Preprints
There are 6976 Preprints listed.
On the modulation of kinetic energy transfer by internal gravity waves
Published: 2022-01-24
Subjects: Physical Sciences and Mathematics
Understanding how kinetic energy (KE) is exchanged across scales and eventually dissipated remains a key question in physical oceanography. Recent theoretical works suggests that both quasi-balanced submesoscale motions and internal gravity waves (IGWs) could play a role in fluxing KE towards dissipation. How these classes of motions actually provide a route to dissipation in the ocean is still [...]
Quaternary E-W extension uplifts Kythira Island and segments the Hellenic Arc
Published: 2022-01-25
Subjects: Geology, Geomorphology, Paleontology, Sedimentology, Stratigraphy, Tectonics and Structure
Several crustal and lithospheric mechanisms lead to deformation and vertical motion of the upper plate during subduction, but their relative contribution is often enigmatic. Multiple areas of the Hellenic Forearc have been uplifting since Plio-Quaternary times, yet spatiotemporal characteristics and sources of this uplift are poorly resolved. The remarkable geology and geomorphology of Kythira [...]
Numerical simulation of atmospheric Lamb waves generated by the 2022 Hunga-Tonga volcanic eruption
Published: 2022-02-09
Subjects: Oceanography and Atmospheric Sciences and Meteorology
On January 15th, 2022, around 4:30 UTC the eruption of the Hunga-Tonga volcano, in the South Pacific Ocean, generated a violent underwater explosion. In addition to tsunami waves that affected the Pacific coasts, the eruption created atmospheric pressure disturbances that spread out in the form of Lamb waves. The associated atmospheric pressure oscillations were detected in high-frequency in-situ [...]
Frontier metrics for a process-based understanding of deforestation dynamics
Published: 2022-01-24
Subjects: Agriculture
Agricultural expansion into tropical and subtropical forests often leads to major social-ecological trade-offs. Yet, despite ever-more detailed information on where deforestation occurs, how agriculture expands into forests remains unclear. Here, we developed and mapped a novel set of metrics that quantify agricultural frontier processes at unprecedented spatial and temporal detail. Specifically, [...]
Paired Δ47 and Δ48 analyses and model calculations constrain equilibrium, experimentally-manipulated kinetic isotope effects, and mixing effects in calcite
Published: 2022-01-25
Subjects: Physical Sciences and Mathematics
The high-precision analysis of the abundance of the dominant m/z 47 CO2 isotopologue derived from acid digestion of carbonate minerals (13C18O16O; denoted by Δ47) forms the basis for carbonate clumped isotope thermometry. Since the first measurements were published 16 years ago, considerable effort has gone into characterizing the relationship between Δ47 and carbonate precipitation temperature, [...]
Tectonics dominates over climatic and oceanographic factors in controlling the physiography of the Americas shelf-break at a continental scale
Published: 2022-01-25
Subjects: Earth Sciences, Physical Sciences and Mathematics
The continental shelf-break defines the boundary between shallow- and deep-ocean environments, and is modified by subaerial and submarine processes through geological time. The physiography of the shelf-break therefore records the cumulative influence of these processes, and dictates where, and how efficiently, particulates and pollutants are transported into the deep-ocean. Despite its [...]
3D Convective/Stratiform Echo Type Classification and Convectivity Retrieval from Radar Reflectivity
Published: 2022-01-26
Subjects: Oceanography and Atmospheric Sciences and Meteorology
The newly developed ECCO (Echo Classification from COnvectivity) algorithm identifies convective and stratiform types of radar echo in three dimensions. It is based on the calculation of reflectivity texture - a measure of the heterogeneity of the radar echoes on each horizontal plane in a 3D Cartesian volume. Reflectivity texture is translated into convectivity, which is a newly invented [...]
Deformation mechanisms and characteristics of the meta-BIFs from an early Proterozoic shear system of the Southern Granulite Terrane (SGT), India
Published: 2022-01-27
Subjects: Earth Sciences
We studied three samples of Banded Iron Formation (BIF) rocks from Southern Granulite Terrane (SGT) of India, which was metamorphosed at high-pressure granulite facies and exhumed from 40-50 km depth. We examined the microstructure, texture, and deformation mechanisms of the primary minerals (quartz, magnetite, and hematite). Microstructures, variations in size and shape of quartz grains suggest [...]
MODELLING EFFECTS OF FOREST FIRE AND POST-FIRE MANAGEMENT IN A CATCHMENT PRONE TO EROSION: Impacts on sediment yield
Published: 2022-01-27
Subjects: Engineering
The present paper contributes to bridging the gaps in modelling post-fire impact and mitigation measures on soil erosion. The specific aims were to predict the effects of forest fires and post-fire mitigation measures on runoff and specific sediment yield (SSY) in a river basin (Celone, S-E Italy). The Soil and Water Assessment Tool model, calibrated with field observations, was used to evaluate [...]
Multidimensional Governing Equations of Matrix Flow Component of Subsurface Stormflow as Function of Bedrock Surface Geometry
Published: 2022-01-27
Subjects: Civil and Environmental Engineering, Engineering, Physical Sciences and Mathematics
Powering Earth’s ancient dynamo with silicon precipitation
Published: 2022-01-27
Subjects: Earth Sciences, Geochemistry, Geophysics and Seismology
Earth's core has produced a global magnetic field for the last 4 Gyrs, presently sustained by inner core growth. Models of the core with high thermal conductivity suggest potentially insufficient power available for the geodynamo prior to inner core formation ~1 Ga. Precipitation of SiO2 from the liquid core might offer an alternative power source for the magnetic field before inner core [...]
University of Sheffield Department of Geography Policy on Equality, Diversity and Inclusion for field classes
Published: 2022-01-28
Subjects: Earth Sciences, Geography, Higher Education, Scholarship of Teaching and Learning
Field-based teaching forms an important part of BSc/BA degree courses in Human Geography, Physical Geography, Environmental Science and taught postgraduate courses. The aim of this policy is to ensure that all students and teaching staff are able, and feel safe, to participate fully in compulsory and optional field classes offered by the Department of Geography. This is shared with the intention [...]
Integrating Connectivity Into Hydrodynamic Models: An Automated Open-Source Method to Refine an Unstructured Mesh Using Remote Sensing
Published: 2022-01-27
Subjects: Earth Sciences, Environmental Engineering, Numerical Analysis and Scientific Computing
Hydrodynamic models are an essential tool for studying the movement of water and other materials across the Earth surface. However, the possible questions which models can address remain limited by practical constraints on model size and resolution, particularly in fluvial and coastal environments in which hydrodynamically-relevant landscape features are topologically complex and span a wide [...]
Two decades of changing anthropogenic mercury emissions in Australia: inventory development, trends, and atmospheric implications
Published: 2022-01-27
Subjects: Atmospheric Sciences, Biogeochemistry, Environmental Health and Protection
Mercury is a toxic environmental pollutant emitted into the atmosphere by both natural and anthropogenic sources. In Australia, previous estimates of anthropogenic mercury emissions differ by up to a factor of three, with existing inventories either outdated or inaccurate and several lacking Australia-specific input data. Here, we develop a twenty-year inventory of Australian anthropogenic [...]
Vertically Resolved Convective/Stratiform Echo Type Identification and Convectivity Retrieval for Vertically Pointing Radars
Published: 2022-01-27
Subjects: Atmospheric Sciences, Meteorology, Oceanography and Atmospheric Sciences and Meteorology
Using data from the airborne HIAPER Cloud Radar (HCR), a partitioning algorithm (ECCO-V) that provides vertically resolved convectivity and convective vs stratiform radar echo classification is developed for vertically pointing radars. The algorithm is based on the calculation of reflectivity and radial velocity texture fields that measure the horizontal homogeneity of cloud and precipitation [...]