Atmospheric and Oceanic Science Letters最新文献

{"title":"Clarifying the relationship between PM2.5 and ozone complex pollution and synoptic patterns in a typical petrochemical city in the Bohai Rim region of China: Implications for air pollution forecasting and control","authors":"Yongxin Yan ,&nbsp;Cong An ,&nbsp;Junling Li ,&nbsp;Yuanyuan Ji ,&nbsp;Rui Gao ,&nbsp;Hong Wang ,&nbsp;Fanyi Shang ,&nbsp;Linlin Ma ,&nbsp;Xiaoshuai Gao ,&nbsp;Hong Li","doi":"10.1016/j.aosl.2024.100539","DOIUrl":"10.1016/j.aosl.2024.100539","url":null,"abstract":"<div><div>Meteorological conditions are vital to PM_2.5 and ozone (O₃) complex pollution. Herein, the T-mode principal component analysis method was employed to objectively classify the 925-hPa geopotential height field of Dongying from 2017 to 2022. Synoptic patterns associated with four pollution types—namely, PM_2.5-only pollution, O₃-only pollution, Co-occurring of PM_2.5 and O₃ pollution, Non-occurring of PM_2.5 and O₃ pollution—were characterized at different time scales. The results indicated that synoptic classes conducive to PM_2.5-only pollution were “high-pressure top front”, “offshore high-pressure rear”, and “high-pressure inside”, while those conducive to O₃-only pollution were “offshore high-pressure rear”, “subtropical high”, and “high and low systems”. The Co-occurring of PM_2.5 and O₃ pollution were influenced by high pressure, and the Non-occurring of PM_2.5 and O₃ pollution were linked to precipitation and strong northerly winds. The variation in dominant synoptic patterns is crucial in the frequency changes of the four pollution types, which was further validated through the analysis of typical cases. Under the favorable meteorological conditions of high-pressure control with strong northerly winds or a subtropical high and inverted trough both with strong precipitation, there is potential to achieve coordinated control of PM_2.5 and O₃ in Dongying. Additionally, measures like artificially manipulating local humidity could be adopted to alleviate pollution levels. This study reveals the importance of comprehending the meteorological factors contributing to the formation of PM_2.5 and O₃ complex pollution for the improvement of urban air quality in the Bohai Rim region of China when emissions are high and the concentration of air pollutants exhibits high meteorological sensitivity.</div><div>摘要</div><div>本文研究了中国环渤海地区典型石化城市东营市近年来PM_2.5与臭氧复合污染的天气形势特征. 结果表明, 有利于促发PM_2.5单独污染的环流形势与高压顶前部型, 海上高压后部型, 高压内部型有关; 有利于促发臭氧单独污染的天气型与海上高压后部, 副高和高低值系统有关; PM_2.5和臭氧双高污染的发生主要受高压系统的控制; 不利于PM_2.5和臭氧污染发生的环流类型则与降水和较强的偏北风有关. 优势天气型的变化是导致四种污染类型发生频率变化的重要因素. 研究结果揭示了当一次排放处于高位, 且空气污染物浓度变化具有高气象敏感性的情况下, 弄清PM_2.5和臭氧复合污染的气象成因对于中国环渤海地区城市空气质量持续改善的重要意义.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"17 6","pages":"Article 100539"},"PeriodicalIF":2.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Coordinated control of PM2.5 and O3: Investigating the physical and chemical processes underlying regional complex air pollution","authors":"Aijun Ding ,&nbsp;Meigen Zhang ,&nbsp;Likun Xue","doi":"10.1016/j.aosl.2024.100562","DOIUrl":"10.1016/j.aosl.2024.100562","url":null,"abstract":"","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"17 6","pages":"Article 100562"},"PeriodicalIF":2.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Vertical distributions of VOCs in the Tibetan Plateau background region","authors":"Xuanxuan Xue ,&nbsp;Fugeng Zha ,&nbsp;Yinghong Wang ,&nbsp;Yang Zhang ,&nbsp;Yu Wang ,&nbsp;Ying Shen ,&nbsp;Yanyu Kang ,&nbsp;Dan Yao ,&nbsp;Guiqian Tang ,&nbsp;Jianchun Bian ,&nbsp;Yuesi Wang","doi":"10.1016/j.aosl.2024.100516","DOIUrl":"10.1016/j.aosl.2024.100516","url":null,"abstract":"<div><div>Exploring the vertical variation in volatile organic compounds (VOCs) in background regions can provide information on the spatial distribution of pollutants, providing a scientific basis for atmospheric pollution prevention and control strategies. From 15 August to 5 September 2023, at the Southeast Tibet Mountain Comprehensive Environmental Observation Station (SETS), a tethered balloon was used to sample VOCs every 100 m from the ground to 1000 m. A total of 403 air bag samples were collected, and 39 vertical profiles of VOCs were obtained. Ninety-two VOC species were detected. The VOC concentration at the SETS did not change significantly vertically, and the average VOC concentration was 11.1 ± 2.4 ppbv. The main components were alkanes (51.4 %), alkenes (18.7 %), and halohydrocarbons (18.1 %). There was no obvious diurnal change in VOCs and no significant difference between the different layers. When the surface VOC concentration was less than 10 ppbv, the concentrations, components, and sources of VOCs were evenly distributed vertically, and the main sources of VOCs at different heights were vehicle exhaust and background. When the surface VOC concentration exceeded 10 ppbv, the VOC concentration gradually decreased with height. The proportion of alkanes in surface VOCs increased, and the source was mainly vehicle exhaust. This study confirmed that VOCs are vertically homogeneous in the background of the Tibetan Plateau, emphasizing the importance of vehicle emissions as a potential source of VOCs.</div><div>摘要</div><div>研究背景区域挥发性有机物 (VOCs) 的垂直变化规律, 可以提供污染物的空间分布信息, 为制定大气污染防治策略提供科学依据. 2023年夏季, 利用系留气艇对藏东南背景区域VOCs垂直分布规律进行研究, 共获取92种VOC的39条垂直廓线. 结果表明, VOC浓度垂直分布均一, 平均浓度为11.1 ± 2.4 ppbv; 主要成分为烷烃 (51.4 %), 烯烃 (18.7 %) 和卤代烃 (18.1 %). 地表VOC浓度小于10 ppbv时, 不同高度VOCs的主要来源为机动车尾气和背景贡献. 而地表VOC浓度超过10 ppbv时, 烷烃占比增加, 来源以机动车尾气为主. 该研究证实了青藏高原VOC在垂直方向上分布均一, 强调了机动车排放作为VOCs潜在来源的重要性.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"17 6","pages":"Article 100516"},"PeriodicalIF":2.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141028294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Global warming intensifies once-in-a-decade extreme precipitation in summer in China","authors":"Aoqi Zhou ,&nbsp;Chaoxia Yuan","doi":"10.1016/j.aosl.2024.100561","DOIUrl":"10.1016/j.aosl.2024.100561","url":null,"abstract":"<div><div>The intensification of extreme precipitation (EP) under global warming presents a substantial risk to human safety and societal progress. Studying the specific impacts of global warming on rare EP events in China not only enhances the comprehension of these shifts, but also paves the way for the development of proactive strategies to alleviate associated damages. Results from large-ensemble simulation data demonstrate that global warming has led to an enhancement in once-in-a-decade EP events in parts of western and central China over the past few decades, with the strengthening of the South Asia high (SAH) caused by global warming playing a dominant role. The strengthening of the SAH corresponds to an intensification and westward extension of the western Pacific subtropical high in the lower troposphere. The region between these two systems experiences enhanced upward motion and increased southwesterly water vapor transport, leading to a rise in climatological precipitation in western and central China, thereby raising the threshold for once-in-a-decade EP events.</div><div>摘要</div><div>全球变暖下极端降水 （EP） 的加剧对人类安全和社会发展构成了重大威胁. 研究全球变暖对中国罕见极端降水事件的影响， 不仅能加深大家对这些变化的理解， 还为制定应对政策铺平了道路. 大样本模拟数据表明， 在过去几十年中， 全球变暖加剧了中国西部和中部部分地区十年一遇的极端降水事件， 其中因全球变暖而增强的南亚高压 （SAH） 起到了主导作用. SAH的增强与对流层低层西太副高的增强西伸密切相关. 这两个系统间的区域经历了更强的上升运动和增强的西南水汽输送， 导致中国西部和中部的气候态降水增加， 从而提高了十年一遇极端降水事件的阈值.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"18 4","pages":"Article 100561"},"PeriodicalIF":2.3,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144169723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating vector winds over eastern China in 2022 predicted by the CMA-MESO model and ECMWF forecast","authors":"Fang Huang ,&nbsp;Mingjian Zeng ,&nbsp;Zhongfeng Xu ,&nbsp;Boni Wang ,&nbsp;Ming Sun ,&nbsp;Hangcheng Ge ,&nbsp;Shoukang Wu","doi":"10.1016/j.aosl.2024.100559","DOIUrl":"10.1016/j.aosl.2024.100559","url":null,"abstract":"<div><div>Vector winds play a crucial role in weather and climate, as well as the effective utilization of wind energy resources. However, limited research has been conducted on treating the wind field as a vector field in the evaluation of numerical weather prediction models. In this study, the authors treat vector winds as a whole by employing a vector field evaluation method, and evaluate the mesoscale model of the China Meteorological Administration (CMA-MESO) and ECMWF forecast, with reference to ERA5 reanalysis, in terms of multiple aspects of vector winds over eastern China in 2022. The results show that the ECMWF forecast is superior to CMA-MESO in predicting the spatial distribution and intensity of 10-m vector winds. Both models overestimate the wind speed in East China, and CMA-MESO overestimates the wind speed to a greater extent. The forecasting skill of the vector wind field in both models decreases with increasing lead time. The forecasting skill of CMA-MESO fluctuates more and decreases faster than that of the ECMWF forecast. There is a significant negative correlation between the model vector wind forecasting skill and terrain height. This study provides a scientific evaluation of the local application of vector wind forecasts of the CMA-MESO model and ECMWF forecast.</div><div>摘要</div><div>本文利用矢量场评估VFE方法, 从矢量场角度系统性评估CMA-MESO模式与ECMWF模式对2022年华东地区10 m高度矢量风场的预报技巧. 结果表明, ECMWF模式对矢量风场空间分布与风场强度的预报均优于CMA-MESO模式. CMA-MESO模式明显高估了矢量风场的强度. 模式预报技巧随着预报时效的延长而下降, 其中以CMA-MESO模式的预报技巧波动更大, 衰减更迅速. 本研究将为CMA-MESO模式与ECMWF模式风场预报产品的本地化应用, 提供一个科学的评估依据.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"18 4","pages":"Article 100559"},"PeriodicalIF":2.3,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144169722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fluctuations in the relationship between the Silk Road Pattern and the summer North Atlantic Oscillation","authors":"Yong Liu ,&nbsp;Zhencai Du","doi":"10.1016/j.aosl.2024.100558","DOIUrl":"10.1016/j.aosl.2024.100558","url":null,"abstract":"<div><div>This study investigated the fluctuations in the relationship between the Silk Road Pattern (SRP) and the boreal summer North Atlantic Oscillation (SNAO). The results indicated that the SRP–SNAO relationship was relatively weak during 1958–2022, which was primarily due to fluctuations, particularly the reversal in their relationship since the late 1990s. Using wavelet coherence analysis, the authors identified a strong SRP–SNAO linkage on a 4–8-yr timescale, in particular during the mid-1970s to the early/mid-1990s. This strong linkage is mainly attributable to the intensification and eastward movement of the southern part of the SNAO around the mid/late 1970s, which favored the strong connection between the SNAO and the SRP. Additionally, the interdecadal changes of the atmospheric circulations over the North Atlantic and Eurasia around the mid/late 1970s that resembled the circulation anomalies related to the strong SRP–SNAO linkage, may also have provided a favorable background for the strong connection between the two teleconnections. These findings on the fluctuations in the SRP–SNAO linkage may offer important implications for understanding the impact of the SNAO on the SRP and the variability of the SRP.</div><div>摘要</div><div>本文利用近60年大气再分析数据, 研究了丝绸之路型遥相关 (Silk Road Pattern, SRP) 与夏季北大西洋涛动 (North Atlantic Oscillation, SNAO) 关系的不稳定性及其可能成因. 结果表明, 近60年来, SRP与SNAO的关系具有明显的不稳定性. 两者关系在1970s中期至1990s中期显著增强, 特别在4-8年时间尺度上. 两者关系的增强主要与1970s中后期以来SNAO南部中心增强, 位置东移有关. 同时, 北大西洋和欧亚区域夏季大气环流在1970s末的年代际异常也为两者之间关系的增强提供了有利的气候背景.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"18 4","pages":"Article 100558"},"PeriodicalIF":2.3,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144169721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Employment of an Arctic sea-ice data assimilation scheme in the coupled climate system model FGOALS-f3-L and its preliminary results","authors":"Yuyang Guo ,&nbsp;Yongqiang Yu ,&nbsp;Jiping Liu","doi":"10.1016/j.aosl.2024.100553","DOIUrl":"10.1016/j.aosl.2024.100553","url":null,"abstract":"<div><div>Arctic sea ice is an important component of the global climate system and has experienced rapid changes during in the past few decades, the prediction of which is a significant application for climate models. In this study, a Localized Error Subspace Transform Kalman Filter is employed in a coupled climate system model (the Flexible Global Ocean–Atmosphere–Land System Model, version f3-L (FGOALS-f3-L)) to assimilate sea-ice concentration (SIC) and sea-ice thickness (SIT) data for melting-season ice predictions. The scheme is applied through the following steps: (1) initialization for generating initial ensembles; (2) analysis for assimilating observed data; (3) adoption for dividing ice states into five thickness categories; (4) forecast for evolving the model; (5) resampling for updating model uncertainties. Several experiments were conducted to examine its results and impacts. Compared with the control experiment, the continuous assimilation experiments (CTNs) indicate assimilations improve model SICs and SITs persistently and generate realistic initials. Assimilating SIC+SIT data better corrects overestimated model SITs spatially than when only assimilating SIC data. The continuous assimilation restart experiments indicate the initials from the CTNs correct the overestimated marginal SICs and overall SITs remarkably well, as well as the cold biases in the oceanic and atmospheric models. The initials with SIC+SIT assimilated show more reasonable spatial improvements. Nevertheless, the SICs in the central Arctic undergo abnormal summer reductions, which is probably because overestimated SITs are reduced in the initials but the strong seasonal cycle (summer melting) biases are unchanged. Therefore, since systematic biases are complicated in a coupled system, for FGOALS-f3-L to make better ice predictions, oceanic and atmospheric assimilations are expected required.</div><div>摘要</div><div>当前, 快速变化的北极海冰对全球气候有重要影响, 海冰的预报是气候模式的重要应用方向之一. 本研究基于PDAF同化框架, 使用LESTKF方法将北极海冰密集度 (SIC) 和厚度 (SIT) 观测数据同化到气候系统模式FGOALS-f3-L中开展融化季节的海冰预测. 同化的引入共分为集合初始化, 同化分析, 分析场引入, 模式预报, 集合重采样等五个步骤. 试验表明, 连续同化可以持续改进模式模拟的SIC和SIT并生成接近真实的初始场, 同时同化SIC和SIT比只同化SIC能更好地纠正SIT的空间偏差. 利用连续同化生成的初始场进行预报, 能够显著减少海冰边缘的SIC多偏差, 整体的SIT厚偏差以及海洋和大气中的冷偏差, 使用同化了SIC和SIT的初始场能带来更合理的空间改进. 但受模式中海冰季节循环偏强的影响, 预报的夏季海冰会出现偏少, 这表明在耦合系统中准确预报海冰还需纳入海洋和大气同化.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"18 4","pages":"Article 100553"},"PeriodicalIF":2.3,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144169720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Variation in the permafrost active layer over the Tibetan Plateau during 1980–2020","authors":"","doi":"10.1016/j.aosl.2024.100536","DOIUrl":"10.1016/j.aosl.2024.100536","url":null,"abstract":"<div><p>The active layer, acting as an intermediary of water and heat exchange between permafrost and atmosphere, greatly influences biogeochemical cycles in permafrost areas and is notably sensitive to climate fluctuations. Utilizing the Chinese Meteorological Forcing Dataset to drive the Community Land Model, version 5.0, this study simulates the spatial and temporal characteristics of active layer thickness (ALT) on the Tibetan Plateau (TP) from 1980 to 2020. Results show that the ALT, primarily observed in the central and western parts of the TP where there are insufficient station observations, exhibits significant interdecadal changes after 2000. The average thickness on the TP decreases from 2.54 m during 1980–1999 to 2.28 m during 2000–2020. This change is mainly observed in the western permafrost region, displaying a sharp regional inconsistency compared to the eastern region. A persistent increasing trend of ALT is found in the eastern permafrost region, rather than an interdecadal change. The aforementioned changes in ALT are closely tied to the variations in the surrounding atmospheric environment, particularly air temperature. Additionally, the area of the active layer on the TP displays a profound interdecadal change around 2000, arising from the permafrost thawing and forming. It consistently decreases before 2000 but barely changes after 2000. The regional variation in the permafrost active layer over the TP revealed in this study indicates a complex response of the contemporary climate under global warming.</p><p>摘要</p><p>活动层是多年冻土和大气之间的缓冲层, 对气候波动十分敏感, 其冻融变化对多年冻土区的地球生物化学循环有较大影响. 本研究利用高分辨率气象数据集CMFD和陆面过程模式CLM5.0模拟分析了青藏高原1980–2020年活动层的变化. 结果表明: 青藏高原的活动层厚度在2000年后有显著的年代际变化, 青藏高原整体活动层厚度由1980–1999的2.54 m减少到2000–2020年的2.28 m. 这种变化主要发生在西部的多年冻土区, 与东部相比存在明显的区域差异. 在东部, 多年冻土区的活动层厚度呈持续增加趋势, 而不是年代际变化. 此外, 活动层面积在2000年也发生了年代际突变, 之前持续下降, 但之后几乎没有变化. 本文还发现青藏高原多年冻土活动层的区域变化受到气温和降水等环境因子的显著影响, 这反映了其在全球变暖背景下对气候变化的复杂响应.</p></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"17 5","pages":"Article 100536"},"PeriodicalIF":2.3,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1674283424000850/pdfft?md5=5bdbe6b3d2873446dbdfcebd7b8938c7&pid=1-s2.0-S1674283424000850-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141392826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Future changes in precipitation and water availability over the Tibetan Plateau projected by CMIP6 models constrained by climate sensitivity","authors":"Hui Qiu ,&nbsp;Tianjun Zhou ,&nbsp;Liwei Zou ,&nbsp;Jie Jiang ,&nbsp;Xiaolong Chen ,&nbsp;Shuai Hu","doi":"10.1016/j.aosl.2024.100537","DOIUrl":"10.1016/j.aosl.2024.100537","url":null,"abstract":"<div><p>Precipitation projections over the Tibetan Plateau (TP) show diversity among existing studies, partly due to model uncertainty. How to develop a reliable projection remains inconclusive. Here, based on the IPCC AR6–assessed likely range of equilibrium climate sensitivity (ECS) and the climatological precipitation performance, the authors constrain the CMIP6 (phase 6 of the Coupled Model Intercomparison Project) model projection of summer precipitation and water availability over the TP. The best estimates of precipitation changes are 0.24, 0.25, and 0.45 mm d⁻¹ (5.9 %, 6.1 %, and 11.2 %) under the Shared Socioeconomic Pathway (SSP) scenarios of SSP1–2.6, SSP2–4.5, and SSP5–8.5 from 2050–2099 relative to 1965–2014, respectively. The corresponding constrained projections of water availability measured by precipitation minus evaporation (P–E) are 0.10, 0.09, and 0.22 mm d⁻¹ (5.7 %, 4.9 %, and 13.2 %), respectively. The increase of precipitation and P–E projected by the high-ECS models, whose ECS values are higher than the upper limit of the likely range, are about 1.7 times larger than those estimated by constrained projections. Spatially, there is a larger increase in precipitation and P–E over the eastern TP, while the western part shows a relatively weak difference in precipitation and a drier trend in P–E. The wetter TP projected by the high-ECS models resulted from both an approximately 1.2–1.4 times stronger hydrological sensitivity and additional warming of 0.6 °C–1.2 °C under all three scenarios during 2050–2099. This study emphasizes that selecting climate models with climate sensitivity within the likely range is crucial to reducing the uncertainty in the projection of TP precipitation and water availability changes.</p><p>摘要</p><p>青藏高原是气候变化敏感区, 可靠的气候预估对气候变化应对至关重要. 青藏高原夏季降水变化的预估结果在CMIP6气候模式间存在较大的不确定性, 原因部分地和这些模式对温室气体强迫的敏感度不同有关. 作者在对CMIP6模式性能进行评估基础上, 选择了具有较高气候态降水模拟技巧的模式用于预估研究, 并根据IPCC AR6估算的平衡态气候敏感度 (ECS) 的可能性范围, 对青藏高原夏季降水的中远期 (2050–2099) 变化进行约束. 结果表明, 在SSP1–2.6, SSP2–4.5 和 SSP5–8.5情景下, 青藏高原夏季降水将分别增多0.24, 0.25 和 0.45 mm d⁻¹ (5.9 %, 6.1 %, 和 11.2 %), 水资源可用性 (P–E) 将分别增加0.10, 0.09和0.22 mm d⁻¹(5.7 %, 4.9 % 和13.2 %) . 与约束预估相比, 高ECS模式预估的水文敏感度约为约束后的1.2–1.4倍, 升温幅度偏高0.6 °C–1.2 °C, 这二者共同导致高ECS模式预估的高原降水增幅约为约束预估的1.7倍. 本文指出气候敏感度是影响未来青藏高原水资源预估不确定性的重要来源, 同时基于IPCC AR6对ECS的最佳估算, 给出了高原夏季降水和水资源的最佳预估结果.</p></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"17 5","pages":"Article 100537"},"PeriodicalIF":2.3,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1674283424000862/pdfft?md5=68c7bec658cb012bffbe4f08b8df1040&pid=1-s2.0-S1674283424000862-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142161546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"A study on the simulation of carbon and water fluxes of Dangxiong alpine meadow and its response to climate change","authors":"","doi":"10.1016/j.aosl.2024.100507","DOIUrl":"10.1016/j.aosl.2024.100507","url":null,"abstract":"<div><p>The alpine meadow ecosystem accounts for 27 % of the total area of the Tibetan Plateau and is also one of the most important vegetation types. The Dangxiong alpine meadow ecosystem, located in the south-central part of the Tibetan Plateau, is a typical example. To understand the carbon and water fluxes, water use efficiency (WUE), and their responses to future climate change for the alpine meadow ecosystem in the Dangxiong area, two parameter estimation methods, the Model-independent Parameter Estimation (PEST) and the Dynamic Dimensions Search (DDS), were used to optimize the Biome-BGC model. Then, the gross primary productivity (GPP) and evapotranspiration (ET) were simulated. The results show that the DDS parameter calibration method has a better performance. The annual GPP and ET show an increasing trend, while the WUE shows a decreasing trend. Meanwhile, ET and GPP reach their peaks in July and August, respectively, and WUE shows a “dual-peak” pattern, reaching peaks in May and November. Furthermore, according to the simulation results for the next nearly 100 years, the ensemble average GPP and ET exhibit a significant increasing trend, and the growth rate under the SSP5–8.5 scenario is greater than that under the SSP2–4.5 scenario. WUE shows an increasing trend under the SSP2–4.5 scenario and a significant increasing trend under the SSP5–8.5 scenario. This study has important scientific significance for carbon and water cycle prediction and vegetation ecological protection on the Tibetan Plateau.</p><p>摘要</p><p>全球气候变化对青藏高原生态系统产生了深远影响, 暖湿化背景下青藏高原植被碳, 水通量变化趋势值得关注. 高寒草甸是青藏高原最主要的植被类型之一, 为理解青藏高原当雄地区高寒草甸生态系统碳, 水通量, 水分利用效率及其对未来气候变化的响应, 本研究利用PEST和DDS两种参数率定方法优化Biome-BGC模型, 进而模拟2000–2019年当雄站的总初级生产力 (GPP) 和蒸散量 (ET) . 研究结果表明: DDS参数率定方法具有更优的性能. GPP和ET在研究时段内呈上升趋势, 而水分利用效率 (WUE) 则呈下降趋势. 同时, ET和GPP分别在7月和8月达到峰值, 而WUE则呈“双峰”变化, 分别于5月和11月达到峰值. 此外, 未来近百年的模拟表明GPP和ET的集合平均结果呈显著增加趋势, 其中在SSP5–8.5情景下的增速大于SSP2–4.5情景. WUE在SSP2–4.5情景下呈增加趋势, 而在SSP5–8.5情景下呈显著增加趋势. 本研究结果可为青藏高原碳, 水循环预测研究和植被生态保护的应用研究提供参考和借鉴.</p></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"17 5","pages":"Article 100507"},"PeriodicalIF":2.3,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1674283424000564/pdfft?md5=321f26220b000716c9b88ec2f566bdec&pid=1-s2.0-S1674283424000564-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140774115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}