Preprints
Filtering by Subject: Physical Sciences and Mathematics
Acceleration and Spatial Reorganization of Bank Erosion under Prolonged Sediment Starvation: Multi-decadal Evidence from the Vam Nao Channel
Published: 2026-04-28
Subjects: Physical Sciences and Mathematics
The reduction in sediment supply in major deltas worldwide is altering the morphological dynamics of river delta systems. However, the way in which this process leads to the spatial reorganization of erosion has not yet been fully quantified. This study analyzes shoreline variations in the Vam Nao channel, Mekong Delta, over the period 1988–2025 in order to clarify the morphological changes of [...]
Large climate model ensembles reveal underdispersion in seasonal Atlantic tropical cyclone counts
Published: 2026-04-28
Subjects: Atmospheric Sciences, Physical Sciences and Mathematics
Seasonal Atlantic tropical cyclone (TC) counts are commonly modeled as a conditional Poisson process, implying that the distribution of possible seasonal outcomes—the range of TC counts that could plausibly occur in a given year—exhibits equidispersion for a given climate state, with its variance equal to its mean. This assumption underlies many statistical frameworks used for seasonal TC [...]
Soil Remineralization in Agroecological Systems: A Critical Review
Published: 2026-04-28
Subjects: Agriculture, Earth Sciences, Environmental Sciences, Life Sciences, Physical Sciences and Mathematics
Soil degradation threatens global food security, human nutrition, biodiversity, water resources, and climate stability by depleting soil organic matter, exhausting nutrient reserves, and disrupting carbon and nitrogen cycles. Conventional input‑intensive agriculture has delivered yield gains but has also contributed to widespread micronutrient deficiencies, nutrient loading of waterways, soil [...]
Assessment of riverbed evolution in the Vam Nao River under the influence of sand mining using a numerical model
Published: 2026-04-28
Subjects: Physical Sciences and Mathematics
Riverbed sand mining is a major anthropogenic driver of sediment imbalance and riverbank erosion in the Mekong Delta. This study investigates its morphological impacts using the hydrodynamic–morphological model HYDIST, coupled with a sand mining source function (Ssm), to directly simulate unsustainable sand mining. The model is applied to the Vam Nao River, a confluence connecting the Tien and [...]
Efficient Full-Waveform Inversion via QR-Based Data Selection
Published: 2026-04-28
Subjects: Earth Sciences, Physical Sciences and Mathematics
Full-waveform inversion (FWI) is computationally intensive due to the large number of data points, forward simulations, and model parameters. However, realistic acquisition geometries often produce highly redundant linearized systems. In this work, we reformulate post-acquisition data selection as a matrix row-subset selection problem acting directly on the Jacobian of the linearized inverse [...]
Understanding fiber-optic sensitivity to a wavefield: A framework to separate site amplification from orientation effects
Published: 2026-04-27
Subjects: Earth Sciences, Physical Sciences and Mathematics
When analyzing signals from Distributed Acoustic Sensing (DAS), the recorded amplitude across the array can be difficult to interpret, as it is influenced by many parameters. In this work, we explore the theoretical foundations of fiber sensing amplitude transfer functions. We begin with linear fiber segments and progressively extend to more complex geometries to create polarization [...]
A Report on Assumptions and Uncertainties in Modeling Nuclear Winter
Published: 2026-04-26
Subjects: Physical Sciences and Mathematics
Nuclear winter is arguably the biggest consequence of a nuclear war that the field seeks to prevent; experts study nuclear winter to prevent civilizational collapse and widespread catastrophe. A nuclear winter would be, for lack of better words, really bad. As long as the risk of nuclear war exists, so too will the catastrophic risk of a nuclear winter. Much of the modeling and research that [...]
Overshoot pathways of 1.5°C: reversible biophysical change, irreversible socioeconomic impacts
Published: 2026-04-25
Subjects: Physical Sciences and Mathematics, Social and Behavioral Sciences
Exceedance of 1.5°C in the near term is now unavoidable. Among pathways consistent with the remaining carbon budget, an overshoot pathway, in which exceedance is followed by decline to or below 1.5°C through net-negative emissions, is the best case of what remains achievable. Permanent exceedance produces strictly worse outcomes, yet even an overshoot pathway leaves lasting legacies. We propose a [...]
Spatial Assessment of Soil Erosion Risk Using RUSLE and GIS in Upland Agricultural Barangays of Candelaria, Quezon, Philippines
Published: 2026-04-25
Subjects: Physical Sciences and Mathematics
This study integrated Geographic Information System (GIS) and the Revised Universal Soil Loss Equation (RUSLE) model, A= R • K • LS • C • P, to assess soil loss and propose soil conservation strategies in Candelaria, Quezon, Philippines, addressing increasing erosion evidenced by collapsing hillsides, sedimentation, and soil displacement from construction. The RUSLE model, with adjustments in the [...]
Evaluation of H2O-CO2 solubility models in silicate melts: Precision and accuracy of vapor saturation pressure and composition
Published: 2026-04-25
Subjects: Physical Sciences and Mathematics
Solubility models for H2O and CO2 in silicate melt are crucial in igneous petrology and volcanology, in particular for calculating the pressure of vapor saturation of melts from their dissolved volatile content as a barometer, as well as melt and vapor compositions and proportions during degassing. We assessed the accuracy and precision of the calculated pressure of vapor saturation and [...]
Microphysical Evolution of Precipitation During Convective Storm Life-Cycles and Implications for Radar QPE: Combined Radar–Disdrometer Observations from Kolkata, Eastern India
Published: 2026-04-25
Subjects: Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Through dedicated observations with a Joss–Waldvogel disdrometer at Dumdum (22.65°N, 88.43°E) and the S-band Doppler Weather Radar (DWR) (22.57°N, 88.35°E) over Kolkata, this study provides in-depth analysis of drop size distribution (DSD) evolution over each stage from initiation to decay of contrasting convective storms over Kolkata, eastern India due to its complicated terrain in monsoon [...]
Statistics of curvature in the submesoscale surface ocean
Published: 2026-04-24
Subjects: Physical Sciences and Mathematics
Ocean submesoscale (1--10\,km) variability is hypothesised to contribute substantially to upper-ocean vertical exchange and heat fluxes, but the three-dimensional turbulent nature of the variability makes it difficult to interpret submesoscale variability dynamically. Statistics of velocity gradients are often analyzed to characterize the nature of submesoscale dynamics. Previous analyses show [...]
Continuous Water Surface Elevation Estimates Using Deep Learning with Legacy Altimetry and Surface Water and Ocean Topography Data
Published: 2026-04-24
Subjects: Earth Sciences, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Water Resource Management
We present the development of a high-temporal-resolution global dataset of daily river water surface elevation (WSE), spanning January 2008 through May 2025. By utilizing a deep learning framework to integrate legacy satellite altimetry and the Surface Water and Ocean Topography (SWOT) mission data, we produced a continuous record covering 9,184 river reaches, 5,926 rivers, and 1,342 basins. The [...]
Airborne imaging spectrometer measurements of methane releases under turbulent conditions
Published: 2026-04-24
Subjects: Earth Sciences, Environmental Sciences, Other Earth Sciences, Physical Sciences and Mathematics, Physics
Methane plume detection and quantification from airborne and spaceborne platforms offers a promising approach for monitoring localized greenhouse gas emissions. Its performance must be demonstrated under realistic but controlled conditions. An airborne demonstrator of a compact shortwave infrared imaging spectrometer developed for the AIRMO Earth observation mission was therefore evaluated during [...]
The biodiversity paradox: declining conservation discourse amid ecological crisis in global urban policies
Published: 2026-04-24
Subjects: Life Sciences, Physical Sciences and Mathematics
Despite escalating biodiversity crises, conservation discourse in urban environmental policies has declined, revealing a governance paradox in which ecological urgency is inversely correlated with policy representation. We analyzed 202 urban environmental policies from 85 countries spanning 1984-2025 using computational text analysis (LDA, NMF, hierarchical clustering). The results reveal an [...]