Journal of Geophysical Research: Atmospheres最新文献

{"title":"A Regimes-Based Approach to Identifying Seasonal State-Dependent Prediction Skill","authors":"Kyle Shackelford,&nbsp;Charlotte A. DeMott,&nbsp;Peter Jan van Leeuwen,&nbsp;Elizabeth A. Barnes","doi":"10.1029/2024JD042917","DOIUrl":"https://doi.org/10.1029/2024JD042917","url":null,"abstract":"<p>Subseasonal-to-decadal atmospheric prediction skill attained from initial conditions is typically limited by the chaotic nature of the atmosphere. However, for some atmospheric phenomena, prediction skill on subseasonal-to-decadal timescales is increased when the initial conditions are in a particular state. In this study, we employ machine learning to identify sea surface temperature (SST) regimes that enhance prediction skill of North Atlantic atmospheric circulation. An ensemble of artificial neural networks is trained to predict anomalous, low-pass filtered 500 mb height at 7–8 weeks lead using SST. We then use self-organizing maps (SOMs) constructed from 9 regions within the SST domain to detect state-dependent prediction skill. SOMs are built using the entire SST time series, and we assess which SOM units feature confident neural network predictions. Four regimes are identified that provide skillful seasonal predictions of 500 mb height. Our findings demonstrate the importance of extratropical decadal SST variability in modulating downstream ENSO teleconnections to the North Atlantic. The methodology presented could aid future forecasting on subseasonal-to-decadal timescales.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 8","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JD042917","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143840923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Uncertainty Analysis of Surface Downward Longwave Radiation Models Based on Cloud Base Temperature","authors":"S. S. Yu,&nbsp;X. Z. Xin,&nbsp;H. L. Zhang,&nbsp;L. Li,&nbsp;Q. H. Liu,&nbsp;Y. Xiong","doi":"10.1029/2024JD042554","DOIUrl":"https://doi.org/10.1029/2024JD042554","url":null,"abstract":"<p>Cloud base temperature (CBT) is a crucial factor determining the surface downward longwave radiation (SDLR) under cloudy conditions. Theoretically, CBT-based parameterized models offer more accurate representations of cloud radiation effects and SDLR compared to simplistic models. However, they have poor performance in practical retrievals and have less development and application than other models. This study aims to pinpoint the shortcomings of existing CBT-based models, quantify model errors, and evaluate the impact of key parameter errors on SDLR retrieval results. Using simulated datasets based on radiative transfer models and ground-based remote sensing datasets, we conducted a detailed analysis of four CBT-based models. Our findings reveal that current model formulations inadequately capture the contributions of the atmosphere and cloud, leading to overestimation of the former and underestimation of the latter. However, these errors can partially offset each other. Under accurate parameter conditions, mean SDLR errors are within 10 W/m² for Diak, Gupta-Cal, and Wang models, and approximately −5 W/m² for the Schmetz model. The influence of cloud base height (CBH) and cloud fraction (CF) is significant and complex. When errors in CBH and CF are combined, CF error exerts a dominant influence. Surface downward longwave radiation error is insensitive to CBH error when CF is underestimated, while the impact of CBH error on SDLR estimation is notable when CF is overestimated. Regardless of CBH error, SDLR error is sensitive to CF error. Furthermore, when model errors are combined with cloud parameter errors, model errors may amplify or partially offset the impacts of parameter errors.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 8","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143840921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tibetan Plateau Uplift Changed the Asian Climate and Regulated Its Responses to Orbital Forcing During the Late Eocene to Early Miocene","authors":"Qinyao Zhang,&nbsp;Jian Zhang,&nbsp;Chao Ma,&nbsp;Zhantao Feng,&nbsp;Wenqiang Tang,&nbsp;Xiaomin Fang","doi":"10.1029/2024JD042872","DOIUrl":"https://doi.org/10.1029/2024JD042872","url":null,"abstract":"<p>The Tibetan Plateau (TP) uplift is believed to influence the Asian climate evolution on tectonic timescales throughout the Cenozoic era, whereas the orbital cycles on much shorter orbital timescales. However, the specific role of the former in modulating Asian climate responses to the latter remains inadequately understood, hindering our comprehension of the Asian climate evolution. To tackle this issue, we simulated the Asian climate by using the Community Earth System Model version 1.2.2 for two key periods: the late Eocene-early Oligocene and the late Oligocene-early Miocene. The simulations show that the TP uplift not only strengthened the Asian monsoon (AM), resulting in more annual and summer precipitation due to its elevated heating but also significantly amplified eccentricity-precession forcing and minorly weakened obliquity forcing on the Asian climate. Given a relatively lower and smaller TP during the late Eocene-early Oligocene, the northern East Asian precipitation is little influenced by eccentricity-precession cycles, in contrast to previous reconstruction records. This implied a relatively higher and/or larger TP might have existed at that time. As the TP continued to rise in the late Oligocene-early Miocene, East AM precipitation became more sensitive to rising summer insolation, with precipitation increasing in the southern region while decreasing in the northern region. These findings emphasize the significance of taking the TP uplift into account when examining the influence of orbital forcing on the Asian climate during the Cenozoic.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 8","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143840922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of the Sensitivity of Tropical Cyclogenesis to Aerosol Intervention","authors":"Thao Linh Tran,&nbsp;Jiwen Fan,&nbsp;Daniel Rosenfeld,&nbsp;Yuwei Zhang,&nbsp;Helen Cleugh,&nbsp;Andrew McC Hogg,&nbsp;Roslyn Prinsley","doi":"10.1029/2024JD041600","DOIUrl":"https://doi.org/10.1029/2024JD041600","url":null,"abstract":"<p>As risks from tropical cyclones (TCs) are fueled by climate change escalation, there is an urgent need for transformational solutions to complement traditional approaches. Seeding TCs using aerosols can be a promising method to reduce cyclone intensity, supported by theoretical understanding of the microphysical effects of aerosols on TC clouds. The ideal time to intervene effectively in TCs is likely during their initial stage, before TC wind speeds reach their peak. However, studies exploring potential aerosol effects on TC formation remain scarce. This study investigates how a TC embryo responds to the addition of aerosols of varying sizes using the Weather Research &amp; Forecasting (WRF) model coupled with a spectral-bin microphysics model. We found that aerosols of different sizes and concentrations distinctively affect the pre-TC vortex's microstructure and dynamics. Fine and ultrafine aerosols enhance the latent heat of condensation, freezing, deposition, and riming, initially intensifying the vortex. However, this results in enhancement of the cold pool, thereby reducing inflow and surface fluxes, subsequently weakening the vortex. Coarse aerosols produce the opposite effect to that of fine and ultrafine aerosols. Coarse aerosols lead to a slower initial acceleration owing to enhanced warm rain. However, the resulting weaker cold pool is insufficient to effectively reduce the strength of the vortex at the later stage. This study provides critical insights into how aerosols of varying sizes and concentrations modulate the energy cascade and impact the evolution of a TC embryo, laying the groundwork for further research on TC risk management through aerosol intervention.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 8","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JD041600","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143836113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long-Term Measurements of CO2, CH4, and Isotopic Ratios of CO2 in the Western Pacific: Trends, Variations, and Implications","authors":"Chang-Feng Ou-Yang,&nbsp;Jia-Lin Wang,&nbsp;Chia-Ching Lin,&nbsp;Chia-Yang Chiu,&nbsp;Wen-Tzu Liu,&nbsp;Xin Lan,&nbsp;Don Neff,&nbsp;John B. Miller,&nbsp;Sylvia Englund Michel,&nbsp;Bruce H. Vaughn,&nbsp;Yu-Chen Chiu,&nbsp;Jhih-Yuan Yu,&nbsp;Chun-Chu Cheng,&nbsp;Russell C. Schnell,&nbsp;James W. C. White,&nbsp;Neng-Huei Lin","doi":"10.1029/2024JD042255","DOIUrl":"https://doi.org/10.1029/2024JD042255","url":null,"abstract":"<p>Carbon dioxide (CO₂) and methane (CH₄) are major contributors to climate change, increasing radiative forcing and global warming. This study investigates temporal variations of CO₂ and CH₄ levels, along with CO₂ isotopic ratios, at two western Pacific background sites: Lulin Atmospheric Background Station (LLN, 2,862 m ASL) in central Taiwan since August 2006, representing the free troposphere, and Dongsha Island (DSI, 8 m ASL) in the South China Sea since March 2010, representing sea-level conditions. Mean growth rates of CO₂, CH₄, and <i>δ</i>¹³C-CO₂ at LLN, DSI, and Mauna Loa (MLO) were found similar over the monitoring period until March 2019, whereas <i>δ</i>¹⁸O-CO₂ showed unclear trend. Seasonal patterns at LLN and DSI reflect distinct influences from different regions. At LLN, daytime photosynthesis reduced CO₂, whereas CH₄ rose in the afternoon caused by the influences associated with upslope valley breezes. We also observed an enlarging diurnal amplitude of CH₄ with a significant large growth rate of 9.2 ppb yr⁻¹ in the afternoon, which was plausibly owing to the intensified upslope winds at LLN. Based on the measurements associated with backward trajectories during nighttime, Southeast Asian biomass burning enhanced 1.5 ppm (+0.4%) of CO₂ and 15.4 ppb (+0.8%) of CH₄ at LLN in spring. Concentration weighted trajectory identifies potential source areas along the westerlies passing through southern China and Thailand, with reduced contributions from southern Southeast Asia as a result of mixing with the air in the South China Sea.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 8","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143836115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Atmospheric Reactive Nitrogen Deposition to the Global Ocean During the 2010s: Interannual Variation and Source Attribution","authors":"Shaofei Liu,&nbsp;Yuanhong Zhao,&nbsp;Yizhen Lin,&nbsp;Jingxu Wang,&nbsp;Qiong Li,&nbsp;Youfan Chen,&nbsp;Lin Zhang","doi":"10.1029/2024JD042789","DOIUrl":"https://doi.org/10.1029/2024JD042789","url":null,"abstract":"<p>This study evaluates atmospheric reactive nitrogen deposition to the global ocean from 2010 to 2019 using the GEOS-Chem model, quantifying the contributions of key anthropogenic and natural sources and examining the impacts of emissions and meteorological changes on interannual variations (IAVs). The average global oceanic nitrogen deposition is 40.7 Tg N yr⁻¹, with 78% deposited in the open ocean. Reduced nitrogen (NH_x) and oxidized nitrogen (NO_y) contribute equally predominantly through wet deposition (62%). Of the total nitrogen deposition to oceans, 39% originates from natural emissions, 33% from fuel combustion including shipping and aviation (11%), and 22% from agricultural activities. Transportation and agriculture are the major contributors in the Northern Hemispheric mid-high latitude and Coastal biomes, whereas natural emissions are dominant in Trades and Southern Hemispheric biomes. Both wet and dry NO_y deposition decreases in the Northern Hemisphere mid-high latitudes but increases in tropical biomes, whereas NH_x shows opposing changes in wet and dry deposition. Anthropogenic emissions drive over 60% of IAVs of oceanic nitrogen deposition except for the NH_x deposition over tropical biomes. Changes in anthropogenic emissions from combustion sources not only influence NO_y deposition through nitrogen oxides (NO_x) emissions from fuel combustions but also lead to opposing trends in wet and dry NH_x deposition due to nonlinear chemistry of secondary inorganic aerosol formations. These findings highlight the need for integrated management strategies targeting multiple pollutants, including NO_x, ammonia (NH₃), and sulfur dioxide (SO₂) along with international regulations on shipping and aviation to effectively control nitrogen deposition over the ocean.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 8","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143836021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Source-Specific Mass Absorption Efficiencies of Char-EC and Soot-EC Improve Accuracy in Black Carbon Radiative Effect Estimation","authors":"Huikun Liu,&nbsp;Qiyuan Wang,&nbsp;Jie Tian,&nbsp;Jin Wang,&nbsp;Ruixia Tian,&nbsp;Yong Zhang,&nbsp;Qian Zhang,&nbsp;Yonggang Xue,&nbsp;Hongmei Xu,&nbsp;Weikang Ran,&nbsp;Hui Su,&nbsp;Yongming Han,&nbsp;Junji Cao","doi":"10.1029/2024JD043079","DOIUrl":"https://doi.org/10.1029/2024JD043079","url":null,"abstract":"<p>Optical properties of elemental carbon (EC) are critical for climate modeling due to its strong light absorption. Elemental carbon consists of char-EC and soot-EC, which differ in mass absorption efficiency (MAE). However, the MAEs of these forms remain underexplored primarily due to the limited methods available for measurement, limiting the accuracy of EC climate impact assessments and leading distortions of EC radiative effect in the temporal and spatial distribution. In this study, we derived MAEs for char-EC and soot-EC using combined modeling methods based on observational data, revealing key differences. Soot-EC generally has higher MAEs than char-EC, except from biomass burning. Meteorological factors, such as relative humidity, also influence the MAEs of char-EC and soot-EC differently. The differences in sources and aging process lead to changes in the mass concentration and MAE of char-EC and soot-EC over time. Ignoring these differences can lead to discrepancies in the radiative effect from −9.1% to 18.7%. This study underscores the importance of considering the char-EC and soot-EC in accurate EC radiative effect estimates, and implies that optimizing the management of different black carbon emission sources would mitigate global warming to varying extents due to the divergence of the char/soot emission ratio and their MAE.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 8","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143836022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of M-Components on Needle Activity in Positive Cloud-To-Ground Lightning Flashes","authors":"Bin Wu,&nbsp;Qi Qi,&nbsp;Weitao Lyu,&nbsp;Ying Ma,&nbsp;Fanchao Lyu,&nbsp;Lyuwen Chen,&nbsp;Vladimir A. Rakov,&nbsp;Yang Zhang,&nbsp;Yanfeng Fan,&nbsp;Baoyou Zhu,&nbsp;Feifan Liu","doi":"10.1029/2024JD041797","DOIUrl":"https://doi.org/10.1029/2024JD041797","url":null,"abstract":"<p>High-speed video and electric field records of two positive cloud-to-ground (+CG) flashes were used to examine the effect of M-components on needle activity after the return stroke onset. We observed enhancements of needle activity that were associated with the occurrence of M-components identified by channel luminosity enhancements both at cloud altitudes and near the ground. Full-fledged M-components enhance needle activity via injection of negative charge into the bottom of grounded channel and reversing the direction of the radial electric field at the channel core, similar to +CG return strokes. Attempted M-components, identified by channel luminosity enhancements at the cloud but not near the ground, did not enhance needle activity because of the absence of significant reflection from the ground, which causes electric field reversal at the core.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 8","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143836114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"What Drives Interannual Rainfall Variability Over Northern Australia?","authors":"Hanna Heidemann,&nbsp;Sugata Narsey,&nbsp;Josephine Brown","doi":"10.1029/2024JD043016","DOIUrl":"https://doi.org/10.1029/2024JD043016","url":null,"abstract":"<p>The interannual variability of northern Australian (NA) rainfall is caused by local processes as well as remote teleconnections, many of them being interrelated. Their influence evolves throughout the wet season, from October through April. Using a stepwise linear regression and examining individual months, we identify the key drivers for rainfall variability over northwest and northeast Australia. Our research shows that the El Niño-Southern Oscillation (ENSO), followed by local sea surface temperatures (SSTs), are the key sources of rainfall variability in October and November. More specifically, the Arafura and Coral Sea SSTs contribute to rainfall variability over northwest Australia, while the Coral Sea SSTs strongly impact on northeast Australian rainfall during these months. The combined ENSO and local SST indices explain up to 50% of variance in observed NA spring monthly mean rainfall. However, the SST influence from both seas breaks down with the onset of the Australian summer monsoon in late December, and by January, SST indices explain zero variance in rainfall. Instead, December to March rainfall variability is associated with a wind-evaporation feedback, which is particularly strong over northwest Australia. The evaporation index is the only predictor that we investigated that can explain any variance in northwest Australian rainfall in January. While the more purely monsoonal northwest of Australia is dominated by variability internal to the monsoon system, rainfall variability in the northeast retains some influence from remote climate drivers throughout the monsoon season. Further research is needed to clarify the processes and timescale involved in the wind-evaporation feedback.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 8","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JD043016","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143831188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the Fate of VOCs During the Spring 2020 COVID-19 Lockdowns in Europe: A Study Based on the AirBase Data","authors":"Alexandre Caseiro,&nbsp;Pedro Salvador,&nbsp;Erika von Schneidemesser","doi":"10.1029/2024JD042845","DOIUrl":"https://doi.org/10.1029/2024JD042845","url":null,"abstract":"<p>The rapid spread of the SARS-CoV-2 virus lead many European governments to issue stay-at-home orders for the sake of controlling its impacts on the health systems. The associated decrease in human activities and therefore emissions provided a unique opportunity for a real world laboratory for atmospheric scientists. The impact on primary emissions, that is, <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mtext>NO</mtext>\u0000 <mn>2</mn>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${text{NO}}_{2}$</annotation>\u0000 </semantics></math>, has been vastly studied but its consequences on secondary pollutants, <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>O</mi>\u0000 <mn>3</mn>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${mathrm{O}}_{3}$</annotation>\u0000 </semantics></math> and secondary organic aerosol, have been reported to a lesser degree and the understanding is more limited. One reason is the chronic imbalance in the attention dedicated to volatile organic compounds. In the present study, we report on the evolution of volatile organic compounds under lockdown conditions in Europe by analyzing the concentrations relayed to the Airbase service of the European Environmental Agency. Subsetting was performed to account for human activity and the influence of meteorology. Traffic or urban stations exhibited the most important reduction in benzene and, more substantially, toluene concentrations. Xylenes, trimethylbenzenes, and ethylbenzene also decreased under lockdown conditions, though less when the synoptic conditions were associated with slow flows. Acyclic alkenes evidenced no change or increased slightly, whereas n-alkanes increased. The evolution of the relative importance of the sources was investigated by means of diagnostic ratios (toluene to benzene and benzene to toluene to ethylbenzene) and exhibited a shift from traffic toward biomass/biofuel/coal burning, indicating a possible increase in the domestic use of solvents.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 8","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JD042845","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143831232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}