Atmospheric Research最新文献

{"title":"Rising temperature increases the response time of LAI and GPP to meteorological drought in China","authors":"Yufei Wang ,&nbsp;Peng Sun ,&nbsp;Rui Yao ,&nbsp;Chenhao Ge","doi":"10.1016/j.atmosres.2025.107989","DOIUrl":"10.1016/j.atmosres.2025.107989","url":null,"abstract":"<div><div>The response of vegetation to drought is a crucial aspect of understanding ecosystem adaptation to climate change. Response time (RT) to drought serves as a key metric to quantify vegetation anomalies induced by drought events. However, it remains unclear from the perspective of event. Therefore, we quantified the RT of Leaf Area Index (LAI) and Gross Primary Productivity (GPP) to meteorological drought across various vegetation types and climatic zones in China. Additionally, we analyzed the spatial distribution of vegetation loss during response periods and the factors influencing RT. Our findings indicated that the primary RT of LAI and GPP to Standardized Precipitation Evapotranspiration Index (SPEI) was short-term (&lt;4 months), with LAI's longer RT concentrated in southern China. In contrast, the spatial distribution of GPP's RT largely opposed that of LAI. Grasslands exhibited notably different RT spatial distributions compared to other vegetation types. Additionally, we found LAI experiencing greater losses than GPP during response periods. For RT of both LAI and GPP, near-surface temperature (TEM) emerged as the paramount influencing factor, with RT significantly increasing with rising TEM. Secondary factors included surface solar radiation (SSRD) and Vapor Pressure Deficit (VPD), but LAI and GPP showed distinct differences in their biased dependence on SSRD and VPD respectively. Most regions displayed a significant positive correlation between RT of LAI and GPP with TEM, and a negative correlation with SSRD. The study clarifies the spatiotemporal patterns of vegetation response to drought and provides a scientific basis for water resource allocation and future drought prevention and mitigation to reduce drought's negative impact on terrestrial ecosystems.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"319 ","pages":"Article 107989"},"PeriodicalIF":4.5,"publicationDate":"2025-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143526753","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":"A machine learning network for FY-3A MERSI NIR PWV retrieval under all-weather conditions","authors":"Yunzheng Huang ,&nbsp;Bao Zhang ,&nbsp;Xiongwei Ma ,&nbsp;Wanqiang Yao ,&nbsp;Qi Zhang ,&nbsp;Yibin Yao ,&nbsp;Xiaohu Lin ,&nbsp;Qingzhi Zhao ,&nbsp;Chaoqian Xu","doi":"10.1016/j.atmosres.2025.108012","DOIUrl":"10.1016/j.atmosres.2025.108012","url":null,"abstract":"<div><div>Accurate precipitable water vapor (PWV) monitoring is critical to understanding weather systems and predicting extreme meteorological events. The Moderate Resolution Spectral Imager (MERSI) onboard the Fengyun-3A (FY-3A) satellite provides PWV products with a spatial resolution of 1 km × 1 km. However, the MERSI PWV products contain a large amount of gross errors due to the stripe noise in the raw MERSI observations. Furthermore, the accuracy of MERSI PWV is also affected by weather conditions and land cover types. To address these limitations, we first applied Gaussian spatial filtering to the MERSI observations to attenuate the stripe noise and generate de-striped observations. Then, the MNPNet (MERSI NIR PWV retrieval Net) was developed based on random forest for the first time to retrieve PWV from the combination of GNSS PWV and MERSI near-infrared (NIR) atmospheric transmittance. The new nets well considered land cover types and weather conditions, and obtained amazing accuracy. The PWV derived from 256 GNSS stations in 2017 is used as a reference to validate the MNPNet PWV. The results show that root mean square errors (RMS) of the new net are 1.95 mm for clear weather, 2.68 mm for uncertain weather, 3.07 mm for cloudy weather, and 2.85 mm for all weather, which indicates improvements of 74 %, 78 %, 87 %, and 85 % over the original FY-3A/MERSI PWV. The validation results verify that the proposed algorithm has excellent performance and can markedly improve the all-weather PWV retrieval from FY-3A/MERSI. This study is essential for improving the utilization of MERSI data, weather forecasting, and climate research.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"318 ","pages":"Article 108012"},"PeriodicalIF":4.5,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143487531","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":"Changes in large-scale circulation behind the increase in extreme heat events in the Apennines (Italy)","authors":"Vincenzo Capozzi ,&nbsp;Annalisa Di Bernardino ,&nbsp;Giorgio Budillon","doi":"10.1016/j.atmosres.2025.108013","DOIUrl":"10.1016/j.atmosres.2025.108013","url":null,"abstract":"<div><div>This study, using a dataset consisting of in-situ daily temperature records and ERA5 reanalysis data, analyses the extreme temperature events (i.e., heat waves and warm spells) occurred in the Apennine Mountains (Italy) over the period 1961–2022. The available dataset has been employed to meet the following two main goals: i) to assess the linear trends of the heat waves and warm spells in terms of number of events, duration, and severity by applying the Seasonal Kendall test; ii) to shed light, on a seasonal basis, on the synoptic climatology of such events. From the linear trend analysis, it emerged that the Apennines, as many other regions of the world, experienced an increasing trend in extreme temperature episodes. In particular, in the last 30-year reference period (1991–2020), the number of regional extreme heat events increased by 134 % in summer and 102 % in spring compared to the 1961–1990 period, while in winter and autumn the increase in warm spells is smaller (53 % and 27 %, respectively) and generally not statistically significant in terms of duration and severity. Using Principal Component Analysis and k-means clustering, several synoptic-scale patterns that can trigger extreme hot conditions in the study area are identified. In the last 30-year period, notable changes in the synoptic climatology of extreme heat events have been detected in summer, as well as in spring and autumn. Specifically, in summer the large-scale patterns characterised by a cyclonic area over the eastern North Atlantic (over the British Islands or off the coasts of Ireland) and by a ridge from North Africa to the eastern Europe provide a larger relative contribution to the total number of events. Such patterns promote the advection, over the study area, of hot subtropical air masses, mainly at mid-tropospheric levels. Summer heat waves in the Apennines are generally preceded and accompanied by negative sea surface temperature anomaly with a negative tendency in the eastern North Atlantic area.</div><div>Such results supply new insights about the links between extreme heat events in the central Mediterranean area and large-scale atmospheric types as well as useful tools to improve the predictability of heat waves and warm spells at both meteorological and climatological time scales.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"319 ","pages":"Article 108013"},"PeriodicalIF":4.5,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143534168","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":"Severe constraints on water vapor diffusion due to the shrinkage of the Aral Sea","authors":"Xueyan Qin ,&nbsp;Xiuliang Yuan ,&nbsp;Hossein Tabari ,&nbsp;Rafiq Hamdi","doi":"10.1016/j.atmosres.2025.108008","DOIUrl":"10.1016/j.atmosres.2025.108008","url":null,"abstract":"<div><div>The Aral Sea has undergone dramatic shrinkage over the past half-century, losing approximately 87 % of its water body, yet how this shrinkage affects the local climate remains unclear. In this study, the effects of the Aral Sea on lake-land breeze circulation and associated water vapor diffusion were assessed by comparing two simulations, before and after the Aral Sea's shrinkage, using the Weather Research and Forecasting (WRF)-Noah regional climate model. The results show that the WRF model performs relatively well in simulating daily maximum, minimum, and mean temperatures with coefficients of determination (R²) larger than 0.75 and root mean square error (RMSE) less than 20 %, though a neutral performance was exhibited for relative humidity and wind speed, with R² values ranging from 0.4 to 0.8, and RMSE between 20 % and 60 %. Additionally, the results indicate that water vapor diffusion is substantially inhibited in both intensity and spatial extent following the shrinkage of the Aral Sea, with a maximum reduction of nearly 300 km in horizontal moisture diffusion along the southeast edge of the Aral Sea before its shrinkage, as well as a reduction of nearly 2.5 km in vertical moisture diffusion. Our findings highlight the critical need for protective measures to conserve the Aral Sea's water resources and mitigate the potential exacerbation of the region's ecological crisis.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"318 ","pages":"Article 108008"},"PeriodicalIF":4.5,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143509592","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":"Recent decades witness a strong east-west gradient of monsoon precipitation changes over Northern India","authors":"Amita Kumari ,&nbsp;Raju Attada ,&nbsp;Jasti S. Chowdary ,&nbsp;Nimmakanti Mahendra ,&nbsp;Nagaraju Chilukoti ,&nbsp;Rama Krishna Karumuri","doi":"10.1016/j.atmosres.2025.108014","DOIUrl":"10.1016/j.atmosres.2025.108014","url":null,"abstract":"<div><div>Changing climate has substantially altered the spatio-temporal rainfall pattern, especially over the Indian subcontinent where the Indian Summer Monsoon (ISM) predominates from June to September. This study explores the changes in the rainfall variability over Northern India (NI) for the period 1981–2020 and this region exhibits topographic diversity, encompassing arid Northwestern India (NWI) due to desert conditions with minimal rainfall and the rainfall-intensive region in the Indo-Gangetic Plains (IGP). In recent decades, a dipolar rainfall pattern has been observed over NI, characterized by a significant increase (reduction) in mean as well as intense rainfall over NWI (IGP). Rainfall intensity over the IGP has decreased by 10.2 %, 7.6 %, and 12 % at the 95th, 99th, and 99.9th percentiles, respectively, while the NWI has increased by 15 % and 9 % at the 95th and 99th percentiles, with a slight 0.17 % decline at the 99.9th percentile. These changes can be attributed to an increase in the frequency of monsoon depressions by about 46 % over the Arabian Sea (AS), while the Bay of Bengal (BoB) has experienced about 32 % decrease. Moreover, increased precipitation in the NWI is characterized by enhanced moisture transport and convergence, a robust low-level jet, unstable atmospheric conditions leading to strong convection. Conversely, the IGP experiences lower moisture transport and convergence, more stable atmospheric conditions, and consequently, reduced precipitation. Furthermore, this study utilizes the Detection and Attribution Model Intercomparison Project of CMIP6 data to investigate the influence of aerosols, greenhouse gases (GHGs), and natural forcings on precipitation patterns. The results reveal a similar dipole spatial pattern of rainfall due to increased aerosol concentration, indicating the role of aerosols in shaping the ISM rainfall patterns. We further employ Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) to assess how aerosol loadings impact ISM characteristics.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"318 ","pages":"Article 108014"},"PeriodicalIF":4.5,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143509594","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":"Identifications and analyses of characteristics for sea and land Breeze circulations in the Bohai Rim Region","authors":"Jie Cao ,&nbsp;Zhifan Zhu ,&nbsp;Haishan Chen ,&nbsp;Xiaobin Qiu ,&nbsp;Haijun Zhao","doi":"10.1016/j.atmosres.2025.108011","DOIUrl":"10.1016/j.atmosres.2025.108011","url":null,"abstract":"<div><div>As the closest sea to the Capital of China, the Bohai Rim region inside the Yellow Sea over complex underlying surfaces is important to the international trade, logistics and environment. It's necessary to depict the detailed three-dimensional spatial structures and temporal evolvements of sea and land breeze (SLB) circulations over this region with complicated coastlines before interpreting their meteorological contributions to extreme weather, climate and environment events. In this study, an identification approach is developed to seize SLB circulations from high resolution datasets in the Bohai Rim region. Improvements are made to replace the wind decomposing algorithm with a newly developed one which is applicable to highly complicated flows over complex underlying surfaces. SLB events in this region of 2022 are identified from 1-km model simulation data along the C-curvature coastline which is separated into the middle, northeastern and southwestern parts. Quantified and comparative analyses are performed in the form of characteristic quantities. Firstly from the mean perspective, quantities such as frequency, duration time, intensity, height, and penetration distance are adopted to investigate the spatial features of both sea breeze circulations and land ones along the three coasts. It is found that both frequencies and intensities of sea breeze events are higher than their correspondences of land ones. Distinctions among the three coasts are evident, with SLB events along the southwestern coast presenting the highest frequency and the strongest intensity. Secondly, temporal evolvements of SLB circulations are investigated along the three coasts at their start, strongest and end stages. Vertical heights of SLB circulations increase from the start stage to the strongest one, and then decrease till the end one. The vertical motion during sea breeze events along the northeastern coast is the strongest at the start and strongest stages. Thirdly, comparative analyses of sea breeze circulations along the three coasts are carried out under onshore and offshore background winds. Under onshore winds, the middle and southwestern coasts experience stronger sea breeze events, while weaker events influence the northeastern coast in the form of smaller horizontal penetration distances and larger vertical heights.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"318 ","pages":"Article 108011"},"PeriodicalIF":4.5,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143509551","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":"Do aerosols induce the differences in low cloud frequency between eastern China and eastern United States?","authors":"Hui Xu ,&nbsp;Jianping Guo ,&nbsp;Tianmeng Chen ,&nbsp;Yinjun Wang ,&nbsp;Jianbo Deng ,&nbsp;Bing Tong","doi":"10.1016/j.atmosres.2025.107994","DOIUrl":"10.1016/j.atmosres.2025.107994","url":null,"abstract":"<div><div>Low cloud exerts significant cooling effect on climate system. Nevertheless, the occurrence frequency of low clouds (OFLC) with height and its influential mechanism remain unclear, especially at the regional scale. In this study, high-vertical-resolution radiosonde measurements during the period 2018–2019 reveal that mean OFLC in eastern China (13.5 ± 6.4 %) is 21 % less than that in eastern United States (17.0 ± 4.5 %). Coincidentally, the regional distribution of aerosol optical depth (AOD) is opposite, with the mean AOD in eastern China being 150 % larger than that in eastern United States. In the meantime, the spatial pattern of surface relative humidity (RH) is similar to OFLC, with lower RH in eastern China than in eastern United States. The impacts of AOD and RH on the OFLC are explored. Results show that higher AOD usually increases the lower-tropospheric stability (LTS) and decreases the planetary boundary layer height (PBLH), while lower RH increases the lifting condensation level (LCL) for a given air temperature. Lower PBLH and higher LCL jointly decrease the difference between PBLH and LCL, which decrease the chances for the low cloud formation, resulting in lower OFLC in eastern China. The effect of AOD on OFLC depends on the RH conditions. When RH &lt; 40 %, AOD has almost no effect on OFLC in both regions. When 40 % ≤ RH ≤ 70 %, OFLC tends to decrease as AOD increases in eastern United States, but no obvious OFLC trend exists in eastern China. While AOD exerts significantly negative roles on OFLC to different extent in the two regions when RH &gt; 70 %. As AOD increases, the OFLC in eastern United States shows a significantly decreasing tends, with the correlation coefficient (R) being −0.90 between OFLC and AOD. Similarly, in eastern China, the OFLC decreases significantly when AOD &gt; 0.4, with a R of −0.80. These results deepen our understanding of regional-scale impact mechanisms of the aerosol on low cloud's occurrence and help to reduce the uncertainties in simulating the height-resolved OFLC in predicting future climate change.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"318 ","pages":"Article 107994"},"PeriodicalIF":4.5,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143478940","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":"Three-dimensional microphysical structure of the lower positive charge region in a thunderstorm: A case study for a supercell observed using dual-polarization radars","authors":"Akihito Umehara ,&nbsp;Satoru Yoshida ,&nbsp;Syugo Hayashi ,&nbsp;Shingo Shimizu ,&nbsp;Namiko Sakurai ,&nbsp;Hiroshi Yamauchi ,&nbsp;Hanako Inoue ,&nbsp;Nobuhiro Nagumo ,&nbsp;Yukari Shusse","doi":"10.1016/j.atmosres.2025.108006","DOIUrl":"10.1016/j.atmosres.2025.108006","url":null,"abstract":"<div><div>This study examines the three-dimensional (3D) microphysical and dynamical structure of the lower positive (LP) charge region within a normal tripole charge structure in a supercell thunderstorm that occurred over the Kanto Plain on August 27, 2018. The investigation utilizes hydrometeor classification and 3D wind retrieval data from dual-polarization radars, along with charge polarity classification data from a 3D lightning mapper. Key findings reveal that water-related hydrometeors (inferred as large raindrops, water-coated graupel, and/or water-coated hail) accounted for 52 % of the LP charges. Among these, water-coated hail exhibited a propensity for LP charging approximately 40 times greater than that of other hydrometeors, whereas graupel exhibited a propensity approximately 2.5 times greater. This suggests that radar-inferred graupel is not the most suitable proxy for LP charges in this event. LP charges were distributed from the bounded weak echo region associated with updrafts to the rear convergence zone. Liquid-water-related particles were more prevalent in the updraft region, while graupel and hail were more commonly observed in the downdraft. Based on these findings, the mechanisms underlying LP charge generation were elucidated. The presence of water-related particles in specific differential phase columns accompanying the updraft suggests that the shedding process may contribute to LP charge formation. This assumption aligns with previous hypotheses, supported by laboratory experiments, proposing that the removal of negatively charged liquid water from ice surfaces results in positive charging of ice particles. By correlating polarimetric radar variables with hydrometeor types and kinematic properties on a grid-by-grid basis, this study enhances our understanding of the 3D microphysical characteristics of the LP charge region and may provide important insights into lightning monitoring via radar observations.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"319 ","pages":"Article 108006"},"PeriodicalIF":4.5,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520407","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":"Complex network analysis of extreme temperature events in the Contiguous United States","authors":"Kehinde Bosikun ,&nbsp;Tayeb Jamali ,&nbsp;Behzad Ghanbarian ,&nbsp;Jürgen Kurths","doi":"10.1016/j.atmosres.2025.107995","DOIUrl":"10.1016/j.atmosres.2025.107995","url":null,"abstract":"<div><div>Extreme temperature events (ETEs), such as recent severe heat waves, are one of the consequences of climate change and global warming. To better understand their complex behavior and forecast corresponding hydrologic dynamics, investigating their spatial and temporal patterns are essential. We, therefore, analyzed ETEs over the Contiguous United States (CONUS) for both summer and winter seasons using complex network theory. For this purpose, the daily maximum and minimum temperature data were collected from the Climate Prediction Center (CPC) database. To determine the level of similarity between two geographic nodes, we employed the event synchronization (ES) method and then constructed the network of ETEs. The constructed networks were next corrected for boundary effects. Network measures i.e., degree centrality (DC), mean geographic distance (MGD), clustering coefficient (CC), betweenness centrality (BC) and long-ranged directedness (LD) were determined to analyze complex patterns within each network. Based on the network measures, we found that the ETEs are more synchronized in winters than those in summers. In addition, the BC and LD revealed that California plays an important role in the large-scale propagation of ETEs during summers, while Texas and the eastern region of New Mexico during winters. Furthermore, the evolution of ETEs from 1979 to 2022 uncovered increasing and decreasing trends for the summer and winter seasons, respectively. We also detected teleconnections near the geographic distance of 3500 km and above over the CONUS. By applying the Louvain method, we detected different communities in the network of ETEs for the summer and winter seasons. We also investigated the effect of time lag, <span><math><msub><mi>τ</mi><mi>max</mi></msub></math></span>, in the ES method on the complex network results by varying its value from 0 to 10 days. Statistical analyses including the Kolmogorov-Smirnov and paired <em>t</em>-test demonstrated significant differences in the results.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"318 ","pages":"Article 107995"},"PeriodicalIF":4.5,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143509591","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":"Clear air turbulence over the Tibetan Plateau and its effect on ozone transport in the upper troposphere-lower stratosphere","authors":"Kun Guo ,&nbsp;Qian Huang ,&nbsp;Yao Dai ,&nbsp;Yongpeng Zhang ,&nbsp;Zijun Wang ,&nbsp;Jiaxu Du ,&nbsp;Yan Chou","doi":"10.1016/j.atmosres.2025.108005","DOIUrl":"10.1016/j.atmosres.2025.108005","url":null,"abstract":"<div><div>Serious bumps caused by clear air turbulence (CAT) pose significant safety hazards during flight. CAT is also a mechanism of the stratosphere-troposphere exchange (STE), influencing the mixing of trace gases in the upper troposphere and lower stratosphere (UTLS). The strong vertical wind shear in the upper level induced by the large topography and unique climatic conditions facilitate the formation of CAT over the Tibetan Plateau (TP). This paper utilizes ERA5 reanalysis data from 1979 to 2019 to investigate the distribution characteristics of CAT over the TP. Additionally, the effects of tropopause folds on CAT were also discussed. Finally, we compare the rate of ozone change in the UTLS between cases with folds but no CAT and those with both folds and CAT, using CAMS ozone reanalysis data from 2003 to 2019. Results indicate that the occurrence frequency of CAT over the TP is significantly higher than in surrounding areas. CAT is more frequent in winter and spring, with a significant increasing trend in winter over the past 40 years. The distribution and intensity of CAT are correlated with the subtropical westerly jet stream, occurring both above and below the jet axis, showing stronger CAT observed beneath the axis. Additionally, tropopause folds significantly enhance the frequency and intensity of CAT, especially as the depth of the fold increases. CAT intensifies STE associated with folds, leading to a reduction in stratospheric ozone and a corresponding increase in tropospheric ozone.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"318 ","pages":"Article 108005"},"PeriodicalIF":4.5,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143465409","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}