Preprints
Filtering by Subject: Physical Sciences and Mathematics
Seeing Cities in Depth: Subsurface Urban Expansion and the Case for Volumetric Monitoring and Accountability
Published: 2026-06-10
Subjects: Physical Sciences and Mathematics, Social and Behavioral Sciences
Urban science can measure surface and aboveground change with increasing precision. Satellites, building-footprint datasets, and emerging three-dimensional products now track urban land, building height, and built volume. Yet these tools still struggle to capture urbanization below ground. This Perspective defines subsurface urban expansion as the extension of urbanization below the local ground [...]
A Rotating Air-Ring Model for Atmospheric Vortices and a Peripheral Drag Concept for Tornado Mitigation
Published: 2026-06-10
Subjects: Education, Engineering, Physical Sciences and Mathematics
This study introduces Latent Angular Momentum (LAM) as a heuristic parameter for understanding the intensification of rotating atmospheric vortices. Using a simplified air-ring model based on the conservation of angular momentum, we derive an analytical expression for tangential wind speed as a function of radial contraction and latitude. Model predictions yield physically plausible initial radii [...]
A Unified Treatment of SKS Splitting and Surface-Wave Anisotropy for Media with Arbitrary Elastic Symmetry
Published: 2026-06-09
Subjects: Physical Sciences and Mathematics
Observations of SKS splitting and surface-wave azimuthal anisotropy are two of the primary geophysical constraints on crust and upper-mantle anisotropy, yet the two methods often yield apparently inconsistent inferences about the strength and vertical extent of anisotropy. Here we show that neglecting anisotropy parameters associated with Rayleigh-Love coupling is an important and largely [...]
High-resolution pavement material data can improve estimates of water supply from precipitation to street trees
Published: 2026-06-09
Subjects: Physical Sciences and Mathematics
Impervious surfaces in urban landscapes strongly influence how precipitation supplies water to trees. Most data on imperviousness are satellite derived restricting our ability to analyze impacts of imperviousness at the scale of single tree catchments: the area covering tree roots. To address this challenge, we compiled a high-resolution dataset for Berlin, Germany, that specifies pavement [...]
Floods as a window of opportunity: When and why extreme events trigger adaptation
Published: 2026-06-08
Subjects: Physical Sciences and Mathematics, Social and Behavioral Sciences
Disasters can open windows of opportunity for climate adaptation—moments when heightened public attention makes it possible to advance policies and measures that would otherwise struggle to gain traction. Yet whether and how floods shape public adaptation discourse remains unclear. Here, we quantify how flood severity influences media coverage on 12 adaptation measures across 274 German districts [...]
Impacts of Potential Solar Radiation Modification: Systematic Review Reveals Challenges and Opportunities
Published: 2026-06-06
Subjects: Agriculture, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Life Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Planetary Sciences, Plant Sciences
Solar radiation modification (SRM) is a proposed temporary intervention to limit global warming while mitigation efforts continue. Understanding its potential consequences for human and natural systems is essential for informed deliberations. We conducted a systematic review of the peer-reviewed literature on SRM impacts published through May 2024, identifying 289 studies, including 261 primary [...]
ADMM-Guided Physics-Informed Deep Learning for Two-Dimensional Acoustic Impedance Inversion with Reweighted ℓ1 Sparse Regularization
Published: 2026-06-06
Subjects: Physical Sciences and Mathematics
Acoustic impedance inversion is ill-posed because post-stack seismic data are band-limited and noisy. Reweighted ℓ1 sparse inversion sharpens impedance boundaries but, applied trace by trace, ignores lateral geological continuity. We present a two-dimensional ADMM-guided physics-informed neural framework in which a reweighted ℓ1 ADMM estimate (after He et al., 2022) serves as a physics prior for [...]
Exact solutions for ice flow across the no-slip to free-slip transition
Published: 2026-06-05
Subjects: Physical Sciences and Mathematics
The downhill flow of a viscous ice stream across a no-slip to free-slip transition remains elusive to exact solutions due to the existence of singularities. Here we replace the point-wise sharp transition by a functional dependency of parametrised horizontal length. Analytical solutions are found for the steady Navier-Stokes flow with Newtonian properties. Our solution remains smooth and [...]
Empirical Relationships Between Ground Motion Intensities and JMA Seismic Intensity Scale
Published: 2026-06-05
Subjects: Physical Sciences and Mathematics
There is a growing appetite for parametric Japanese earthquake insurance products that use Japanese Meteorological Agency seismic intensity, IJMA, triggers. However, most earthquake risk models used to price these contracts do not compute IJMA directly, instead relying on conversions that introduce additional basis risk. Here, we present empirical parameterisations of IJMA as a function of all [...]
Satellite Embedding: A Review
Published: 2026-06-04
Subjects: Earth Sciences, Physical Sciences and Mathematics
Satellite embeddings have become a practical interface between large-scale Earth observation data and downstream geospatial analysis, yet the liter ature is still organized mainly around foundation models rather than the embeddings they produce. This review reframes the area from an embedding centered perspective. We first define satellite embeddings as reusable latent representations derived [...]
Constraints on magma source conditions from hydraulic fracture models and seismic observations of dyke tip deceleration
Published: 2026-06-04
Subjects: Physical Sciences and Mathematics
Seismicity shows that magmatic dykes decelerate as they propagate laterally. Hydraulic fracture theory shows this deceleration relates to the coupling between the source and the dyke. Here, we use hydraulic fracture models to derive scaling laws for the length, width, and shape of dykes driven by three source boundary conditions: constant flux, constant pressure, and a finite volume release. [...]
Late Cretaceous channel flow in Western Arizona: Implications for the ancestral origin of metamorphic core complexes
Published: 2026-06-04
Subjects: Physical Sciences and Mathematics
The origin of ancestral ’extensional’ shear fabrics in metamorphic core complexes (MCCs) in the Colorado River Extensional Corridor remains a tectonic mystery. Here we show that Late-Cretaceous metamorphic rocks and migmatites in the Harcuvar-Harquahala and Granite Wash Mountains MCCs reached peak metamorphic conditions of ca. 0.75 GPa and 780°C and were extruded towards the SW onto lower grade [...]
Time domain full waveform inversion with decomposed Gauss-Newton Hessian
Published: 2026-06-03
Subjects: Physical Sciences and Mathematics
Full waveform inversion (FWI), a nonlinear data fitting approach for parameter estimation, is generally implemented with local optimization methods. The convergence of the iterations can be slow when the steepest descent direction provided by the negative gradient of the data misfit function is not preconditioned by the inverse full Newton Hessian or its linear approximation, namely the [...]
Comparing Process-Based and Machine Learning Models for Streamflow Prediction in the Kaligandaki River Basin, Nepal
Published: 2026-06-03
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Water Resource Management
Reliable daily streamflow prediction is critical for hydropower operations, flood risk management, and irrigation planning in monsoon-dominated Himalayan river basins. While both process-based and machine learning (ML) approaches have been used for such tasks, systematic comparisons that decompose the sources of performance differences remain scarce. This study evaluates seven configurations: a [...]
Harmonized global to regional gridded methane inventories in a discrete global grid framework
Published: 2026-06-03
Subjects: Engineering, Physical Sciences and Mathematics
Existing gridded methane emission inventories vary widely in resolution, sector schemes, formats, and units, hindering cross-comparison, integration with measurements, and use in emerging analytical frameworks, particularly because latitude-longitude grids have non-uniform cell areas that bias comparison and aggregation. Here, we present a harmonized methane emissions dataset that standardizes 13 [...]