Preprints
Filtering by Subject: Physical Sciences and Mathematics
Are Detected Trends in Flood Magnitude and Shifts in the Timing of Floods of A Major River Basin in India, Linked To Anthropogenic Stressors?
Published: 2019-04-10
Subjects: Applied Statistics, Civil and Environmental Engineering, Earth Sciences, Engineering, Hydraulic Engineering, Hydrology, Mathematics, Physical Sciences and Mathematics, Statistics and Probability
Analyzing of trends in flood magnitude and the timing of the dates of flood occurrences of large river basins across the globe are essential for understanding changes in water availability (high or low flows) and assessing the fidelity of global hydrological models. Our research is motivated by the recent six major consecutive floods in Mahanadi (years: 2001, 2003, 2006, 2008, 2011 and 2013) [...]
The stratigraphic evolution of onlap in siliciclastic deep-water systems: Autogenic modulation of allogenic signals
Published: 2019-04-09
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
Seafloor topography affects the sediment gravity flows that interact with it. Understanding this interaction is critical for accurate predictions of sediment distribution, paleogeography, and structural reconstructions of deep-water basins. The effects of seafloor topography can be seen from the bed scale, through facies transitions toward intra-basinal slopes, to the basin scale, where onlap [...]
Characterising strong force networks produced during granular shear using percolation methods: Revealing the bridge between local grain scale processes and macroscopic sliding
Published: 2019-04-08
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Other Earth Sciences, Physical Sciences and Mathematics, Physics, Tectonics and Structure
Faults, landslides and subglacial till often contain accumulations of granular debris. Their macroscopic motion is at least to some extent determined by the processes operating in this sheared granular material. A valid question in these environments is how the local behaviour at the individual granular contacts actually sums up to influence macroscopic sliding. Laboratory experiments and [...]
What has Global Sensitivity Analysis ever done for us? A systematic review to support scientific advancement and to inform policy-making in earth system modelling
Published: 2019-04-08
Subjects: Civil and Environmental Engineering, Computer Sciences, Earth Sciences, Engineering, Environmental Sciences, Life Sciences, Mathematics, Medicine and Health Sciences, Physical Sciences and Mathematics, Risk Analysis, Statistics and Probability
Computer models are essential tools in the earth system sciences. They underpin our search for understanding of earth system functioning and support decision- and policy-making across spatial and temporal scales. To understand the implications of uncertainty and environmental variability on the identification of such earth system models and their predictions, we can rely on increasingly powerful [...]
Illuminating water cycle modifications and Earth System resilience in the Anthropocene
Published: 2019-04-06
Subjects: Earth Sciences, Environmental Sciences, Hydrology, Physical Sciences and Mathematics
Fresh water – the bloodstream of the biosphere – is at the centre of the planetary drama of the Anthropocene. Water fluxes and stores regulate the Earth’s climate and are essential for thriving aquatic and terrestrial ecosystems, as well as water, food and energy security. But the water cycle is also being modified by humans at an unprecedented scale and rate. A holistic understanding of [...]
Fast non-linear gravity inversion in spherical coordinates with application to the South American Moho
Published: 2019-04-06
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Estimating the relief of the Moho from gravity data is a computationally intensive non-linear inverse problem. What is more, the modeling must take the Earths curvature into account when the study area is of regional scale or greater. We present a regularized non-linear gravity inversion method that has a low computational footprint and employs a spherical Earth approximation. To achieve this, we [...]
Comment on “Earthquake-induced prompt gravity signals identified in dense array data in Japan” by Kimura et al.
Published: 2019-04-05
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
A recent work by Kimura et al. (2019) (hereafter referred to as K19) claims to provide the first observational constraints on the prompt elastogravity signals (PEGS) induced by an earthquake. To make their claim, the authors argue that the observations shown in Vallée et al. (2017) (hereafter referred to as V17) are spurious and their modeling inaccurate. Here we show that K19’s claim is invalid [...]
Scaled Random Number Simulation of High Correlation Coefficients for Gasoline Range Compound Concentrations
Published: 2019-04-05
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics
It has been common practice to plot gasoline range parameters as absolute concentrations within crude oils of either single compounds, sums of compound pairs, or the square root of the products of concentrations of compounds. If a sample of crude such as a condensate has a relatively high concentration of volatile components, then the concentration of all of the gasoline range components tends to [...]
Matlab/R workflows to assess critical choices in Global Sensitivity Analysis using the SAFE toolbox
Published: 2019-04-05
Subjects: Applied Mathematics, Civil and Environmental Engineering, Computer Sciences, Earth Sciences, Engineering, Environmental Sciences, Physical Sciences and Mathematics, Risk Analysis, Statistics and Probability
Global Sensitivity Analysis (GSA) is a set of statistical techniques to investigate the effects of the uncertainty in the input factors of a mathematical model on the model’s outputs. The value of GSA for the construction, evaluation, and improvement of earth system models is reviewed in a companion paper by Wagener and Pianosi [n.d.]. The present paper focuses on the implementation of GSA and [...]
The vulnerability of tidal flats and multi-channel estuaries to dredging and disposal
Published: 2019-04-05
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Geomorphology, Other Civil and Environmental Engineering, Physical Sciences and Mathematics
Shipping fairways in estuaries are continuously dredged to maintain access for large vessels to major ports. However, several estuaries worldwide show adverse side effects to dredging activities, including a shift from multi-channel systems to single-channel systems and the loss of ecologically valuable intertidal flats. We used a time series of bathymetry of the Western Scheldt estuary (the [...]
Earthquake cycle modeling of the Cascadia subduction zone
Published: 2019-04-05
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The Cascadia subduction zone hosts great $\mathrm{M}_\mathrm{W} > 8.5$ earthquakes, but studying these events is hindered by our short observational record. Earthquake cycle simulation provides an alternative window into the behavior of the subduction zone. Here, we present simulations over 3,800 years, 14 ruptures and hundreds of slow slip events on a high-fidelity geometric representation of [...]
Dispersion, accumulation and the ultimate fate of microplastics in deep-marine environments: A review and future directions
Published: 2019-04-03
Subjects: Earth Sciences, Environmental Health and Protection, Environmental Indicators and Impact Assessment, Environmental Monitoring, Environmental Sciences, Natural Resources and Conservation, Physical Sciences and Mathematics, Sustainability
An estimated 8.3 billion tonnes of non-biodegradable plastic has been produced over the last 65 years. Much of this is not recycled and is disposed into the sedimentary system, has a long environmental residence time and accumulates in sedimentary systems worldwide, posing a threat to important ecosystems and potentially human health. We synthesise existing knowledge of seafloor microplastic [...]
Mapping geospatial processes affecting the environmental fate of agricultural pesticides in Africa
Published: 2019-04-02
Subjects: Environmental Health and Protection, Environmental Sciences, Physical Sciences and Mathematics
The application of agricultural pesticides in Africa has high negative effects on human health and the environment. To analyse the effect, spatial data characterizing the environmental fate of agricultural pesticides are needed. However, poor availability and quality of data that quantify pesticide application and pesticide fate limit direct analysis of the effect. This study selected key [...]
Determining cooling rates from mica 40Ar/39Ar thermochronology data: effect of cooling path shape
Published: 2019-04-02
Subjects: Earth Sciences, Geochemistry, Geology, Other Earth Sciences, Physical Sciences and Mathematics
Tectonic models are commonly underpinned by metamorphic cooling rates derived from diffusive-loss thermochronology data. Such cooling ages are usually linked to temperature via Dodson’s 1973 closure temperature (TC) formulation, which specifies a 1/time-shaped cooling path. Geologists, however, commonly discuss cooling rates as a linear temperature/time shape. We present the results of a series [...]
Ridge Subduction and Afterslip Control Aftershock Distribution of the 2016 Mw 7.8 Ecuador Earthquake
Published: 2019-04-02
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
We characterise the aftershock sequence following the 2016 Mw=7.8 Pedernales earthquake. More than 10,000 events were detected and located, with magnitudes up to 6.9. Most of the aftershock seismicity results from interplate thrust faulting, but we also observe a few normal and strike-slip mechanisms. Seismicity extends for more than 300 km along strike, and is constrained between the trench and [...]