Earth and Space Science最新文献_第2页

Direct Observations of Surface Fluxes and Air-Sea Exchange Coefficients in Low Winds Using a Small Uncrewed Aircraft System 利用小型无人飞机系统直接观测低风条件下的地表通量和海气交换系数

IF 2.6 3区地球科学

Earth and Space Science Pub Date : 2025-08-22 DOI: 10.1029/2025EA004305

Christopher J. Deloach, Joshua B. Wadler, Guo Lin, Joseph J. Cione, Jun A. Zhang, Jack S. Elston, Maciej Z. Stachura

{"title":"Direct Observations of Surface Fluxes and Air-Sea Exchange Coefficients in Low Winds Using a Small Uncrewed Aircraft System","authors":"Christopher J. Deloach, Joshua B. Wadler, Guo Lin, Joseph J. Cione, Jun A. Zhang, Jack S. Elston, Maciej Z. Stachura","doi":"10.1029/2025EA004305","DOIUrl":"https://doi.org/10.1029/2025EA004305","url":null,"abstract":"In the marine boundary layer, the exchange of momentum, heat, and moisture occurs between the atmosphere and ocean. Since it is too dangerous for a crewed aircraft to fly close to the ocean surface to directly obtain these measurements, a sUAS (small Uncrewed Aircraft System) is one of the only viable options. On 24 March 2023 a Black Swift Technologies S0 sUAS was deployed from the NOAA P-3 on a calm clear day off the west coast of Florida. For 23 min at the end of the mission, the sUAS flew 8 straight line legs with an average length of 2.15 km, at roughly 10 m above the ocean surface, with wind speeds between 3.0 and 4.5 m s−1. For the first time over the open ocean using a sUAS, the 4-Hz wind and thermodynamic data was used to calculate surface momentum flux, sensible heat flux, and latent flux using both direct covariance methods and the bulk aerodynamic formulas. Since all the flux quantities can be found using both direct and indirect methods, we are able to calculate the exchange coefficients of momentum flux (CD), latent heat flux (CE), and sensible heat flux (CH) with results that are generally in good agreement with previous studies over the same wind speed range. This study demonstrates the ability of sUAS to measure air-sea interactions. Future intention is to use sUAS to obtain similar measurements in high wind events such as hurricanes which could better help understand hurricane intensification and improve model physics.","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 8","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2025EA004305","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144888436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Global and Regional Ionospheric Response to a Moderate Storm in South America and Antarctica Using a Multi-Instrumental Approach 多仪器方法对南美洲和南极洲一次中等风暴的全球和区域电离层响应

IF 2.6 3区地球科学

Earth and Space Science Pub Date : 2025-08-20 DOI: 10.1029/2025EA004281

Y. D. Melendi, M. Bravo, M. G. Molina, M. Paz, B. Urra, L. De Pasquale, D. E. Scipión, J. Namour, T. Duran, A. Zalizovski

{"title":"Global and Regional Ionospheric Response to a Moderate Storm in South America and Antarctica Using a Multi-Instrumental Approach","authors":"Y. D. Melendi, M. Bravo, M. G. Molina, M. Paz, B. Urra, L. De Pasquale, D. E. Scipión, J. Namour, T. Duran, A. Zalizovski","doi":"10.1029/2025EA004281","DOIUrl":"https://doi.org/10.1029/2025EA004281","url":null,"abstract":"In this study, we investigate the ionospheric disturbances caused by a moderate geomagnetic storm (maximum Kp = 6) occurring between 26th February and 1 March 2023. Ionospheric response for the coupling between the solar wind, magnetosphere, and ionosphere systems can be observed across various regions of the globe and it may vary according to the local/regional background ionospheric conditions. We analyzed space and ground-based instruments (e.g., ionosondes, total electron content, GUVI imager, incoherent scatter radar) covering from Antarctica to equatorial latitudes in South America. From a global perspective, we observed two ionospheric storms. The first, with a negative phase observed as a significant decrease (>30%) in the F2-layer critical frequency (foF2), occurred on February 27th at 01:00 UT. This negative phase storm was observed in all the considered regions, with the intensity progressively decreasing from higher to lower latitudes. It is worth mentioning that, for the Antarctic station, we consider the local regime of the Weddell Sea Anomaly. The second ionospheric storm occurred during the recovery phase of the geomagnetic storm on 28th February. In this last case, an enhancement above 30% in foF2 was observed only in the low-latitude station. Subsequently, the geomagnetic storm produced a super fountain effect at the Equatorial Ionization Anomaly resulting in the enhancement of foF2.","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 8","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2025EA004281","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144869909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","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 Analytical Model of Particle Impact Rate in Partially Dense Inclined Granular Flow Driven by Gravity 重力驱动部分致密倾斜颗粒流中颗粒撞击率的解析模型

IF 2.6 3区地球科学

Earth and Space Science Pub Date : 2025-08-20 DOI: 10.1029/2024EA003655

Zheng Chen, Jian Wang, Ming Luo, Dongpo Wang, Siming He

{"title":"An Analytical Model of Particle Impact Rate in Partially Dense Inclined Granular Flow Driven by Gravity","authors":"Zheng Chen, Jian Wang, Ming Luo, Dongpo Wang, Siming He","doi":"10.1029/2024EA003655","DOIUrl":"https://doi.org/10.1029/2024EA003655","url":null,"abstract":"High-frequency seismic waves are generated by inter-particle collisions during granular flows travel downslope. However, the accurate estimation of particle impact rates over granular layers remains a challenging issue. Here, controlled laboratory experiments were performed to investigate basal dynamic pressures triggered by the impact of particles on an instrumented plate mounted on an inclined chute bed. For a similar set-up, the discrete element method was utilized to determine granular-flow characteristics and the rate of inter-particle collisions. From a thermodynamic perspective, we present a novel model for calculating the impact rate over the granular-flow depth. Our estimates agree with the simulated results and previous laboratory measurements of acoustic power, suggesting that the impact rate follows a Gaussian distribution across the flow depth and the exponential attenuation factor of radiated acoustic power may correlate with thermodynamic parameters of granular material. These findings may help better understand the source of the high-frequency granular-flow signals.","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 8","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2024EA003655","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144869878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Error Analysis in Back-Stripping Procedure for Modeling Natural Subsidence: Application in the Po Delta Area (Northern Italy) 反剥离法模拟自然沉降的误差分析：在意大利北部波河三角洲地区的应用

IF 2.6 3区地球科学

Earth and Space Science Pub Date : 2025-08-16 DOI: 10.1029/2025EA004313

E. Vitagliano, C. D’Ambrogi, I. Spassiani, R. Di Maio

{"title":"Error Analysis in Back-Stripping Procedure for Modeling Natural Subsidence: Application in the Po Delta Area (Northern Italy)","authors":"E. Vitagliano, C. D’Ambrogi, I. Spassiani, R. Di Maio","doi":"10.1029/2025EA004313","DOIUrl":"https://doi.org/10.1029/2025EA004313","url":null,"abstract":"The back-stripping technique is widely used in geological modeling to quantify basin subsidence history, sedimentation rates, and tectonic subsidence. Recent applications involve reconstructing paleo-water depths, especially in oceanic and Arctic studies. Despite the availability of open-source Matlab codes based on this procedure, comprehensive investigations including errors from data acquisition remain lacking. Many studies address the errors related to model parameters, neglecting a systematic approach crucial for result accuracy. To enhance the reliability in subsidence rate calculations via back-stripping, we propose a method to analyze errors introduced during the pre-processing of input data. Our approach starts with a qualitative identification of key error sources and proceeds with a quantitative estimation of each of them, using appropriate mathematical techniques such as linear interpolation and combinatorics. The proposed method is applied to the Po Delta in northern Italy, a region historically influenced by anthropogenic and natural subsidence. Analyzing a 2D geological section characterized by thin Holocene sedimentary successions, we identified 12 error sources, grouped into four basic categories: geometry of the model layers, distribution of lithologies, petrophysical properties, and factors related to depositional environments and geodynamics. We then assessed the error ranges and their probability of occurrence. The results show that errors can vary significantly—from the meter to millimeter-scale—defining the magnitude and distribution of each error source along line, which is essential for accurately interpreting model results and assessing related uncertainties. The study also establishes a replicable workflow for future uncertainty management, contributing to enhance open-source tools based on the back-stripping procedure.","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 8","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2025EA004313","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144853766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dynamic Mode Decomposition of Geostrophically Balanced Motions From SWOT Cal/Val in the Separated Gulf Stream 分离湾流中SWOT Cal/Val地转平衡运动的动态模态分解

IF 2.6 3区地球科学

Earth and Space Science Pub Date : 2025-08-14 DOI: 10.1029/2024EA004079

Takaya Uchida, 内田貴也, Badarvada Yadidya, Karl E. Lapo, Xiaobiao Xu, Jeffrey J. Early, Brian K. Arbic, Dimitris Menemenlis, Luna Hiron, Eric P. Chassignet, Jay F. Shriver, Maarten C. Buijsman

{"title":"Dynamic Mode Decomposition of Geostrophically Balanced Motions From SWOT Cal/Val in the Separated Gulf Stream","authors":"Takaya Uchida, 内田貴也, Badarvada Yadidya, Karl E. Lapo, Xiaobiao Xu, Jeffrey J. Early, Brian K. Arbic, Dimitris Menemenlis, Luna Hiron, Eric P. Chassignet, Jay F. Shriver, Maarten C. Buijsman","doi":"10.1029/2024EA004079","DOIUrl":"https://doi.org/10.1029/2024EA004079","url":null,"abstract":"The decomposition of oceanic flow into its geostrophically balanced and unbalanced motions carries theoretical and practical significance for the oceanographic community. These two motions have distinct dynamical characteristics and affect the transport of tracers differently from one another. The launch of the Surface Water and Ocean Topography (SWOT) satellite provides a prime opportunity to diagnose the surface balanced and unbalanced motions on a global scale at an unprecedented spatial resolution. Here, we apply dynamic-mode decomposition (DMD), a linear-algebraic data-driven method, to tidally-forced idealized and realistic numerical simulations at submesoscale-permitting resolution and one-day-repeat SWOT observations of sea-surface height (SSH) in the Gulf Stream downstream of Cape Hatteras, a region commonly referred to as the separated Gulf Stream. DMD is able to separate out the spatial modes associated with sub-inertial periods from super-inertial periods. The sub-inertial modes of DMD can be used to extract geostrophically balanced motions from SSH fields, which have an imprint of internal gravity waves, so long as the data extends long enough in time. We utilize the statistical relation between relative vorticity and strain rate as the metric to gauge the extraction of geostrophy.","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 8","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2024EA004079","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144833315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Possible Linkage Between Barents–Kara Sea Ice Loss and Summer Precipitation Variability Over East Asia 巴伦支-喀拉海冰损失与东亚夏季降水变率之间的可能联系

IF 2.6 3区地球科学

Earth and Space Science Pub Date : 2025-08-14 DOI: 10.1029/2024EA004182

JingChao Yang, XuanWen Zhang, ZhenFeng Ma, XianYu Wang

{"title":"The Possible Linkage Between Barents–Kara Sea Ice Loss and Summer Precipitation Variability Over East Asia","authors":"JingChao Yang, XuanWen Zhang, ZhenFeng Ma, XianYu Wang","doi":"10.1029/2024EA004182","DOIUrl":"https://doi.org/10.1029/2024EA004182","url":null,"abstract":"Arctic sea ice (ASI) loss is a prominent indicator of climate system change, affecting mid to low latitudes weather and climate through intricate interactions and feedback processes. However, it remains unclear whether ASI loss significantly affects summer precipitation in East Asia at interannual scales. This analysis explores how the spring Barents–Kara (BK) sea ice anomaly is linked to summer precipitation interannual variability in East Asia (100°−122.5°E, 21°–36°N) since 1979 by using reanalysis data sets and Community Atmosphere Model 5.4 (CAM 5.4) simulation experiments. Both observational results and numerical simulation results indicate that the summer precipitation anomalies associated with the BK sea ice anomaly exhibit a dipole pattern over East Asia. In response to persistent BK sea ice loss from spring to summer, a Rossby wave is generated, which extends from the Arctic to the Northwest Pacific. This atmospheric circulation anomalies weakens the Northwest Pacific Subtropical High and strengthens the western Northwest Pacific summer monsoon (WNPSM). The intensified WNPSM not only inhibits the transport of subtropical water vapor from the South Asian monsoon to North China but also induces divergence of the lower troposphere in North China and convergence over South China. Consequently, summer rainfall increases in the southern part of East Asia and decreases in the northern region. Additionally, the CAM 5.4 simulation experiments successfully replicate key atmospheric responses to BK sea ice loss. The results indicate that the spring ASI may affect summer precipitation over East Asia independently of the interannual variability in the Arctic Oscillation and El Niño‒Southern Oscillation.","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 8","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2024EA004182","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144833301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

In-Depth Evaluation of Inversion of Coastal Tsunami Waveforms Utilizing Tsunami Source Constrained by Offshore Tsunami Waveforms From a Wide, Dense Observation Network: Application to the 2016 Mw 6.9 Off-Fukushima Earthquake, Japan 广域密集观测台网约束海啸震源反演沿海海啸波形的深度评价：在2016年日本福岛外海6.9 Mw地震中的应用

IF 2.6 3区地球科学

Earth and Space Science Pub Date : 2025-08-13 DOI: 10.1029/2024EA004043

Hiroaki Tsushima, Yutaka Hayashi, Takeyasu Yamamoto

{"title":"In-Depth Evaluation of Inversion of Coastal Tsunami Waveforms Utilizing Tsunami Source Constrained by Offshore Tsunami Waveforms From a Wide, Dense Observation Network: Application to the 2016 Mw 6.9 Off-Fukushima Earthquake, Japan","authors":"Hiroaki Tsushima, Yutaka Hayashi, Takeyasu Yamamoto","doi":"10.1029/2024EA004043","DOIUrl":"https://doi.org/10.1029/2024EA004043","url":null,"abstract":"The tsunami generated by the 2016 Mw 6.9 off-Fukushima earthquake, Japan, was recorded by offshore pressure gauges on a wide, dense ocean-bottom cable network, called S-net, as well as by offshore GPS buoys, coastal wave gauges and coastal tide gauges. In this work, source of the tsunami was inverted from the offshore tsunami waveforms and coastal tsunami waveforms independently, using the Green's functions based on linear long-wave theory. We found that inversion of the offshore waveforms returned robust results, more accurate and better resolved than those obtained from the coastal waveforms. Furthermore, nonlinear long-wave simulation using the offshore-data-inverted tsunami source, accurately reproduced the leading waves recorded at offshore and coastal stations. These results also demonstrated that tsunami nonlinearities are non-negligible, which is the main reason, together with weak constraints from the coastal waveforms, for the relative inaccuracy of the results of inversion from the coastal waveforms. This inaccuracy can be reduced by rearranging the conditions of inversion. Our analysis demonstrated that offshore tsunami waveforms from a wide, dense network are beneficial to deeply evaluate and improve inversion of coastal tsunami waveforms.","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 8","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2024EA004043","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144832376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Deep Argo Improves the Accuracy and Resolution of Ocean Bathymetry 深海Argo提高了海洋测深的精度和分辨率

IF 2.6 3区地球科学

Earth and Space Science Pub Date : 2025-08-13 DOI: 10.1029/2025EA004304

N. V. Zilberman, M. Scanderbeg, K. Balem, T. Schmitt, P. Weatherall, V. Thierry, E. Van Wijk, D. Sandwell

{"title":"Deep Argo Improves the Accuracy and Resolution of Ocean Bathymetry","authors":"N. V. Zilberman, M. Scanderbeg, K. Balem, T. Schmitt, P. Weatherall, V. Thierry, E. Van Wijk, D. Sandwell","doi":"10.1029/2025EA004304","DOIUrl":"https://doi.org/10.1029/2025EA004304","url":null,"abstract":"Ocean bathymetry plays an instrumental role in stirring ocean circulation and ocean mixing, shaping the transport of ocean heat, freshwater, oxygen, and carbon, influencing the propagation of tides and tsunamis, and controlling the dispersion of sediments, nutrients, and planktonic species. The dearth of direct ocean bathymetry measurements from shipboard echo sounders covering only 26% of the ocean floor calls for supplemental data. Satellites can provide bathymetry estimates in poorly-sampled regions, but intrinsic limitations of satellite measurements limit their ability to resolve features at horizontal scale <6 km (1/2 wavelength). Here, profile pressure and float descent rate from Deep Argo floats of the Deep Arvor and Deep SOLO float models were used to infer ∼14,000 ocean bathymetry measurements between 2014 and 2024. Our analysis indicates high consistency, 0.98 and 0.97 correlation coefficient, and small rms difference, 88 and 96 m, between multibeam sounding at 1,500–6,000 m depth and bathymetry measurements from Deep SOLO and Deep Arvor models respectively. The stronger agreement between Deep Argo-derived depths and multibeam data compared to altimetry is consistent with lower spatial uncertainties (<1.5 km for >77% of data coverage) and higher vertical accuracy of the Deep Argo data set (3.9–4.2 m at 4,000–6,000 m depth). The inclusion of the Deep Argo bathymetry in the general bathymetric chart of the ocean shows 50–200 m range improvement in the accuracy of altimetrically derived predicted depths.","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 8","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2025EA004304","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144832375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Robust Edge Detection for Structural Mapping Beneath the Aristarchus Plateau on the Moon Using Gravity Data 基于重力数据的月球阿里斯塔克斯高原结构制图鲁棒边缘检测

IF 2.6 3区地球科学

Earth and Space Science Pub Date : 2025-08-12 DOI: 10.1029/2025EA004379

Hanbing Ai, Qian Huang, Yunus Levent Ekinci, Ahmad Alvandi, Satya Narayan

{"title":"Robust Edge Detection for Structural Mapping Beneath the Aristarchus Plateau on the Moon Using Gravity Data","authors":"Hanbing Ai, Qian Huang, Yunus Levent Ekinci, Ahmad Alvandi, Satya Narayan","doi":"10.1029/2025EA004379","DOIUrl":"https://doi.org/10.1029/2025EA004379","url":null,"abstract":"Accurately detecting the edges of subsurface geological structures from potential field anomalies remains a fundamental challenge. We applied the HTHG (Hyperbolic tangent function with horizontal and vertical derivatives of Total Horizontal Derivative) method to enhance subtle details in lunar gravity anomalies, focusing on the Aristarchus region and its surroundings. Initial assessments were conducted on synthetic noise-free and noisy gravity data sets and compared against eleven representative edge detectors. In the noise-free data case, HTHG demonstrated superior performance over other detectors in terms of accuracy, resolution, sharpness, and amplitude balancing. However, similar to other approaches, its directional derivative calculations are highly susceptible to noise amplification. To address this challenge, we implemented various noise reduction techniques, including the β-VDR and MNLM methods. Notably, we also presented different methods for estimating the tuning parameters of the involved noise attenuation methods. HTHG, in conjunction with MNLM, demonstrated the most superior performance. We subsequently applied the HTHG operator to lunar gravity anomalies from the Aristarchus region. Our results were compared with the outputs of 2D inversion employing a mixed-weighted function, a correlation imaging algorithm, and 3D inversion enhanced by spectral analysis. Our findings indicate that the Aristarchus crater hosts a low-density subsurface mass. The outcomes of this study confirm the robust performance of the HTHG method in addressing edge detection challenges and underscore the necessity of integrating various methods, including edge detection, noise suppression, fast imaging, and inversion, to guarantee the interpretation reliability and advance our understanding about the internal architecture of the Moon.","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 8","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2025EA004379","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144814700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

SWOT Reveals Fine-Scale Balanced Motions Driving Near-Surface Currents and Dispersion in the Antarctic Circumpolar Current SWOT揭示了驱动南极环极流近地表流和弥散的精细尺度平衡运动

IF 2.6 3区地球科学

Earth and Space Science Pub Date : 2025-08-11 DOI: 10.1029/2025EA004248

Y.-T. Tranchant, B. Legresy, A. Foppert, B. Pena-Molino, H. Phillips

{"title":"SWOT Reveals Fine-Scale Balanced Motions Driving Near-Surface Currents and Dispersion in the Antarctic Circumpolar Current","authors":"Y.-T. Tranchant, B. Legresy, A. Foppert, B. Pena-Molino, H. Phillips","doi":"10.1029/2025EA004248","DOIUrl":"https://doi.org/10.1029/2025EA004248","url":null,"abstract":"The Antarctic Circumpolar Current (ACC) is a hotspot for the generation of small-scale motions that have a key role in cross-frontal exchanges. We present the first analysis of surface currents in the ACC derived from high-resolution sea surface height (SSH) fields provided by the new Surface Water and Ocean Topography (SWOT) satellite. To mitigate the impact of noise and unbalanced SSH, we introduce a two-dimensional fitting kernel method for deriving geostrophic and cyclogeostrophic velocities at different lengthscales. These velocity estimates are evaluated against the low-pass filtered component (<math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>></mo>\u0000 </mrow>\u0000 <annotation> ${ >} $</annotation>\u0000 </semantics></math>1 day) of trajectories from 21 surface drifters that passed through the ACC meander. The SSH is found to be balanced and appropriate for inferring surface velocities at scales as small as 10 km, with an 18 km length scale identified as a trade-off between suppressing residual unbalanced waves and preserving finer-scale balanced signals in SWOT denoised SSH. At this scale, the geostrophic approximation becomes inaccurate, and higher-order terms in the momentum balance contribute up to 20% of the observed drifter velocities. Finally, distance-averaged pair statistics calculated from drifter pairs and virtual particles reveal that SWOT accurately captures dispersion properties over the 10–200 km range, providing observational evidence of the dominant role of balanced motions in particle dispersion within this range. By capturing balanced dynamics with unprecedented accuracy, SWOT SSH offers new opportunities to understand the impact of small scales on tracer exchange in the ACC and the Southern Ocean more broadly.","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 8","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2025EA004248","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144811200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0