Preprints
There are 6976 Preprints listed.
Improved Accuracy of Watershed-Scale General Circulation Model Runoff Using Deep Neural Networks
Published: 2020-01-02
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Projecting impacts of climate change on water resources is a vital research task, and general circulation models (GCMs) are important tools for this work. However, the spatial resolution of downscaled GCMs makes them difficult to apply to non-grid conforming scales relevant to water resources management: individual watersheds. Machine learning techniques like deep neural networks (DNNs) may [...]
The first climate tipping point – Already in the past?
Published: 2020-01-03
Subjects: Life Sciences, Other Life Sciences
Humanity may have passed its first climate tipping point and face self-sustained melting of the permafrost for hundreds of years even if all man-made GHG emissions are stopped.
Landscape variables in the Indian (Peninsular) catchments: insights into hydro-geomorphic evolution
Published: 2020-01-02
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
The river systems in peninsular India are remained unexplored in terms of hydro-geomorphic evolution, though a few works are carried out in order to understand the tectonic and structural evolution with paleoclimate. Morphometric analysis at catchment scale delivers insights into the dynamics, erosion capacity, probability of flood occurrence, lithological and structural control, and genetic [...]
Global mean surface temperature and climate sensitivity of the EECO, PETM and latest Paleocene
Published: 2020-01-02
Subjects: Earth Sciences, Physical Sciences and Mathematics
Accurate estimates of past global mean surface temperature (GMST) help to contextualise future climate change and are required to estimate the sensitivity of the climate system to CO2 forcing during the geological record. GMST estimates from the latest Paleocene and early Eocene (~57 to 48 million years ago) span a wide range (~9 to 23°C higher than pre-industrial) and prevent an accurate [...]
Using a consistency factor for detection and attribution of anthropogenic impacts on phenological phases in Germany
Published: 2020-01-01
Subjects: Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
An important consequence of climate change is the impact on the seasonal cycle of vegetation flora and fauna. Although it is generally understood that anthropogenic mechanisms play a major role in the warming trend of the climate and that the timing of such phases, especially spring timing events, depends largely on the temperature, the link has yet to be quantitatively shown for different kind [...]
Artificial and natural radionuclides in cryoconite as tracers of supraglacial dynamics
Published: 2020-01-02
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
Cryoconite, a sediment found on the surface of glaciers, is known for its ability to accumulate radionuclides. New data on cryoconite from the Morteratsch glacier (Switzerland) are presented with the aim to shed light on the mechanisms that control the distribution of radioactivity in cryoconite. Among the many radionuclides detected in our samples, we have identified 108mAg, an artificial [...]
Back-propagating super-shear rupture in the 2016 Mw7.1 Romanche transform fault earthquake
Published: 2019-12-25
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
How an earthquake rupture propagates strongly influences potentially destructive ground shaking. Complex ruptures often involve slip along multiple faults, masking information on the frictional behaviour of fault zones. Geometrically smooth ocean transform fault plate boundaries offer a favourable environment to study fault dynamics, because strain is accommodated along a single, wide fault zone [...]
Fault-zone damage promotes pulse-like rupture and back-propagating fronts via quasi-static effects
Published: 2019-12-25
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Damage zones are ubiquitous components of faults that may affect earthquake rupture. Simulations show that pulse-like rupture can be induced by the dynamic effect of waves reflected by sharp fault zone boundaries. Here we show that pulses can appear in a highly damaged fault zone even in the absence of reflected waves. We use quasi-static scaling arguments and quasi-dynamic earthquake cycle [...]
Single-blind test of airplane-based hyperspectral methane detection via controlled releases
Published: 2020-01-08
Subjects: Education, Engineering, Other Engineering
Methane leakage from point sources in the oil and gas industry is a major contributor to global greenhouse gas emissions. The majority of such emissions come from a small fraction of ``super-emitting" sources. We evaluate the emission detection and quantification capabilities of Kairos Aerospace’s airplane-based hyperspectral imaging methane emission detection system for methane fluxes of 18 to [...]
Wind-driven evolution of the North Pacific subpolar gyre over the last deglaciation
Published: 2019-11-26
Subjects: Climate, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
North Pacific atmospheric and oceanic circulations are key missing pieces in our understanding of the reorganisation of the global climate system since the Last Glacial Maximum (LGM). Here, using a basin-wide compilation of planktic foraminiferal oxygen isotopes, we show that the North Pacific subpolar gyre extended ~3° further south during the LGM, consistent with sea surface temperature and [...]
Paleotsunami record of the past 4300 years in the complex coastal lake system of Lake Cucao, Chiloé Island, south central Chile
Published: 2020-01-08
Subjects: Earth Sciences, Physical Sciences and Mathematics, Sedimentology
In CE 1960, Lake Cucao on Chiloé Island in south central Chile was inundated by the tsunami of the Great Chilean Earthquake (Mw 9.5). The area of what is now the lake basin has been submerged since the end of the rapid postglacial sea-level rise and has recorded tsunami inundations in its sediment record since then. This study reconstructs the tsunami history of Lake Cucao. Reflection-seismic [...]
Goal-Oriented Error Estimation and Mesh Adaptation for Shallow Water Modelling
Published: 2019-12-31
Subjects: Applied Mathematics, Computer Sciences, Engineering, Non-linear Dynamics, Numerical Analysis and Computation, Numerical Analysis and Scientific Computing, Partial Differential Equations, Physical Sciences and Mathematics
Numerical modelling frequently involves a diagnostic quantity of interest (QoI) - often of greater importance than the PDE solution - which we seek to accurately approximate. In the case of coastal ocean modelling the power output of a tidal turbine farm is one such example. Goal-oriented error estimation and mesh adaptation can be used to provide meshes which are well-suited to achieving this [...]
Seismic reflection data reveal the 3D structure of the newly discovered Exmouth Dyke Swarm, offshore NW Australia
Published: 2019-12-25
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
Dyke swarms are common on Earth and other planetary bodies, comprising arrays of dykes that can extend laterally for 10’s to 1000’s of kilometres. The vast extent of such dyke swarms, and their presumed rapid emplacement, means they can significantly influence a variety of planetary processes, including continental break-up, crustal extension, resource accumulation, and volcanism. Determining the [...]
Effects of aseismic ridge subduction on geochemistry of frontal arc magmas
Published: 2019-12-13
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics
Aseismic ridge subduction is considered to exert major controls on volcanic activity, formation of porphyry Cu-Au deposits and the generation of juvenile Earth’s crust. Yet, there are almost no studies that have addressed in a systematic way the effects of this process on the geochemistry of arc magmas. Here we explore the role of the subducted aseismic Carnegie ridge on modulating frontal arc [...]
Policy Bridge: Air Quality Impacts from Oil and Natural Gas Development in Colorado
Published: 2019-12-13
Subjects: Environmental Education, Environmental Health and Protection, Environmental Monitoring, Environmental Sciences, Oil, Gas, and Energy, Physical Sciences and Mathematics
The rise of hydraulic fracturing techniques has fostered rapid growth of oil and natural gas extraction in areas across the United States. In the Denver-Julesburg Basin (DJB), which mostly overlaps with Weld County in the Northern Colorado Front Range (NCFR) north of the City of Denver Metropolitan Area (DMA), the well drilling has increasingly approached, and in many instances moved into urban [...]