Preprints
There are 4721 Preprints listed.
Soil Excavation pH level Modification
Published: 2021-12-06
Subjects: Engineering
Territories are becoming new areas for conservationist replanting and forestation. Excavators are capable of producing entrainment s for new reservations. There lacks knowledge of soil conditions and methods of measurement of fertility of the developments. This research improves knowledge on the subject of excavations. To decide on territories which can be a best fit for excavations.
Timing of oil expulsion from source rocks and a revitalization of the pre-1970 model
Published: 2021-12-06
Subjects: Earth Sciences, Physical Sciences and Mathematics
New data from North Sea Upper Jurassic source rock samples show no decline in the total amount of organic matter (TOC) within the oil expulsion window between 120 and 150°C which is a key prediction by today’s model for oil expulsion. However, today’s model for oil expulsion is not consistent with either subsurface source rock TOC data or chemical attributes of shallow oils. Instead, these data [...]
Methane Fluxes of Vegetated Areas in Natural Freshwater Ecosystems: Assessments and Global Significance
Published: 2021-12-05
Subjects: Biogeochemistry, Earth Sciences, Environmental Sciences, Other Environmental Sciences
Freshwater ecosystems, including wetlands, lakes, and running waters, are estimated to contribute roughly 40% to global emissions of methane (CH4), a highly potent greenhouse gas. The emission of CH4 to the atmosphere entails the diffusive, ebullitive, and plant-mediated pathway. The latter, in particular, has been largely understudied and is neither well understood nor quantified. We have [...]
A copula-based assessment of renewable energy droughts across Europe
Published: 2021-12-05
Subjects: Multivariate Analysis, Oil, Gas, and Energy, Other Earth Sciences
Meeting carbon-reduction targets will require thorough consideration of climate variability and climate change due to the increasing share of climate-sensitive renewable energy sources (RES). One of the main concerns arises from situations of low renewable production and high demand, which can hinder the power system. We analysed energy droughts, defined as periods of low energy production (wind [...]
Supraglacial debris thickness and supply rate in High-Mountain Asia
Published: 2021-12-05
Subjects: Physical Sciences and Mathematics
Supraglacial debris strongly modulates glacier melt rates and can be decisive for ice dynamics and mountain hydrology. It is ubiquitous in High-Mountain Asia (HMA), yet because its thickness and supply rate from local topography are poorly known, our ability to forecast regional glacier change and streamflow is limited. Here we resolved the spatial distribution of supraglacial debris thickness [...]
Evidences of horizontal urban heat advection in London using 6 years of data from a citizen weather station network
Published: 2021-12-05
Subjects: Climate, Environmental Monitoring, Environmental Sciences, Meteorology, Physical and Environmental Geography
Recent advances in citizen weather station (CWS) networks, with data accessible via crowd-sourcing, provide relevant climatic information to urban scientists and decision makers. In particular, CWS can provide long-term measurements of urban heat and valuable information on spatio-temporal heterogeneity related to horizontal heat advection. In this study, we make the first compilation of a [...]
High-magnitude stresses induced by mineral-hydration reactions
Published: 2021-12-04
Subjects: Physical Sciences and Mathematics
Fluid-rock interactions play a critical role in Earth’s lithosphere and in engineered subsurface systems. In the absence of chemical mass transport, mineral-hydration reactions will be accompanied by a solid-volume increase that may induce differential stresses and associated reaction-induced deformation processes, such as dilatant fracturing to increase fluid permeability. However, the [...]
Thresholds in road network functioning on US Atlantic and Gulf barrier islands
Published: 2021-12-04
Subjects: Analysis, Geomorphology, Nature and Society Relations, Sustainability
Barrier islands predominate the Atlantic and Gulf coastlines of the USA, where development exceeds national trends. Forward-looking models of barrier island dynamics often include feedbacks with management practices – particularly those aimed at mitigating damage to buildings from natural hazards – and how real estate markets may be linked to barrier island dynamics. However, models thus far do [...]
Variable dynamic styles of primordial heterogeneity preservation in the Earth’s lower mantle
Published: 2021-12-04
Subjects: Physical Sciences and Mathematics
The evolution of the system Earth is critically influenced by the long-term dynamics, composition and structure of the mantle. While cosmochemical and geochemical constraints indicate that the lower mantle hosts an ancient primordial reservoir that may be enriched in SiO2 with respect to the upper mantle, geophysical observations and models point to efficient mass transfer and convective mixing [...]
Coupled dynamics and evolution of primordial and recycled heterogeneity in Earth’s lower mantle
Published: 2021-12-04
Subjects: Earth Sciences, Planetary Sciences
The nature of compositional heterogeneity in Earth’s lower mantle remains a long-standing puzzle that can inform about the long-term thermochemical evolution and dynamics of our planet. Here, we use global-scale 2D models of thermo- chemical mantle convection to investigate the coupled evolution and mixing of (intrinsically-dense) recycled and (intrinsically- strong) primordial heterogeneity in [...]
Corona structures driven by plume-lithosphere interactions and evidence for ongoing plume activity on Venus
Published: 2021-12-04
Subjects: Earth Sciences, Physical Sciences and Mathematics, Planetary Sciences
In the absence of global plate tectonics, mantle convection and plume-lithosphere interaction are the main drivers of surface deformation on Venus. Among documented tectonic structures, circular volcano-tectonic features known as coronae may be the clearest surface manifestations of mantle plumes and hold clues to the global Venusian tectonic regime. Yet, the exact processes underlying coronae [...]
Real Drivers of Climate Change?
Published: 2021-12-04
Subjects: Physical Sciences and Mathematics
As momentum gradually builds behind the strategy to address climate change through the global attainment of net zero emissions, recent science, post-dating this strategic implementation, throws doubt on the efficacy of such a strategy. Instead this science points to other potentially significant, if not primary, drivers of global warming largely overlooked by the established approach.
Competing feedback in an idealized tide-influenced delta network
Published: 2021-12-03
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
The morphodynamic evolution of river deltas is intimately tied to flow and sediment partitioning at bifurcations. In this work, the long-term equilibrium configuration of a simple delta network is investigated by means of an analytical model, which accounts for the effect of small tidal oscillations. Differently from individual bifurcations where tidal action is always a stabilizing factor, in [...]
Can machine learning improve carbon storage? Synergies of deep learning, uncertainty quantification and intelligent process control
Published: 2021-12-02
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Sustainability
As we transition from fossil fuel to renewable energy, negative emission technologies, such ascarbon capture and storage (CCS), can help us reduce CO2 emissions. Effective CO2 storage requires: (1) detailed site characterization, (2) regular, integrated risk assessment, and (3) flexible design and operation. We believe that recent advances in machine learning coupled with uncertainty [...]
An Online-Learned Neural Network Chemical Solver for Stable Long-Term Global Simulations of Atmospheric Chemistry
Published: 2021-12-02
Subjects: Engineering, Physical Sciences and Mathematics
A major computational barrier in global modeling of atmospheric chemistry is the numerical integration of the coupled kinetic equations describing the chemical mechanism. Machine-learned (ML) solvers can offer order-of-magnitude speedup relative to conventional implicit solvers, but past implementations have suffered from fast error growth and only run for short simulation times (<1 month). A [...]