Preprints
Filtering by Subject: Earth Sciences
The Glacial Origins of Relict Pingos, Wales, UK
Published: 2019-07-04
Subjects: Earth Sciences, Geomorphology, Glaciology, Physical Sciences and Mathematics
Ramparted depressions (doughnut-shaped debris-cored ridges with peat- and/or sediment-filled central basins) are commonly perceived to represent the relict collapsed forms of permafrost ground-ice mounds (i.e. pingos or lithalsas). In Wales, UK, ramparted depressions of Late Pleistocene age have been widely attributed to permafrost-related processes. However, a variety of alternative glacial [...]
From prodigious volcanic degassing to caldera subsidence and quiescence at Ambrym (Vanuatu): the influence of regional tectonics
Published: 2019-06-28
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure, Volcanology
Eruptive activity shapes volcanic edifices. The formation of broad caldera depressions is often associated with major collapse events, emplacing conspicuous pyroclastic deposits. However, caldera subsidence may also proceed silently by magma withdrawal at depth, more difficult to detect. Ambrym, a basaltic volcanic island, hosts a 12-km wide caldera and several intensely-degassing lava lakes [...]
Certified Reduced Basis Method in Geosciences Addressing the challenge of high dimensional problems
Published: 2019-06-28
Subjects: Applied Mathematics, Earth Sciences, Numerical Analysis and Computation, Partial Differential Equations, Physical Sciences and Mathematics
One of the biggest challenges in Computational Geosciences is finding ways of efficiently simulating high-dimensional problems. In this paper, we demonstrate how the RB method can be gainfully exploited to solve problems in the Geosciences. The reduced basis method constructs low-dimensional approximations to (high-dimensional) solutions of parametrized partial differential equations. In contrast [...]
What sets the width of a river?
Published: 2019-06-28
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Alluvial rivers are formed by, and are an expression of, the water and sediment that they convey. They are the primary arteries of water and nutrients on land, making them the lifeblood of communities and commerce. While a myriad of environmental and geological factors have been proposed to control alluvial river size, near-universal scaling relations between channel geometry and discharge [...]
Increasing dependence of lowland population on mountain water resources
Published: 2019-06-28
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Mountain areas provide disproportionally high runoff in many parts of the world, but their importance for lowland water resources and food production has not been clarified so far. Here we quantify for the first time the extent to which lowland inhabitants potentially depend on runoff contributions from mountain areas (39% of land mass). We show that ~1.4 billion people (23% of world’s lowland [...]
Lateral variability of shelf-edge, slope and basin-floor deposits, Santos Basin, offshore Brazil
Published: 2019-06-28
Subjects: Earth Sciences, Engineering, Geology, Physical Sciences and Mathematics, Sedimentology
Construction of continental margins is driven by sediment transported across the shelf to the shelf-edge, where it is reworked by wave-, tide- and river-influenced processes within deltas and flanking clastic shorelines. Stalling of continental margin progradation often results in degradation of the outer shelf to upper slope, with re-sedimentation to the lower slope and basin-floor via a range [...]
More hots: Quantifying upward trends in the number of extremely hot days and nights in Tallahassee, Florida, USA: 1892–2018
Published: 2019-06-27
Subjects: Earth Sciences, Physical Sciences and Mathematics
The U.S. National Weather Service Office (WSO) Tallahassee official record shows an upward trend in the number of hot days at a rate of 2.1% per year and a more pronounced upward trend in the number of hot nights at a rate of 4.5% per year. Increasingly frequent hot days and nights result from more and longer hot events (consecutive hot days/nights).
Dynamical Systems Theory Sheds New Light on Compound Climate Extremes in Europe and Eastern North America
Published: 2019-06-27
Subjects: Applied Mathematics, Atmospheric Sciences, Climate, Dynamic Systems, Earth Sciences, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Physics, Statistical, Nonlinear, and Soft Matter Physics
We propose a novel approach to the study of compound extremes, grounded in dynamical systems theory. Specifically, we present the co-recurrence ratio (α), which elucidates the dependence structure between variables by quantifying their joint recurrences. This approach is applied to daily climate extremes, derived from the ERA-Interim reanalysis over the 1979-2018 period. The analysis focuses on [...]
Snow Depth and Snow Water Equivalent Estimation in the Northwestern Himalayan Watershed using Spaceborne Polarimetric SAR Interferometry
Published: 2019-06-27
Subjects: Earth Sciences, Engineering, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Water Resource Management
Snow depth (SD) and Snow Water Equivalent (SWE) constitute essential physical properties of snow and find extensive usage in the hydrological modelling domain. However, the prominent impact of the hydrometeorological conditions and difficult terrain conditions inhibit accurate measurement of the SD and SWE— an ongoing research problem in the cryosphere paradigm. In this context, spaceborne [...]
Investigating the water movements around a shallow shipwreck in Big Tub Harbour of Lake Huron: implications for managing underwater shipwrecks.
Published: 2019-06-27
Subjects: Earth Sciences, Environmental Sciences, Natural Resources Management and Policy, Physical Sciences and Mathematics
The Sweepstakes in Fathom Five National Marine Park is one of Ontarios more iconic shipwrecks. Continued exposure to water currents has directly and indirectly affected the integrity of the wreck and resulted in management interventions including efforts to stabilize the wreck and control vessel activity. An extensive series of field measurements were made during the peak tourist season in the [...]
Information-theoretic Portfolio Decision Model for Optimal Flood Management
Published: 2019-06-27
Subjects: Civil and Environmental Engineering, Civil Engineering, Computational Engineering, Earth Sciences, Engineering, Environmental Engineering, Environmental Health and Protection, Environmental Sciences, Geomorphology, Hydraulic Engineering, Hydrology, Life Sciences, Natural Resources and Conservation, Natural Resources Management and Policy, Operations Research, Systems Engineering and Industrial Engineering, Other Civil and Environmental Engineering, Other Engineering, Other Environmental Sciences, Other Physical Sciences and Mathematics, Physical Sciences and Mathematics, Probability, Risk Analysis, Statistics and Probability, Sustainability, Systems Engineering, Water Resource Management
The increasing impact of flooding urges more effective flood management strategies to guarantee sustainable ecosystem development. Recent catastrophes underline the importance of avoiding local flood management, but characterizing large scale basin wide approaches for systemic flood risk management. Here we introduce an information-theoretic Portfolio Decision Model (iPDM) for the optimization of [...]
The influence of a slope break on turbidite deposits: an experimental investigation
Published: 2019-06-24
Subjects: Earth Sciences, Physical Sciences and Mathematics, Sedimentology
Bypassing turbidity currents can travel downslope without depositing any of their suspended sediment load. Along the way, they may encounter a slope break (i.e. an abrupt decrease in slope angle) that initiates sediment deposition. Depending on the initiation point of deposition (the upslope pinch-out), these turbidite deposits in slope-break systems can form potential reservoirs for [...]
Pervasive foreshock activity across southern California
Published: 2019-06-22
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Foreshocks have been documented as preceding less than half of all mainshock earthquakes. These observations are difficult to reconcile with laboratory earthquake experiments and theoretical models of earthquake nucleation, which both suggest that foreshock activity should be nearly ubiquitous. Here we use a state-of-the-art, high-resolution earthquake catalog to study foreshock sequences of [...]
Multiple episodes of sand injection leading to accumulation and leakage of hydrocarbons along the San Andreas/San Gregorio fault system, California.
Published: 2019-06-22
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology, Tectonics and Structure
The presence of sand injections has proven to enhance the likelihood of hydrocarbon traps within siliciclastic successions. Through the development of large interconnected networks of sills and dykes, sand injection complexes provide a volume of porous and permeable rocks within the low permeability host units. Overall, the formation of sand injection complexes requires extensive fracturing and [...]
Are magnetic stripes on the Cuvier Abyssal Plain (offshore NW Australia) diagnostic of oceanic crust?
Published: 2019-06-22
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Other Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
Magnetic stripes have long been used to define the presence and age of oceanic crust. However, continental crust heavily intruded by magma can record magnetic reversals akin to those observed in oceanic crust. We re-evaluate the nature of the Cuvier Abyssal Plain (CAP), offshore NW Australia, which hosts magnetic stripes and has previously been defined as oceanic crust. We use magnetic, 2D [...]