Preprints
There are 5428 Preprints listed.
Assisted upscaling of miscible CO¬2-enhanced oil recovery floods using an artificial-neural-network-based optimisation algorithm
Published: 2023-07-13
Subjects: Engineering, Other Engineering
The fine-scale compositional simulations required to accurately model miscible CO2 flooding are unrealistic and highly computationally expensive, and upscaling procedures are required to approximate the behaviour of these fine-scale grids on more realistic coarse-scale models. These procedures include the pseudoisation of relative permeabilities which ensures the matching of large-scale effects [...]
Nutrient concentrations and nitrogen speciation in tropical watersheds of central Panama
Published: 2023-07-13
Subjects: Environmental Sciences
We present chemical analyses from rivers and streams in five partly to near-fully forested watersheds in the humid tropics of central Panama. Contrary to the situation observed for temperate watersheds in the Northern Hemisphere, the concentration of dissolved inorganic nitrogen in the Panamanian watersheds is low (mostly <2.6 µmol L-1), whereas concentrations of organic nitrogen are several [...]
Recent increase in a recurrent pan-Atlantic wave-pattern driving concurrent wintertime extremes
Published: 2023-07-13
Subjects: Physical Sciences and Mathematics
Wintertime extremes such as cold spells and heavy precipitation can have severe socioeconomic impacts, disrupting critical infrastructures and affecting human wellbeing. Here, we relate the occurrence of local and concurrent cold or wet wintertime extremes in North America and Europe to a recurrent, quasi-hemispheric wave-4 Rossby wave pattern. We identify this pattern as a fundamental mode of [...]
The interactions of instabilities during miscible CO2 enhanced oil recovery: A numerical simulation study
Published: 2023-07-13
Subjects: Petroleum Engineering, Transport Phenomena
During field-scale simulations of miscible displacements, the effect of heterogeneity-induced channelling is always accounted for, while micro-scale physical instabilities like viscous fingering and molecular diffusion are ignored due to the computational costs of the required fine-grid simulations. Thus, the interplay between small- and macro-scale physical instabilities is not properly [...]
An Artificial Neural Network to Estimate the Foliar and Ground Cover Input Variables of the Rangeland Hydrology and Erosion Model
Published: 2023-07-12
Subjects: Artificial Intelligence and Robotics, Environmental Monitoring, Hydrology, Natural Resources and Conservation, Natural Resources Management and Policy, Soil Science
Models like the Rangeland Hydrology and Erosion Model (RHEM) are useful for estimating soil erosion, however, they rely on input parameters that are sometimes difficult or expensive to measure. Specifically, RHEM requires information about foliar and ground cover fractions that generally must be measured in situ, which makes it difficult to use models like RHEM to produce erosion or soil risk [...]
Techno-economic evaluation of the potential of CO2 storage and Enhanced Oil Recovery in the Niger-Delta Hydrocarbon Basin using reservoir simulation: Case Study
Published: 2023-07-12
Subjects: Engineering, Other Engineering
The constant dependence on fossil fuel combustion for energy and industrial activities results in global warming and climate change due to the increased atmospheric concentration of greenhouse gases such as CO2. CO2 storage in mature petroleum reservoirs is considered one of the most viable ways to reduce CO2 concentrations in the atmosphere. The Niger-Delta hydrocarbon basin holds significant [...]
Discovery of a new 12-km impact crater candidate at As Sail Al Kabeer, Saudi Arabia
Published: 2023-07-11
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Planetary Geology, Planetary Sciences
The Arabian shield of Saudi Arabia likely has many impact craters due to the old age of its rocks, however many of them have not yet been discovered due to their resemblance to plutons. Using satellite imagery, a 12-km wide circular structure with a central peak was identified at As Sail Al Kabeer, 40 kilometers north of the city of Taif in western Saudi Arabia. Fieldwork has shown that this [...]
Electric Circuit Theory as a method for monitoring tree water deficit at different scales
Published: 2023-07-11
Subjects: Forest Biology, Forest Sciences, Other Forestry and Forest Sciences
Climate change is expected to alter precipitation patterns, making droughts more frequent in some areas, which will expose trees to more severe water deficits which could result in the catastrophic collapse of their water transport system and, eventually, mortality. To inform forest management and tree species suitability to increase forest resilience requires a robust method for understanding [...]
Earth System Data Cubes: Avenues for advancing Earth system research
Published: 2023-07-11
Subjects: Computer Sciences, Earth Sciences, Environmental Sciences
Recent advancements in Earth system science have been marked by the exponential increase in the availability of diverse, multivariate datasets characterised by moderate to high spatio-temporal resolutions. Earth System Data Cubes (ESDCs) have emerged as one suitable solution for transforming this flood of data into a simple yet robust data structure. ESDCs achieve this by organising data into an [...]
A high-resolution, 3D groundwater-surface water simulation of the contiguous US: Advances in the integrated ParFlow CONUS 2.0 modeling platform
Published: 2023-07-10
Subjects: Engineering
Large-scale, high-resolution hydrologic modeling is an important tool to address questions of water quantity, availability, and recharge. Continental-to-Global scale models, particularly those that include groundwater, are growing in number. However, many of these approaches simplify aspects of the system and the connections between e.g., surface water and groundwater. The ParFlow CONUS modeling [...]
Satellite-derived shorelines for monitoring of sandy beaches: a benchmark study
Published: 2023-07-10
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Engineering, Geomorphology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Earth Sciences, Physical Sciences and Mathematics
Satellite remote sensing is becoming a widely used monitoring technique in coastal sciences. Yet, no benchmarking studies exist that compare the performance of popular satellite-derived shoreline (SDS) mapping algorithms against standardized sets of inputs and validation data. Here we present a new benchmarking framework to evaluate the accuracy of shoreline change observations extracted from [...]
Projecting Future Heat Stress Disparities to 2100 in the Contiguous United States
Published: 2023-07-09
Subjects: Social and Behavioral Sciences
Global warming increases health risks from heat exposure. Historical evidence suggests disproportionate impacts of heat exposure in different regions across socioeconomic groups in the US. However, little is known about the scale of potential disparities and which populations stand to be most vulnerable under different future climate scenarios. Here, we assess county-level heat exposure, measured [...]
Mitigation effectiveness on groundwater-dependent ecosystems revealed by counterfactual AI
Published: 2023-07-09
Subjects: Artificial Intelligence and Robotics, Environmental Engineering, Hydrology, Sustainability, Water Resource Management
Overexploitation of groundwater threatens groundwater-bound aquatic and terrestrial biodiversity and ecosystem stability, underscoring the need to devise appropriate mitigation strategies. Yet, substantial scientific evidence that mitigation measures effectively protect groundwater ecosystems is presently nonexistent. We provide unique and compelling evidence, using counterfactual artificial [...]
Heuristic Data-inspired Scheme to Characterize Meteorological and Groundwater Droughts in Semi-arid Karstic Region under Warming Climate
Published: 2023-07-09
Subjects: Environmental Engineering, Environmental Indicators and Impact Assessment, Hydrology
Study region The Edwards Aquifer Region is located in south-central Texas, United States. Study focus The paper focuses on the development and implementation of a data-inspired heuristic drought identification scheme to (i) quantify the intensity, duration, and frequency of precipitation deficit- and high temperature-driven meteorological droughts (PMet- and TMet-droughts), and (ii) link [...]
Optimising the value of a CO2 Water-Alternating-Gas injection project under geological and economic uncertainties using an improved artificial neural network.
Published: 2023-07-09
Subjects: Engineering, Other Engineering
The numerical simulations required for the robust optimisation of the alternating injection of water and CO2 in hydrocarbon reservoirs are computationally expensive due to engineering, geological, and economic uncertainties. Using approximation models of the desired objective function(s) can significantly decrease the cost associated with the optimisation routines while providing an adequate [...]