Preprints
Filtering by Subject: Physical Sciences and Mathematics
Contributions of paleoecology to Easter Island’s prehistory: a thorough review
Published: 2020-07-22
Subjects: Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Life Sciences, Physical Sciences and Mathematics, Plant Sciences, Sustainability
Easter Island (Rapa Nui) is well known for the enigmas surrounding its unique megalithic statues, the moai, and the prehistoric (i.e., pre-European contact) Rapanui society that built them. These enigmas include, among others, the time of the island’s settlement, the geographical origin of the first settlers, the technology associated with moai transportation and emplacement, the occurrence (or [...]
Observing traveling waves in glaciers with remote sensing: New flexible time series methods and application to Sermeq Kujalleq (Jakobshavn Isbræ), Greenland
Published: 2020-07-22
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
The recent influx of remote sensing data provides new opportunities for quantifying spatiotemporal variations in glacier surface velocity and elevation fields. Here, we introduce a flexible time series reconstruction and decomposition technique for forming continuous, time-dependent surface velocity and elevation fields from discontinuous data and partitioning these time series into short- and [...]
Energetic Rupture and Tsunamigenesis during the 2020 Mw 7.4 La Crucecita, Mexico Earthquake
Published: 2020-07-21
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The La Crucecita earthquake ruptured on the megathrust generating strong shaking and a modest, long-lived tsunami. This is a significant earthquake that illuminates important aspects of the behavior of the megathrust as well as the potential related hazards. The rupture is contained within 15-30km depth, ground motions are elevated and the energy to moment ratio is high. We argue that it [...]
A general expression for wave-induced sediment bypassing of an isolated headland
Published: 2020-07-21
Subjects: Earth Sciences, Engineering, Geomorphology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Engineering, Physical Sciences and Mathematics
Accurate knowledge of the sediment budget of a coastal cell is necessary for coastal management and predicting long-term coastal change. An important component in the sediment budget of many wave-dominated embayed coastlines is the amount of sediment that bypasses rocky headlands, which present partial barriers to alongshore transport. Despite a recent surge in research interest in headland [...]
An Eddy-Zonal Flow Feedback Model for Propagating Annular Modes
Published: 2020-07-21
Subjects: Atmospheric Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The variability of the zonal-mean large-scale extratropical circulation is often studied using individual modes obtained from empirical orthogonal function (EOF) analyses. The prevailing reduced-order model of the leading EOF (EOF1) of zonal-mean zonal wind, called the annular mode, consists of an eddy-mean flow interaction mechanism that results in a positive feedback of EOF1 onto itself. [...]
How Extreme Weather Events Are Attributed to Anthropogenic Global Warming
Published: 2020-07-20
Subjects: Environmental Indicators and Impact Assessment, Environmental Sciences, Physical Sciences and Mathematics
Many politicians and media personalities continue to cast doubt on the idea that anthropogenic global warming (AGW) – the primary driver of current global climate change – could possibly be behind the growing frequency and severity of extreme weather events – the droughts, heatwaves, flooding, etc. that are every year breaking 100 year or greater historical records. This takes the form not just [...]
Navigating groundwater model uncertainty analysis
Published: 2020-07-20
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
The design of a groundwater model is based on the model objective, the management or research question that the model seeks to address. Designing the uncertainty analysis of a groundwater models likewise needs to consider the objective of the uncertainty analysis; how the uncertainty in model predictions will be used. In this paper a framework is presented to consider the various dimensions of [...]
Stress perturbations from hydrological and industrial loads and seismicity in the Salt Lake City region
Published: 2020-07-18
Subjects: Earth Sciences, Other Earth Sciences, Physical Sciences and Mathematics
The March 18, 2020 M5.7 Magna earthquake awakened people from decades of seismic quiescence in Salt Lake City, Utah. The event occurred just east of a mine tailings impoundment that receives ~60 million tons/yr of ore waste products since the early 1900s. Here we investigate elastic loading effects due to the anthropogenic mass transfer and various natural hydrological loads. We note a possible [...]
Adopting deep learning methods for airborne RGB fluvial scene classification.
Published: 2020-07-18
Subjects: Environmental Monitoring, Environmental Sciences, Physical Sciences and Mathematics
River environments are among the world’s most threatened ecosystems. Enabled by the rapid development of drone technology, hyperspatial resolution (<10 cm) images of fluvial scenes are now a common data source used to better understand these sensitive habitats. However, the task of image classification remains challenging for this type of imagery and the application of traditional [...]
Sedimentary structures discriminations with hyperspectral imaging on sediment cores
Published: 2020-07-17
Subjects: Analytical Chemistry, Chemistry, Earth Sciences, Environmental Chemistry, Environmental Monitoring, Environmental Sciences, Multivariate Analysis, Optics, Physical Sciences and Mathematics, Physics, Sedimentology, Statistical Models, Statistics and Probability
Hyperspectral imaging (HSI) is a non-destructive high-resolution sensor, which is currently under significant development to analyze geological areas with remote devices or natural samples in a laboratory. In both cases, the hyperspectral image provides several sedimentary structures that need to be separated to temporally and spatially describe the sample. Sediment sequences are composed of [...]
dragon: A New Tool for Exploring Redox Evolution Preserved in the Mineral Record
Published: 2020-07-16
Subjects: Biogeochemistry, Earth Sciences, Physical Sciences and Mathematics
The flow of energy and elements between the geosphere and biosphere can be traced through changing redox chemistry of Earth’s surface. Deep-time trends in the mineral record, including mineral age and elemental composition, reveal a dynamic history of changing redox states and chemical speciation. We present a user-friendly exploratory network analysis platform called dragon (Deep-time Redox [...]
Whats down there? The structures, materials and environment of deep-seated tremor and slip
Published: 2020-07-16
Subjects: Earth Sciences, Geochemistry, Geology, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
Episodic tremor and slow slip (ETS) events occur downdip of the seismogenic zone of numerous subduction megathrusts and plate boundary strike-slip faults. These events represent a fascinating and perplexing mode of fault failure that has greatly broadened our view of earthquake dynamics. In this contribution, we review constraints on the ETS deformation process from both geophysical observations [...]
Modelling an energetic tidal strait: investigating implications of common numerical configuration choices
Published: 2020-07-16
Subjects: Applied Mathematics, Civil and Environmental Engineering, Civil Engineering, Engineering, Numerical Analysis and Computation, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Characterising tidal hydrodynamics in the vicinity of submerged features can be demanding given the hostility of the marine environment. Logistical challenges in the measurement of such flows has promoted research on wake studies through physical and numerical modelling. In this study, site measurements and modelled data are combined to provide an insight into the regional hydrodynamics within a [...]
Principles of Shortening in Salt Basins Containing Isolated Minibasins
Published: 2020-07-16
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
Shortening styles in salt-influenced basins can vary markedly, with the volume and distribution of salt prior to shortening being a key control. Here we use a suite of physical models to examine styles of thin-skinned regional shortening in settings where the pre-shortening structure comprised minibasins surrounded by salt (‘isolated-minibasin’ provinces). Our models show that the high volume of [...]
Frequent Mass Movements from Glacial and Lahar Terraces, Controlled by Both Hillslope Characteristics and Fluvial Erosion, are an Important Sediment Source to Puget Sound Rivers
Published: 2020-07-16
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Mass movements from glacial and lahar terraces in the middle and lower reaches of rivers draining the Washington Cascade Range to Puget Sound may represent a substantial portion of those rivers’ sediment supply and pose significant mass movement hazards. However, the quantitative importance of this sediment source is unknown, and the magnitudes, spatial distribution, styles, and controls of these [...]