Preprints
There are 5166 Preprints listed.
Cambrian foreland phosphogenesis in the Khuvsgul Basin of Mongolia
Published: 2024-12-27
Subjects: Earth Sciences, Geochemistry, Geology, Sedimentology, Stratigraphy, Tectonics and Structure
Ediacaran-Cambrian phosphorite deposits in northern Mongolia have been associated with a putative increase in nutrient delivery to the global oceans that drove oxygenation and the rise of animals. However, like many phosphorites from this ~130 Myr interval, the precise age and depositional setting of these deposits remain poorly constrained. Here, we integrate new geological mapping, [...]
AI-Driven Decision-Making for Water Resources Planning and Hazard Mitigation Using Automated Multi Agents
Published: 2024-12-27
Subjects: Civil Engineering, Computational Engineering, Computer and Systems Architecture, Computer Engineering, Ecology and Evolutionary Biology, Education, Engineering, Environmental Engineering, Geotechnical Engineering, Higher Education, Hydraulic Engineering, Operations Research, Systems Engineering and Industrial Engineering, Risk Analysis, Scholarship of Teaching and Learning, Systems Engineering, Terrestrial and Aquatic Ecology, Transportation Engineering
This project simulates the Multi-Hazard Tournament (MHT) framework, a decision support system designed for the U.S. Army Corps of Engineers, using AI agents to enhance decisionmaking processes for flood mitigation and water resource management. The objective of the framework is to develop optimal strategies for protecting water resources, habitats, and communities within a defined budget. The [...]
A 3D Darcy-scale reactive transport modeling of experimental wormhole formation in limestone under geological CO2 storage conditions
Published: 2024-12-27
Subjects: Transport Phenomena
Geologic CO2 storage is projected to play a key role in mitigating the climate change crisis. Changes in pore structure and hydraulic properties are likely to occur in carbonate rocks when they interact with CO2 as an acid-producing agent, potentially affecting CO2 flow and storage behavior in the subsurface. Here, we combine laboratory experiments and numerical simulations of CO2-saturated water [...]
Variation of climate and its temporal shifts across an altitudinal gradient of tropical rainforests of Sri Lanka
Published: 2024-12-26
Subjects: Forest Sciences
Climate and its variability strongly influence the structure and dynamics of tropical rainforests, a biome which is critical for regulation of the global climate. We characterized the climate of a series of rainforest plots in Sri Lanka across a wide altitudinal range (117 to 2132 m above sea level) during 1990-2018 and determined its temporal shifts from the climate of 1961-1989. Long-term [...]
Approach to setting the attribution of CO2 reductions for CCU fuels — Toward a system counting fuel selection as an emission reduction effort
Published: 2024-12-26
Subjects: Environmental Studies
As the global economy transitions towards carbon neutrality, innovative secondary energy sources are becoming increasingly pivotal. Hydrogen derived from zero-carbon power and synthetic fuels produced by bonding carbon dioxide (CO2) with hydrogen—hereafter referred to as Carbon Capture and Utilisation (CCU) fuels in this article—are expected to complement electricity as critical components in [...]
Emulator-based Bayesian calibration of a subglacial drainage model
Published: 2024-12-25
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
Subglacial drainage models, often motivated by the relationship between hydrology and ice flow, sensitively depend on numerous unconstrained parameters. We explore using borehole water-pressure timeseries to calibrate the uncertain parameters of a popular subglacial drainage model, taking a Bayesian perspective to quantify the uncertainty in parameter estimates and in the calibrated model [...]
Beyond fractures: the role of bedding planes in fluid flow pathways within a well-bedded carbonate sequence
Published: 2024-12-24
Subjects: Earth Sciences, Physical Sciences and Mathematics
Conventionally, subsurface fluid flow modelling studies have concentrated on the characterization of fracture networks and their capacity to facilitate vertical and lateral fluid movements. This study utilizes unique field observations of oxidation halos in a well-bedded carbonate sequence in the Paris Basin, France, offering new perspectives on fluid flow pathways. It demonstrates that, in [...]
Improved Streamflow Simulations in Hydrologically Diverse Basins using Physically Informed Deep Learning Models
Published: 2024-12-23
Subjects: Civil Engineering, Engineering, Hydrology
Physically informed deep learning models, especially Long Short-Term Memory (LSTM) networks, have shown promise in large-scale streamflow simulations. However, an in-depth understanding of the relative contribution of physical information in deep learning models has been missing. Using a large-sample testbed of 220 catchments in hydrologically diverse regions of the Indian subcontinent, we [...]
An environmental modeling algorithm to predict naturalized hydrology and water allocation status at human-influenced gauged sites: case study, Otago New Zealand
Published: 2024-12-22
Subjects: Physical Sciences and Mathematics
Recent New Zealand legislation requires that regional councils set limits for water resource usage to manage the effects of abstractions in over-allocated catchments. Toward that end, an environmental modeling algorithm is proposed and demonstrated for applicability to sustainable stream management across the Otago Region of New Zealand. This four-layer algorithm includes a Data model, Base [...]
Preliminary Development of Machine Learning Emulators for Long-Term Atmospheric CO2 Evolution
Published: 2024-12-22
Subjects: Atmospheric Sciences, Biogeochemistry, Climate, Environmental Chemistry, Physical Sciences and Mathematics
This study evaluates machine learning emulators for modeling long-term atmospheric CO2 evolution by comparing Random Forests (RF) and Multilayer Perceptrons (MLP) in replicating cGENIE Earth System Model outputs over a one-million-year timescale. Using one-year pulse emission experiments spanning 1,000-20,000 PgC with outputs tracked for 106 years, we assessed emulator performance across multiple [...]
Unlocking Geological Hydrogen Storage with Ammonia: An Effort for Net-Zero Future
Published: 2024-12-21
Subjects: Education, Engineering
Hydrogen gas (H2) generation systems, comprising carbon capture and storage technology (CCST) play a crucial role to achieve the U.N. Net Zero goal before 2050. However, a critical challenge in grid-scale H2 storage is the low volumetric energy density. One prospective approach is to use ammonia (NH3) as a chemical carrier for H2 and store it. This paper presents a state-of-the-art report on NH3 [...]
Quantifying the benefits of nature-based solutions in urban drainage on headwater stream water quality
Published: 2024-12-21
Subjects: Terrestrial and Aquatic Ecology
In urban areas lacking adequate sanitation infrastructure, greywater flows into nearby urban streams through the stormwater drainage network. This study evaluates the impact of this drainage on water quality in a headwater stream in the Metropolitan Area of Buenos Aires (AMBA), Argentina. We analysed and model pollutant loads — organic matter, nutrients, and allochthonous faecal bacteria — [...]
Efficacy of Recent Prescribed Burning and Land Management on Wildfire Burn Severity and Smoke Emissions in the Western United States
Published: 2024-12-21
Subjects: Environmental Sciences
Prescribed fire is increasingly proposed as a policy strategy to reduce wildfire risks, but evidence of its effectiveness in lowering fire severity and smoke emissions remains limited in the western US. We empirically demonstrate that areas treated with prescribed fire and subsequently burned during California’s extreme 2020 wildfire season showed a -14% net reduction in smoke emissions, though [...]
Global drivers of forest loss at 1 km resolution
Published: 2024-12-20
Subjects: Computer Sciences, Environmental Sciences, Geographic Information Sciences, Remote Sensing
Forests are in decline worldwide due to human activities such as agricultural expansion, urbanization, and mineral extraction. Forest loss due to generally temporary causes, such as wildfire and forest management, is important to distinguish from permanent land use conversion due to the differing ecological and climate impacts of these disturbances and for the purposes of developing effective [...]
Heat Vulnerability Analysis And Mapping (HEVAM): Analysis of United States power grids vulnerability to climate changes
Published: 2024-12-20
Subjects: Civil and Environmental Engineering, Electrical and Computer Engineering, Environmental Engineering, Power and Energy
The importance of the power grid under the energy sector umbrella is difficult to overstate, as it enables the function of nearly all critical infrastructure systems. The interconnected assets within electrical substations enable the function of our society and economy. With such a vast system of interconnected nodes, threats to the stability of this network come in many forms, from natural [...]