Preprints
There are 4717 Preprints listed.
Commercial-Scale Demonstration of a First-of-a-Kind Enhanced Geothermal System
Published: 2023-07-18
Subjects: Engineering, Physical Sciences and Mathematics
Fervo Energy has completed construction of a commercial enhanced geothermal system (EGS) project and has qualified full functionality of the system through production testing at commercially relevant operating conditions. The project site is located in a nearfield setting adjacent to an operating geothermal power station in north-central Nevada and is designed to deliver an uplift in [...]
Waterflood-CMG production optimization analysis for the Draugen field of Norway
Published: 2023-07-18
Subjects: Engineering
The Draugen field is well-known for producing oil that is then transported to power plant facilities to generate electricity in Draugen. However, with declining oil production (as of 2021) and new necessary electrification contracts, the field may be unable to meet the demand for plant facilities. The current study combines waterflooding and reservoir simulation methods from the Computer [...]
Separating Internal and Forced Contributions to Near Term SST Predictability in the CESM2-LE
Published: 2023-07-17
Subjects: Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology
An open question in the study of climate prediction is whether internal variability will continue to contribute to prediction skill in the coming decades, or whether predictable signals will be overwhelmed by rising temperatures driven by anthropogenic forcing. We design an interpretable neural network that can be decomposed to examine the relative contributions of external forcing and internal [...]
Climate Resilience of small-town water utilities in Eastern Ethiopia
Published: 2023-07-14
Subjects: Environmental Sciences
Building a resilient water, sanitation, and hygiene (WASH) system is more important than ever since climate change threatens WASH, particularly in low- and middle-income countries. The Government of Ethiopia stresses climate-resilient WASH through its One WASH National Program, albeit it may be challenging to ascertain the resilience due to the absence of an easy-to-use monitoring tool. The “How [...]
Regenerative Agriculture the Veganic Way: A Seven-year Research Study in Increasing Soil Organic Matter (SOM) and Crop Yields
Published: 2023-07-14
Subjects: Agriculture
Agriculture is a major contributor to greenhouse gas (GHG) emissions and biodiversity loss, mostly through deforestation for the cultivation of animal feeds; enteric fermentation from ruminants like cattle, fertilizers and manure; and soil degradation from intensive farming practices. There is currently a push to transform our farming systems to attempt to alleviate the almost-assured [...]
Integrating Climate Risk into Long-Term Energy Planning: A Critical Review
Published: 2023-07-14
Subjects: Civil Engineering, Earth Sciences, Power and Energy, Risk Analysis
Electricity systems face substantial and growing climate risks which are escalating due to electrification, renewable energy intermittency, population changes, and the intensifying impacts of climate change such as extreme temperatures and weather-induced infrastructure damage. This critical review investigates climate risks to the electricity sector and scrutinizes the methodologies used to [...]
Last Glacial Maximum pattern effects reduce climate sensitivity estimates
Published: 2023-07-13
Subjects: Atmospheric Sciences, Climate, Oceanography, Oceanography and Atmospheric Sciences and Meteorology
Here, we show that the Last Glacial Maximum (LGM) provides a stronger constraint on equilibrium climate sensitivity (ECS), the global warming from increasing greenhouse gases, after accounting for temperature patterns. Feedbacks governing ECS depend on spatial patterns of surface temperature (“pattern effects”); hence, using the LGM to constrain future warming requires quantifying how [...]
CLIMATIC DETERMINANTS OF COVID-19 CASES AND DEATHS IN UGANDA: 2020-2022
Published: 2023-07-13
Subjects: Risk Analysis
Background: Infectious diseases have proven to be among the greatest challenges to life in the Anthropocene era. Their repeated and cyclical occurrences coupled with varying variants, and rapidly changing climatic conditions within this century threaten to take the world back to the “pre-development era” in the absence of corrective measures. We designed a research study to determine the [...]
A deep learning approach for deriving winter wheat phenology from optical and SAR time series at field level
Published: 2023-07-13
Subjects: Agricultural Science, Agriculture, Artificial Intelligence and Robotics, Environmental Monitoring
Information on crop phenology is essential when aiming to better understand the impacts of climate and climate change, management practices, and environmental conditions on agricultural production. Today’s novel optical and radar satellite data with increasing spatial and temporal resolution provide great opportunities to provide such information. However, so far, we largely lack methods that [...]
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 [...]