Preprints
There are 6976 Preprints listed.
Local and remote influences on the heat content of Southern Ocean mode water formation regions.
Published: 2019-12-04
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The Southern Ocean (SO) is a crucial region for the global ocean uptake of heat and carbon. There are large uncertainties in the observations of fluxes of heat and carbon between the atmosphere and the ocean mixed layer, which leads to large uncertainties in the amount entering into the global overturning circulation. In order to better understand where and when fluxes of heat and momentum have [...]
Accelerating numerical wave-propagation using wavefield adapted meshes, Part I: Forward and adjoint modelling
Published: 2019-12-04
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
An order of magnitude speed-up in finite-element modelling of wave propagation can be achieved by adapting the mesh to the anticipated space-dependent complexity and smoothness of the waves. This can be achieved by designing the mesh not only to respect the local wavelengths, but also the propagation direction of the waves depending on the source location, hence by anisotropic adaptive mesh [...]
Urban Near-surface Seismic Monitoring using Distributed Acoustic Sensing
Published: 2019-11-26
Subjects: Civil and Environmental Engineering, Civil Engineering, Earth Sciences, Engineering, Geophysics and Seismology, Physical Sciences and Mathematics
Urban subsurface monitoring requires high temporal-spatial resolution, low maintenance cost, and minimal intrusion to nearby life. Distributed acoustic sensing (DAS), in contrast to conventional station-based sensing technology, has the potential to provide a passive seismic solution to urban monitoring requirements. Based on data recorded by the Stanford Fiber Optic Seismic Observatory, we [...]
Dreibrodt et al.- Holocene erosion history in central Ukraine
Published: 2019-12-04
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
The younger Quaternary erosion history was reconstructed in a catchment close to the Chalcolithic giant settlement Maidanetske, central Ukraine based on dated sediment sequences. Four trenches and a long percussion drill-core were analyzed in a valley grading from a Loess covered plateau towards the Talianky River. The sediments were dated via a combination of radiocarbon dating, optical [...]
Ferruginous oceans during OAE1a and collapse of the marine sulfate pool
Published: 2019-12-05
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics
Seawater sulfate is one of the largest oxidant pools at Earth’s surface today and its concentration in the oceans is generally assumed to have varied between 5 and 28 mM since the early Phanerozoic Eon. Intermittent and potentially global Oceanic Anoxic Events (OAEs) are accompanied by changes in seawater sulfate concentrations and signal perturbations in the Earth system associated with major [...]
The economic implications of using a truly preindustrial climate baseline
Published: 2019-12-04
Subjects: Climate, Geography, Human Geography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Social and Behavioral Sciences
The pervasive impacts of climate change can result in scientific decisions having unforeseen societal implications. To demonstrate this, we explore the global and regional economic implications of adopting an earlier preindustrial baseline of 1400-1800 for climate policy targets instead of the commonly used early industrial period of 1850-1900 for which we have observational data. Because of [...]
Effects of off-fault inelasticity on near-fault directivity pulses
Published: 2019-11-26
Subjects: Civil and Environmental Engineering, Engineering, Geotechnical Engineering
Near-fault motion is often dominated by long-period, pulse-like particle velocities with fault-normal polarization that, when enhanced by directivity, may strongly excite mid- to high-rise structures. We assess the extent to which plastic yielding may affect amplitude, frequency content, and distance scaling of near-fault directivity pulses. Dynamic simulations of 3D strike-slip ruptures reveal [...]
Gulf Stream and Kuroshio Current are synchronized
Published: 2019-11-05
Subjects: Atmospheric Sciences, Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Observational records show that sea surface temperatures along the Gulf Stream and Kuroshio tend to synchronize at decadal time scales. This synchronization, which we refer to as the Boundary Current Synchronization (BCS), is reproduced in global climate models with high spatial resolution. Both in observations and model simulations, BCS is associated with meridional migrations of the atmospheric [...]
A 2,000-year Bayesian NAO reconstruction from the Iberian Peninsula
Published: 2019-11-26
Subjects: Applied Statistics, Climate, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Other Earth Sciences, Physical Sciences and Mathematics, Statistics and Probability
The North Atlantic Oscillation (NAO) is the major atmospheric mode that controls winter European climate variability because its strength and phase determine regional temperature, precipitation and storm tracks. The NAO spatial structure and associated climatic impacts over Europe are not stationary making it crucial to understanding its past evolution in order to improve the predictability of [...]
Revised timing of Cenozoic Atlantic incursions and changing hinterland sediment sources during southern Patagonian orogenesis
Published: 2019-11-21
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Stratigraphy
New detrital zircon U-Pb geochronology data from the Cenozoic Magallanes-Austral Basin in Argentina and Chile ~51°S establish a revised chronostratigraphy of Paleocene – Miocene foreland synorogenic strata and document the rise and subsequent isolation of hinterland sources in the Patagonian Andes from the continental margin. The upsection loss of zircons derived from the hinterland Paleozoic and [...]
Effects of groundwater pumping on ground surface temperature: A regional modeling study in the North China Plain
Published: 2019-11-22
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Over-exploitation of groundwater (GW) in the North China Plain (NCP) since the 1960s has many environmental consequences. However, understanding of the dominant mechanisms remains limited, particularly at the regional scale. In this study, the coupled ParFlow.CLM model representing subsurface and land-surface processes and their interactions was applied in the NCP at high spatio-temporal [...]
Plants as sensors: vegetation response to rainfall predicts subsurface water storage capacity in Mediterranean climates
Published: 2019-11-22
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Methods are lacking to characterize critical zone (CZ) structure at spatial scales relevant to earth system and dynamic global vegetation models. This knowledge gap results in poor quantification of CZ plant-available water storage capacity, hindering realistic prediction of the response of plants and streamflow to anticipated changes in the hydrological cycle. Here, we exploit the phase offset [...]
Fault rupture during the December 26, 2018, Mw 4.9 Fleri earthquake (Mt. Etna): surface faulting in a volcano-tectonic environment
Published: 2020-02-04
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure, Volcanology
On December 26, 2018, the largest instrumental earthquake ever recorded in Mt. Etna (Sicily, southern Italy) shook the eastern flank of the volcano, with epicenter near the Fleri village along the right-lateral Fiandaca Fault (focal depth less than 1 km, Mw 4.9). The mainshock was accompanied by widespread surface faulting. We surveyed and mapped the coseismic ground ruptures and collected [...]
Centroid moment tensor inversions of offshore earthquakes using a three-dimensional velocity structure model: Slip distributions on the plate boundary along the Nankai Trough
Published: 2019-11-20
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Planetary Sciences
Due to complex three-dimensional (3D) heterogeneous structures, conventional one-dimensional (1D) analysis techniques using onshore seismograms can yield incorrect estimation of earthquake source parameters, especially dip angles and centroid depths of offshore earthquakes. Combining long-term onshore seismic observations and numerical simulations of seismic wave propagation in a 3D model, we [...]
Simulating Electropulse Fracture of Granitic Rock
Published: 2019-11-22
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Geology, Geotechnical Engineering, Mining Engineering, Physical Sciences and Mathematics
Electropulse treatments employ a series of high-voltage discharges to break rock into small fragments. As these methods are particularly suited to fracturing hard brittle rocks, electropulse treatments can serve to enhance or substitute for more traditional mechanical approaches to drilling and processing of these materials. Nevertheless, while these treatments have the potential to improve [...]