AGU Advances最新文献_第10页

The Spillover of Tropospheric Ozone Increases Has Hidden the Extent of Stratospheric Ozone Depletion by Halogens 对流层臭氧增加的溢出效应掩盖了卤素对平流层臭氧的消耗程度

AGU Advances Pub Date : 2024-06-09 DOI: 10.1029/2023AV001154

Michael J. Prather

引用次数: 0

Unraveling the Atmospheric Energy Input and Ionization Due To EMIC-Driven Electron Precipitation From ELFIN Observations 从 ELFIN 观测中揭示 EMIC 驱动的电子沉降引起的大气能量输入和电离作用

AGU Advances Pub Date : 2024-06-07 DOI: 10.1029/2023AV001096

L. Capannolo, R. Marshall, W. Li, G. Berland, K. Duderstadt, N. Sivadas, D. L. Turner, V. Angelopoulos

{"title":"Unraveling the Atmospheric Energy Input and Ionization Due To EMIC-Driven Electron Precipitation From ELFIN Observations","authors":"L. Capannolo, R. Marshall, W. Li, G. Berland, K. Duderstadt, N. Sivadas, D. L. Turner, V. Angelopoulos","doi":"10.1029/2023AV001096","DOIUrl":"https://doi.org/10.1029/2023AV001096","url":null,"abstract":"Energetic electron precipitation (EEP) from the radiation belts into Earth's atmosphere leads to several profound effects (e.g., enhancement of ionospheric conductivity, possible acceleration of ozone destruction processes). An accurate quantification of the energy input and ionization due to EEP is still lacking due to instrument limitations of low-Earth-orbit satellites capable of detecting EEP. The deployment of the Electron Losses and Fields InvestigatioN (ELFIN) CubeSats marks a new era of observations of EEP with an improved pitch-angle (0°–180°) and energy (50 keV–6 MeV) resolution. Here, we focus on the EEP recorded by ELFIN coincident with electromagnetic ion cyclotron (EMIC) waves, which play a major role in radiation belt electron losses. The EMIC-driven EEP (∼200 keV–∼2 MeV) exhibits a pitch-angle distribution (PAD) that flattens with increasing energy, indicating more efficient high-energy precipitation. Leveraging the combination of unique electron measurements from ELFIN and a comprehensive ionization model known as Boulder Electron Radiation to Ionization (BERI), we quantify the energy input of EMIC-driven precipitation (on average, ∼3.3 × 10−2 erg/cm2/s), identify its location (any longitude, 50°–70° latitude), and provide the expected range of ion-electron production rate (on average, 100–200 pairs/cm3/s), peaking in the mesosphere—a region often overlooked. Our findings are crucial for improving our understanding of the magnetosphere-ionosphere-atmosphere system as they accurately specify the contribution of EMIC-driven EEP, which serves as a crucial input to state-of-the-art atmospheric models (e.g., WACCM) to quantify the accurate impact of EMIC waves on both the atmospheric chemistry and dynamics.","PeriodicalId":100067,"journal":{"name":"AGU Advances","volume":"5 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023AV001096","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141286935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Discounting Water for Optimal Carbon Gain as a Basis of Stomatal Closure 折算水分以获得最佳碳收益是气孔关闭的基础

AGU Advances Pub Date : 2024-06-05 DOI: 10.1029/2024AV001287

Mazen Nakad

{"title":"Discounting Water for Optimal Carbon Gain as a Basis of Stomatal Closure","authors":"Mazen Nakad","doi":"10.1029/2024AV001287","DOIUrl":"https://doi.org/10.1029/2024AV001287","url":null,"abstract":"The exchange of carbon dioxide and water vapor between terrestrial ecosystems and the atmosphere is regulated by stomata (small pores in the leaves of plants). Unsurprisingly, environmental factors controlling the opening and closure of stomata has been sought as early as 1800. One approach, popularized in the early 1970s, is a stomatal optimization framework. This framework is based on the hypothesis that plants optimize carbon gain subject to water loss or water availability constraints. This constraint optimization problem was solved in various forms assuming instantaneous adjustments of stomatal aperture to maximize a reward function with no future foresight or legacy effects. Holtzman et al. (2024, https://doi.org/10.1029/2023av001113) offers a novel approach that can diagnose the effective timescale over which the reward function maximization must be time-integrated. The developed method thus optimizes an integrated carbon gain function but adjusted by a discount factor subject to water availability in the root zone. The discount factor considers how the plant values carbon gain to save water and its timescale can be inferred from observations because the model is analytically tractable. The results suggest that the most important climate factor that determines this discount timescale is multi-annual mean of the longest dry period during the growing season. The findings highlight how local climate traits influence the spatial variation in ecosystem-level water use strategies. This sets the stage for expanding such a framework to cases where multiple constraints act in concert while operating at distinct time scales.","PeriodicalId":100067,"journal":{"name":"AGU Advances","volume":"5 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024AV001287","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141251483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

AGU Publications Updates Authorship Policy to Foster Greater Equity and Transparency in Global Research Collaborations AGU 出版物更新作者身份政策，促进全球研究合作的公平性和透明度

AGU Advances Pub Date : 2024-05-28 DOI: 10.1029/2024AV001298

Marguerite A. Xenopoulos, Ben Bond-Lamberty, Ankur R. Desai, Deborah Huntzinger, Paula R. Buchanan, Amy E. East, Arvind Singh, Paige Wooden, Kevin Jewett, Mia Ricci

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Bringing a Lens of Equity to Geoscience Qualifying Examinations 为地球科学资格考试引入公平视角

AGU Advances Pub Date : 2024-05-27 DOI: 10.1029/2024AV001260

Lilian A. Dove, Clare E. Singer, Sara E. Murphy

引用次数: 0

Column-Compound Extremes in the Global Ocean 全球海洋的柱状化合物极端值

AGU Advances Pub Date : 2024-05-23 DOI: 10.1029/2023AV001059

Joel Wong, Matthias Münnich, Nicolas Gruber

{"title":"Column-Compound Extremes in the Global Ocean","authors":"Joel Wong, Matthias Münnich, Nicolas Gruber","doi":"10.1029/2023AV001059","DOIUrl":"https://doi.org/10.1029/2023AV001059","url":null,"abstract":"Marine extreme events such as marine heatwaves, ocean acidity extremes and low oxygen extremes can pose a substantial threat to marine organisms and ecosystems. Such extremes might be particularly detrimental (a) when they are compounded in more than one stressor, and (b) when the extremes extend substantially across the water column, restricting the habitable space for marine organisms. Here, we use daily output of a hindcast simulation (1961–2020) from the ocean component of the Community Earth System Model to characterize such column-compound extreme events (CCX), employing a relative threshold approach to identify extremes and requiring them to extend vertically over at least 50 m. The diagnosed CCX are prevalent, occupying worldwide in the 1960s about 1% of the volume contained within the top 300 m. Over the duration of our simulation, CCX become more intense, last longer, and occupy more volume, driven by the trends in ocean warming and ocean acidification. For example, the triple CCX expanded 39-fold, now last 3-times longer, and became 6-times more intense since the early 1960s. Removing this effect with a moving baseline permits us to better understand the key characteristics of CCX, revealing a typical duration of 10–30 days and a predominant occurrence in the Tropics and high latitudes, regions of high potential biological vulnerability. Overall, the CCX fall into 16 clusters, reflecting different patterns and drivers. Triple CCX are largely confined to the tropics and the North Pacific and tend to be associated with the El Niño-Southern Oscillation.","PeriodicalId":100067,"journal":{"name":"AGU Advances","volume":"5 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023AV001059","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141085072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thank You to Our 2023 Peer Reviewers 感谢 2023 年同行评审员

AGU Advances Pub Date : 2024-04-30 DOI: 10.1029/2024AV001290

Ana Barros, Thorsten Becker, M. Bayani Cardenas, Eric Davidson, Nicolas Gruber, Eileen Hofmann, Mary Hudson, Tissa Illangasekare, Sarah Kang, Alberto Montanari, Marcos Moreno, Francis Nimmo, Larry Paxton, Francois Primeau, Vincent Salters, David Schimel, Bjorn Stevens, Hang Su, Jessica Tierney, Susan Trumbore, Donald Wuebbles, Peter Zeitler, Binzheng Zhang, Xi Zhang

引用次数: 0

Unveiling Energetic Particle Dynamics in the Near-Earth Environment From CubeSat Missions 从立方体卫星任务中揭示近地环境中的高能粒子动力学

AGU Advances Pub Date : 2024-04-26 DOI: 10.1029/2024AV001256

Xinlin Li

引用次数: 0

Emergent Trends Complicate the Interpretation of the United States Drought Monitor (USDM) 新趋势使美国干旱监测仪 (USDM) 的解读变得复杂

AGU Advances Pub Date : 2024-04-25 DOI: 10.1029/2023AV001070

Zhiying Li, Jason E. Smerdon, Richard Seager, Noel Siegert, Justin S. Mankin

{"title":"Emergent Trends Complicate the Interpretation of the United States Drought Monitor (USDM)","authors":"Zhiying Li, Jason E. Smerdon, Richard Seager, Noel Siegert, Justin S. Mankin","doi":"10.1029/2023AV001070","DOIUrl":"https://doi.org/10.1029/2023AV001070","url":null,"abstract":"Effective drought management must be informed by an understanding of whether and how current drought monitoring and assessment practices represent underlying nonstationary climate conditions, either naturally occurring or forced by climate change. Here we investigate the emerging climatology and associated trends in drought classes defined by the United States Drought Monitor (USDM), a weekly product that, since 2000, has been used to inform drought management in the United States. The USDM classifies drought intensity based in part on threshold percentiles in key hydroclimate quantities. Here we assess how those USDM-defined drought threshold percentiles have changed over the last 23 years, examining precipitation, runoff, soil moisture (SM), terrestrial water storage (TWS), vapor pressure deficit (VPD), and near-surface air temperature. We also assess underlying trends in the frequency of drought classifications across the U.S. Our analysis suggests that the frequency of drought class occurrence is exceeding the threshold percentiles defined by the USDM in a number of regions in the United States, particularly in the American West, where the last 23 years have emerged as a prolonged dry period. These trends are also reflected in percentile-based thresholds in precipitation, runoff, SM, TWS, VPD, and temperature. Our results emphasize that while the USDM appears to be accurately reflecting observed nonstationarity in the physical climate, such trends raise critical questions about whether and how drought diagnosis, classification, and monitoring should address long-term intervals of wet and dry periods or trends.","PeriodicalId":100067,"journal":{"name":"AGU Advances","volume":"5 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023AV001070","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140641928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An Extreme Auroral Electrojet Spike During 2023 April 24th Storm 2023 年 4 月 24 日风暴期间的极端极光电喷峰

AGU Advances Pub Date : 2024-04-25 DOI: 10.1029/2023AV001101

Ying Zou, Jesper W. Gjerloev, Shin Ohtani, Matt Friel, Jun Liang, Larry L. Lyons, Yangyang Shen, Jiang Liu, Li-Jen Chen, Banafsheh Ferdousi, Alex Chartier, Sarah Vines, Colin L. Waters

{"title":"An Extreme Auroral Electrojet Spike During 2023 April 24th Storm","authors":"Ying Zou, Jesper W. Gjerloev, Shin Ohtani, Matt Friel, Jun Liang, Larry L. Lyons, Yangyang Shen, Jiang Liu, Li-Jen Chen, Banafsheh Ferdousi, Alex Chartier, Sarah Vines, Colin L. Waters","doi":"10.1029/2023AV001101","DOIUrl":"https://doi.org/10.1029/2023AV001101","url":null,"abstract":"Abrupt variations of auroral electrojets can induce geomagnetically induced currents, and the ability to model and forecast them is a pressing goal of space weather research. We report an auroral electrojet spike event that is extreme in magnitude, explosive in nature, and global in spatial extent that occurred on 24 April 2023. The event serves as a fundamental test of our understanding of the response of the geospace system to solar wind dynamics. Our results illustrate new and important characteristics that are drastically different from existing knowledge. Most important findings include (a) the event was only of ∼5-min duration and was limited to a narrow (2°–3°) band of diffuse aurora; (b) the longitudinal span covered the entire nightside sector, possibly extending to the dayside; (c) the trigger seems to be a transient solar wind dynamic pressure pulse. In comparison, substorms usually last 1–2 hr and span almost the entire latitudinal width of the auroral oval. Magnetic perturbation events (MPEs) span hundreds km in radius. Both substorms and MPEs are mainly driven by disturbances in the magnetotail. A possible explanation is that the pressure pulse compresses the magnetosphere and enhances diffuse precipitation of electrons and protons from the inner plasma sheet, which elevates the ionospheric conductivity and intensifies the auroral electrojet. Therefore, the event exhibits a potentially new type of geomagnetic disturbance and highlights a solar wind driver that is enormously influential in driving extreme space weather events.","PeriodicalId":100067,"journal":{"name":"AGU Advances","volume":"5 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023AV001101","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140641923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0