Preprints
There are 7721 Preprints listed.
The four-vector potential of equatorial shallow water waves from Hamilton’s principle
Published: 2026-08-31
Subjects: Physical Sciences and Mathematics
Linear shallow water waves on an equatorial β-plane can be represented as the states of a charged particle minimally coupled to a four-vector potential whose analogue magnetic field is uniform and proportional to β/c_g. There the potential is written down and verified rather than derived. We show that it need not be assumed. In the Eulerian variational principle for rotating flow the Coriolis [...]
A particle representation of tropical shallow water waves
Published: 2026-08-31
Subjects: Physical Sciences and Mathematics
The linearized shallow water equations on a general β-plane reduce to a single meridional structure equation for the meridional velocity. We show that this equation is exactly the Schrödinger equation for a “charged” particle minimally coupled to a four-vector potential whose analogue magnetic field, B_W=-(β/c_g ) x ̂, is uniform and westward. No ad hoc term is required: every term is generated [...]
The Current State of Research on Deformation, Strain, and Velocity across the Alpine-Himalayan Belt Using Transcontinental Sentinel-1 InSAR and GNSS
Published: 2026-08-31
Subjects: Geophysics and Seismology, Tectonics and Structure
Research on present-day deformation across the Alpine-Himalayan belt has crossed a methodological threshold. Regional Sentinel-1 studies in Anatolia, Iran, and Tibet have now been joined by the first transcontinental three-dimensional velocity and horizontal strain-rate field, derived from more than 222,000 radar images acquired during 2016-2024 and a belt-wide GNSS compilation. The result [...]
Deep-learning-based denoising and interpolation of small displacements caused by fault slip using InSAR and GNSS data: Application to the 2019 Mw 6.2 Hyuga-nada earthquake
Published: 2026-08-31
Subjects: Applied Statistics, Earth Sciences
In recent years, deep learning techniques have become important tools in Solid Earth science, including geodesy. Previous studies have applied deep learning techniques to synthetic aperture radar interferometry (InSAR) or Global Navigation Satellite System (GNSS) data, which are two major observation techniques of satellite geodesy, to mitigate noise or detect small signals. Because InSAR and [...]
Exploring the Signal Content of Continuous Seismic Recordings at Station NKC (West-Bohemia/Vogtland) With a Self-Supervised Vision Transformer
Published: 2026-08-30
Subjects: Physical Sciences and Mathematics
Continuous seismic recordings contain a wide variety of signal types (earthquakes, quarry blasts, induced events, and diverse background and anthropogenic noise) but sorting them into meaningful categories usually relies on manual inspection. Here we take an exploratory approach and ask a deliberately simple question: what kinds of signals are actually present in the continuous record of station [...]
Super El Niño Winters and the Arctic Polar Vortex: Response Heterogeneity, QBO Modulation, and a Prospectively Defined Test for Winter 2026/27
Published: 2026-08-30
Subjects: Atmospheric Sciences, Climate, Earth Sciences, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Other Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
In the three strongest El Niño winters of the instrumental record (1982/83, 1997/98, 2015/16) the Arctic polar vortex did not collapse in a major midwinter sudden stratospheric warming (SSW). This study starts from the premise that the observation is not a paradox: 58% of El Niño winters contain at least one major SSW, so the chance probability of three consecutive SSW-free winters is 0.42³≈0.07, [...]
Material demand and supply-chain assessment of U.S. electricity system transitions
Published: 2026-08-30
Subjects: Engineering
Decarbonizing the U.S. electricity sector will require rapid deployment of generation, storage, and transmission infrastructure, increasing demand for materials. We develop an integrated framework that quantifies annual and cumulative material demand from 2027 to 2050 across an ensemble of U.S. electricity futures spanning alternative policy, technology, and economic assumptions. Across the [...]
Upper-Scale Structural Evaluation of the Forearc Weak Suture Zone and the Pacific Plate Interface — An Analysis Based on Precursor Data (No.1778) —
Published: 2026-08-30
Subjects: Physical Sciences and Mathematics
This study reinterprets precursor data (No.1778) published by the Yatsugatake South Base Observatory using the framework of seismology and tectonics, in order to evaluate the upper-scale structural potential of the forearc weak suture zone and the Pacific Plate interface beneath the Kanto Basin. The precursor data are not used for earthquake prediction; instead, they are treated as aggregate [...]
Deep Learning-Based Meteorological Data Downscaling: A Comparative Study with Physics Informed CNN and a Component-Level Ablation Analysis
Published: 2026-08-29
Subjects: Computer Engineering, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Meteorological statistical downscaling is a critical technique for deriving high-resolution climate information from coarse global reanalysis products. This experiment investigates the application of five representative deep learning architectures for downscaling ERA5 reanalysis 2m temperature fields from 1° to 0.25° spatial resolution (4x upscaling factor) over the China region, spanning the [...]
Climate change has intensified exceptional El Niño events like the 2026/27 forecast
Published: 2026-08-29
Subjects: Applied Statistics, Climate, Physical Sciences and Mathematics, Statistics and Probability
Extreme El Niño events disrupt weather across much of the globe, with adverse effects on agriculture, fisheries and economic output that persist for several years. Event attribution routinely quantifies the human influence on individual heatwaves, droughts and floods, but its application to the El Niño events that drive many of them has been much more limited. Here we investigate the 2026/27 El [...]
Manufactured vulnerability in the Ganges–Brahmaputra–Meghna delta: engineered drivers and coastal displacement in south-west Bangladesh
Published: 2026-08-29
Subjects: Life Sciences, Marine Biology, Risk Analysis, Social and Behavioral Sciences
Displacement from the Ganges–Brahmaputra–Meghna delta in south-west Bangladesh is usually attributed to sea-level rise, cyclones and salinity. The evidence assembled here points to a jointly produced process, in which hazards act together with engineered landscape change, governance arrangements and the interval households spend unable to return. Peer-reviewed and grey literature for Khulna, [...]
Limited sensitivity of published InSight RISE rotation products to the seismically proposed Martian inner-core family: a prospectively specified reanalysis
Published: 2026-08-29
Subjects: Geophysics and Seismology, Planetary Geophysics and Seismology
The InSight Rotation and Interior Structure Experiment (RISE) measured the rotation of Mars by radio tracking; Le Maistre et al. (2023) report the detection of the Free Core Nutation (FCN, period −243 ± 3.3 d) and no detection of the Free Inner Core Nutation (FICN) that a solid inner core would add. Bi et al. (2025) subsequently reported a 613 ± 67 km solid inner core from seismology, without [...]
The Bhote Koshi–Trishuli flash flood of 26 August 2026, Rasuwa, Nepal: warning latency exceeded flood travel time
Published: 2026-08-29
Subjects: Earth Sciences, Environmental Monitoring, Hydrology
An ice-rock mass detached from the northern flank of the Langtang massif, Nepal, at 08:37:10 Nepal Time on 26 August 2026. It blocked the Lhende Khola and released a cascade that killed more than 500 people along the Bhote Koshi-Trishuli-Narayani corridor. This study measures the warning chain end to end, timing the front at six stations from ten-minute stage series recovered from the river-watch [...]
A qualitative content analysis of wildfire smoke preparedness and response plans in the United States and Canada
Published: 2026-08-29
Subjects: Public Health
Wildfires in North America have become more frequent and intense in recent years. This increase can be attributed to climate change, which has led to higher temperatures and altered precipitation patterns, creating conditions that favor wildfires. In addition, human activities, such as land development, forest management practices, and the ignition of fires, further contribute to the rising [...]
Space-based InSAR with sub-daily temporal baselines
Published: 2026-08-28
Subjects: Aerospace Engineering, Earth Sciences, Engineering, Physical Sciences and Mathematics
Interferometric synthetic aperture radar (InSAR) underpins the Surface Deformation and Change observable prioritized by the 2018 decadal survey, yet the temporal sampling of current assets aliases many transient geophysical processes. For single-satellite repeat-pass InSAR, satellite orbits accommodate temporal baselines at integer nodal day intervals down to a single nodal day. Processes that [...]