Preprints
There are 4725 Preprints listed.
An Active Learning Pipeline to Detect Hurricane Washover in Post-Storm Aerial Images
Published: 2020-12-02
Subjects: Environmental Monitoring, Geomorphology, Physical Sciences and Mathematics
We present an active learning pipeline to identify hurricane impacts on coastal landscapes. Previously unlabeled post-storm images are used in a three component workflow — first an online interface is used to crowd-source labels for imagery; second, a convolutional neural network is trained using the labeled images; third, model predictions are displayed on an interactive map. Both the labeler [...]
Stalagmite carbon isotopes suggest deglacial increase in soil respiration in Western Europe driven by temperature change
Published: 2020-12-02
Subjects: Biogeochemistry, Climate, Earth Sciences, Geochemistry, Physical Sciences and Mathematics, Speleology
The temperate region of Western Europe underwent dramatic climatic and environmental change during the last deglaciation. Much of what is known about the terrestrial ecosystem response to deglacial warming stems from pollen preserved in sediment sequences, providing information on vegetation composition. Other ecosystem processes, such as soil respiration, remain poorly constrained over past [...]
Coordination numbers in natural beach sand
Published: 2020-12-02
Subjects: Geophysics and Seismology, Geotechnical Engineering, Sedimentology
Coordination number controls elastic moduli, seismic velocity, and force transmission in sands and is thus a critical factor controlling the resistance of sands to deformation. Previous studies quantified relationships between coordination number, porosity, grain size, sphericity, and effective stress in pluviated or modeled sands. Here, we determine if these relationships hold in [...]
Listening for the Landing: Detecting Perseverance’s landing with InSight
Published: 2020-12-02
Subjects: Physical Sciences and Mathematics
The entry, descent, and landing (EDL) sequence of NASA's Mars 2020 Perseverance rover will act as a seismic source of known temporal and spatial localization. We evaluate whether the signals produced by this event will be detectable at the InSight lander (3452~km away), comparing expected signal amplitudes to noise levels at the instrument. Modeling is undertaken to predict the propagation of the [...]
Operationalising coastal resilience to flood and erosion hazard: A demonstration for England
Published: 2020-12-02
Subjects: Geomorphology, Nature and Society Relations, Physical and Environmental Geography, Sustainability
Resilience is widely seen as an important attribute of coastal systems and, as a concept, is increasingly prominent in policy documents. However, there are conflicting ideas on what constitutes resilience and its operationalisation as an overarching principle of coastal management remains limited. In this paper, we show how resilience to coastal flood and erosion hazard could be measured and [...]
Recording earthquakes for tomographic imaging of the mantle beneath the South Pacific by autonomous MERMAID floats
Published: 2020-12-02
Subjects: Geophysics and Seismology
We present the first 16 months of data returned from a mobile array of 16 freely floating diving instruments, named MERMAID for Mobile Earthquake Recording in Marine Areas by Independent Divers, launched in French Polynesia in late 2018. Our 16 are a subset of the 50 MERMAID deployed over a number of cruises in this vast and understudied oceanic province as part of the collaborative South Pacific [...]
Cascadia megathrust earthquake rupture model constrained by geodetic fault locking
Published: 2020-11-30
Subjects: Earth Sciences
Paleo-earthquakes along the Cascadia subduction zone inferred from offshore sediments and Japan coastal tsunami deposits approximated to M9+ and ruptured the entire margin. However, due to the lack of modern megathrust earthquake records and generally quiescence of subduction fault seismicity, the potential megathrust rupture scenario and influence of downdip limit of the seismogenic zone are [...]
Chemistry speedup in reactive transport simulations: purely data-driven and physics-based surrogates
Published: 2020-11-30
Subjects: Earth Sciences, Geochemistry
The computational costs associated with coupled reactive transport simulations are mostly due to the chemical subsystem: replacing it with a pre-trained statistical surrogate is a promising strategy to achieve decisive speedups at price of small accuracy losses and thus to extend the scale of problems which can be handled. We introduce a hierarchical coupling scheme in which ``full [...]
The shape of volcanic conduits inferred from bubble size distributions
Published: 2020-11-28
Subjects: Earth Sciences, Volcanology
The most intense known explosive volcanic eruptions on Earth are Plinian eruptions of silicic magma. Geospeedometers indicate that Plinian magma erupts from high pressure within the magma chamber at average speeds of 0.001-1 MPa/s. Concurrently dissolved magmatic volatiles, predominantly water, nucleate about one quadrillion bubbles per cubic meter of melt, preserved as vesicles within tephra. [...]
Carbonate clumped isotope analysis (Δ47) of 21 carbonate standards determined via gas source isotope ratio mass spectrometry on four instrumental configurations using carbonate-based standardization and multi-year datasets
Published: 2020-11-28
Subjects: Chemistry, Earth Sciences, Physical Sciences and Mathematics
Rationale: Clumped isotope geochemistry examines the pairing or clumping of rare, heavy isotopes in molecules and provides information about the thermodynamic and kinetic controls on their formation. Since clumped isotope measurements of carbonate minerals were first published 15 years ago, interlaboratory offsets in calibrations have been observed, and laboratory and community practices for [...]
High-resolution downscaled CMIP5 projections dataset of essential surface climate variables over Europe coherent with ERA5-Land reanalyses for climate change impact assessments
Published: 2020-11-27
Subjects: Engineering, Life Sciences, Physical Sciences and Mathematics
A high-resolution climate projections dataset is obtained by statistically downscaling climate projections from the CMIP5 experiment using the ERA5-Land reanalyses from the Copernicus Climate Change service. The dataset is over Europe, has a spatial resolution of 0.10° x 0.10°, comprises 21 climate models and includes 5 surface daily variables: air temperature (mean, minimum, and maximum), [...]
High-resolution downscaled CMIP5 projections dataset of essential surface climate variables over the globe coherent with ERA5 reanalyses for climate change impact assessments
Published: 2020-11-27
Subjects: Engineering, Life Sciences, Physical Sciences and Mathematics
A high-resolution climate projections dataset is obtained by statistically downscaling climate projections from the CMIP5 experiment using the ERA5 reanalyses from the Copernicus Climate Change service. The dataset is global has a spatial resolution of 0.25°x 0.25°, comprises 21 climate models and includes 5 surface daily variables: air temperature (mean, minimum, and maximum), precipitation, and [...]
Reconstructing the morphologies and hydrodynamics of ancient rivers from source to sink: Cretaceous Western Interior Basin, Utah, USA
Published: 2020-11-25
Subjects: Earth Sciences, Geology, Geomorphology, Hydrology, Sedimentology, Stratigraphy
Quantitative reconstruction of palaeohydrology from fluvial stratigraphy provides sophisticated insights into the response, and relative impact, of tectonic and climatic drivers on ancient fluvial landscapes. Here, field measurements and a suite of quantitative approaches are used to develop a four-dimensional (space and time) reconstruction of palaeohydrology in Late Cretaceous palaeorivers of [...]
A benthic light index of water quality in the Great Barrier Reef, Australia
Published: 2020-11-25
Subjects: Life Sciences, Physical Sciences and Mathematics
Good water quality is essential to the health of marine ecosystems, yet current metrics used to track water quality in the Great Barrier Reef are not strongly tied to ecological outcomes. There is a need for a better water quality index (WQI). Benthic light, the amount of light reaching the seafloor, is critical for coral and seagrass health and is strongly affected by water quality. It therefore [...]
Enhanced hydrological cycle increases ocean heat uptake and moderates transient climate sensitivity
Published: 2020-11-25
Subjects: Climate, Oceanography, Oceanography and Atmospheric Sciences and Meteorology
The large-scale moistening of the atmosphere in response to increasing greenhouse gases amplifies the existing patterns of precipitation minus evaporation (P-E) which, in turn, amplifies the spatial contrast in sea surface salinity (SSS). Through a series of CO2 doubling experiments, we demonstrate that surface salinification driven by the amplified dry conditions (P-E < 0), primarily in the [...]