Preprints
There are 6976 Preprints listed.
Model Parameter Evaluation and Improvement for Real-Time Flood Inundation Mapping Using HAND Model: Iowa Case Study
Published: 2020-07-01
Subjects: Civil and Environmental Engineering, Engineering, Hydraulic Engineering
In this study, the performance of Height Above Nearest Drainage (HAND) was evaluated in Linn, Jones, Johnson, Cedar, and Muscatine counties in the State of Iowa. The impacts of three model parameters (drainage threshold, water depth, resolution of data) were studied. The effectiveness of improving approaches—variable water depths, community-level analysis, and inner zone was explored. The model [...]
Tidal Modulation of Antarctic Ice Shelf Melting
Published: 2020-07-01
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
Tides influence basal melting of individual Antarctic ice shelves, but their net impact on Antarctic-wide ice-ocean interaction has yet to be constrained. Here we quantify the impact of tides on ice shelf melting and the continental shelf seas by means of a 4 km resolution circum-Antarctic ocean model. Activating tides in the model increases the total basal mass loss by 57 Gt/yr (4 %), while [...]
“Empirical pre-whitening” spectral analysis detects periodic but inconsistent signals in abyssal hill morphology at the southern East Pacific Rise
Published: 2020-07-02
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
The existence, or not, of periodicities in abyssal hill morphology has been vigorously debated in recent publications, and some have hypothesized that such periodicities are evidence of the impact of Milankovitch cycle-caused sea level fluctuations on the volcanic construction process at mid-ocean ridges. Periodicities are detected by the presence of spectral peaks that rise significantly above [...]
Adjoint-based sensitivity analysis for a numerical storm surge model
Published: 2020-06-29
Subjects: Applied Mathematics, Numerical Analysis and Computation, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Numerical storm surge models are essential to forecasting coastal flood hazard and informing the design of coastal defences. However, such models rely on a variety of inputs, many of which will carry uncertainty, and an awareness and understanding of the sensitivity of the model outputs with respect to those uncertain inputs is necessary when interpreting model results. Here, we use an [...]
A comparison of Bayesian inference and gradient-based approaches for friction parameter estimation
Published: 2020-06-29
Subjects: Applied Mathematics, Numerical Analysis and Computation, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Numerical tidal models are essential to the study of a variety of coastal ocean processes, but typically rely on uncertain inputs, including a bottom friction parameter which can in principle be spatially varying. Here we employ an adjoint-capable numerical ocean model, Thetis, and apply it to the Bristol Channel and Severn Estuary, using a spatially varying Manning coefficient within the bottom [...]
An agent-based model for estimating emissions reduction equivalence among leak detection and repair programs
Published: 2020-07-02
Subjects: Environmental Sciences, Oil, Gas, and Energy, Physical Sciences and Mathematics
Alternative leak detection and repair (alt-LDAR) programs are being introduced by regulators in North America to provide flexibility in how oil and gas producers manage their fugitive methane emissions. However, emissions reduction equivalence must be established between a proposed program and a regulatory standard. We present LDAR-Sim, an open-source, agent-based numerical model for estimating [...]
Seismic swarm preceding the 2017 Mount Agung eruption in Bali (Indonesia) enhanced by the matched filter approach
Published: 2020-07-02
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Intense swarm seismicity took place before the 2017 Mount Agung eruption in Bali (Indonesia). However, the earthquake sequences were not well documented. In addition, there was a substantial delay between the peak of the seismic activity (late September) and the onset of the impending eruption (late November). We applied waveform-based hypocenter relocation and matched filter technique (MFT) to [...]
Seismological Expression of the Iron Spin Crossover in Ferropericlase in the Earth’s Lower Mantle
Published: 2020-06-29
Subjects: Earth Sciences, Geochemistry, Geophysics and Seismology, Mineral Physics, Physical Sciences and Mathematics, Physics, Quantum Physics, Tectonics and Structure
The two most abundant minerals on Earth which together make up over 90% of the Earth’s lower mantle are (Mg,Fe)O-ferropericlase (Fp) and (Mg,Fe)SiO3-bridgmanite (Bm). Iron in Fp undergoes a high-spin to low-spin (HS-LS) crossover that influences density, viscosity, elasticity, thermal conductivity, and elemental partitioning, however, the predicted effects of this transition are not apparent in [...]
Fully Automated Carbonate Petrography Using Deep Convolutional Neural Networks
Published: 2020-06-23
Subjects: Artificial Intelligence and Robotics, Computer Sciences, Earth Sciences, Geology, Paleobiology, Paleontology, Physical Sciences and Mathematics, Sedimentology
Carbonate rocks are important archives of past ocean conditions as well as hosts of economic resources such as hydrocarbons, water, and minerals. Geologists typically perform compositional analysis of grain, matrix, cement and pore types in order to interpret depositional environments, diagenetic modification, and reservoir quality of carbonate strata. Such information can be obtained primarily [...]
Terrestrial evaporation and global climate: lessons from Northland, a planet with a hemispheric continent
Published: 2020-06-22
Subjects: Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
From a climate perspective, land differs from the ocean in several fundamental physical ways, including albedo, heat capacity, amount of water storage, and differences in resistance to evaporation. These differences alter the surface energy and water budgets over land compared to ocean, with implications for both surface climate and atmospheric circulation. In this study, we use an idealized [...]
Excessive seismicity over a limited source: the August 2019 earthquake swarm near Mt. Salak in West Java (Indonesia)
Published: 2020-06-22
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The triggering mechanism of swarm-like seismicity in the Java Island of Indonesia is generally not well understood. Understanding earthquake swarm phenomena and monitoring in various tectonic settings can be improved by the detection of micro-earthquakes; however, such a catalog is not available due to various reasons including the existing limited seismic network and using an outdated algorithm [...]
Epitomic Data for Community Land Model Standalone Simulations for Prognostic Analyses of Tropical Mountain Glaciation and Lake Temperature in Pre-Industrial, Last Glacial Maximum, and Extreme Glacial Climates
Published: 2022-11-15
Subjects: Climate, Fresh Water Studies, Glaciology, Hydrology
Global climate models typically simulate climate at much larger spatial scales than tropical mountain glaciers and many of the world’s lakes. Yet some of the proxy data that can be used to validate models of past climate on land come from and are related to these geographic features. Validating global climate models using these proxies requires some method of downscaling global climate model [...]
A Review of Satellite Remote Sensing Techniques of River Delta Morphology Change
Published: 2020-06-22
Subjects: Earth Sciences, Environmental Monitoring, Environmental Sciences, Geomorphology, Physical Sciences and Mathematics
River deltas are important coastal depositional systems that are home to almost half a billion people worldwide. Understanding morphology changes in deltas is important in identifying vulnerabilities to natural disasters and improving sustainable planning and management. Satellite remote sensing has shown to be a useful technology for analyzing these morphology changes owing largely to its [...]
Rates of olivine grain growth during dynamic recrystallization and post-deformation annealing
Published: 2020-06-23
Subjects: Earth Sciences, Geology, Mineral Physics, Physical Sciences and Mathematics, Tectonics and Structure
We performed deformation and grain growth experiments on natural olivine aggregates with moderate olivine water contents (COH = 600±300 ppm H/Si) at 1000-1200°C and a confining pressure of 1400±100 MPa. Our experiments differ from published grain growth studies in that most were: 1) conducted on natural olivine cores rather than hot-pressed aggregates, and 2) dynamically recrystallized prior to [...]
Modelling massive AIS streams with quad trees and Gaussian Mixtures
Published: 2020-06-29
Subjects: Computer Sciences, Other Computer Sciences, Physical Sciences and Mathematics
Pressing issues related to the movement of people and goods can be tackled today thanks to improvements in tracking and communications technology that have made it possible to collect movement data on a big scale. Maritime data from the Automatic Identification System (AIS) is one of the fast growing sources of movement data. Existing approaches for AIS data [...]