required to initiate collisional breakup. The simulated contribution from collisional breakup is larger than that from droplet shattering. Simulating ice production correctly for the right reasons is a prerequisite for reliable simulations of Arctic mixed-phase cloud responses to future temperature or aerosol perturbations.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"26 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141444767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Why does stratospheric aerosol forcing strongly cool the warm pool?","authors":"Moritz Günther, Hauke Schmidt, Claudia Timmreck, Matthew Toohey","doi":"10.5194/acp-24-7203-2024","DOIUrl":"https://doi.org/10.5194/acp-24-7203-2024","url":null,"abstract":"Abstract. Previous research has shown that stratospheric aerosol causes only a small temperature change per unit forcing because they produce stronger cooling in the tropical Indian Ocean and the western Pacific Ocean than in the global mean. The enhanced temperature change in this so-called “warm-pool” region activates strongly negative local and remote feedbacks, which dampen the global mean temperature response. This paper addresses the question of why stratospheric aerosol forcing affects warm-pool temperatures more strongly than CO2 forcing, using idealized MPI-ESM simulations. We show that the aerosol's enhanced effective forcing at the top of the atmosphere (TOA) over the warm pool contributes to the warm-pool-intensified temperature change but is not sufficient to explain the effect. Instead, the pattern of surface effective forcing, which is substantially different from the effective forcing at the TOA, is more closely linked to the temperature pattern. Independent of surface temperature changes, the aerosol heats the tropical stratosphere, accelerating the Brewer–Dobson circulation. The intensified Brewer–Dobson circulation exports additional energy from the tropics to the extratropics, which leads to a particularly strong negative forcing at the tropical surface. These results show how forced circulation changes can affect the climate response by altering the surface forcing pattern. Furthermore, they indicate that the established approach of diagnosing effective forcing at the TOA is useful for global means, but a surface perspective on the forcing must be adopted to understand the evolution of temperature patterns.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"20 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141444762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement Report: Long-term Assessment of Primary and Secondary Organic Aerosols in Shanghai Megacity throughout China’s Clean Air Actions since 2010","authors":"Haifeng Yu, Yunhua Chang, Lin Cheng, Yusen Duan, Jianlin Hu","doi":"10.5194/egusphere-2024-1488","DOIUrl":"https://doi.org/10.5194/egusphere-2024-1488","url":null,"abstract":"<strong>Abstract.</strong> A growing body of research has demonstrated the effectiveness of China’s Air Pollution Prevention and Control Action Plan in controlling PM_2.5 pollution. However, there is a lack of long-term studies investigating the impact of these abatement policies on carbonaceous aerosols in PM_2.5, particularly secondary organic carbon (SOC). Shanghai, as China’s largest megacity and prominent industrial hub, serves as a crucial gateway to the nation’s rapid development with a population exceeding twenty million. In this study, we conducted hourly online measurements of organic carbon (OC) and elemental carbon (EC) in PM_2.5 in Shanghai from July 2010 to July 2017. The results revealed that the annual concentrations (mean ± 1 σ) of OC and EC reached their peaks in 2013 (9.5 ± 6.4 and 2.7 ± 2.6 µg m^-3 to 3.0 ± 2.3 µg m^-3 and 2.7 ± 2.1 µg m^-3). Subsequently, a consistent year-by-year decrease in both OC and EC concentrations was observed, mirroring the trend observed for PM_2.5. Primary organic carbon (POC), the primary component of OC, accounted for an average of 65.6 %, displaying similar trends to OC. This finding indicates the effectiveness of primary emission control measures. However, the concentration of secondary organic carbon (SOC) did not decrease from 2013 to 2017, remaining relatively stable within the range of 2.7 ± 2.6 µg m^-3 to 3.0 ± 2.3 µg m^-3. When considering data from previous studies in Shanghai, concentrations of SOC did not exhibit a noticeable decline until 2018, coinciding with the implementation of measures targeting volatile organic compounds (VOCs) emissions. Seasonally, with the exception of 2011, OC and EC concentrations were highest during winter, likely influenced by unfavourable meteorological conditions and long-range transport. SOC displayed no distinct seasonal fluctuations, as its formation is influenced by both photochemical reactions and meteorological conditions. POC and SOC exhibited different diurnal patterns, but neither showed a significant weekend effect, suggesting limited reduction in anthropogenic activities during weekends. Furthermore, SOC concentrations exhibited simultaneous increases in summer, particularly when O₃ concentrations exceeded 50 µg m^-3, indicating that stronger oxidation reactions contribute to higher SOC concentrations. Our findings also revealed concentration gradients of SOC dependent on wind direction (WD) and wind speed (WS), with higher concentrations typically observed for winds originating from the southwest and northwest. Potential sources from distant regions were analyzed using the potential source contribution function (PSCF), indicating that the geographical potential source area is concentrated near the middle and lower Yangtze River.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"20 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141444764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface Observation Constrained High Frequency Coal Mine Methane Emissions in Shanxi China Reveal More Emissions than Inventories, Consistency with Satellite Inversion","authors":"Fan Lu, Kai Qin, Jason Blake Cohen, Qin He, Pravash Tiwari, Wei Hu, Chang Ye, Yanan Shan, Qing Xu, Shuo Wang, Qiansi Tu","doi":"10.5194/egusphere-2024-1784","DOIUrl":"https://doi.org/10.5194/egusphere-2024-1784","url":null,"abstract":"<strong>Abstract.</strong> This work focuses on Changzhi, Shanxi China, a city and surrounding rural region with one of the highest atmospheric concentrations of methane (CH₄) world-wide (campaign-wide minimum/mean/standard deviation/max observations: 2.0, 2.9, 1.3, and 16 ppm) due to a rapid increase in the mining, production, and use of coal over the past decade. An intensive 15-day surface observation campaign of CH₄ is used to drive a new analytical, mass-conserving method to compute and attribute CH₄ emissions. Observations made in concentric circles at 1 km, 3 km, and 5 km around a high production high gas coal mine yielded emissions of 0.73, 0.28, and 0.15 ppm min^-1 respectively. Attribution used a 2-box mass conserving model to identify the known mine’s emissions from 0.042–5.3 ppm min^-1, and a previously unidentified mine’s emission from 0.22–7.9 ppm min^-1. These results demonstrate the importance of simultaneously quantifying both the spatial and temporal distribution of CH₄ to better control regional-scale CH₄ emissions. Results of the attribution are used in tandem with observations of boundary layer height to quantify policy-relevant emissions from the two coal mines as 13670±7400 kg h^-1 and 5070±2270 kg h^-1respectively. Both mines display a fat tail distribution, with respective 25^th, median, and 75^th percentile values of [870, 7500, 38700] kg h^-1 and [431, 1590, 7000] kg h^-1. These findings are demonstrated to be higher than CH₄ emissions from equivalent oil and gas operations in the USA, with one about double and the other similar to day-to-day emissions inverted over 5-years using TROPOMI over the same region.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"24 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141444753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling study of the snow darkening effect by black carbon deposition over the Arctic during the melting period","authors":"Zilu Zhang, Libo Zhou, Meigen Zhang","doi":"10.5194/egusphere-2024-1717","DOIUrl":"https://doi.org/10.5194/egusphere-2024-1717","url":null,"abstract":"&lt;strong&gt;Abstract.&lt;/strong&gt; The rapid warming of the Arctic, accompanied by glacier and sea ice melt, has significant consequences for the Earth's climate, ecosystems, and economy. Recent evidence suggests that the snow-darkening effect (SDE) induced by light-absorbing particles, such as black carbon (BC) deposition, could greatly influence rapid warming in the Arctic. However, there is still a lack of ensemble simulations using high-resolution models for investigating the impacts of the SDE resulting from BC deposition on the Arctic surface energy balance. By integrating the physically based Snow, Ice, Aerosol, and Radiation (SNICAR) model with a polar-optimized version of the Weather Research and Forecasting model (Polar-WRF), this study aimed to quantify the impacts of the SDE due to BC deposition and analyze the relationship between BC aerosol mass in snow (represented by snow depth) and snow albedo reduction. The simulation results indicate that BC deposition can directly affect the surface energy balance by decreasing snow albedo and its corresponding radiative forcing (RF). On average, BC deposition at 50 ng g&lt;sup&gt;-1&lt;/sup&gt; causes a radiative forcing (RF) of 1.6 W m&lt;sup&gt;-2&lt;/sup&gt; in off-line simulations (without surface feedbacks) and 1.4 W m&lt;sup&gt;-2&lt;/sup&gt; in on-line simulations (with surface feedbacks). The high RF caused by BC deposition reached 1–4 W m&lt;sup&gt;-2&lt;/sup&gt; and mainly occurred in Greenland, Baffin Island and East Siberia, where areas with deep snow depths and large snow densities are prevalent. The changes in snow albedo are indeed strongly linked to the mass of BC aerosols. Notably, a clear linear relationship was established between snow depth and the reduction in snow albedo, with a correlation coefficient exceeding 0.9 and an R-squared value greater than 0.85 when the snow depth is shallow. However, as snow depth increases, the impact of BC on snow albedo gradually diminishes until it reaches its maximum value when the snowpack becomes sufficiently optically thick. Regions with deep snowpack, such as Greenland, tend to exhibit greater sensitivity to BC deposition due to the higher absolute mass of BC and the longer duration of the SDE. For a given column-mean BC concentration in snow, the impacts of the SDE are approximately 25–41 % greater in deep snow-covered areas than in shallow snow-covered areas, leading to a 19–40 % increase in snowmelt. A comparison between off-line and on-line coupled simulations using Polar-WRF/Noah-MP and SNICAR has provided valuable insights into the critical mechanisms and key factors influencing changes in surface heat transfer due to the impacts of the SDE induced by BC deposition in the Arctic. It has been observed that various processes, such as snow melting and land‒atmosphere interactions, play significant roles in assessing changes in the surface energy balance caused by BC deposition. Notably, off-line simulations tend to overestimate the impacts of the SDE, sometimes by more than 50 %, due ","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"53 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141444768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Satellite quantification of methane emissions from South American countries: A high-resolution inversion of TROPOMI and GOSAT observations","authors":"Sarah E. Hancock, Daniel Jacob, Zichong Chen, Hannah Nesser, Aaron Davitt, Daniel J. Varon, Melissa P. Sulprizio, Nicholas Balasus, Lucas A. Estrada, James D. East, Elise Penn, Cynthia A. Randles, John Worden, Ilse Aben, Robert J. Parker, Joannes D. Maasakkers","doi":"10.5194/egusphere-2024-1763","DOIUrl":"https://doi.org/10.5194/egusphere-2024-1763","url":null,"abstract":"<strong>Abstract.</strong> We use 2021 TROPOMI and GOSAT satellite observations of atmospheric methane in an analytical inversion to quantify national methane emissions from South America at up to 25 km × 25 km resolution. From the inversion, we derive optimal posterior estimates of methane emissions correcting the national anthropogenic emission inventories reported by individual countries to the United Nations Framework Convention on Climate Change (UNFCCC) and taken here as prior estimates. We also evaluate two alternative wetland emission inventories (WetCHARTs and LPJ-wsl) as prior estimates. Our best posterior estimates for wetland emissions are consistent with previous inventories for the Amazon but lower for the Pantanal and higher for the Parana. Our best posterior estimate of South American anthropogenic emissions is 48 (41–56) Tg a^-1, where numbers in parentheses are the range from our inversion ensemble. This is 55 % higher than UNFCCC reports and is dominated by livestock (65 % of anthropogenic total). We find that TROPOMI and GOSAT observations can effectively optimize and separate national emissions by sector for 10 of the 13 countries and territories in the region, 7 of which account for 93 % of continental anthropogenic emissions: Brazil (19 (16–23) Tg a⁻¹), Argentina (9.2 (7.9–11) Tg a⁻¹ ), Venezuela (7.0 (5.5-9.9) Tg a⁻¹), Colombia (5.0 (4.4–6.7) Tg a⁻¹), Peru (2.4 (1.6–3.9) Tg a⁻¹), Bolivia (0.96 (0.66–1.2) Tg a⁻¹), and Paraguay (0.93 (0.88 – 1.0) Tg a⁻¹). Our estimates align with UNFCCC reports for Brazil, Bolivia, and Paraguay, but are significantly higher for other countries. Emissions in all countries are dominated by livestock (mainly enteric fermentation) except for oil/gas in Venezuela and landfills in Peru. Methane intensities from the oil/gas industry are high in Venezuela (33 %), Colombia (6.5 %) and Argentina (5.9 %). Country-average emission factors for enteric fermentation from cattle in UNFCCC reports are in the range 46–60 kg head^-1 a^-1, close to the IPCC Tier 1 estimate which is mostly based on data from Brazil. Our inversion yields cattle enteric fermentation emission factors consistent with the UNFCCC reports for Brazil and Bolivia but a factor of two higher for other countries. The discrepancy for Argentina can be corrected by using IPCC Tier 2 emission estimates accounting for high milk production.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"61 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141444769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the uncertainty of anthropogenic aromatic volatile organic compound emissions: model evaluation and sensitivity analysis","authors":"Kevin Oliveira, Marc Guevara, Oriol Jorba, Hervé Petetin, Dene Bowdalo, Carles Tena, Gilbert Montané Pinto, Franco López, Carlos Pérez García-Pando","doi":"10.5194/acp-24-7137-2024","DOIUrl":"https://doi.org/10.5194/acp-24-7137-2024","url":null,"abstract":"Abstract. Volatile organic compounds (VOCs) significantly impact air quality and atmospheric chemistry, influencing ozone formation and secondary organic aerosol production. Despite their importance, the uncertainties associated with representing VOCs in atmospheric emission inventories are considerable. This work presents a spatiotemporal assessment and evaluation of benzene, toluene, and xylene (BTX) emissions and concentrations in Spain by combining bottom-up emissions, air quality modelling techniques, and ground-based observations. The emissions produced by High-Elective Resolution Modelling Emission System (HERMESv3) were used as input to the Multiscale Online Nonhydrostatic AtmospheRe CHemistry (MONARCH) chemical transport model to simulate surface concentrations across Spain. Comparing modelled and observed levels revealed uncertainty in the anthropogenic emissions, which were further explored through sensitivity tests. The largest levels of observed benzene and xylene were found in industrial sites near coke ovens, refineries, and car manufacturing facilities, where the modelling results show large underestimations. Official emissions reported for these facilities were replaced by alternative estimates, resulting in varied improvements in the model's performance across different stations. However, uncertainties associated with industrial emission processes persist, emphasising the need for further refinement. For toluene, consistent overestimations in background stations were mainly related to uncertainties in the spatial disaggregation of emissions from industrial-use solvent activities, mainly wood paint applications. Observed benzene levels in Barcelona's urban traffic areas were 5 times larger than the ones observed in Madrid. MONARCH failed to reproduce the observed gradient between the two cities due to uncertainties arising from estimating emissions from motorcycles and mopeds, as well as from different measurement methods and the model's capacity to accurately simulate meteorological conditions. Our results are constrained by the spatial and temporal coverage of available BTX observations, posing a key challenge in evaluating the spatial distribution of modelled levels and associated emissions.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"41 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141435788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Impact of Aerosol on Cloud Water: A Heuristic Perspective","authors":"Fabian Hoffmann, Franziska Glassmeier, Graham Feingold","doi":"10.5194/egusphere-2024-1725","DOIUrl":"https://doi.org/10.5194/egusphere-2024-1725","url":null,"abstract":"<strong>Abstract.</strong> Aerosol-cloud interactions modulate the role of clouds in Earth's climate. We derive, evaluate, and apply a simple model to understand aerosol-mediated cloud water adjustments in stratocumulus based on only two prognostic equations for the integrated cloud water <em>L</em> and droplet number concentration <em>N</em>. The model is solved numerically and analytically, and agrees well with documented large-eddy simulation data and satellite retrievals. A tight relationship between adjustments at low and high <em>N</em> is found, revealing the influence of non-precipitation processes (primarily entrainment) on adjustments in precipitating clouds. Furthermore, it is shown that adjustments in non-precipitating clouds tend to be positively biased by external <em>L</em> or <em>N</em> perturbations, while adjustments in precipitating clouds are barely susceptible. By deliberately reducing the complexity of the underlying system, this study constitutes a way forward to facilitate process-level understanding of cloud water adjustments.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"43 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141435794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"AERO-MAP: A data compilation and modelling approach to understand spatial variability in fine and coarse mode aerosol composition","authors":"Natalie M. Mahowald, Longlei Li, Julius Vira, Marje Prank, Douglas S. Hamilton, Hitoshi Matsui, Ron L. Miller, Louis Lu, Ezgi Akyuz, Daphne Meidan, Peter G. Hess, Heikki Lihavainen, Christine Wiedinmyer, Jenny Hand, Maria Grazia Alaimo, Célia Alves, Andres Alastuey, Paulo Artaxo, Africa Barreto, Francisco Barraza, Silvia Becagli, Giulia Calzolai, Shankararaman Chellam, Ying Chen, Patrick Chuang, David D. Cohen, Cristina Colombi, Evangelia Diapouli, Gaetano Dongarra, Konstantinos Eleftheriadis, Johann Engelbrecht, Corinne Galy-Lacaux, Cassandra Gaston, Dario Gomez, Yenny González Ramos, Roy M. Harrison, Chris Heyes, Barak Herut, Philip Hopke, Christoph Hüglin, Maria Kanakidou, Zsofia Kertesz, Zbigniew Klimont, Katriina Kyllönen, Fabrice Lambert, Xiaohong Liu, Remi Losno, Franco Lucarelli, Willy Maenhaut, Beatrice Marticorena, Randall V. Martin, Nikolaos Mihalopoulos, Yasser Morera-Gomez, Adina Paytan, Joseph Prospero, Sergio Rodríguez, Patricia Smichowski, Daniela Varrica, Brenna Walsh, Crystal Weagle, Xi Zhao","doi":"10.5194/egusphere-2024-1617","DOIUrl":"https://doi.org/10.5194/egusphere-2024-1617","url":null,"abstract":"<strong>Abstract.</strong> Aerosol particles are an important part of the Earth system, but their concentrations are spatially and temporally heterogeneous, as well as variable in size and composition. Particles can interact with incoming solar radiation and outgoing long wave radiation, change cloud properties, affect photochemistry, impact surface air quality, change the surface albedo of snow and ice, and modulate carbon dioxide uptake by the land and ocean. High particulate matter concentrations at the surface represent an important public health hazard. There are substantial datasets describing aerosol particles in the literature or in public health databases, but they have not been compiled for easy use by the climate and air quality modelling community. Here we present a new compilation of PM_2.5and PM₁₀ aerosol observations, focusing on the spatial variability across different observational stations, including composition, and demonstrate a method for comparing the datasets to model output. Overall, most of the planet or even the land fraction does not have sufficient observations of surface concentrations, and especially particle composition to understand the current distribution of particles. Most climate models exclude 10–30 % of the aerosol particles in both PM_2.5and PM₁₀ size fractions across large swaths of the globe in their current configurations, with ammonium nitrate and agricultural dust aerosol being the most important omitted aerosol types.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"18 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141435842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microphysical characteristics of precipitation within convective overshooting over East China observed by GPM DPR and ERA5","authors":"Nan Sun, Gaopeng Lu, Yunfei Fu","doi":"10.5194/acp-24-7123-2024","DOIUrl":"https://doi.org/10.5194/acp-24-7123-2024","url":null,"abstract":"Abstract. We examine the geographical distribution and microphysical three-dimensional structure of convective overshooting over East China by matching the Global Precipitation Measurement Dual-frequency Precipitation Radar (GPM DPR) instrument with the European Centre for Medium-Range Weather Forecasts Fifth-Generation Reanalysis (ERA5). Convective overshooting mainly occurs over Northeast China (NC) and northern Middle and East China (MEC), and its frequency varies from 4×10-4 to 5.4×10-3. Radar reflectivity of convective overshooting over NC accounts for a higher proportion below the freezing level, while MEC and South China (SC) account for a higher proportion above the freezing level, indicating stronger upward motion and more ice crystal particles. The microphysical processes within convective overshooting are unique, leading to various properties of the droplets in precipitation. Droplets of convective overshooting are large but sparse, with an effective droplet radius of nearly 2.5 mm below 10 km, which is about twice that of non-overshooting precipitation. The findings of this study may have important implications for the microphysical evolution associated with convective overshooting and provide more accurate precipitation microphysical parameters as input for model simulations.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"75 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141435834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}