Journal of Geophysical Research: Atmospheres最新文献_第10页

The Impact of Oceanic Feedbacks on Stratosphere-Troposphere Coupling in an Idealized Model 理想模型中海洋反馈对同温层-对流层耦合的影响

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-06 DOI: 10.1029/2023JD039839

N. E. Trencham, A. Czaja, J. D. Haigh

{"title":"The Impact of Oceanic Feedbacks on Stratosphere-Troposphere Coupling in an Idealized Model","authors":"N. E. Trencham, A. Czaja, J. D. Haigh","doi":"10.1029/2023JD039839","DOIUrl":"https://doi.org/10.1029/2023JD039839","url":null,"abstract":"Stratospheric temperature perturbations (STPs) caused by for example, variations in stratospheric ozone, are an important driver of changes in tropospheric dynamics, particularly pertinent to the long-term climatic evolution of the Southern Hemisphere. However, the impact of ocean feedbacks on this interaction has not been fully examined. To study it, positive STPs were applied in three otherwise identical, idealized model configurations –atmosphere-only (A), atmosphere + slab-ocean (AS), and fully-coupled atmosphere-ocean (AO)–and the resulting atmospheric changes compared. In the AO model, changes in the tropics (extratropics) experienced a poleward-expansion (shift) and positive (negative) feedback after ∼100–200 years, whilst the AS model showed atmospheric and sea surface temperature changes that did not resemble those seen in the AO model. In the AO model, changes in tropical ocean heat content were responsible for the atmospheric changes, attributable to changes in the Ekman transport. These results indicate that full atmosphere-ocean coupling should be accounted for when studying the long-term (100+ years) tropospheric response to STPs in the Southern Hemisphere. Validation with higher-resolution and more realistic models is necessary.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152246","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}

引用次数: 0

Synoptic Circulation Forcing of Large-Scale Extreme Precipitation Events Over Southeastern China 中国东南部大尺度极端降水事件的同步环流影响

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-06 DOI: 10.1029/2024JD041396

Xinxin Wu, Xuezhi Tan, Xiaohong Chen, Zeqin Huang

{"title":"Synoptic Circulation Forcing of Large-Scale Extreme Precipitation Events Over Southeastern China","authors":"Xinxin Wu, Xuezhi Tan, Xiaohong Chen, Zeqin Huang","doi":"10.1029/2024JD041396","DOIUrl":"https://doi.org/10.1029/2024JD041396","url":null,"abstract":"Large-scale extreme precipitation (LSExP) events, characterized by widespread extent, persistence, and high intensity, can pose devastating threats to millions of people, infrastructure, and ecology in highly urbanized southeastern China. Here we explore the three-dimensional (spatial and temporal) characteristics and movements of LSExPs and their direct drivers (vertical velocity, water vapor and moisture advection) under six synoptic-scale circulation patterns in southeastern China. LSExPs are classified as low-pressure or non-low types based on circulation anomaly patterns. The low-pressure LSExPs are associated with anomalous cyclonic low-pressure systems in the mid- and lower-troposphere, occurring with main coastal precipitation, while the non-low LSExPs mainly result from cold-warm air convergence and primarily affect inland areas. Low-pressure LSExPs exhibit relatively high intensity compared to non-low types, particularly on days featuring a south-low and north-high dipole pattern, which tend to produce more localized and intense precipitation events. Non-low LSExPs show larger precipitation areas, longer durations, and greater movement distances, and thus impact wider regions, compared to low-pressure LSExPs. Single high-pressure or low-pressure systems are less likely to result in LSExPs, and LSExPs are less severe if occur, compared to other types. All LSExP types move in a direction similar to that of moisture transport, strongly influenced by extreme upward motion of moisture. Low-pressure LSExPs are more related to the upward motion of the atmosphere at 850 hPa, and they also involve extreme water vapor and moisture transport.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152250","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}

引用次数: 0

Effects of Anthropogenic Aerosols on the East Asian Winter Monsoon 人为气溶胶对东亚冬季季风的影响

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-06 DOI: 10.1029/2023JD040305

Shenglong Zhang, Jonathon S. Wright, Zengyuan Guo, Wenyu Huang, Yiran Peng

{"title":"Effects of Anthropogenic Aerosols on the East Asian Winter Monsoon","authors":"Shenglong Zhang, Jonathon S. Wright, Zengyuan Guo, Wenyu Huang, Yiran Peng","doi":"10.1029/2023JD040305","DOIUrl":"https://doi.org/10.1029/2023JD040305","url":null,"abstract":"Circulation patterns linked to the East Asian winter monsoon (EAWM) affect precipitation, surface temperature, and air quality extremes over East Asia. These circulation patterns can in turn be influenced by aerosol radiative and microphysical effects through diabatic heating and its impacts on atmospheric vorticity. Using global model simulations, we investigate the effects of anthropogenic aerosol emissions and concentration changes on the intensity and variability of the EAWM. Comparison with reanalysis products indicates that the model captures the mean state of the EAWM well. The experiments indicate that anthropogenic aerosol emissions strengthen the Siberian High but weaken the East Asian jet stream, making the land areas of East Asia colder, drier, and snowier. Aerosols reduce mean surface air temperatures by approximately <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>1.5</mn>\u0000 <mo>°</mo>\u0000 </mrow>\u0000 <annotation> $1.5{}^{circ}$</annotation>\u0000 </semantics></math>C, comparable to about half of the difference between strong and weak EAWM episodes in the control simulation. The mechanisms behind these changes are evaluated by analyzing differences in the potential vorticity budget. Anthropogenic aerosol effects on diabatic heating strengthen anomalous subsidence over southern East Asia, establishing an anticyclonic circulation anomaly that suppresses deep convection and precipitation. Aerosol effects on cloud cover and cloud longwave radiative heating weaken stability over the eastern flank of the Tibetan Plateau, intensifying upslope flow along the western side of the anticyclone. Both circulation anomalies contribute to reducing surface air temperatures through regional impacts on thermal advection and the atmospheric radiative balance.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152235","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}

引用次数: 0

Sources of Atmospheric Volatile Organic Compounds During the Salt Lake Regional Smoke, Ozone and Aerosol Study (SAMOZA) 2022 2022 年盐湖地区烟雾、臭氧和气溶胶研究（SAMOZA）期间的大气挥发性有机化合物来源

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-06 DOI: 10.1029/2024JD041640

Emily M. Cope, Damien T. Ketcherside, Lixu Jin, Lu Tan, Marc Mansfield, Colleen Jones, Seth Lyman, Dan Jaffe, Lu Hu

{"title":"Sources of Atmospheric Volatile Organic Compounds During the Salt Lake Regional Smoke, Ozone and Aerosol Study (SAMOZA) 2022","authors":"Emily M. Cope, Damien T. Ketcherside, Lixu Jin, Lu Tan, Marc Mansfield, Colleen Jones, Seth Lyman, Dan Jaffe, Lu Hu","doi":"10.1029/2024JD041640","DOIUrl":"https://doi.org/10.1029/2024JD041640","url":null,"abstract":"We present measurements of volatile organic compounds (VOCs) and other trace gases taken in Salt Lake City, Utah in August and September 2022. As part of the Salt Lake regional Smoke, Ozone and Aerosol Study (SAMOZA), 35 VOCs were measured with two methods: a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS) and 2,4-dinitrophenylhydrazine (DNPH) cartridges analyzed by high-performance liquid chromatography (HPLC). Over two months, the total measured VOCs averaged 32 ± 24 ppb (mean ± standard deviation) with the hourly maximum at 141 ppb, and the total calculated OH reactivity averaged 3.7 ± 3.0 s−1 (maximum at 20.7 s−1). Among them, methanol and ethanol were the most abundant VOCs, making up 42% of the ambient mixing ratio. Isoprene and monoterpenes contributed 25% of the OH reactivity from VOCs, while formaldehyde and acetaldehyde made up another 30%. The positive matrix factorization analysis showed 5 major sources of VOCs, with 32% of abundance being attributed to secondary production/biogenic sources, 44% from the combination of traffic and personal care products, 15% from industrial solvent use, and the rest from biomass burning (10%). Moderate smoke-impacted days elevated various hazardous air pollutants (HAPs) on average by 45%–217% compared to smoke-free days. The ratio of OH reactivity from NOx to that from VOCs showed that ozone production was mostly VOC-limited throughout the campaign, consistent with our modeling study. VOCs and NOx both showed increased OH reactivity due to smoke influence. NOx featured increased reactivity on weekdays compared to weekends, an effect not shown for VOC reactivity during SAMOZA.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152249","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}

引用次数: 0

Deciphering the Significant Role of Biological Ice Nucleators in Precipitation at the Organic Molecular Level 从有机分子层面解读生物冰核在降水中的重要作用

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-06 DOI: 10.1029/2024JD041278

Mutong Niu, Wei Hu, Shu Huang, Jie Chen, Shujun Zhong, Ziye Huang, Peimin Duan, Xiangyu Pei, Jing Duan, Kai Bi, Shuang Chen, Rui Jin, Ming Sheng, Ning Yang, Libin Wu, Junjun Deng, Jialei Zhu, Fangxia Shen, Zhijun Wu, Daizhou Zhang, Pingqing Fu

{"title":"Deciphering the Significant Role of Biological Ice Nucleators in Precipitation at the Organic Molecular Level","authors":"Mutong Niu, Wei Hu, Shu Huang, Jie Chen, Shujun Zhong, Ziye Huang, Peimin Duan, Xiangyu Pei, Jing Duan, Kai Bi, Shuang Chen, Rui Jin, Ming Sheng, Ning Yang, Libin Wu, Junjun Deng, Jialei Zhu, Fangxia Shen, Zhijun Wu, Daizhou Zhang, Pingqing Fu","doi":"10.1029/2024JD041278","DOIUrl":"https://doi.org/10.1029/2024JD041278","url":null,"abstract":"Biological particles, as a fraction of organic particles, potentially play a crucial role in ice nucleation processes. However, the contributions and relationships of biological components and organic matter (OM) to atmospheric ice nucleation remain largely unexplored. Here, total ice nucleating particles (INPs), heat-resistant INPs, lysozyme-resistant INPs, nanoscale INPs (<0.22 μm), and heat-resistant nanoscale INPs in precipitation collected at the summit of Mt. Lu, China, were determined using droplet freezing assays coupled with corresponding pretreatments. Heat-sensitive INPs and lysozyme-sensitive INPs were considered as biological INPs and bacterial INPs, respectively. Microorganisms and OM molecules in precipitation were identified by high-throughput sequencing technology and ultrahigh-resolution mass spectrometry, respectively. Results revealed a predominant biological (heat-sensitive) composition (78.8% and 93.2%) of total and nanoscale INPs at temperatures above −15°C. Specifically, bacterial (lysozyme-sensitive) INPs accounted for 36.1% of the biological INPs at temperatures above −15°C. A notable correlation between sulfur-containing organic compounds, mainly proteinaceous and lignin-like substances, and INPs was uncovered, with a co-occurrence network linking these compounds to Gram-positive bacteria and Agaricomycetes. This study underscored the possible significance of sulfur-containing organic compounds in the ice nucleation capacity of biological INPs, further shedding light on the ice nucleation mechanisms and potential sources of biological INPs.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152237","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}

引用次数: 0

Contribution of Western Arabian Sea Tropical Cyclones to Rainfall in the Horn of Africa and Southern Arabian Peninsula 西阿拉伯海热带气旋对非洲之角和阿拉伯半岛南部降雨量的贡献

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-05 DOI: 10.1029/2024JD041109

P. Camberlin, O. Assowe Dabar, B. Pohl, M. Mohamed Waberi, K. Hoarau, O. Planchon

{"title":"Contribution of Western Arabian Sea Tropical Cyclones to Rainfall in the Horn of Africa and Southern Arabian Peninsula","authors":"P. Camberlin, O. Assowe Dabar, B. Pohl, M. Mohamed Waberi, K. Hoarau, O. Planchon","doi":"10.1029/2024JD041109","DOIUrl":"https://doi.org/10.1029/2024JD041109","url":null,"abstract":"The occurrence of tropical cyclones (TCs) in the Horn of Africa and nearby areas is for the first time examined to document their contribution to local rainfall and their trends over the period 1990–2020. An average 1.5 TC (of any intensity) per year was observed over the Western Arabian Sea, with two asymmetrical seasons, namely May–June (30% of cyclonic days) and September–December (70%). Case studies reveal that in many instances, TC-related rainfall extends beyond 500 km from the TC center, and that substantial rains occur one to 2 days after the lifecycle of the TC. Despite their rarity, in the otherwise arid to semi-arid context characteristic of the region, TCs contribute in both seasons to a very high percentage of total rainfall (up to 30%–60%) over the northwestern Arabian Sea, the Gulf of Aden and their coastlines. Over inland northern Somalia, contributions are much lower. TCs disproportionately contribute to some of the most intense daily falls, which are often higher than the mean annual rainfall. A strong increase in the number of TCs is found from 1990 to 2020, hence their enhanced contribution to local rainfall. This increase is associated with a warmer eastern/southern Arabian Sea, a decrease in vertical wind shear, and a strong increase in tropospheric moisture content.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JD041109","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152228","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}

引用次数: 0

Moisture and Aerosols as Key Drivers of the Turbulent State of Arctic Mixed-Phase Clouds During Idealized Moist Intrusions 湿度和气溶胶是理想化湿气入侵期间北极混相云湍流状态的关键驱动因素

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-05 DOI: 10.1029/2023JD039580

Antonios Dimitrelos, Annica M. L. Ekman, Rodrigo Caballero

{"title":"Moisture and Aerosols as Key Drivers of the Turbulent State of Arctic Mixed-Phase Clouds During Idealized Moist Intrusions","authors":"Antonios Dimitrelos, Annica M. L. Ekman, Rodrigo Caballero","doi":"10.1029/2023JD039580","DOIUrl":"https://doi.org/10.1029/2023JD039580","url":null,"abstract":"Previous studies have shown that low-level mixed-phase clouds that form during idealized moist intrusions into the Arctic can exist in either a stable (stratus) or a convective (stratocumulus) state. Here, we examine the conditions that promote a transition from the stable to the convective state through idealized simulations using a three-dimensional large-eddy simulation model coupled with a one-dimensional multilayer sea ice model. We find that the vertical distribution of the initial dew point temperature (Td) profile fundamentally influences whether a transition between the two states occurs or not. If the initial moisture content of the advected airmass decreases rapidly with height, then a turbulent transition is likely to occur and a stratocumulus cloud can form. However, the availability and properties of aerosols as well as the cloud ice content can delay or even prevent stratocumulus formation, regardless if the conditions in terms of the initial Td profile are favorable. A low cloud ice water content promotes a stably stratified cloud layer and delays the transition. Furthermore, if no cloud condensation nuclei are available at the base of the cloud when a cloud-layer instability forms, then there is no new droplet formation, the buoyancy remains low and the cloud remains as a stratus. Our results suggest that the low-level mixed-phase cloud evolution and the thermodynamic transition of an airmass during a moist intrusion into the Arctic are closely linked to the aerosol processing by the cloud, that is, a chemical transformation, and that the two processes should be considered simultaneously.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JD039580","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152205","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}

引用次数: 0

Role of Clouds in the Urban Heat Island and Extreme Heat: Houston-Galveston Metropolitan Area Case 云在城市热岛和极端高温中的作用：休斯顿-加尔维斯顿大都市区案例

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-05 DOI: 10.1029/2024JD041243

John F. Mejia, Juan Jose Henao, Ebrahim Eslami

{"title":"Role of Clouds in the Urban Heat Island and Extreme Heat: Houston-Galveston Metropolitan Area Case","authors":"John F. Mejia, Juan Jose Henao, Ebrahim Eslami","doi":"10.1029/2024JD041243","DOIUrl":"https://doi.org/10.1029/2024JD041243","url":null,"abstract":"This study examines the influence of shallow cumulus clouds on the excessive summertime heat in the Houston-Galveston metropolitan area, a coastal urban area in the warm Southeast United States. Specifically, it aims to improve our understanding of how both the clouds and the relatively cool, moist afternoon sea breeze impact the Urban Heat Island (UHI) and Heat Index (HI). During the warm season, the afternoon sea breeze phenomenon in this coastal city acts as a natural air conditioner for city residents, facilitating the dispersion of moisture, heat, and pollutants. To investigate the relationship among urbanization, clouds, and land-sea interactions, we conducted cloud- and urban-resolving simulations at a 900 m grid resolution and perform simulation scenarios aiming to isolate urbanization, clouds and land-sea circulations. Results show that urbanization correlates with the presence of shallow cumulus clouds, higher cloud bases, and increased cloud duration over the Galveston-Houston region compared to rural areas. These urban clouds benefit from the enhanced moist static energy that is favored by intensifying vertical mixing and moisture flux convergence. Urbanization raises the mean HI while mitigating its afternoon HI high. We found that the urban circulation dome overwhelms the sensitivity of the sea breeze to the urbanization. Instead, the influence of urbanization on cloud enhancement emerges as a crucial pathway responsible for reducing the high afternoon HI values. Moreover, uncertainties in SSTs are closely linked to the sensitivities of land-sea circulations, which in turn modulate UHI and HI.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JD041243","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152204","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}

引用次数: 0

Study on the Characteristics and the Parameterization of Effective Radius in Stratiform Precipitation Warm Cloud of Southeastern China Based on WRF-SBM Simulation 基于 WRF-SBM 模拟的中国东南部层状降水暖云有效半径特征及参数化研究

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-04 DOI: 10.1029/2024JD041153

Hengjia Cai, Xiaoli Liu, Yi Li

{"title":"Study on the Characteristics and the Parameterization of Effective Radius in Stratiform Precipitation Warm Cloud of Southeastern China Based on WRF-SBM Simulation","authors":"Hengjia Cai, Xiaoli Liu, Yi Li","doi":"10.1029/2024JD041153","DOIUrl":"https://doi.org/10.1029/2024JD041153","url":null,"abstract":"The study on the characteristic and the parameterization of cloud droplet effective radius (re) is important for the optimization of warm cloud microphysical schemes in numerical models. Based on numerical simulations combined with the four aircraft observations of stratiform warm clouds in Jiangxi, China, this work investigated their microphysical properties, focusing on the evolutionary pattern and the parameterization of re, as well as the correlation between re and the number concentration (Nc) of cloud droplet and liquid water path (LWP). It is found that there is a negative correlation between re and Nc, and the rate of the decrease could be increased by 2–4 times with a strengthening of collision-coalescence process. What's more, the direct introduction of collision-coalescence is conducted based on the existing re parameterization schemes, and the results show that it can perform well in most of collision-coalescence intensities. It is also found that LWP is positively correlated with re when re is less than 12 μm, after which the relationship changes to a negative correlation due to the impact of rainfall intensity.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JD041153","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142142363","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}

引用次数: 0

A NASA GISTEMPv4 Observational Uncertainty Ensemble 美国国家航空航天局 GISTEMPv4 观测不确定性集合

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-04 DOI: 10.1029/2023JD040179

Nathan Lenssen, Gavin A. Schmidt, Michael Hendrickson, Peter Jacobs, Matthew J. Menne, Reto Ruedy

{"title":"A NASA GISTEMPv4 Observational Uncertainty Ensemble","authors":"Nathan Lenssen, Gavin A. Schmidt, Michael Hendrickson, Peter Jacobs, Matthew J. Menne, Reto Ruedy","doi":"10.1029/2023JD040179","DOIUrl":"https://doi.org/10.1029/2023JD040179","url":null,"abstract":"The historical global temperature record is an essential data product for quantifying the variability and change of the Earth system. In recent years, better characterization of observational uncertainty in global and hemispheric trends has become available, but the methodologies are not necessarily applicable to analyses at smaller regional areas, or monthly or seasonal means, where station sparsity and other systematic issues contribute to greater uncertainty. This study presents a gridded uncertainty ensemble of historical surface temperature anomalies from the Goddard Institute for Space Studies (GISS) Surface Temperature (GISTEMP) product. This ensemble characterizes the complex spatial and temporal correlation structure of uncertainty, enabling better uncertainty propagation for climate and applied science in applications of historical temperature products at spatial scales from global to regional and temporal scales from centennial to monthly. This work details the methodology for generating the uncertainty ensemble, presents key statistics of the uncertainty evolution over space and time, and provides best practices for using the uncertainty ensemble in future studies. Summary statistics from the uncertainty ensemble agree well with the previous GISTEMP global uncertainty assessment, providing confidence in both.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142142365","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}

引用次数: 0