Earth and Space Science最新文献

{"title":"Structural and Process Drivers of Spring Surface Albedo Feedback Uncertainty and Its Future Evolution Across Northern Hemisphere Extratropical Lands","authors":"Linfei Yu,&nbsp;Guoyong Leng","doi":"10.1029/2026EA005209","DOIUrl":"https://doi.org/10.1029/2026EA005209","url":null,"abstract":"<p>Surface albedo feedback (SAF) strongly amplifies spring warming across Northern Hemisphere extratropical land (&gt;30°N), yet Earth system models (ESMs) show substantial inter-model spread. Here we quantify spring (March–May) mean SAF and decompose its uncertainty into snow-cover dynamics (SNC) and temperature-driven snow albedo modulation (TEM) components across 34 ESMs from Coupled Model Intercomparison Project Phase 6 (CMIP6). Historical (1985–2014) multi-model mean SAF is 1.68 W m⁻² K⁻¹ (range 0.93–2.69 W m⁻² K⁻¹). In late-century (2070–2099), SAF shows a slight decline, with multi-model means ranging from 1.51 W m⁻² K⁻¹ to 1.62 W m⁻² K⁻¹ and inter-model spreads of 0.94–2.82 W m⁻² K⁻¹ across the four SSP scenarios. Relative uncertainty, quantified by the coefficient of variation, stays remarkably stable at 26.8%–30.6%. Spatially, high-latitude persistent snow regions exhibit the strongest SAF and uncertainty, where TEM dominates (contributing 59.6%–62.0%). In contrast, transitional mid-latitude zones are mainly controlled by SNC (contributing 40%–60%). Random Forest and SHAP (SHapley Additive exPlanations) analyses reveal that SNC uncertainty arises primarily from near-surface air temperature and snow structural variability, whereas TEM uncertainty is driven by snow depth, black carbon wet/dry deposition, and surface energy processes. Under high-emission scenarios, thermodynamic forcing and snow depth variability increasingly dominate both components, producing pronounced nonlinear responses and a regime shift in uncertainty sources. These findings demonstrate that spring SAF uncertainty is process-dependent, spatially heterogeneous, and dynamically reorganized by warming intensity. Improving snow optical parameterization and aerosol–snow interactions is therefore critical to reduce uncertainty in extratropical climate projections.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"13 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026EA005209","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148615812","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}

{"title":"Machine Learning-Based Swath Bias Correction for OCO-3 Snapshot Area Mapping Mode Observations","authors":"Steffen Mauceri,&nbsp;Robert R. Nelson,&nbsp;Christopher W. O’Dell,&nbsp;Thomas E. Taylor,&nbsp;Matthäus Kiel,&nbsp;Steven Massie,&nbsp;Vivienne H. Payne,&nbsp;Abhishek Chatterjee","doi":"10.1029/2025EA004853","DOIUrl":"https://doi.org/10.1029/2025EA004853","url":null,"abstract":"<p>Space-based monitoring of urban carbon dioxide (CO₂) emissions is essential for climate policy, but systematic measurement biases can compromise emission quantification accuracy. NASA's Orbiting Carbon Observatory-3 (OCO-3) provides unique Snapshot Area Mapping (SAM) mode observations that can capture city-scale CO₂ plumes in single overpasses, yet some SAMs exhibit swath-based XCO₂ biases of 1–3 ppm that can mask or artificially enhance true emission signals. Here, we develop a machine learning framework to identify and correct these artifacts while preserving genuine atmospheric CO₂ variations. We trained a random forest classifier on 1,723 manually labeled SAMs spanning August 2019 to February 2025 to distinguish scenes requiring bias correction from those with legitimate spatial gradients in XCO₂. The model uses five key diagnostic features identified through systematic feature selection: inter-swath XCO₂ discontinuity, scene homogeneity, coarse- and fine-mode aerosol optical depths, and spectral alignment corrections. A median-alignment algorithm then removes detected biases by adjusting swath-level offsets while conserving total column CO₂. The classifier achieves a precision and recall of 79% and 63%, respectively, prioritizing the avoidance of false corrections that could otherwise remove true atmospheric signals. Applied to the complete OCO-3 SAM record, consisting of 19,839 unique SAMs, we estimate that approximately 9% have an identifiable swath bias. This work addresses a critical OCO-3 data quality issue that has hindered the operational use of OCO-3 SAMs for urban fossil fuel emissions monitoring. The proposed correction framework enhances OCO-3 data reliability for use in updating emission inventories and provides methodological insights for future greenhouse gas satellite missions.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"13 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025EA004853","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148615743","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}

{"title":"Antarctic Snowfall Patterns and Trends: A Regional Analysis Across Multiple Data Sets","authors":"Valerie Song,&nbsp;Yuekui Yang,&nbsp;Surendra Bhatta","doi":"10.1029/2025EA004834","DOIUrl":"https://doi.org/10.1029/2025EA004834","url":null,"abstract":"<p>Snowfall is the dominant positive component of the Antarctic surface mass balance (SMB) and a key factor regulating global sea level. However, substantial uncertainty remains in its spatial distribution and long-term variability due to sparse in situ observations and retrieval challenges over polar ice sheets. This study evaluates Antarctic snowfall patterns and trends using multiple data sets, including satellite-based products (Global Precipitation Climatology Project (GPCP) V3.3, IMERG V7), atmospheric reanalyzes (MERRA-2, ERA5), and CloudSat radar retrievals as an observational benchmark. To better examine spatial heterogeneity and regional variability, the Antarctic domain is subdivided into six regions: East and West Antarctica, coastal and inland zones, the high plateau (elevation ≥2,250 m), and lowland areas (&lt;2,250 m). CloudSat comparisons show that GPCP, MERRA-2, and ERA5 reproduce the large-scale spatial and seasonal snowfall patterns, whereas IMERG severely underestimates accumulation. During 2000–2024, GPCP and ERA5 both exhibit statistically significant positive snowfall trends, while MERRA-2 shows no statistically significant change. Regional and grid-point analyses reveal coherent positive trends across East Antarctica, and localized coastal regions. Overall, the results indicate a modest but spatially consistent increase in Antarctic snowfall during 2000–2024, in line with enhanced atmospheric moisture transport under a warming climate, with implications for understanding the evolving Antarctic SMB and its contribution to sea-level change.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"13 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025EA004834","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148615744","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}

{"title":"Strategic Micro-Awards Train the Next Generation and Grow a Cross-Disciplinary Scientific Community: The AGeS Program Example","authors":"R. M. Flowers,&nbsp;J. R. Arrowsmith","doi":"10.1029/2025EA004884","DOIUrl":"https://doi.org/10.1029/2025EA004884","url":null,"abstract":"<p>Strategic micro-grant programs have tremendous scientific and educational value. Such programs are cost-effective and can be leveraged to support student training and incentivize new cross-disciplinary science. Over the last 12 years, the AGeS (Advancing Geochronology Science, Spaces, and Systems) initiative developed three proposal-driven micro-award programs ($8-$18k awards) to better train the future scientific workforce and build a web of new collaborative relationships across the Earth sciences. AGeS grew to include 72 geochronology labs and &gt;120 geochronologists, ran 12 proposal cycles, saw 540 submitted proposals, made 169 awards, distributed &gt;$1M in funding to 140 graduate students for collaborative research in labs, generated numerous publications from new scientific partnerships, held dozens of steering and review committee meetings, ran four workshops, and involved hundreds across the Earth sciences in research, training, review, and governance activities. The AGeS program was terminated in April 2025 during the U.S. federal transition, when the National Science Foundation (NSF) rescinded support that had been allocated for 100 more AGeS micro-awards. Initiatives like AGeS are crucial for training and building the networks of the next generation of scientists, growing a scientific community that can work together across traditionally siloed fields. A cross-disciplinary and highly-trained community of Earth scientists is vital for solving the most pressing Earth science problems of our time, from critical mineral needs to geohazards to climate change.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"13 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025EA004884","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148615479","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}

{"title":"Topographic and Geological Factors Affecting Martian Transverse Aeolian Ridges: A Multi-Source Remote Sensing Analysis of Morphology and Local Sediment Provenance","authors":"Jie Zhang,&nbsp;Sicong Liu,&nbsp;Xiaohua Tong,&nbsp;Paolo Gamba,&nbsp;Huan Xie,&nbsp;Yonggang Xiong,&nbsp;Jiang Long,&nbsp;Kaiyue Luo,&nbsp;Kecheng Du","doi":"10.1029/2026EA005080","DOIUrl":"https://doi.org/10.1029/2026EA005080","url":null,"abstract":"<p>Transverse aeolian ridges (TARs) on Mars exhibit distinct characteristics relative to other aeolian features, yet their formation and evolutionary mechanisms remain unclear. A comprehensive investigation of TAR's distribution, morphology, composition, and environmental influences is critical for advancing our understanding of their development and implications for Martian climatic history. This research leverages multi-source orbital remote sensing data to explore TARs across various Martian regions and quantify the hierarchical controls of regional environment on TAR characteristics. High-resolution orbital images were employed to extract and quantify TAR parameters (area ratio, width, and length) for 33,946 identified TARs across six study areas. Results demonstrated a strong positive correlation (<i>r</i> &gt; 0.9) between TAR area ratio and elevation/roughness, with a weaker correlation (<i>r</i> &lt; 0.5) to slope, particularly when the area ratio exceeds 0.6, indicating that steep slopes act as a limiting threshold that inhibits TAR clustering. Morphologically, TAR width exhibits stronger linearity with topography (<i>r</i> &gt; 0.759) than length (<i>r</i> &gt; 0.588); the correlation for length diminishes notably as length increases, suggesting that topographic obstacles (roughness) physically fragment TAR continuity. Spectral analyses, validated by laboratory standard spectra (RELAB), identify diverse minerals (including olivine, hematite, and chlorides) that match local bedrock compositions. These findings confirm the predominantly local provenance of TAR sediments and highlight that regional variations in TAR characteristics are intrinsically driven by distinct geological evolution histories.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"13 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026EA005080","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148753716","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}

{"title":"Howard University Beltsville Campus Ozonesonde Record: Data Homogenization and Uncertainties","authors":"Joshua A. D. Richards,&nbsp;Ryan M. Stauffer,&nbsp;Debra E. Kollonige,&nbsp;Anne M. Thompson,&nbsp;Belay Demoz,&nbsp;Ricardo K. Sakai,&nbsp;Adrian Flores","doi":"10.1029/2026EA005120","DOIUrl":"https://doi.org/10.1029/2026EA005120","url":null,"abstract":"<p>Ensuring the quality and consistency of multidecadal electrochemical concentration cell (ECC) ozonesonde records is essential because changes in sonde instrumentation, sensing solutions, operating procedures, and data-processing methods can introduce biases that compromise their suitability for trend analyses and model/satellite evaluation. Following best practices outlined by global ozonesonde experts through the Assessment of Standard Operating Procedures for Ozonesondes 2.0 (ASOPOS 2.0), we summarize the “homogenization” of the Howard University Beltsville Campus (HUBC; 39.054°N, 76.877°W, 53 m elevation) ozonesonde data set from 2006 to 2022. The HUBC station lies in an urbanized Mid-Atlantic region north of Washington, DC, serving as a prototype for most of the US east coast where mountains, megacities, the coastal plain, and large bodies of water yield complex transport patterns and challenges for model and satellite ozone estimations. We present an overview of the data reprocessing methods, their application to the HUBC time-series, and evaluate the homogenized HUBC data set relative to the original records. Total column ozone (TCO) from the reprocessed record, with uncertainties, is compared to TCO from satellite and a nearby Brewer spectrometer. The results of the homogenization: (a) sonde total column ozone increases by up to +3%; (b) stratospheric negative biases in the Aura MLS-sonde comparison improve from a mean of −3.2% before homogenization to −1.8%; (c) Total column ozone comparisons of both satellite-sonde and Brewer-sonde display similar improved percent differences with a decreased variance and reveal satellite sensitivity issues in capturing lower-tropospheric measurements; (d) sonde ozone uncertainties fall below 7% throughout profile, regardless of season.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"13 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026EA005120","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148754252","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}

{"title":"Sensitivity of Physical Schemes in WRF Simulations on the Track and Intensity of Landfalling Tropical Cyclones in East China","authors":"Yuemin Fan,&nbsp;Zhenshou Yu,&nbsp;Jianing Feng","doi":"10.1029/2026EA005095","DOIUrl":"https://doi.org/10.1029/2026EA005095","url":null,"abstract":"<p>The selection of appropriate physical parameterization schemes (PPSs) is crucial for improving the simulation accuracy of numerical weather prediction models. This study evaluates the sensitivity of landfalling Tropical Cyclones (TCs), to PPSs in the Weather Research and Forecasting model. We are focusing on the TCs of Lekima (2019), Hagupit (2020), and In-Fa (2021). For each of the three TC cases, 42 sensitivity experiments are conducted, resulting in a total of 126 simulations across three categories, which are planetary boundary layer parameterization scheme (PBLPS), cumulus convection parameterization scheme (CCPS), and cloud microphysics parameterization scheme (CMPS). Among the three categories, the PBLPS category achieves the best simulation on TC intensity, including landfall intensity. Both of TC track and intensity are the most sensitive to CMPS, and CMPS impacts TC track more during the post-landfall stage than pre-landfall stage. TC track is insensitive to PBLPS, especially during the post-landfall stage, because of the influence of large-scale forcing. PBLPS category has the smallest average track error. Furthermore, both landfall position and intensity have local sensitive to PBLPS. On average within the categories, the CMPS category shows the best performance in the simulation of TCs landfall position, while the PBLPS category has the minimum error in the simulation of TCs landfall intensity. Finally, the optimal schemes for TC track and intensity can respectively provide reference for the simulation of landfalling TCs in the future.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"13 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026EA005095","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148467242","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}

{"title":"Intensifying Climate Extremes Over the Tibetan Plateau: Past–Future Changes and Implications for Railway Infrastructure","authors":"Bohao Li,&nbsp;Kai Liu,&nbsp;Yan Tong,&nbsp;Wanying Zhang,&nbsp;Yanfang Wang,&nbsp;Linmei Zhuang,&nbsp;Yichen Yan,&nbsp;Weihua Zhu,&nbsp;Yuanhang Yang,&nbsp;Ming Wang","doi":"10.1029/2026EA005096","DOIUrl":"https://doi.org/10.1029/2026EA005096","url":null,"abstract":"<p>Climate extremes over the Tibetan Plateau (TP) are intensifying and can threaten high-altitude railways by altering permafrost stability, freeze–thaw regimes, drainage pressure, and hydro-geomorphic hazards, yet their evolution for railways remains insufficiently quantified. Using CN05.1 observations (1961–2022) and an evaluated NEX-GDDP-CMIP6 ensemble, we quantified historical and future (2025–2100) changes in temperature- and precipitation-related extremes across the TP and its major railways. Observations show that cold extremes weaken and warm extremes intensify across the TP: cold nights (TN10p) decrease by 0.29% yr⁻¹, and warm spell duration index (WSDI) increases by 0.35 days yr⁻¹. Precipitation extremes increase heterogeneously, mainly in the southern and eastern TP. Under SSP5-8.5, fixed-baseline temperature indices indicate a pronounced thermal-regime shift: warm nights (TN90p) and warm days (TX90p) approach 80% by 2071–2100, WSDI reaches 255 days, and cold extremes approach near-zero levels; precipitation-related indices also intensify, with the strongest increases concentrated in the southern TP. Lower-emission scenarios exhibit the same directional changes but with reduced magnitudes. Corridor differences are projected to emerge: the Xinjiang–Xizang Railway remains colder in absolute temperature extremes than the Qinghai–Xizang Railway but shows stronger precipitation intensification. By the 2090s under SSP5-8.5, the Xinjiang–Xizang Railway remains 2°C colder in annual maximum daily maximum temperature (TXx), but annual maximum 5-day precipitation (RX5day) and annual total wet-day precipitation (PRCPTOT) increase to 63.7 and 561.7 mm, approximately 1.4 and 1.7 times higher, respectively. These results identify priorities for corridor-specific permafrost thermal protection, drainage design, slope-hazard mitigation, and long-term adaptation.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"13 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026EA005096","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148467184","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}

{"title":"Correlative X-Ray and Neutron Tomography of Microbial Biosignatures: Perspectives for Mars Sample Return","authors":"Sylvia Olewinski,&nbsp;Imran A. Rahman,&nbsp;Anna Fedrigo,&nbsp;Peta A. Hayes,&nbsp;Caroline L. Smith,&nbsp;Keyron Hickman-Lewis","doi":"10.1029/2025EA004536","DOIUrl":"https://doi.org/10.1029/2025EA004536","url":null,"abstract":"<p>Mars Sample Return (MSR) is the next major frontier in Mars exploration, through which advanced laboratory instrumentation will be used to study Martian samples and answer key questions surrounding Mars' planetary evolution and astrobiology. Non-destructive, high-resolution imaging will be critical for preliminary MSR analyses. Among the many functional analogs appropriate for biosignature detection training, Precambrian microbialites are considered uniquely representative of microbial ecosystems considered plausible on Noachian–Hesperian Mars. Here, we assessed the feasibility of interpreting coupled tomographic data sets using mature (∼1 Ga) biosignature-bearing stromatolites from the Mbuji-Mayi Supergroup (DR Congo). Samples were imaged using X-ray μCT and neutron tomography (NT) to obtain high-resolution 3D visualizations, which were evaluated for complementarity. By correlating tomographic data from both techniques, we provide spatially resolved 3D insights into compositional variations, including the presence of organic-bearing morphological biosignatures, while resolving complex phase relationships. Although X-ray μCT offers higher resolution insights into density variations and rock microstructure, our novel usage of NT to analyze stromatolites provides effective characterization of light element-dominated phases. The accuracy of textural conclusions based on tomographic data are evaluated using optical microscopy and the compositional characteristics are verified using Scanning Electron Microscopy With Energy-Dispersive X-Ray Spectroscopy elemental mapping. Our results highlight the utility of correlated X-ray and NT during the preliminary stages of MSR sample analysis and support the integration of these techniques into workflows in the MSR Sample Receiving Facility. Uniting data sets from highly complementary tomographic techniques addresses the fundamental aim of MSR analytical strategies: to maximize data output from highly limited MSR sample quantities.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"13 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025EA004536","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148615375","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}

{"title":"Distributed Acoustic Sensing (DAS) Waveforms: Effects of Source Signature, Geometry, and Attenuation","authors":"Oumeng Zhang,&nbsp;Douglas R. Schmitt","doi":"10.1029/2025EA004948","DOIUrl":"https://doi.org/10.1029/2025EA004948","url":null,"abstract":"<p>Distributed acoustic sensing (DAS) records strain integrated over a finite gauge length depending on incidence angle, frequency, material velocities, fiber curvature, and gauge length. The DAS responses to a monofrequency plane wave of these are well understood. However, neither the full response of a DAS waveform to a source signature pulse over a band of frequencies nor this signature's evolution over the length of a single DAS channel due to attenuation have been examined. We use analytic expressions and numerical simulations to quantify how realistic source wavelets and in gauge attenuation reshape DAS strain/strain rate, including broadening, lobe splitting, and in some cases near, vanishing of the recorded signal. Full elastic wavefield modeling shows that fiber curvature and non-planar wavefronts can further shift apparent transit times relative to co-located point sensors. We illustrate these effects with a field example in which 1 m spaced downhole geophones are used to reconstruct a simultaneously acquired DAS record. The results delineate when DAS behaves like a scaled geophone and when it does not, and they motivate forward modeling for studies that demand high fidelity in timing and spectral content. A series of analytic and numerical tools are provided to assist with such evaluations.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"13 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025EA004948","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148467489","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}