{"title":"Sea Surface Temperature in the East Central Pacific Ocean as a New Potential Predictor of Post-Monsoon Cyclonic Activity Over the Arabian Sea","authors":"Neeru Jaiswal, Randhir Singh","doi":"10.1029/2024GL109725","DOIUrl":"https://doi.org/10.1029/2024GL109725","url":null,"abstract":"<p>The study investigates Power Dissipation Index (PDI) of tropical cyclones (TCs) over the North Indian Ocean (NIO) and their relationship with sea surface temperature (SST) over the global ocean from 1982 to 2021. PDI of TCs over the Arabian Sea (AS) has a significant positive correlation with SST over the East Central Pacific Ocean (ECPO). This relationship appears to develop in March and peaks during the monsoon and post-monsoon seasons. Conversely, PDI of TCs over the Bay of Bengal has a significant negative association with SST over the Niño region. Regression analysis and numerical simulations reveal that heating over ECPO produces anomalous walker circulation, leading to favorable conditions for TC genesis and intensification over AS. This study has implication for forecasting TC activity and understanding how SST variability affects TCs over NIO in a changing climate.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL109725","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143530216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ning Kang, Qianli Ma, Jacob Bortnik, Murong Qin, Wen Li
{"title":"Ray Tracing of Whistler Mode Waves in Jupiter's Magnetosphere","authors":"Ning Kang, Qianli Ma, Jacob Bortnik, Murong Qin, Wen Li","doi":"10.1029/2024GL113727","DOIUrl":"https://doi.org/10.1029/2024GL113727","url":null,"abstract":"<p>Previous statistical studies have described the distributions and properties of whistler-mode waves in Jupiter's magnetosphere, but explaining these wave distributions requires modeling wave propagation from their generation near the magnetic equator. In this letter, we conduct ray tracing of whistler-mode waves based on realistic Jovian magnetic field and density models. The ray tracing results generally agree with the statistical wave distributions based on Juno measurements. The modeled ray paths show that high-frequency waves generated near the equator are confined within 20° magnetic latitude due to Landau damping, low-frequency waves can propagate to higher latitudes and lower <i>M</i>-shells, with changing wave normal angles, and a portion of low-frequency waves could propagate to high <i>M</i> shells at high latitudes. Our modeling results provide a theoretical interpretation of whistler-mode wave distributions and properties, providing essential insights for future radiation belt models at Jupiter.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL113727","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143533500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. H. Mauk, H. T. Smith, R. E. Johnson, V. Dols, F. Bagenal, J. E. P. Connerney, S. J. Bolton, G. Clark, D. K. Haggerty, P. Kollmann, C. P. Paranicas
{"title":"Diagnosing the Atmosphere of Jupiter's Volcanic Moon Io Using Energetic Neutral Atoms (ENAs)","authors":"B. H. Mauk, H. T. Smith, R. E. Johnson, V. Dols, F. Bagenal, J. E. P. Connerney, S. J. Bolton, G. Clark, D. K. Haggerty, P. Kollmann, C. P. Paranicas","doi":"10.1029/2024GL112668","DOIUrl":"https://doi.org/10.1029/2024GL112668","url":null,"abstract":"<p>During a Juno spacecraft encounter with Jupiter's volcanic moon Io (30 December 2023), the Jupiter Energetic Particle Detector Instrument (JEDI) observed Energetic Neutral Atoms (ENAs) of >150 keV oxygen and sulfur (O + S) coming from Io's mostly nightside atmosphere. JEDI lines-of-sight approached closest to Io between 1.31 and 1.49 Io radii (<i>R</i><sub>Io</sub>), above the predominantly SO<sub>2</sub> core atmosphere but imbedded within the extended atmosphere and corona of SO<sub>2</sub>, SO, O, and S. The ratio of O + S ENA intensities and O + S ion intensities estimated to be interacting with Io's atmosphere along JEDI lines-of-sight are 4%–7%. Those estimates are below expectations (∼11%–∼14%), but presently within uncertainties, based on integrations along the JEDI lines-of-sight through a prevailing but uncertain, local-time-symmetric model of Io's extended atmosphere. Expected ENA production rates will remain uncertain until detailed modeling of ion/atmosphere interactions are performed, and knowledge of charge exchange cross sections is verified.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL112668","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143533385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Revealing Spatial Variations of Earthquake Stress Drop and Peak Ground Acceleration Using a Non-Ergodic Modeling Framework","authors":"Shiying Nie, Yongfei Wang","doi":"10.1029/2024GL112043","DOIUrl":"https://doi.org/10.1029/2024GL112043","url":null,"abstract":"<p>Improving accuracy and reducing uncertainty in ground motion models (GMMs) are crucial for the safe design of infrastructure. Traditional GMMs often oversimplify source complexity, such as stress drop, due to high variability in estimation. This study aims to address this issue by extracting robust spatial variations in stress drop estimates and ground motion residuals. We introduce a non-ergodic modeling framework using Bayesian Gaussian Process regression to analyze data from over 5,000 earthquakes (M2-4.5) in the San Francisco Bay area. Our findings reveal consistent spatial patterns in non-ergodic stress drop and peak ground acceleration (PGA), providing a reliable approach to understanding the spatial distribution of stress drop and its link to regional tectonics. Furthermore, integrating source models derived from the non-ergodic stress drop into GMMs can effectively account for source effect in ground motions and reduce aleatory uncertainty. This study establishes a framework for utilizing stress drop data sets to enhance seismic hazard assessment.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL112043","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143533499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Snow Mass Recharge of the Greenland Ice Sheet Fueled by Intense Atmospheric River","authors":"Hannah Bailey, Alun Hubbard","doi":"10.1029/2024GL110121","DOIUrl":"https://doi.org/10.1029/2024GL110121","url":null,"abstract":"<p>Atmospheric rivers (ARs) have been linked with extreme rainfall and melt events across the Greenland ice sheet (GrIS), accelerating its mass loss. However, the impact of AR-fueled snowfall has received less attention, partly due to limited empirical evidence. Here, we relate new firn core stratigraphy and isotopic analyses with glacio-meteorological data sets from SE Greenland to examine an intense AR in mid-March 2022. We demonstrate that the associated snowfall—up to 11.6 gigatons d<sup>−1</sup>—delayed summer melt onset by11-days and offset Greenland's 2022 net mass loss by 8%. Since 2010, our synoptic analysis reveals that snow accumulation across SE Greenland increased by 20 mm water equivalent a<sup>−1</sup>, driven by enhanced Atlantic cyclonicity. We find that the impact of ARs on the GrIS is not exclusively negative and their capacity to contribute mass recharge may become increasingly significant under ongoing Arctic amplification and predicted poleward intrusion of mid-latitude moisture.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL110121","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143530218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Identifying a Pattern of Predictable Decadal North Pacific SST Variability in Historical Observations","authors":"Emily M. Gordon, Noah S. Diffenbaugh","doi":"10.1029/2024GL112729","DOIUrl":"https://doi.org/10.1029/2024GL112729","url":null,"abstract":"<p>Improving predictions of decadal climate variability is critical for reducing uncertainty in near-term climate change. Here we investigate the potential to improve prediction skill in the North Pacific by identifying predictable patterns of sea surface temperatures (SSTs) in climate simulations, and then applying them to observations. A convolutional neural network (CNN) is first trained to predict basin-wide SSTs in the North Pacific on 1–5 year time-scales in nine global climate models (GCMs), and a pattern of high skill is identified from the GCM data. This pattern of high skill learned from GCMs is then skillfully predicted by the CNN when given observations as inputs. The identified pattern is notably not the Pacific Decadal Oscillation, and instead corresponds to basinwide warming and cooling focused in the North Pacific Gyre. We conclude that investigating the mechanisms that contribute to predictability (rather than variability) is an effective avenue for improving near-term climate predictions.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL112729","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143530468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aaron G. Cahill, James McClure, Iain de Jonge-Anderson
{"title":"Natural Soils-Based Oxidation Mitigates Methane Leakage From Integrity Compromised Legacy Wells","authors":"Aaron G. Cahill, James McClure, Iain de Jonge-Anderson","doi":"10.1029/2024GL113522","DOIUrl":"https://doi.org/10.1029/2024GL113522","url":null,"abstract":"<p>An increasing number of legacy petroleum wells are reported to suffer integrity failure, releasing methane (CH<sub>4</sub>) into the subsurface and atmosphere. Subsurface released methane is reactively transported toward ground surface with a portion converted to carbon dioxide by soil microbes. Currently, the extent to which fugitive CH<sub>4</sub> oxidation occurs, including microbial taxa responsible and controlling parameters are poorly understood. Here, we examined fugitive CH<sub>4</sub> leakage at a legacy well in the Montney region of British Columbia, Canada and find up to 90% is oxidized at rates as high as 230 g of CH<sub>4</sub>/m<sup>2</sup> of soils/day during summer. Meanwhile, a profound difference in microbiome between soils at the wellhead and background was observed, while modeling suggests that prevailing seasonal temperature will moderate CH<sub>4</sub> oxidation extent. Overall, we find that filtration of fugitive CH<sub>4</sub> through natural soils can significantly reduce emissions of CH<sub>4</sub> and mitigate climate impacts from such sources.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL113522","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143521763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Heping Liu, Cheng Liu, Yanzhao Zhou, Qianyu Zhang, Ankur R. Desai, Khaled Ghannam, Jianping Huang, Gabriel G. Katul
{"title":"Is There a Scalar Atmospheric Surface Layer Within a Convective Boundary Layer? Implications for Flux Measurements","authors":"Heping Liu, Cheng Liu, Yanzhao Zhou, Qianyu Zhang, Ankur R. Desai, Khaled Ghannam, Jianping Huang, Gabriel G. Katul","doi":"10.1029/2024GL112619","DOIUrl":"https://doi.org/10.1029/2024GL112619","url":null,"abstract":"<p>Top-down entrainment shapes the vertical gradients of sensible heat, latent heat, and CO<sub>2</sub> fluxes, influencing the interpretation of eddy covariance (EC) measurements in the unstable atmospheric surface layer (ASL). Using large eddy simulations for convective boundary layer flows, we demonstrate that decreased temperature gradients across the entrainment zone increase entrainment fluxes by enhancing the entrainment velocity, amplifying the asymmetry between top-down and bottom-up flux contributions. These changes alter scalar flux profiles, causing flux divergence or convergence and leading to the breakdown of the constant flux layer assumption (CFLA) in the ASL. As a result, EC-measured fluxes either underestimate or overestimate “true” surface fluxes during divergence or convergence phases, contributing to energy balance non-closure. The varying degrees of the CFLA breakdown are a fundamental cause for the non-closure issue. These findings highlight the underappreciated role of entrainment in interpreting EC fluxes, addressing non-closure, and understanding site-to-site variability in flux measurements.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL112619","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Octav Marghitu, Adrian Blăgău, Vlad Constantinescu, Malcolm W. Dunlop, Guram Kervalishvili, Jan Rauberg, Jesper W. Gjerloev
{"title":"Investigation of Space Weather Effects by Swarm Magnetic Field Data: The SFAC Index","authors":"Octav Marghitu, Adrian Blăgău, Vlad Constantinescu, Malcolm W. Dunlop, Guram Kervalishvili, Jan Rauberg, Jesper W. Gjerloev","doi":"10.1029/2024GL112430","DOIUrl":"https://doi.org/10.1029/2024GL112430","url":null,"abstract":"<p>The three Swarm satellites provide an optimum, low Earth orbit (LEO) and multi-spacecraft platform, to explore for the first time the local correlation between field-aligned currents (FACs), auroral electrojets, and magnetic perturbations at the Earth's surface. By combining Swarm and ground magnetic field data, one can investigate systematically the full correlation chain, whose final link controls the ground induced currents and related space weather effects. We introduce an integrated FAC product, the Sheet FAC (SFAC) index, as a convenient measure of the <i>in-situ</i> FAC data, and explore the correlations SFAC-AE, SFAC-PEJ and SFAC-dH, with AE the standard auroral electrojet index, PEJ the local, Swarm based, polar electrojet index, and dH the horizontal magnetic field perturbation at the Earth's surface. Given the good SFAC-dH correlation, we also suggest an extension of SFAC to higher LEO satellites, which cannot observe any more the electrojet currents, but are fully capable to monitor SFAC.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL112430","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Direct Evidence of the Lower Atmosphere Perturbations Producing Abnormal Ionospheric Longitudinal Gradients During Quiescent Geomagnetic Conditions","authors":"Yuyan Jin, Biqiang Zhao, Xu Zhou, Honglian Hao, Guozhu Li, Xinan Yue, Zishen Li","doi":"10.1029/2024GL113648","DOIUrl":"https://doi.org/10.1029/2024GL113648","url":null,"abstract":"<p>An unusual case of a large ionospheric longitudinal gradient in East Asia on 11 May 2021 occurred during a geomagnetically-quiet period. It shows the largest east-west difference in electron density at Yamagawa and Wuhan stations when Kp < 2 for 13:00–17:00 LT in 2021. Ground- and satellite-based observations consistently confirm that there was a decrease in the west and an increase in the east of ∼125°E, with hemispherical symmetric with respect to the geomagnetic equator. The potential mechanism is further investigated through multi-observations of plasma drifts and neutral winds, provided by the Ionospheric Connections Explorer satellite and newly-established Sanya Incoherent Scatter Radar. The prominent longitudinal gradient in plasma drifts, electro-dynamically coupled with E-region winds, is suggested as the contributor for the east-west differences, together with the strong gradient of F-region winds in phase. This study provides direct evidence linking atmosphere perturbations to unusual longitudinal structure of terrestrial space plasma environment.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL113648","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}