Geophysical Research Letters最新文献

{"title":"Topography Dominates the Hemispheric Asymmetry of Stratospheric Sudden Warmings","authors":"Siming Liu,&nbsp;Tiffany Shaw,&nbsp;Chaim I. Garfinkel","doi":"10.1029/2024GL113051","DOIUrl":"https://doi.org/10.1029/2024GL113051","url":null,"abstract":"<p>Stratospheric sudden warmings (SSWs) predominantly occur in the Northern Hemisphere (NH) with only 1 major event recorded in the Southern Hemisphere in the satellite era. Investigating factors that contribute to this asymmetry can help to reveal the cause of SSWs and lead to improved forecasts. Here we use climate model simulations to investigate the impact of boundary conditions (topography and ocean circulation) on the hemispheric asymmetry. Flattening topography eliminates NH SSWs, while removing the ocean meridional overturning circulation reduces their frequency by half. The SSW response to boundary conditions is controlled by the hemispheric asymmetry of eddy heat flux. The reduction is driven by a decrease in amplitude of both eddy meridional wind and eddy temperature, as well as an increase in the cosine of the difference between their phases. The results suggest boundary conditions play an important role in shaping SSWs, especially topographic forcing, but that the boundary condition interactions are nonlinear.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 8","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL113051","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143861802","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":"Probabilistic, Multi-Sensor Eruption Forecasting","authors":"Y. Behr,&nbsp;A. Christophersen,&nbsp;C. Miller","doi":"10.1029/2024GL112029","DOIUrl":"https://doi.org/10.1029/2024GL112029","url":null,"abstract":"<p>We developed an eruption forecasting model using data from multiple sensors or data streams with the Bayesian network method. The model generates probabilistic forecasts that are interpretable and resilient against sensor outage. We applied the model at Whakaari/White Island, an andesite island volcano off the coast of New Zealand, using seismic tremor recordings, earthquake rate, and CO₂, SO₂, and H₂S emission rates. At Whakaari/White Island, our model shows increases in eruption probability months to weeks prior to the three explosive eruptions that were recorded between 2013 and 2019. Our model outperforms the use of any of the data sets alone as an indicator for impending eruptions. Although developed for Whakaari/White Island, our model can be easily adapted to other volcanoes, complementing existing forecasting methods that rely on single data streams.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 8","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL112029","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143861803","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":"Characterization of Convection and Rainfall Off the Pacific Coast of Colombia Using Airborne Radar and Dropsonde Data","authors":"D. J. Raymond,&nbsp;Ž. Stone","doi":"10.1029/2024GL114186","DOIUrl":"https://doi.org/10.1029/2024GL114186","url":null,"abstract":"<p>The Organization of Tropical East Pacific Convection project used dropsondes deployed from high altitude and a downward-pointing W-band Doppler radar to document the characteristics of mesoscale convective systems (MCSs) located over the Pacific coastal waters of Colombia. MCSs dominated by ice crystal aggregates above the freezing level rather than graupel, as shown by the radar, are generally thought to indicate decaying stratiform rain systems with only light rain. However, dropsonde grids showed a broader range of MCS types in this category, some with shallow convection producing intense rainfall. The radar had difficulty in distinguishing between different types of aggregate-dominated MCSs.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 8","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL114186","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143861806","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":"Integrating Top-Down Energetic Constraints With Bottom-Up Process-Based Constraints for More Accurate Projections of Future Warming","authors":"D. Watson-Parris","doi":"10.1029/2024GL114269","DOIUrl":"https://doi.org/10.1029/2024GL114269","url":null,"abstract":"<p>The quantification of aerosol-induced radiative forcing and cloud feedbacks remains a significant challenge in climate modeling, primarily due to the complex interplay of aerosol and clouds in a warming world. Traditional approaches often rely on either bottom-up process-based models, difficult to constrain against present-day observations, or top-down methods that lack the ability to capture the underlying processes accurately. Here, we present an approach that combines both bottom-up process-based constraints and top-down energetic constraints of aerosol forcing and cloud feedbacks simultaneously to achieve a more comprehensive understanding of aerosol impacts on clouds and the climate. Applying the new method to the Community Atmosphere Model v6, we infer narrower parameter ranges for key process parameters, a reduced effective radiative forcing of −1.08 [−1.29–−0.77] Wm⁻², and hence 66% more precise future projections.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 8","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL114269","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143861961","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":"Previously Neglected Effects of Strong Horizontal Winds on Raindrop Collisions in Tropical Cyclones","authors":"Lin Deng,&nbsp;Xuwei Bao,&nbsp;Istvan Geresdi,&nbsp;Lulin Xue,&nbsp;Wei Huang,&nbsp;Yang Zhao,&nbsp;Wanchen Wu,&nbsp;Tiantian Li","doi":"10.1029/2025GL115535","DOIUrl":"https://doi.org/10.1029/2025GL115535","url":null,"abstract":"<p>Persistent strong winds are a common feature within the near-surface layer of tropical cyclones, which can induce pronounced horizontal motion as raindrops descend. However, current state-of-art microphysics schemes typically only consider the vertical motion of raindrops, ultimately failing to accurately simulate the collisional outcomes of raindrops and the associated raindrop size distributions (RSDs) under strong winds. For instance, the original bin microphysics scheme was unable to successfully reproduced the evolution of RSDs with decreasing height, as measured from the multi-layer observations during the landfall of Typhoon Pakhar (2017). Thus, this study introduces a modified bin microphysics scheme that incorporates the influence of horizontal wind speeds, vertical wind shear and smaller-scale turbulence on the total movement velocity (including horizontal and vertical components) of raindrops, and consequently on their collisional outcomes. This modification demonstrates a remarkable improvement in the representation of the intrinsic variation in RSDs with decreasing height under strong-wind conditions.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 8","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025GL115535","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143857092","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":"Association of Relativistic Electron Microbursts Duration With Chorus Wave Properties","authors":"Jiabei He,&nbsp;Lunjin Chen,&nbsp;Zhiyang Xia,&nbsp;Mykhaylo Shumko,&nbsp;Lauren Blum","doi":"10.1029/2024GL113694","DOIUrl":"10.1029/2024GL113694","url":null,"abstract":"<p>Relativistic electron microbursts are correlated with resonant scattering by whistler-mode chorus waves. Here, we use chorus wave properties obtained from Van Allen Probe A to calculate the duration of relativistic microbursts. A detailed quantitative comparison between observed and calculated microburst durations shows consistent ranges and similar correlations with <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>L</mi>\u0000 </mrow>\u0000 <annotation> $L$</annotation>\u0000 </semantics></math> shell and magnetic local time (MLT). The most apparent trend is in MLT: microburst duration increases from midnight through the dawn sector but decreases after noon. These results highlight the primary role of chorus waves in driving microbursts. Furthermore, we build a constraint on the upper magnetic latitude boundary <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mfenced>\u0000 <msub>\u0000 <mi>λ</mi>\u0000 <mn>2</mn>\u0000 </msub>\u0000 </mfenced>\u0000 </mrow>\u0000 <annotation> $left({lambda }_{2}right)$</annotation>\u0000 </semantics></math> of chorus waves that can induce 1 MeV microbursts. The constraint is dependent on MLT. On the dayside, the optimal <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>λ</mi>\u0000 <mn>2</mn>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${lambda }_{2}$</annotation>\u0000 </semantics></math> typically exceeds <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>36</mn>\u0000 <mo>°</mo>\u0000 </mrow>\u0000 <annotation> $36{}^{circ}$</annotation>\u0000 </semantics></math>, which is higher than on the nightside, suggesting ducted chorus propagation dominates. Chorus waves with higher <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>λ</mi>\u0000 <mn>2</mn>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${lambda }_{2}$</annotation>\u0000 </semantics></math> are generally more effective in triggering relativistic microbursts.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 8","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL113694","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143858021","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":"CO2 Release During Soil Rewetting Shapes the Seasonal Carbon Dynamics in South American Temperate Region","authors":"Sanam N. Vardag,&nbsp;Eva-Marie Metz,&nbsp;Lukas Artelt,&nbsp;Sourish Basu,&nbsp;André Butz","doi":"10.1029/2024GL111725","DOIUrl":"10.1029/2024GL111725","url":null,"abstract":"<p>Processes driving the terrestrial carbon fluxes in the South American Temperate (SAT) region are not well understood due to limited availability of in situ and flux tower measurements. This study leverages atmospheric CO₂ measurements by the Greenhouse Gases Observing Satellite to additionally constrain net carbon fluxes in the SAT region. By identifying Dynamic Global Vegetation Models that closely align with observational data, we pinpoint the processes driving the seasonal land-atmosphere CO₂ exchange. We reveal that the onset of rainfall triggers an early increase in heterotrophic respiration while autotrophic respiration and gross primary production are delayed leading to an increase in net ecosystem exchange in September to October. Our findings suggest that soil rewetting processes in semi-arid areas dominate seasonal carbon dynamics and need to be accurately represented in global carbon cycle models to improve the global carbon budget.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 8","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL111725","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143858022","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":"Stream Nutrient Load and Concentration Estimation From Minimal Measurements","authors":"Wasif Bin Mamoon,&nbsp;Kun Zhang,&nbsp;Mitul Luhar,&nbsp;Anthony J. Parolari","doi":"10.1029/2025GL114935","DOIUrl":"10.1029/2025GL114935","url":null,"abstract":"<p>High-resolution measurements of nutrients in rivers are vital to assess water quality and catchment material balances. Yet, such measurements are often cost-prohibitive. To improve sampling efficiency, data-driven sparse sensing (DSS) is proposed to recover high-resolution nutrient time-series from sparse flow and concentration measurements. DSS leverages dimension-reduction to identify basis functions that optimally represent available data, and analyzes these basis functions to identify optimal times and locations for future measurements. A model trained on high-resolution flow and concentration measurements from few locations accurately reconstructed nutrient concentration time-series and annual loads at target sites spanning the Midwest region of the US. Optimal sampling times occurred in spring, while sampling locations were distributed across catchment area and flow. Sparse measurements (20–80 per year) at optimal sampling times and locations were sufficient to accurately estimate nutrient concentrations and loads (error &lt;±2% for NOx; &lt;±9% for total phosphorus). DSS promises to enable cost-effective water quality monitoring.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 8","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025GL114935","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143857803","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":"Severe Distortion of the Apparent Resistivity Induced by the Super Geomagnetic Storm in May 2024","authors":"Xin Zhang,&nbsp;Tao Xie,&nbsp;Qing Ye,&nbsp;Liangjun Yan,&nbsp;Xiaoping Wu","doi":"10.1029/2025GL115104","DOIUrl":"https://doi.org/10.1029/2025GL115104","url":null,"abstract":"<p>The potential hazard of geomagnetically induced current (GIC) in metallic pipelines caused by space weather events is a widely discussed topic. On 10–11 May 2024, a super geomagnetic storm with Kp = 9 comparable to the Halloween event in 2003 occurred. The storm induced GIC caused severe distortion in apparent resistivity is a novel phenomenon. Here, we studied an apparent resistivity observation network of China, which was severely affected by the GIC. The impact reached over 15 times the static daily variation, inducing the apparent resistivity values to be significantly distorted, with 35 of 70 stations observing resistivity changes over 1%. Additionally, some stereo observations had significant responses and appeared time-delay pattern reaching 24 hr. The induced polarization effect may involve and release the charges slowly, then delay the response pattern of apparent resistivity under the super storm. Effectively it is the first academic report of the GIC effect in apparent resistivity.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 8","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025GL115104","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143857091","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":"Stratospheric Water Vapor Beyond NASA's Aura MLS: Assimilating SAGE III/ISS Profiles for a Continued Climate Record","authors":"K. Emma Knowland,&nbsp;Pamela A. Wales,&nbsp;Krzysztof Wargan,&nbsp;Brad Weir,&nbsp;Steven Pawson,&nbsp;Robert Damadeo,&nbsp;David Flittner","doi":"10.1029/2024GL112610","DOIUrl":"10.1029/2024GL112610","url":null,"abstract":"<p>Stratospheric water vapor (SWV) is a greenhouse gas that has an important, yet uncertain, impact on the Earth's climate through its radiative effect and feedback. As the climate changes, it is thus critical to monitor and understand changes in SWV. NASA's Microwave Limb Sounder (MLS) aboard the Aura satellite has observed SWV since 2004 but is reaching end of life. The Stratospheric Aerosol and Gas Experiment (SAGE) missions observe SWV as well, with the SAGE III instrument operating on the International Space Station (ISS) since 2017. We use the constituent data assimilation capabilities of NASA's Goddard Earth Observing System (GEOS) to demonstrate that the up to 30 SAGE III/ISS profiles each day provide a useful constraint over the observed midlatitudes and tropics. We conclude that by assimilating SAGE III/ISS SWV into GEOS we can largely continue to monitor SWV after Aura MLS.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 8","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL112610","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143857684","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}