Preprints
There are 7999 Preprints listed.
Acceleration and Spatial Reorganization of Bank Erosion under Prolonged Sediment Starvation: Multi-decadal Evidence from the Vam Nao Channel
Published: 2026-04-29
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 [...]
Spaceborne imaging spectrometry of methane plumes: Quantifying the benefit of aerosol lidar
Published: 2026-04-22
Subjects: Earth Sciences, Environmental Sciences, Physics
Column averaged mixing ratios of trace gases, such as methane (XCH4), from spaceborne pushbroom spectrometers can be used to detect corresponding plumes and retrieve enhancements (ΔXCH4), i.e., the difference between plume and background XCH4. Over the global dust belt, however, significant scattering by dust aerosols may cause biased XCH4 that may propagate into biased ΔXCH4. To correct this, a [...]
Models of Thermosyphon Performance, Design, and Influence on Glacier Flow
Published: 2026-08-03
Subjects: Glaciology
Sea-level rise threatens coastal communities worldwide, and the acceleration of West Antarctic glaciers is the largest source of uncertainty in sea-level projections. The melt rate at the ice-bed interface is a primary control on the flow speed of fast-moving Antarctic glaciers and ice streams, whose beds are lubricated by meltwater and governed by thermodynamic feedback. Thermosyphons are [...]
Accretionary Pedogenesis and Holocene Climate Evolution in Black Soil Region of Northeast China: Evidence from a Sedimentary Profile
Published: 2026-04-15
Subjects: Environmental Sciences
The black soil region of the Songnen Plain, one of the world's three major black soil belts, is critical for China's grain security, yet the formation mechanism of its thick, organic-rich soils remains insufficiently quantified. In this study, we investigate the ZYHPM01 profile in the eastern Songnen Plain using grain-size end-member analysis (EMA), multi-proxy geochemical tracers, and [...]
HPHT Micro-to-Nano Seismic Comparison of GEIOS Nitrogen Hybrid Gas Nanofoam vs. Water-Proppant EGS
Published: 2026-06-18
Subjects: Geophysics and Seismology
Statement of peer-review status: This is a non-peer-reviewed preprint. The work derives from internal laboratory testing at Nanogeios Laboratory and has not been submitted to a peer-reviewed journal. For patent and intellectual-property security, certain sources and proprietary technical details (e.g., exact nanoparticle composition and surfactant/stabiliser chemistry) are intentionally not [...]
Terrestrial formation of calcium sulfate and carbonate assemblages in Atacama CO chondrites: Implications for Martian evaporitic environments
Published: 2026-04-15
Subjects: Cosmochemistry, Earth Sciences, Geochemistry, Planetary Geochemistry, Planetary Geology, Planetary Mineral Physics, Planetary Sciences
Evaporites are frequently reported in carbonaceous chondrites from hot and cold deserts, yet their origin remains debated between formation on the parent body or by post-fall terrestrial alteration. Here, we present a systematic characterization of Ca sulfate and Ca carbonate assemblages in four CO carbonaceous chondrites from different dense collection areas of the Atacama Desert (Los Vientos [...]
Simulation of Groundwater Flow To Evaluate Hydrogeologic Controls on a PFAS Plume, Coakley Landfill Superfund Site, Rockingham County, New Hampshire
Published: 2026-04-09
Subjects: Earth Sciences, Environmental Health and Protection, Environmental Sciences, Geology, Hydrology, Physical Sciences and Mathematics, Water Resource Management
Per- and polyfluoroalkyl substances (PFAS), including perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), have been detected at combined concentrations above 2,000 nanograms per liter (ng/L) at groundwater seep locations near the Coakley Landfill Superfund site, in North Hampton, New Hampshire. The landfill was active from 1972 to 1985. An impermeable cap was placed on the [...]
‘Egg that tastes like egg’: An ethnographic and economic inquiry into the assets and challenges of the organic farming market in the Canary Islands
Published: 2026-04-23
Subjects: Environmental Studies
The development of self-sufficient organic food systems has become an important focus in the Canary Islands, where reliance on imported foods and conventional agriculture are predominant. This study examines the main challenges and opportunities in the market through eleven on-site, semi-structured interviews combined with participant observation. Thematic analysis was conducted and findings were [...]
Estimating Ice Shelf Thickness in Grounding Zones of the Filchner-Ronne Ice Shelf with Tidal Flexure from ICESat-2
Published: 2026-04-29
Subjects: Glaciology
In the grounding zones of Antarctic ice sheets, grounded ice sheets become floating ice shelves at the triple junction of the ice, ocean, and bedrock. Ice downstream of the grounding line rises and falls with ocean tides while ice upstream of it does not, creating kilometers wide flexure zones. Ice thickness in the flexure zone cannot be well estimated by assuming it is in hydrostatic [...]
Quantifying 3D Modeling Errors in Time-Domain Electromagnetics: Implications for Deterministic and Probabilistic Inversions
Published: 2026-04-28
Subjects: Geophysics and Seismology
Subsurface resistivity in geophysics is commonly estimated indirectly from dependent measurements. This relationship can be approximated in a forward operator using physical models, such as Maxwell’s equations for time-domain electromagnetics (TDEM), where measured voltages in receiver coils arise from decaying magnetic fields. In TDEM, the inverse operator usually does not exist, so inversion [...]
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
Cities are increasingly measured through surface land cover and aboveground form, even as urban activity expands below ground. This Perspective develops an integrated approach for making that expansion visible and governable. First, it defines subsurface urban expansion as durable growth or intensification of urban activity below the local ground surface through new or expanded occupation, use, [...]
A Global Dataset of Alpine Treeline Elevational Transects
Published: 2025-10-23
Subjects: Earth Sciences, Environmental Monitoring, Forest Sciences, Terrestrial and Aquatic Ecology
The Alpine Treeline Ecotone (ATE) is an important ecological transition zone at the juncture of montane forests and alpine vegetation. It serves as a crucial habitat for diverse species and a sensitive indicator of climate change. Consistent characterization of the elevational gradients of ATE is challenging due to complex topography and data limitations. This study introduces a comprehensive [...]
Association Between Coastal Water Exposure and Urinary Tract Infection in Adult Females
Published: 2026-04-15
Subjects: Public Health
Gastrointestinal illness is a known risk of swimming in coastal waters which are contaminated by sewer overflows, septic tanks, domestic pets, or wildlife. Limited research has assessed the risk of urinary tract infections (UTIs) from recreating in coastal waters, even though they are an established reservoir of UTI pathogens. We performed a prospective study of beachgoers in Santa Cruz, [...]
DCENT-I: A Globally Infilled Extension of the Dynamically Consistent ENsemble of Temperature Dataset
Published: 2025-08-31
Subjects: Atmospheric Sciences, Climate, Oceanography
A spatially infilled Dynamically Consistent Ensemble of surface Temperature (DCENT-I) has been created by infilling land-air and sea-surface temperatures from DCENT using ordinary kriging with anisotropic and heterogeneous kernels. By incorporating air-temperature anomalies over sea-ice areas, DCENT-I provides spatially complete monthly temperature fields at 5° resolution from 1850 to the present [...]
Nitrogen Mineralization of Cover Crop Residue Depends on Carbon to Nitrogen Ratio and Soil Temperature
Published: 2025-05-06
Subjects: Agriculture
Groundwater nitrate contamination is largely attributed to fertilizer and intensive livestock manure inputs in agricultural systems. California’s Salinas Valley is an area where state policy is aiming to reduce nitrate leaching. Non-legume winter cover crops can help decrease nitrate leaching by scavenging residual soil nitrogen (N) during winter fallow periods following the cropping season. [...]