Preprints
Filtering by Subject: Earth Sciences
EC-Earth Global Climate Simulations: Ireland’s Contributions to CMIP6
Published: 2020-05-08
Subjects: Earth Sciences, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The global climate simulations described in this report constitute Ireland’s contribution to the Coupled Model Intercomparison Project (CMIP) (phase 6) (CMIP6) and will be included for assessment in the United Nations Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report (AR6). Since 1995, CMIP has co-ordinated climate model experiments involving multiple international [...]
A Reduced Order Approach for Probabilistic Inversions of 3D Magnetotelluric Data I: General Formulation
Published: 2020-05-07
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Simulation-based probabilistic inversions of 3D magnetotelluric (MT) data are arguably the best option to deal with the non-linearity and non-uniqueness of the MT problem. However, the computational cost associated with the modeling of 3D MT data has so far precluded the community from adopting and/or pursuing full probabilistic inversions of large MT datasets. In this contribution, we present a [...]
Estimating Submicron Aerosol Mixing State at the Global Scale with Machine Learning and Earth System Modeling
Published: 2020-05-07
Subjects: Atmospheric Sciences, Civil and Environmental Engineering, Computational Engineering, Computer Sciences, Earth Sciences, Engineering, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
This study integrates machine learning and particle-resolved aerosol simulations to develop emulators that predict sub-micron aerosol mixing state indices from the Earth System Model (ESM) simulations. The emulators predict aerosol mixing state using only ESM bulk aerosol species concentrations, which do not by themselves carry mixing state information. Here we used PartMC as the [...]
A radial hydraulic fracture with pressure-dependent leak-off
Published: 2020-05-07
Subjects: Earth Sciences, Environmental Sciences, Hydrology, Oil, Gas, and Energy, Physical Sciences and Mathematics, Volcanology
This paper investigates the problem of a radial (or penny-shaped) hydraulic fracture propagating in a permeable reservoir. In particular, we consider the fluid exchange between the crack and ambient porous media as a pressure-dependent process. In most of the existing models, the fluid exchange process is represented as one-dimensional pressure-independent leak-off described by Carters law. We [...]
Constraining crustal silica on ancient Earth
Published: 2020-05-07
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics
Accurately quantifying the composition of continental crust on Hadean and Archean Earth is critical to our understanding of the physiography, tectonics, and climate of our planet at the dawn of life. One longstanding paradigm involves the growth of a relatively mafic planetary crust over the first 1-2 billion years of Earth history, implying a lack of modern plate tectonics, a paucity of [...]
Unrealistic phytoplankton bloom trends in global lakes derived from Landsat measurements
Published: 2020-05-07
Subjects: Earth Sciences, Environmental Monitoring, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Water Resource Management
Given its advantages for synoptic and large-scale observations, satellite remote sensing has been widely used to effectively monitor the water quality of inland and coastal environments. Using satellite-derived reflectance data from the Landsat 5 Thematic Mapper (L5TM) as a proxy for algal bloom intensity, Ho et al. 1 showed an increase in peak summertime bloom intensity in 68% of the 71 large [...]
Do olivine crystallization temperatures faithfully record mantle temperature variability?
Published: 2020-05-07
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics
Crystallization temperatures of primitive olivine crystals have been widely used as both a proxy for, or an intermediate step in calculating, mantle temperatures. The olivine-spinel aluminum-exchange thermometer has been applied to samples from mid-ocean ridges and large igneous provinces, yielding considerable variability in olivine crystallization temperatures. We supplement the existing data [...]
Projections of global delta land loss from sea-level rise in the 21st century
Published: 2020-05-07
Subjects: Earth Sciences, Geomorphology, Hydrology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Sedimentology
River deltas will likely experience significant land loss because of relative sea-level rise (RSLR), but predictions have not been tested against observations. Here, we use global data of RSLR and river sediment supply to build a model of delta response to RSLR for 6,402 deltas, representing 86% of global delta land. We validate this model against delta land area change observations from [...]
Early earthquake detection capabilities of different types of future-generation gravity gradiometers
Published: 2020-05-07
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Since gravity propagates at the speed of light, gravity perturbations induced by earthquake deformation have the potential to enable faster alerts than the current earthquake early warning systems based on seismic waves. Additionally, for large earthquakes (Mw > 8), gravity signals may allow for a more reliable magnitude estimation than seismic-based methods. Prompt elastogravity signals [...]
Rock glaciers represent hidden water stores in the Himalaya
Published: 2020-05-07
Subjects: Earth Sciences, Geomorphology, Glaciology, Hydrology, Physical Sciences and Mathematics
In High Mountain Asia (HMA), ongoing glacier retreat affects human and ecological systems through reduced water availability. Rock glaciers are climatically more resilient than glaciers and likely contain potentially valuable water volume equivalents (WVEQ). In HMA knowledge of rock glaciers is extremely sparse and here we present the first systematic assessment of rock glaciers for the Himalaya, [...]
Permeability computation of high resolution µCTscan with an unfitted boundary method to improve accuracy
Published: 2020-05-07
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Geophysics and Seismology, Hydraulic Engineering, Hydrology, Physical Sciences and Mathematics
Flow simulations on porous media, reconstructed from Micro-Computerised Tomography (μCT)-scans, is becoming a common tool to compute the permeability of rocks. In order for the value of this homogenised hydraulic property to be representative of the rock at a continuum scale, the sample considered needs to be at least as large as the Representative Elementary Volume. More- over, the numerical [...]
Connecting the Deep Earth and the Atmosphere
Published: 2020-05-01
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
Most hotspots, kimberlites, and large igneous provinces (LIPs) are sourced by plumes that rise from the margins of two large low shear-wave velocity provinces in the lowermost mantle. These thermochemical provinces have likely been quasi-stable for hundreds of millions, perhaps billions of years, and plume heads rise through the mantle in about 30 Myr or less. LIPs provide a direct link between [...]
Constraining global changes in temperature and precipitation from observable changes in surface radiative heating
Published: 2020-04-30
Subjects: Climate, Earth Sciences, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Physics
Changes in the atmospheric composition alter the magnitude and partitioning between the downward propagating solar and atmospheric longwave radiative fluxes heating the Earths surface. These changes are computed by radiative transfer codes in Global Climate Models and measured with high precision at surface observation networks. Changes in radiative heating signify changes in the global surface [...]
Predicting outbreak-level tornado counts and casualties from environmental variables
Published: 2020-04-30
Subjects: Atmospheric Sciences, Earth Sciences, Life Sciences, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Environmental variables are used routinely in forecasting when and where an outbreak of tornadoes are likely to occur, but more work is needed to understand how characteristics of severe weather outbreaks vary with the larger scale environmental factors. Here the authors demonstrate a method to quantify `outbreak-level tornado and casualty counts with respect to variations in large-scale [...]
Structure and kinematics of an extensional growth fold, Hadahid Fault System, Suez Rift, Egypt
Published: 2020-04-30
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
Normal faulting drives extensional growth folding of the Earth’s upper crust during continental extension, yet we know little of how fold geometry relates to the structural segmentation of the underlying fault. We use field data from the Hadahid Fault System, Suez Rift, Egypt to investigate the geometry and kinematics of a large (30 km long, up to 2.5 km displacement), exceptionally well exposed [...]