D. Keir, A. La Rosa, C. Pagli, H. Wang, A. Ayele, E. Lewi, F. Monterroso, M. Raggiunti
{"title":"The 2024 Fentale Diking Episode in a Slow Extending Continental Rift","authors":"D. Keir, A. La Rosa, C. Pagli, H. Wang, A. Ayele, E. Lewi, F. Monterroso, M. Raggiunti","doi":"10.1029/2024GL113214","DOIUrl":"https://doi.org/10.1029/2024GL113214","url":null,"abstract":"<p>Dikes can contribute to rifting, but the space-time behavior and role of magma in young and slowly extending continental rifts is unclear. We use InSAR and seismicity during the 2024 Fentale intrusion in the Main Ethiopian rift (MER) to understand magma-assisted rifting at slow extension rates (5 mm/yr). From 2021 to mid-2024, the Fentale Volcanic Complex (FVC) uplifted up to 6 cm. From mid-September 2024, upper crustal diking started northwards along the rift, initially with subdued seismicity. From late-September to early November, dike opening increased to ∼2 m and propagated a total of ∼14 km north, causing increased seismicity from normal faulting. The dike made ∼90% of the total geodetic moment, with the rest from faulting. The character of the event is similar to rifting episodes at mid-ocean ridges and demonstrates that episodic diking can occur in young, slow extending continent rifts but must be more infrequent.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL113214","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143564615","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":"Enhanced Moisture Retrieval Near Boundary Layer From Satellite Sounder Data Through Atmospheric-Surface Radiance Separation","authors":"Ronglian Zhou, Di Di, Jun Li, Zhenglong Li","doi":"10.1029/2024GL113404","DOIUrl":"https://doi.org/10.1029/2024GL113404","url":null,"abstract":"<p>Accurate satellite-based retrieval of boundary-layer water vapor over land is crucial for understanding the Earth-atmosphere system but remains challenging due to the interaction of surface parameters on low-level atmosphere-sensitive channels. This study proposes a novel approach to explicitly extract the upwelling atmospheric radiance (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>R</mi>\u0000 <mi>a</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${R}_{mathrm{a}}$</annotation>\u0000 </semantics></math>) from the total radiance (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>R</mi>\u0000 <mi>t</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${R}_{mathrm{t}}$</annotation>\u0000 </semantics></math>) observed by the Infrared Atmospheric Sounding Interferometer (IASI), using a Residual Multi-Layer Perceptron model. A modified one-dimensional variational algorithm for surface-free radiances is also developed. The radiance extraction model, trained on simulated IASI radiances, is applied to IASI observations over mainland Australia in January and February of 2022. Validated against ERA5 and radiosonde observations, compared with the traditional <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>R</mi>\u0000 <mi>t</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${R}_{mathrm{t}}$</annotation>\u0000 </semantics></math>-based method, the <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>R</mi>\u0000 <mi>a</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${R}_{mathrm{a}}$</annotation>\u0000 </semantics></math>-based atmospheric profile retrievals show distinct improvements in boundary-layer humidity retrieval with at least 20% error reduction. This approach provides a new thought to enhance humidity retrievals from hyperspectral sounders and benefits other quantitative applications such as data assimilation.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL113404","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143555087","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":"Future Changes in Midwest Extreme Precipitation Depend on Storm Type","authors":"Tyler J. Mercurio, Christina M. Patricola","doi":"10.1029/2024GL113126","DOIUrl":"https://doi.org/10.1029/2024GL113126","url":null,"abstract":"<p>Midwestern U.S. extreme precipitation is associated with multiple storm types including mesoscale convective systems (MCSs) and/or training thunderstorms, tropical cyclone (TC) remnants, and winter storms. Anthropogenic warming is expected to increase climatological precipitation globally, however, there may be little correspondence with regional storm-based changes. Furthermore, uncertainty remains in precipitation-temperature scaling due to use of convective parameterization in most global models. In this study, we investigated historically impactful extreme precipitation events from multiple types of Midwest storms using the Weather Research and Forecasting model at convection-permitting resolution. We simulated five-member ensembles of historical hindcasts and experiments representing the storms in the future using the pseudo-global warming method. We found that future precipitation changes depend on storm type, with increases near Clausius-Clapeyron (CC) for winter storms, no consensus for MCSs and/or training thunderstorms, and sub-CC increases for TC remnants. This research highlights the importance of considering storm type in future extreme precipitation projections.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL113126","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143554453","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":"Climate-Induced Polar Motion: 1900–2100","authors":"Mostafa Kiani Shahvandi, Benedikt Soja","doi":"10.1029/2024GL113405","DOIUrl":"https://doi.org/10.1029/2024GL113405","url":null,"abstract":"<p>It has been demonstrated that the motion of the Earth's rotational pole with respect to the crust—termed polar motion—is increasingly influenced by barystatic processes, that is, continental-ocean mass redistribution due to melting of polar ice sheets, global glaciers, and variations in terrestrial water storage. However, how these processes might impact polar motion in the <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msup>\u0000 <mn>21</mn>\u0000 <mtext>st</mtext>\u0000 </msup>\u0000 </mrow>\u0000 <annotation> ${21}^{text{st}}$</annotation>\u0000 </semantics></math> century is not known. Here we investigate this problem under various climatic scenarios, namely, Representative Concentration Pathways (RCP) and Shared Socioeconomic Pathways. We show that the climate-induced polar motion is sensitive to the choice of climatic scenario; under the optimistic RCP2.6, the rotational pole might wander by <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>∼</mo>\u0000 </mrow>\u0000 <annotation> ${sim} $</annotation>\u0000 </semantics></math>12 m with respect to 1900, whereas under the pessimistic RCP8.5 by more than twice as much (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>∼</mo>\u0000 </mrow>\u0000 <annotation> ${sim} $</annotation>\u0000 </semantics></math>27 m). The most important contributor is the melting of polar ice sheets (Greenland and, to a lesser degree, Antarctica), followed by melting of global glaciers, and variations in terrestrial water storage.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL113405","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143554452","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}
Dandan Tao, Camille Li, Richard Davy, Shengping He, Thomas Spengler, Clio Michel, Andrea Rosendahl
{"title":"Arctic-Atlantic Cyclones: Variability in Thermodynamic Characteristics, Large-Scale Flow, and Local Impacts","authors":"Dandan Tao, Camille Li, Richard Davy, Shengping He, Thomas Spengler, Clio Michel, Andrea Rosendahl","doi":"10.1029/2024GL111769","DOIUrl":"https://doi.org/10.1029/2024GL111769","url":null,"abstract":"<p>Cyclones at polar latitudes of the Atlantic-Arctic corridor exhibit different thermodynamic characteristics. Midlatitude-origin cyclones, which make up about 14% of wintertime cyclones in the region, are generally warm and moist. The more numerous Arctic-origin cyclones display a wide range in the boundary-layer equivalent potential temperature <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>θ</mi>\u0000 <mi>e</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${theta }_{e}$</annotation>\u0000 </semantics></math> that depends on both temperature and moisture. This spread includes large positive and negative <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>θ</mi>\u0000 <mi>e</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${theta }_{e}$</annotation>\u0000 </semantics></math> anomalies, leading to weak signals in composite means. Warm/moist (high-<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>θ</mi>\u0000 <mi>e</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${theta }_{e}$</annotation>\u0000 </semantics></math>) cyclones at polar latitudes are associated with tilted and central jet regimes, steering cyclones of midlatitude-origin into the Barents region or preconditioning the environment for Arctic genesis. Conversely, cold/dry (low-<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>θ</mi>\u0000 <mi>e</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${theta }_{e}$</annotation>\u0000 </semantics></math>) Arctic-origin cyclones form under a jet stream positioned far south, characterized by frequent southern jet regimes. These new insights into the large variability of Barents cyclones have implications for our understanding of genesis mechanisms, cyclone development, and their effect on the climate of the polar regions.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL111769","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143554624","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}
Qian Yu, Zimeng Zhang, Piaopiao Ke, Jiale Chang, Han Li, Wenjia Wang, Lei Duan, Ronghua Kang, Lei Zhang, Yu Zhao
{"title":"Land-Air Exchanges of Various Gaseous Nitrogen Species in an Urban Wetland Based on In Situ Flux Observations","authors":"Qian Yu, Zimeng Zhang, Piaopiao Ke, Jiale Chang, Han Li, Wenjia Wang, Lei Duan, Ronghua Kang, Lei Zhang, Yu Zhao","doi":"10.1029/2024GL113265","DOIUrl":"10.1029/2024GL113265","url":null,"abstract":"<p>Wetlands are universally recognized as hotspots for nitrogen cycling and gaseous nitrogen emissions. In this study, the fluxes of nitric oxide (NO), nitrogen dioxide (NO<sub>2</sub>), ammonia (NH<sub>3</sub>), and nitrous oxide (N<sub>2</sub>O) were observed seasonally in the mud and waterfront plots of an urban wetland in eastern China using a dynamic flux chamber. The results revealed that the fluxes of NO, NO<sub>2</sub>, and NH<sub>3</sub> displayed a diurnal pattern of higher values during the day and lower values at night, which was opposite to that of N<sub>2</sub>O. The average annual emissions of NO, NH<sub>3</sub>, and N<sub>2</sub>O were 0.16 ± 0.04, 0.59 ± 0.03, and 8.81 ± 0.44 kg N ha<sup>−1</sup> yr<sup>−1</sup>, respectively. Conversely, NO<sub>2</sub> exhibited deposition, with an annual flux of 1.51 ± 0.03 kg N ha<sup>−1</sup> yr<sup>−1</sup>. Given the evolving area of urban wetlands, the emissions of gaseous nitrogen, particularly N<sub>2</sub>O, deserve substantial attention.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL113265","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143545915","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":"M\u0000 2\u0000 \u0000 \u0000 ${M}_{2}$\u0000 Seasonal Variability in Northwestern Europe: Characteristics and Drivers","authors":"Lucia Pineau-Guillou, Pascal Lazure","doi":"10.1029/2024GL112554","DOIUrl":"https://doi.org/10.1029/2024GL112554","url":null,"abstract":"<p>The <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>M</mi>\u0000 <mn>2</mn>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${M}_{2}$</annotation>\u0000 </semantics></math> tide displays large seasonal variability in Europe, particularly in the North Sea. The tide is there larger in summer than in winter. However, there is no consensus on the physical drivers leading to such large values, atmosphere circulation and stratification being two good candidates. We analyzed hourly sea level data from observations at 35 tide gauges in Europe. The amplitude of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>M</mi>\u0000 <mn>2</mn>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${M}_{2}$</annotation>\u0000 </semantics></math> seasonal cycle is the largest in the southern North Sea, reaching typically 4–6 cm. This cycle is well reproduced by a barotropic model, forced with the tidal potential and the atmosphere only. This suggests a minor role of the stratification. We show that large seasonal cycles in the southern North Sea are first due to gravitational nonlinear effects. The atmosphere also plays a role, but locally and in a smaller extent.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 5","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL112554","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143554625","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}