Preprints
There are 5516 Preprints listed.
Constraining crustal silica on ancient Earth
Published: 2020-05-06
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: 2020-05-06
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 [...]
Evaluating Controller Performance and Placement on System-level Urban Flooding Reduction and Water Quality Improvement
Published: 2020-05-06
Subjects: Civil and Environmental Engineering, Civil Engineering, Engineering, Environmental Engineering
Increases in urbanization and climate change are forcing urban drainage engineers to more effectively leverage stormwater storage facilities to minimize flooding and water quality impacts. This process becomes increasingly challenging due to the operations of storage coordination across the system-level watershed. This study presents a system-level real-time control simulation for assessing [...]
Do olivine crystallization temperatures faithfully record mantle temperature variability?
Published: 2020-05-06
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: 2020-05-06
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: 2020-05-06
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: 2020-05-06
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: 2020-05-06
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: 2020-04-30
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 [...]
A Data-driven Improved Fuzzy Logic Control Optimization-simulation Tool for Reducing Flooding Volume at Downstream Urban Drainage Systems
Published: 2020-04-30
Subjects: Civil and Environmental Engineering, Civil Engineering, Engineering, Environmental Engineering
The uncertainty of climate change and urbanization imposed additional stress for urban drainage systems (UDSs) by intensifying rainfall frequency and magnifying peak runoff rate. UDSs are among the stormwater infrastructures that can be controlled in real-time for mitigating downstream urban flooding. In this paper, a data-driven improved real-time control optimization-simulation tool called [...]
A Performance Comparison of Unsupervised Machine Learning Algorithms for Clustering Water Depth Datasets at Urban Drainage Systems
Published: 2020-04-30
Subjects: Civil and Environmental Engineering, Civil Engineering, Engineering, Environmental Engineering
As sensor measurements emerge in urban water systems, data-driven unsupervised machine learning algorithms have been drawn tremendous interest in infrastructure monitoring, flow prediction, and pollutant warning recently. However, most of them are applied in water distribution systems, and few studies consider using unsupervised clustering analysis to group the time-series hydraulic-hydrologic [...]
Predicting outbreak-level tornado counts and casualties from environmental variables
Published: 2020-04-29
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 [...]
Large-eddy simulation of traffic-related air pollution at a very high-resolution in a mega-city: Evaluation against mobile sensors and insights for influencing factors
Published: 2020-04-29
Subjects: Atmospheric Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Urban air pollution has tremendous spatial variability at scales ranged from kilometer to meters due to unevenly distributed emission sources, complex flow patterns, and photochemical reactions. However, high-resolution air quality information is not available through traditional approaches such as ground-based measurements and regional air quality models (with typical resolution >1 km). Here [...]
Coupling Mars ground and orbital views: generate viewsheds of Mastcam images from the Curiosity rover, using ArcGIS® and public datasets.
Published: 2020-04-29
Subjects: Other Planetary Sciences, Physical Sciences and Mathematics, Planetary Geology, Planetary Sciences
The Mastcam (Mast Camera) instrument onboard the NASA Curiosity rover provides an exclusive view of Mars: the color high-resolution Mastcam images allow users to study Gale crater’s geological terrains and landscapes along the rover path. This view from the ground complements the spatially broader view provided by spacecrafts from orbit. However, for a given Mastcam image, it can be challenging [...]