Preprints
Filtering by Subject: Physical Sciences and Mathematics
Large-Scale Mapping and Graph-Theoretic Characterization of Arctic Tundra Capillary Networks From Submeter Satellite Imagery
Published: 2026-06-24
Subjects: Physical Sciences and Mathematics
Abstract— Tundra capillary networks (TCNs) are visible surface-drainage features associated with ice-wedge polygon terrain that can influence lateral surface-water redistribution across Arctic landscapes. However, TCN systems remain poorly characterized at regional scales because their narrow morphology, variable surface expression, and submeter scale have limited the development of scalable [...]
Where to Watch the Water: Multi-Sensor Network Design Optimization for Inland Flood Detection
Published: 2026-06-24
Subjects: Earth Sciences, Environmental Sciences, Geomorphology, Hydrology, Physical Sciences and Mathematics, Water Resource Management
Inland flood detection is often constrained less by sensor availability than by where sensors are placed along branching river networks, especially in ungauged headwaters where floods often initiate. We present a three-phase, decisionfocused framework for designing basin-by-basin multi-sensor flood detection networks that coordinate water-level, discharge, and camera sensors while explicitly [...]
Earthquakes Source Scaling at Subfault Scales
Published: 2026-06-23
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Establishing scaling laws for large earthquakes remains challenging due to the heterogeneity of methodologies and datasets used to produce finite-fault models. In this study, we analyze source properties for 264 earthquakes using the NEIC finite-fault database, expanding previous efforts by examining rupture behavior over a broader magnitude range and capturing both established scaling trends and [...]
Creating story lines on floods: relating climate-change uplift to (extreme) experienced and future flooding events
Published: 2026-06-23
Subjects: Engineering, Physical Sciences and Mathematics
Fluvial flooding remains one of the most significant climate-related hazards worldwide, with its impacts intensified by increasing urbanisation, land-use change, and climate change. We apply the flood-excess volume (FEV) methodology to analyse major recent flood events on the River Aire in Leeds, UK, and specifically to the 2015 Boxing Day and February 2020 floods, as a basis for evaluating the [...]
Detecting Harmful Algal Blooms in the Gulf of Maine using a Hybrid Model
Published: 2026-06-22
Subjects: Engineering, Physical Sciences and Mathematics
Harmful algal blooms are a growing threat to marine ecosystems, aquaculture, public health and tourism industries. This study quantifies the value of augmenting simulated outputs of a regional hydrodynamic model with satellite data input to detect harmful algal blooms using machine learning model in Gulf of Maine. And evaluates performance using in-situ Imaging FlowCytobot observations spanning [...]
Stress triggering in a rain-induced earthquake swarm in the Palghar region, western India
Published: 2026-06-20
Subjects: Earth Sciences, Physical Sciences and Mathematics
Rain-triggered seismicity has been reported only in a few regions globally and is typically short-lived. However, an earthquake swarm, inferred to be rain-induced in previous studies, persisted with intense activity for over two years in Palghar, western India. Between January 2019 and November 2020, ~8,300 well-located earthquakes with horizontal and depth uncertainties ≤ 1.5 km were recorded at [...]
Underestanding Tipping Points Caused by Climate Change in Iran: A review
Published: 2026-06-19
Subjects: Physical and Environmental Geography, Physical Sciences and Mathematics
Climate tipping points are caused by global warming and refer to critical thresholds in the climate system, crossing which leads to irreversible changes in climate conditions, ecosystems, and even socio-economic structures. These changes may occur over long time scales, ranging from several decades to hundreds of years, and their effects are often negative and threatening, although some positive [...]
Regional anthropogenic aerosol reductions amplify probability of record-breaking heat extremes
Published: 2026-06-18
Subjects: Physical Sciences and Mathematics
Record-breaking heat extremes are becoming more likely due to anthropogenic climate change, with their probability depending on the regional warming rate. Anthropogenic aerosol forcing modulates these warming rates, and aerosols are declining globally. However, the influence of aerosols on the probability of record-breaking heat extremes remains unclear. Here, we assess how aerosol trends alter [...]
Linking double seismic zones to oceanic lithosphere rheological layering: the role of mid-lithospheric discontinuities
Published: 2026-06-18
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics
The origin of the ubiquitous lower seismic layer (LSL) in double seismic zones (DSZs) within subducting oceanic lithosphere remains one of the most persistent unresolved problems in subduction-zone seismicity. Analysis of recent geophysical observations reveals a close spatial association between the LSL and the oceanic mid-lithospheric discontinuity (MLD), a feature attributed to the [...]
Seismic Evidence for an Ultralow Velocity Zone Beneath the Cape Verde Hotspot
Published: 2026-06-17
Subjects: Physical Sciences and Mathematics
Mega ultralow velocity zones (mega-ULVZs), thin patches of strongly reduced seismic velocity with large horizontal extent just above the core-mantle boundary (CMB), are increasingly found beneath deep mantle plumes, suggesting a link to hotspot volcanism. The Cape Verde hotspot is thought to overlie a deep plume, but whether a ULVZ exists at its base has remained unknown. We present [...]
Tropical cyclones intensify mesoscale eddy variability and accelerate Western Boundary Current instability
Published: 2026-06-17
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Tropical cyclones strongly disrupt the upper ocean, yet their influence on mesoscale variability in western boundary current systems remains poorly quantified. The Gulf of Mexico, where the Loop Current regularly sheds large warm-core eddies, offers an ideal setting to examine how hurricanes reshape mesoscale dynamics. Using a high-resolution ocean model and hurricane-denial experiments, we [...]
ENSO-Driven Modulation of the Caribbean Subsurface Salinity Maximum
Published: 2026-06-16
Subjects: Climate, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
This study identifies El Niño–Southern Oscillation (ENSO) as the primary driver of interannual subsurface salinity variability in the Caribbean Sea. Using 30 years of high-resolution, data-assimilative ocean reanalysis (1993–2022), we show that the Subsurface Salinity Maximum (SSM) closely tracks ENSO cycles: El Niño events correspond to a saltier and deeper SSM, while La Niña drives a fresher [...]
Internal Processes Driving the Slow-to-Fast Transition of a Rockslide
Published: 2026-06-16
Subjects: Physical Sciences and Mathematics
Landslides may creep slowly for decades to centuries under external influences such as rainfall or seismic shaking. Predicting when and how they transition into catastrophic acceleration remains a major challenge because the internal processes driving failure occur at depth and are often not evident from surface observations alone. Here, we combine local seismic and geodetic measurements to [...]
Why the Earth Exhibits Interhemispheric Albedo Symmetry: Erosion–formation asymmetry of low-cloud responses to circulation reorganization.
Published: 2026-06-16
Subjects: Atmospheric Sciences, Climate, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Earth exhibits a striking near symmetry in interhemispheric mean albedo despite substantial asymmetries in surface properties, aerosols, and geography. Whether this symmetry is coincidental or dynamically constrained remains unresolved. Here we present a minimal theoretical framework showing that a moist atmosphere provides a physically constrained, but bounded, tendency to oppose [...]
Samoa Basin Abyssal Mapping: Box Coring Leg
Published: 2026-06-15
Subjects: Physical Sciences and Mathematics
This cruise report describes work from leg three of the NOAA American Samoa Abyssal Mapping effort, OPR-T900-KR-26. Leg one preceded this effort and collected ship-based acoustic data. Leg two collected autonomous underwater vehicle (AUV) data and began before, continued contemporaneously, and finished subsequently to leg three. The USGS field activity number assigned to this expedition is [...]