There are 2478 Preprints listed.
Published: 2021-08-30
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Quantitative characterization of subsurface properties is critical for many environmental applications and serves as the basis to simulate and better understand dynamic subsurface processes. Geophysical imaging methods allow to image subsurface property distributions and monitor their spatio-temporal changes in a minimally invasive manner. While it is widely agreed upon that models integrating [...]
Published: 2021-08-30
Subjects: Physical Sciences and Mathematics
New insights from Mars suggest crustal hydration contributed to the long-term drying of the planet. Three to four billion years ago, hydration of the Martian crust could have resulted from precipitation-driven surface weathering of mafic sediments, which on Earth leads to pedogenesis, i.e., the formation of soil. Although soil has been traditionally defined by its biological component, growing [...]
Published: 2021-08-30
Subjects: Earth Sciences, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology
A high-resolution climate projections dataset is obtained by statistically downscaling climate projections from the CMIP6 experiment using the ERA5-Land reanalysis from the Copernicus Climate Change Service. This global dataset has a spatial resolution of 0.1°x 0.1°, comprises 5 climate models and includes two surface daily variables at monthly resolution: air temperature and precipitation. Two [...]
Published: 2021-08-30
Subjects: Atmospheric Sciences, Climate
Extreme smog in India widely impacts air quality in late autumn and winter months. While the links between emissions and air quality are well-recognized, the association of smog and its intensification with climatic trends in the lower troposphere, where aerosol pollution and its radiative effects manifest, are not understood well. Here we use long-term satellite data to show a significant [...]
Published: 2021-08-30
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Tectonics and Structure
Geological heterogeneity is abundant in crustal fault zones; however, its role in controlling the mechanical behaviour of faults is poorly constrained. Here, we present laboratory friction experiments on laterally heterogeneous faults, with patches of strong, rate-weakening quartz gouge and weak, rate-strengthening clay gouge. The experiments show that the heterogeneity leads to a significant [...]
Published: 2021-08-27
Subjects: Geophysics and Seismology
The ability to estimate the likelihood of particular earthquake magnitudes occurring in a given region is critical for seismic hazard assessment. Earthquake size and recurrence statistics have been empirically linked to stress state, however there is ongoing debate as to which fault-zone processes are responsible for this link. We numerically model combined viscous creep and frictional sliding of [...]
Published: 2021-08-24
Subjects: Physical Sciences and Mathematics
Previous studies have suggested a link between rates of sea-level variation and eruptions globally [McGuire et al., 1997], with Satow and coauthors [2021] presenting the first detailed comparison between sea-level change and eruptive history for a single island-volcano. They use robust, high-resolution ages for volcanic deposits at Santorini, combined with a 2D numerical model to correlate [...]
Published: 2021-08-24
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The proliferation of dense arrays promises to improve our ability to image geological structures at the scales necessary for accurate assessment of seismic hazard. However, combining the resulting local high-resolution tomography with existing regional models presents an ongoing challenge. We developed a framework based on the level-set method that provides a means to infer where local data [...]
Published: 2021-08-24
Subjects: Applied Mechanics, Geophysics and Seismology, Partial Differential Equations, Tribology
The spectral boundary integral method is popular for simulating fault, fracture, and frictional processes at a planar interface. However, the method is less commonly used to simulate off-fault dynamic fields. Here we develop a spectral boundary integral method for poroelastodynamic solid. The method has two steps: first, a numerical approximation of a convolution kernel and second, an efficient [...]
Published: 2021-08-23
Subjects: Atmospheric Sciences, Meteorology
Fire-generated tornadic vortices (FGTVs) linked to pyrocumulonimbi (pyroCb) are a potentially deadly, yet poorly understood and seldom observed wildfire hazard. In this study we use radar and satellite observations to examine three FGTV cases during high impact wildfires during the 2020 fire season in California, USA. We establish that these FGTVs each exhibit tornado-strength anticyclonic [...]
Published: 2021-08-23
Subjects: Physical Sciences and Mathematics
Submarine landslides can generate complicated patterns of seafloor relief that influence subsequent flow behaviour and sediment dispersal patterns. While the large-scale morphology of submarine landslide deposits, or mass transport deposits (MTDs), can be resolved in seismic data, the nature of their upper surface, and its impact on facies distributions and stratal architecture of overlying [...]
Published: 2021-08-20
Subjects: Atmospheric Sciences, Engineering, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology, Oil, Gas, and Energy, Physical Sciences and Mathematics
Limiting emissions of climate-warming methane from oil and gas (O&G) is a major opportunity for short-term climate benefits. We deploy a basin-wide airborne survey of the New Mexico Permian Basin, spanning 35,923 km^2, 26,292 active wells, and over 15,000 km of natural gas pipelines using an independently-validated hyperspectral methane point source detection and quantification system. We [...]
Published: 2021-08-20
Subjects: Earth Sciences
The shift of armed conflicts to more urbanised environments has increased risk to cultural her-itage sites. Small arms impacts are ubiquitous in these circumstances, yet the effects and mecha-nisms of damage caused are not well known. A sandstone target was shot under controlled con-ditions to investigate surface and subsurface damage. A 3D model of the damaged block, created by structure from [...]
Published: 2021-08-20
Subjects: Environmental Monitoring, Longitudinal Data Analysis and Time Series
Time series reconstruction methods---used to generate gap-free time series of satellite observations---were historically designed for sensors with frequent image acquisitions. Since 2008, interest in leveraging time series methods has shifted from sensors such as AVHRR and MODIS to Landsat because of free, higher-resolution data availability and improved access to high-performance compute [...]
Published: 2021-08-20
Subjects: Oceanography
Subfootprint variability (SFV) is variability at a spatial scale smaller than the footprint of a sat-ellite, and cannot be resolved by satellite observations. It is important to quantify and understand as it contributes to the error budget for satellite data. The purpose of this study is to estimate the SFV for sea surface salinity (SSS) satellite observations. This is done using a [...]