Atmospheric Chemistry and Physics最新文献

{"title":"Impact of host climate model on contrail cirrus effective radiative forcing estimates","authors":"Weiyu Zhang, Kwinten Van Weverberg, Cyril J. Morcrette, Wuhu Feng, Kalli Furtado, Paul R. Field, Chih-Chieh Chen, Andrew Gettelman, Piers M. Forster, Daniel R. Marsh, Alexandru Rap","doi":"10.5194/egusphere-2024-1573","DOIUrl":"https://doi.org/10.5194/egusphere-2024-1573","url":null,"abstract":"<strong>Abstract.</strong> Aviation is currently estimated to contribute ~3.5 % of the net anthropogenic effective radiative forcing (ERF) of Earth's atmosphere. The largest component of this forcing comes from contrail cirrus (also with a large associated uncertainty of ~70 %), estimated to be two times larger than the contribution from aviation CO₂ emissions. Here we implement the contrail parameterisation previously developed for the USA NCAR (National Center for Atmospheric Research) Community Atmosphere Model (CAM) in the UK Met Office Unified Model (UM). By using for the first time the same contrail parameterisation in two different host climate models, this work investigates the impact of key features of the host climate model on quantifying contrail cirrus radiative impacts. We find that differences in the background humidity (in particular ice supersaturation) in the two climate models lead to substantial differences in simulated contrail fractions, with UM values being two to three times as large as those from CAM. We also find contrasting responses in overall global cloud fraction due to air traffic, with contrails causing increases and decreases in total cloud fraction in the UM and in CAM, respectively. The different complexity of the two models’ cloud microphysics schemes (i.e. single and double-moment cloud schemes in the UM and CAM, respectively) results in significant differences in the simulated changes in cloud ice water content due to aviation. When accounting for the difference in cloud microphysics complexity, we estimate the contrail cirrus ERF of the year 2018 to be 40.8 mWm⁻² in the UM and 60.1 mWm⁻² in CAM. While these two estimates are not entirely independent, they indicate a substantial (i.e. factor of ~2) uncertainty in contrail cirrus ERF from differences in the microphysics and radiation schemes of the two host climate models. We also find a factor of 8 uncertainty in contrail cirrus ERF due to existing uncertainty in contrail cirrus optical depth. We suggest that future work on the contrail cirrus climate impact should focus on better representing the microphysical and radiative contrail characteristics in different climate models and on improved observational constraints.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"31 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141475189","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":"Pristine oceans control the uncertainty in aerosol–cloud interactions","authors":"Goutam Choudhury, Karoline Block, Mahnoosh Haghighatnasab, Johannes Quaas, Tom Goren, Matthias Tesche","doi":"10.5194/egusphere-2024-1863","DOIUrl":"https://doi.org/10.5194/egusphere-2024-1863","url":null,"abstract":"<strong>Abstract.</strong> Quantifying global cloud condensation nuclei (CCN) concentrations is crucial for reducing uncertainties in radiative forcing resulting from aerosol-cloud interactions. This study analyzes two novel, independent, open-source global CCN datasets derived from spaceborne Cloud Aerosol Lidar with Orthogonal Polarization (CALIOP) measurements and Copernicus Atmosphere Monitoring Service (CAMS) reanalysis and examines the spatio-temporal variability of CCN concentrations pertinent to liquid clouds. The results reveal consistent large-scale patterns in both CALIOP and CAMS datasets, although CALIOP values are approximately 79 % higher than those from CAMS. Comparisons with existing literature demonstrate that these datasets effectively bound the regionally observed CCN concentrations, with CALIOP typically representing the upper bound and CAMS the lower bound. Monthly and annual variations in CCN concentrations obtained from the two datasets largely agree over the Northern Hemisphere and align with previously reported variations. However, inconsistencies emerge over pristine oceans, particularly in the Southern Hemisphere, where the datasets show not only opposing seasonal changes but also contrasting annual trends. A closure study of trends in CCN and cloud droplet concentrations suggests that dust-influenced and pristine-maritime environments primarily limit our current understanding of CCN-cloud-droplet relationships. Long-term CCN observations in these regions are crucial for improving global datasets and advancing our understanding of aerosol-cloud interactions.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"692 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141475203","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":"Insights on ozone pollution control in urban areas by decoupling meteorological factors based on machine learning","authors":"Yuqing Qiu, Xin Li, Wenxuan Chai, Yi Liu, Mengdi Song, Xudong Tian, Qiaoli Zou, Wenjun Lou, Wangyao Zhang, Juan Li, Yuanhang Zhang","doi":"10.5194/egusphere-2024-1576","DOIUrl":"https://doi.org/10.5194/egusphere-2024-1576","url":null,"abstract":"<strong>Abstract.</strong> Ozone (O₃) pollution is posing significant challenges to urban air quality improvement in China. The formation of surface O₃ is intricately linked to chemical reactions which are influenced by both meteorological conditions and local emissions of precursors (i.e., NOx and VOCs). The atmospheric environment capacity decreases when meteorological conditions deteriorate, resulting in the accumulation of air pollutants. Although a series of emission reduction measures have been implemented in urban areas, the effectiveness of O₃ pollution control proves inadequate. Primarily due to adverse changes in meteorological conditions, the effects of emission reduction are masked. In this study, we integrated machine learning model, the observation-based model and the positive matrix factorization model based on four years of continuous observation data from a typical urban site. We found that transport and dispersion impact the distribution of O₃ concentration. During the warm season, positive contributions of dispersion and transport to O₃ concentration ranged from 12.9 % to 24.0 %. After meteorological normalization, the sensitivity of O₃ formation and the source apportionment of VOCs changed. The sensitivity of O₃ formation changed from the NOx-limited regime to the transition regime between VOC- and NOx-limited regimes during the O₃ pollution event. Vehicle exhaust became the primary source of VOC emissions after removing the effect of dispersion, contributing 41.8 % to VOCs during the pollution periods. On the contrary, the contribution of combustion to VOCs decreased from 33.7 % to 25.1 %. Our results provided new recommendations and insights for implementing O₃ pollution control measures and evaluating the effectiveness of emission reduction in urban areas.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"337 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141489473","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":"Characterization of biogenic volatile organic compounds and their oxidation products at a stressed pine forest close to a biogas power plant","authors":"Junwei Song, Georgios I. Gkatzelis, Ralf Tillmann, Nicolas Brüggemann, Thomas Leisner, Harald Saathoff","doi":"10.5194/egusphere-2024-1768","DOIUrl":"https://doi.org/10.5194/egusphere-2024-1768","url":null,"abstract":"<strong>Abstract.</strong> In this study, we present real-time measurements of organic aerosol (OA) and biogenic volatile organic compounds (BVOCs) at a pine forest stressed by bark beetles and previous droughts close to a biogas power plant (BPP) in western Germany during June 2020. A proton-transfer-reaction time-of-flight mass spectrometer coupled with a particle inlet (CHARON-PTR-ToF-MS) and a Vocus-PTR-ToF-MS were deployed to measure OA and BVOCs. During the entire measurement period, the average concentration of monoterpenes (2.5 ± 5.3 ppb) was higher than isoprene (0.58 ± 0.54 ppb) and sesquiterpenes (0.01 ± 0.01 ppb). The OA composition mainly consisted of semi-volatile organic compounds formed from monoterpene oxidation. Based on a wind direction analysis, BVOC data were categorized into two groups with main influence from the<strong> </strong>BPP (WD-BPP) and the forest (WD-forest), respectively. In the WD-BPP group, high concentrations of monoterpenes and sesquiterpenes were attributed to BPP emissions. In the WD-forest group, higher temperatures enhanced the biogenic emissions of isoprene, monoterpenes, and sesquiterpenes especially during daytime, exceeding their photochemical consumption. Positive matrix factorization analysis of VOCs revealed substantial contributions of gaseous organic acids from BVOC oxidation during daytime, while weakly oxidized monoterpene products dominated during nighttime. Moreover, increasing relative humidity promoted the gas-to-particle partitioning of gaseous weakly oxidized monoterpene products, leading to an increase of nighttime OA mass. This study highlights that the variations of BVOCs and their oxidation products are influenced by meteorology, local BPP emissions, and chemical transformation processes at this stressed forest.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"96 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141475288","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: Combined use of MAX-DOAS and AERONET ground-based measurements in Montevideo, Uruguay, for the detection of distant biomass burning","authors":"Matías Osorio, Alejandro Agesta, Tim Bösch, Nicolás Casaballe, Andreas Richter, Leonardo M. A. Alvarado, Erna Frins","doi":"10.5194/acp-24-7447-2024","DOIUrl":"https://doi.org/10.5194/acp-24-7447-2024","url":null,"abstract":"Abstract. Biomass burning releases large amounts of aerosols and chemical species into the atmosphere, representing a major source of air pollutants. Emissions and by-products can be transported over long distances, presenting challenges in quantification. This is mainly done using satellites, which offer global coverage and data acquisition for places that are difficult to access. In this study, ground-based observations are used to assess the abundance of trace gases and aerosols. On 24 November 2020, a significant increase in formaldehyde was observed with a Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) instrument located in Montevideo (Uruguay), and its vertical column densities reached values of 2.4×1016 molec. cm−2, more than twice the values observed during the previous days. This was accompanied by an increase in the aerosol levels measured by an AErosol RObotic NETwork (AERONET) photometer located at the same site. The aerosol optical depth (AOD) at 440 nm reached values close to 1, an order of magnitude larger than typical values in Montevideo. Our findings indicate that the increase was associated with the passage of a plume originating from distant biomass burning. This conclusion is supported by TROPOspheric Monitoring Instrument (TROPOMI) satellite observations as well as HYbrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) simulations. The profiles of the gases and aerosols retrieved from the MAX-DOAS observations are consistent with the HYSPLIT analysis, showing the passage of a plume over Montevideo on 24 November located at a height of ∼ 1.5 km. This corroborates the finding that biomass burning events occurring about 800 km north of Montevideo can affect the local atmosphere through long-distance emissions transport. This study underscores the potential of ground-based atmospheric monitoring as a tool for detection of such events. Furthermore, it demonstrates greater sensitivity compared to satellite when it comes to detection of relatively small amounts of carbonyls like glyoxal and formaldehyde.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"24 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141475290","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":"Gravity waves as a mechanism of troposphere–stratosphere–mesosphere coupling during sudden stratospheric warming","authors":"Gordana Jovanovic","doi":"10.5194/egusphere-2024-1856","DOIUrl":"https://doi.org/10.5194/egusphere-2024-1856","url":null,"abstract":"<strong>Abstract.</strong> The propagation of gravity waves (GW) and their role in the coupling of the troposphere–stratosphere–mesosphere atmospheric layers during sudden stratospheric warming (SSW) are studied. A standard set of hydrodynamic equations (HD) is used to derive the analytical dispersion equations and the GWs reflection coefficient. These equations are applied to the troposphere–stratosphere and stratosphere–mesosphere boundaries to analyze which part of the GWs spectra has the greatest chance of crossing them and affecting the dynamics of the upper atmosphere. We found that the GWreflection coefficient at the troposphere–stratosphere boundary increases significantly during SSW. This is not the case for the reflection coefficient at the stratosphere–mesosphere boundary when the reflection coefficient decreases compared to its value in the no–SSW case. The generation of GWs in the stratosphere during the SSW is responsible for the reduction of the reflection coefficient. However, these additional GW fluxes are not sufficient to compensate for the reduction of GW fluxes coming from the troposphere to the mesosphere. As a result, there is mesospheric cooling accompanied by SSW events.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"73 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141475178","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 role of naphthalene and its derivatives in the formation of secondary organic aerosol in the Yangtze River Delta region, China","authors":"Fei Ye, Jingyi Li, Yaqin Gao, Hongli Wang, Jingyu An, Cheng Huang, Song Guo, Keding Lu, Kangjia Gong, Haowen Zhang, Momei Qin, Jianlin Hu","doi":"10.5194/acp-24-7467-2024","DOIUrl":"https://doi.org/10.5194/acp-24-7467-2024","url":null,"abstract":"Abstract. Naphthalene (Nap) and its derivatives, including 1-methylnaphthalene (1-MN) and 2-methylnaphthalene (2-MN), serve as prominent intermediate volatile organic compounds (IVOCs) and contribute to the formation of secondary organic aerosol (SOA). In this study, the Community Multiscale Air Quality (CMAQ) model coupled with detailed emissions and reactions of these compounds was utilized to examine their roles in the formation of SOA and other secondary pollutants in the Yangtze River Delta (YRD) region during summer. Significant underestimations of Nap and MN concentrations (by 79 % and 85 %) were observed at the Taizhou site based on the model results using the default emissions. Constrained by the observations, anthropogenic emissions of Nap and MN in the entire region were multiplied by 5 and 7, respectively, to better capture the evolution of pollutants. The average concentration of Nap reached 25 ppt (parts per trillion) in the YRD, with Nap contributing 4.1 % and 8.1 % (up to 12.6 %) of total aromatic emissions and aromatic-derived secondary organic carbon (SOC), respectively. The concentrations of 1-MN and 2-MN were relatively low, averaging 2 and 5 ppt, respectively. Together, they accounted for only 2.4 % of the aromatic-derived SOC. The impacts of Nap and MN oxidation on ozone and radicals were insignificant at regional scales but were not negligible when considering daily fluctuations in locations with high emissions of Nap and MN. This study highlights the significant roles of Nap and MN in the formation of SOA, which may pose environmental risks and result in adverse health effects.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"18 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141475199","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":"Observations of high time-resolution and size-resolved aerosol chemical composition and microphyscis in the central Arctic: implications for climate-relevant particle properties","authors":"Benjamin Heutte, Nora Bergner, Hélène Angot, Jakob B. Pernov, Lubna Dada, Jessica A. Mirrielees, Ivo Beck, Andrea Baccarini, Matthew Boyer, Jessie M. Creamean, Kaspar R. Daellenbach, Imad El Haddad, Markus M. Frey, Silvia Henning, Tiaa Laurila, Vaios Moschos, Tuukka Petäjä, Kerri A. Pratt, Lauriane L. J. Quéléver, Matthew D. Shupe, Paul Zieger, Tuija Jokinen, Julia Schmale","doi":"10.5194/egusphere-2024-1912","DOIUrl":"https://doi.org/10.5194/egusphere-2024-1912","url":null,"abstract":"<strong>Abstract.</strong> Aerosols play a critical role in the Arctic’s radiative balance, influencing solar radiation and cloud formation based on their physicochemical properties (e.g., size, abundance, and chemical composition). Limited observations in the central Arctic leave gaps in understanding aerosol dynamics year-round, affecting model predictions of climate-relevant properties. Here, we present the first annual high-time resolution observations of submicron aerosol chemical composition in the central Arctic during the Arctic Ocean 2018 (AO2018) and the 2019–2020 Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expeditions. Seasonal variations in aerosol mass concentrations and chemical composition were found to be driven by typical Arctic seasonal regimes. Organic aerosols dominated the pristine summer, while anthropogenic sulfate prevailed in autumn and spring under Arctic haze conditions. Ammonium, which impacts aerosol acidity, was consistently less abundant, relative to sulfate, in the central Arctic compared to lower latitudes of the Arctic. Cyclonic (storm) activity was found to have a significant influence on aerosol variability by enhancing both emission from local sources and transport of remote aerosol, with locally wind-generated particles contributing up to 80 % (20 %) of the cloud condensation nuclei population in autumn (spring). While the analysis presented herein provides the current central Arctic aerosol baseline, which will serve to improve climate model predictions in the region, it also underscores the importance of integrating short-timescale processes, such as seasonal wind-driven aerosol sources from blowing snow and open leads/ocean in model simulations, especially in light of the declining mid-latitude anthropogenic emissions influence and the increasing local anthropogenic emissions.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"24 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141475247","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: Aerosol vertical profiling over the Southern Great Barrier Reef using lidar and MAX-DOAS measurements","authors":"Robert G. Ryan, Lilani Toms-Hardman, Alexander Smirnov, Daniel Harrison, Robyn Schofield","doi":"10.5194/egusphere-2024-1111","DOIUrl":"https://doi.org/10.5194/egusphere-2024-1111","url":null,"abstract":"<strong>Abstract.</strong> <span>Aerosol vertical profile measurements were made using multi-axis differential optical absorption spectroscopy (MAX-DOAS) and mini-Micropulse LiDAR (MPL) at One Tree Island in the Southern Great Barrier Reef from February to April 2023. </span><span>This is an understudied location in terms of atmospheric aerosols and chemistry but is growing in importance as multiple research streams examine the influence of aerosols on radiation over the </span><span>Great Barrier Reef</span><span>. Solar radiation management proposals require regional-scale aerosol modelling, which is evaluated against aerosol extinction and optical depth measurements, necessitating a thorough understanding of measurements of these quantities. </span><span>MPL aerosol retrieval showed extinction-to-backscatter ratios (</span><span>0.031 on average) </span><span>and depolarization ratios (0.015 on average) consistent with clean, unpolluted Southern hemispheric marine aerosol. The maximum </span><span>depolarization ratio tended to be above the layer of maximum MPL backscatter, which is attributed to dried sea-salt layers above the boundary layer. MAX-DOAS and MPL extinction profiles show aerosol layers extending beyond 2 km altitude in the middle of the day, but predominantly below 1 km at other times. We also compared aerosol optical depth measurements from integrating the MAX-DOAS and MPL extinction profiles, with observations from a hand-held Microtops sun photometer. Mean aerosol optical depth (AOD) values across the campaign compare well, being 0.083 ± 0.002 for the Microtops, 0.090 ± 0.032 for the MAX-DOAS and 0.104 ± 0.028 for the MPL. However, AOD observations at a given time, and the AOD diurnal cycle, often varied between instruments. This likely indicates strong horizontal inhomogeneity in aerosol in this environment, a factor which makes it challenging to accurately compare AOD estimates from different viewing geometries, but which is important for future aerosol modelling studies in this region to consider.</span><span></span>","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"336 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141462557","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":"Age of air from in situ trace gas measurements: Insights from a new technique","authors":"Eric A. Ray, Fred L. Moore, Hella Garny, Eric J. Hintsa, Bradley D. Hall, Geoff S. Dutton, David Nance, James W. Elkins, Steven C. Wofsy, Jasna Pittman, Bruce Daube, Bianca C. Baier, Jianghanyang Li, Colm Sweeney","doi":"10.5194/egusphere-2024-1887","DOIUrl":"https://doi.org/10.5194/egusphere-2024-1887","url":null,"abstract":"<strong>Abstract.</strong> The age of air is an important transport diagnostic that can be derived from trace gas measurements and compared to global chemistry climate model output. We describe a new technique to calculate the age of air, measuring transport times from the Earth’s surface to any location in the atmosphere based on simultaneous <em>in situ</em> measurements of multiple key long-lived trace gases. The primary benefits of this new technique include (1) optimized ages of air consistent with simultaneously measured SF₆ and CO₂, (2) age of air from the upper troposphere through the stratosphere, (3) estimates of the second moment of age spectra that have not been well constrained from measurements and (4) flexibility to be used with measurements across multiple instruments, platforms and decades. We demonstrate the technique on aircraft and balloon measurements from the 1990s, the last period of extensive stratospheric <em>in situ</em> sampling, and several recent missions from the 2020s, and compare the results with previously published and modeled values.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"59 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141462548","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}