Preprints
There are 6627 Preprints listed.
Modelling void fraction distributions in breaking hydraulic jumps
Published: 2026-02-02
Subjects: Engineering
We present two models for predicting void-fraction distributions in hydraulic jumps, addressing the limitations of the conventional two-layer formulation in representing continuous profiles. The first model introduces a two-state convolution to describe the smooth transition between the turbulent shear and roller regions, while the second applies a superposition framework to capture the [...]
Rethinking Vertical Transport of Buoyant Plastics in Open Channels
Published: 2026-02-01
Subjects: Engineering, Physical Sciences and Mathematics
Recent studies have demonstrated that the vertical distribution of positively buoyant plastic particles in turbulent open channel flows can be described by a modified Rouse profile. However, implicit observations in the literature also suggest that floating particles remain confined to the air–water interface due to surface tension forces. To shed more light on this apparent contradiction, we [...]
Ichnoliths as results of authigenesis associated with aquatic animal traces
Published: 2026-02-01
Subjects: Sedimentology
Animal-made bioturbational structures modify physio-chemical conditions and biota on the sediment surface and below. The behavior of the trace makers chiefly causes such changes by sediment irrigation, mucus lining, organic matter storage, microbial gardening etc. Such traces are preferential loci for accumulation of organic material that may foster syn- to post-bioturbational mineral [...]
Coordinated satellite, aircraft, and ground-based observations of a large transient methane release
Published: 2026-02-01
Subjects: Atmospheric Sciences, Environmental Monitoring, Oil, Gas, and Energy
We present results from a Very Large Methane Release (VLMR) experiment evaluating methane retrievals from the Geostationary Operational Environmental Satellites (GOES) Advanced Baseline Imagers (ABIs) and multiple low-Earth-orbit imagers with high point-source detection limits. The experiment coordinated observations of a U.S. gas pipeline blowdown with nine satellites, two aircraft, and a [...]
What Companies Say vs. What Matters: LLM Analysis of Biodiversity Disclosures in Oil and Gas
Published: 2026-01-31
Subjects: Artificial Intelligence and Robotics, Biodiversity, Oil, Gas, and Energy, Sustainability
The power system ecosystem encompasses infrastructure intensive industries such as electric utilities, hydropower operators, oil and gas producers, and mining companies supplying critical minerals. These industries share a common challenge: their physical assets interact extensively with natural ecosystems, creating dependencies and impacts that increasingly draw investor and stakeholder [...]
Chemical Dosage Prediction for Drinking Water Treatment Using Random Forest and Polynomial Regression
Published: 2026-01-31
Subjects: Engineering
Predictive modeling of chemical dosage based on raw water quality can be useful in decision-making in operating a water treatment plant. In this study, two statistical methods, i.e., random forest and polynomial regression, are used for modeling the chemical usages in drinking water treatment based on the measured water quality parameters in source water. The daily chemical dosages and eight [...]
An Accessible NDVI Classification Tool for Urban and Suburban Vegetation Change Analysis
Published: 2026-01-31
Subjects: Geographic Information Sciences, Remote Sensing
This paper presents a web-based research method for studying changes in vegetation in urban and suburban contexts between 2018 and 2024. The system uses the Normalized Difference Vegetation Index (NDVI) to analyze imagery for each time period and classify land surface types. After classification, correlation and regression analysis are applied to explain connections between urbanization and [...]
Magmatic volatile budgets of the 2014 Tavurvur eruption at Rabaul Caldera, Papua New Guinea
Published: 2026-01-30
Subjects: Earth Sciences, Geochemistry, Volcanology
Rabaul is a caldera volcano on New Britain Island, Papua New Guinea, whose active cone Tavurvur ranks seventh globally for long-term SO2 and CO2 emissions. It is unknown why Rabaul is such a strong emitter of volcanic gases. Magma mixing between basaltic and dacitic magmas is envisioned to play a fundamental role in driving eruptions at Rabaul, but the compositions of mafic recharge magmas and [...]
Analyzing volcanic-like earthquakes with distributed acoustic sensing using a short segment of the Tongan seafloor telecommunications cable
Published: 2026-01-30
Subjects: Volcanology
The 2022 Hunga Tonga-Hunga Haʻapai (HTHH) eruption highlighted the need for monitoring submarine volcanoes. Distributed Acoustic Sensing (DAS), utilizing existing seafloor cables offers a promising solution. We analyze a one-week DAS dataset recorded in February 2023, one year after the eruption, using a 30-km segment of the domestic telecommunication cable in Tonga. The previous study (Nakano et [...]
Mathematical modeling of dialectical emergent hybrid regimes in ecosystems
Published: 2026-01-30
Subjects: Life Sciences
Traditional resilience theory often models complex systems as toggling between discrete alternative regimes, such as clear-water and turbid states in shallow lakes, each stabilized by internal feedback. While analytically powerful, this binary paradigm overlooks more nuanced dynamics observed in many real-world systems: the emergence of hybrid regimes that blend structural and functional elements [...]
Who holds Brazil’s biodiversity? The pivotal role of private landholders
Published: 2026-01-29
Subjects: Social and Behavioral Sciences
The urgency of tackling the biodiversity crisis across the tropics is clear, yet governance structures such as land tenure can act as barriers or enablers for conservation. Here, we focus on Brazil, a megadiverse country that has made major efforts to link deforestation to individual properties through self-reported environmental registries. Yet, how these efforts support biodiversity explicitly, [...]
Applicability of machine learning-based downscaling method to climate change prediction
Published: 2026-01-29
Subjects: Oceanography and Atmospheric Sciences and Meteorology
The precipitation characteristics that cause water-related disasters strongly depend on local factors such as topography. Therefore, high-resolution climate change projection data is needed to accurately assess regional flood disaster risk. Climate models generally have low resolution and are insufficient to reproduce observed precipitation distributions. Downscaling techniques are usually [...]
The debt burden of tropical cyclones and climate change
Published: 2026-01-29
Subjects: Earth Sciences, Environmental Studies, Natural Resource Economics, Sustainability
Addressing climate change, through both mitigation and adaptation, is anticipated to require global investments of more than $6 trillion annually by 2035. However, many countries face significant barriers to accessing the finance needed for these investments, due to low or absent credit ratings, large debt burdens, and high borrowing costs. There is concern that climate change, through its [...]
Compounding effects of hurricanes and marine heat waves in the Gulf of America
Published: 2026-01-29
Subjects: Oceanography
Exposure to extreme events is a primary concern for coastal regions where growing populations and stressed ecosystems are increasingly vulnerable. This study assesses the compounding effects of hurricanes and marine heatwaves (MHWs) in the Gulf of America. Using data from 1982 to 2024, we quantify MHWs through metrics of intensity, frequency, duration, and spatial extent, and examine their [...]
Systematic Review of Dissolved Oxygen in Streams and Rivers: Advances, Challenges, and Opportunities
Published: 2026-01-29
Subjects: Environmental Sciences, Terrestrial and Aquatic Ecology
Dissolved oxygen (DO) has been extensively studied in streams and rivers. Despite this breadth of research, the processes governing DO are rarely quantified concurrently with whole-ecosystem measurements. To address this gap, we synthesize 230 empirical studies (1964-2024) to evaluate how, where, and with what methods oxygen exchanges—the processes by which oxygen enters and leaves streams—have [...]