Preprints
Filtering by Subject: Physical Sciences and Mathematics
The hazards of unconfined pyroclastic density currents: a new synthesis and classification according to their deposits, dynamics, and thermal and impact characteristics
Published: 2021-06-08
Subjects: Earth Sciences, Physical Sciences and Mathematics, Volcanology
Pyroclastic density currents (PDCs) that escape their confining channels are among the most dangerous of volcanic hazards. These unconfined PDCs are capable of inundating inhabited areas that may be unprepared for these hazards, resulting in significant loss of life and damage to infrastructure. Despite their ability to cause serious impacts, unconfined PDCs have previously only been described [...]
Use of multi-spectral visible and near-infrared satellite data for timely estimates of the Earth's surface reflectance in cloudy conditions: Part 2 - image restoration with HICO satellite data in overcast conditions
Published: 2021-06-08
Subjects: Physical Sciences and Mathematics
Satellite-based visible and near-infrared imaging of the Earth's surface is generally not performed in moderate to highly cloudy conditions; images that look visibly cloud covered to the human eye are typically discarded. Here, we expand upon previous work that employed machine learning (ML) to estimate underlying land surface reflectances at red, green, and blue (RGB) wavelengths in cloud [...]
On the statistical learning analysis of rain gauge data over the Natuna Islands
Published: 2021-06-08
Subjects: Applied Statistics, Atmospheric Sciences, Longitudinal Data Analysis and Time Series, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Statistics and Probability
This article presents state-of-the-art statistical learning methods for analyzing rain gauge data over the Natuna Islands. By using shape preserving piecewise cubic interpolation, we managed to interpolate 671 null values from the daily precipitation data. Dominant periodicity analysis of daily precipitation signals using Lomb-Scargle Power Spectral Density shows annual, intraseasonal, and [...]
Use of multi-spectral visible and near-infrared satellite data for timely estimates of the Earth's surface reflectance in cloudy and aerosol loaded conditions: Part 1 - application to RGB image restoration over land with GOME-2
Published: 2021-06-07
Subjects: Physical Sciences and Mathematics
Space-based quantitative passive optical remote sensing of the Earth's surface typically involves the detection and elimination of cloud-contaminated pixels as an initial processing step. We explore a fundamentally different approach; we use machine learning with cloud contaminated satellite multi-spectral data to estimate underlying terrestrial surface reflectances at red, green, and blue (RGB) [...]
Equilibrated gas and carbonate standard-derived paired clumped isotope (Δ47 and Δ48) values on the absolute reference frame
Published: 2021-06-05
Subjects: Physical Sciences and Mathematics
Rationale: Carbonate clumped isotope geochemistry has primarily focused on mass spectrometric determination of m/z 47 CO2 for geothermometry, but theoretical calculations and recent experiments indicate paired analysis of the m/z 47 (13C18O16O) and m/z 48 (12C18O18O) isotopologues (referred to as Δ47 and Δ48) can be used to study non-equilibrium isotope fractionations and refine temperature [...]
Influence of fault zone maturity on fully dynamic earthquake cycles
Published: 2021-06-04
Subjects: Physical Sciences and Mathematics
We study the mechanical response of two-dimensional vertical strike-slip fault to coseismic damage evolution and interseismic healing of fault damage zones by simulating fully dynamic earthquake cycles. Our models show that fault damage zone structure evolution during the seismic cycle can have pronounced effects on the mechanical behavior of locked and creeping fault segments. Immature fault [...]
Multi-task deep learning of daily streamflow and water temperature
Published: 2021-06-04
Subjects: Hydrology, Physical Sciences and Mathematics
Deep learning models can accurately predict many hydrologic variables including streamflow and water temperature; however, these models have typically predicted hydrologic variables independently. This study explored the benefits of modeling two interdependent variables, daily average streamflow and daily average stream water temperature, together using multi-task deep learning. A multi-task [...]
The effect of temperature-dependent material properties on simple thermal models of subduction zones
Published: 2021-06-03
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
To a large extent, the thermal structure of a subduction zone determines where seismicity occurs through the transition from brittle to ductile deformation and the depth of dehydration reactions. Thermal models of subduction zones can help understand this seismicity by accurate modelling of the thermal structure of the subduction zone. Here, we assess a common simplification in thermal models of [...]
The erosive power of the Malvinas Current: Influence of bottom currents on morpho-sedimentary features along the northern Argentine margin (SW Atlantic Ocean)
Published: 2021-06-02
Subjects: Physical Sciences and Mathematics
Sediment deposits formed mainly under the influence of bottom currents (contourites) are widely used as high-resolution archives for reconstructing past ocean conditions. However, the driving processes of Contourite Depositional Systems (CDS) are not entirely understood. The aim of this study is to establish a clearer link between contourite features and the oceanographic processes that form [...]
An occurrence of radially-symmetric sedimentary structures in the basal Ediacaran cap dolostone (Keilberg Member) of the Otavi Group
Published: 2021-06-02
Subjects: Life Sciences, Physical Sciences and Mathematics
Snowball Earth cap carbonate sequences provide an archive of what are likely the most dramatic climate transitions in all of Earth history. One approach to gain insight into these events is the detailed observation of sedimentary structures within these post-glacial units. Here, we report on newly discovered radially-symmetric sedimentary structures within the Keilberg Member post-Marinoan ‘cap [...]
Canadian emissions and unconventional oil production exceed the 2°C global warming scenario
Published: 2021-06-01
Subjects: Environmental Sciences, Natural Resources Management and Policy, Physical Sciences and Mathematics
Canada could highly impact the climate, as it possesses the world’s third largest resources of unconventional oil. This paper evaluates in three ways whether Canada is respecting a scenario of fossil fuel production and greenhouse gas (GHG) emissions limiting warming to 2.0 °C by 2100. Firstly, McGlade and Ekins (2015) proposed a model providing production budgets for each fossil fuel producing [...]
Hydrology Research Articles are Becoming More Topically Diverse
Published: 2021-06-01
Subjects: Physical Sciences and Mathematics
We used Natural Language Processing (NLP) to assess topic diversity in all research articles (∼75,000) from eighteen water science and hydrology journals published between 1991 and 2019. We found that individual water science and hydrology research articles are becoming increasingly interdisciplinary in the sense that, on average, the number of equally-common topics represented in individual [...]
Iron oxide copper-gold (IOCG) deposits – A review (part 1): Settings, mineralogy, ore geochemistry and classification
Published: 2021-06-01
Subjects: Physical Sciences and Mathematics
Characteristics of ten of the world’s metallogenic provinces hosting iron oxide Cu-Au (IOCG) deposits have been critically assessed, including their geological and tectonothermal evolution, alteration-mineralisation parageneses, and ore geochemistry. A new classification framework is proposed in which IOCG deposits form the major part of a family of deposits within Cu-Au-Fe (CGI) mineral systems. [...]
European carbon storage resource requirements of climate change mitigation targets
Published: 2021-05-28
Subjects: Engineering, Physical Sciences and Mathematics
As a part of climate change mitigation plans in Europe, CO2 storage scenarios have been reported for the United Kingdom and the European Union with injection rates reaching 75 – 330 MtCO2 yr-1 by 2050. However, these plans are not constrained by geological properties or growth rates with precedent in the hydrocarbon industry. We use logistic models to identify growth trajectories and the [...]
Novel sensor array helps to understand submarine cable faults off West Africa
Published: 2021-05-28
Subjects: Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics
Seabed telecommunication cables can be damaged or broken by powerful seafloor flows of sediment (called turbidity currents), which may runout for hundreds of kilometres into the deep ocean. These flows have the potential to affect multiple cables near-simultaneously over very large areas, so it is more challenging to reroute traffic or repair the cables. However, cable-breaking turbidity currents [...]