Preprints
Filtering by Subject: Physical Sciences and Mathematics
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 [...]
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 [...]
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 [...]
Thermal budgets of magma storage constrained by diffusion chronometry: the Cerro Galán ignimbrite
Published: 2021-12-02
Subjects: Physical Sciences and Mathematics
The long-term thermochemical conditions at which large bodies of silicic magma are stored in the crust is integral to our understanding of the timing, frequency, and intensity of volcanic eruptions, and provides important context for interpreting volcano monitoring data. Despite this, however, individual magmatic systems may exhibit a range of time-temperature paths, or thermal histories, that [...]
Estuarine-deltaic controls on coastal carbon burial in the western Ganges-Brahmaputra delta over the last 5,000 years
Published: 2021-11-26
Subjects: Applied Statistics, Biogeochemistry, Earth Sciences, Environmental Sciences, Geochemistry, Geology, Geomorphology, Other Earth Sciences, Other Environmental Sciences, Other Statistics and Probability, Physical Sciences and Mathematics, Sedimentology, Statistical Methodology, Statistical Models, Statistics and Probability, Water Resource Management
The Ganges–Brahmaputra fluvial system drains the Himalayas and is one of the largest sources of terrestrial biosphere carbon to the ocean. It represents a major continental reservoir of CO2 associated with c. 1–2 billion tons of sediment transported each year. Shallow coastal environments receive substantial inputs of terrestrial carbon (900 Tg C yr−1), with allochthonous carbon capture on [...]
Conceptualizing the hydrogeothermal setting of Sloquet Hot Springs in the Canadian Cordillera on unceded St'at'imc Territory: an example of a reconciliation-based approach to field geoscience
Published: 2021-11-26
Subjects: Hydrology, Natural Resources Management and Policy, Physical Sciences and Mathematics
Field geoscience has made important scientific advances but has not consistently considered the impact of these geoscience results on communities where the fieldwork is conducted. A reconciliation-based approach calls for critical thought about who defines, participates in, owns, and uses geoscience research, particularly in light of unresolved aboriginal rights and title claims and treaty rights [...]
Accurate specification of water availability shows its importance for global crop production
Published: 2021-11-24
Subjects: Physical Sciences and Mathematics
It is well established that warming temperatures damage the yields of many crops across the globe. Yet the influence of water supply on global agricultural yield and its relation to water demand and direct temperature stress is unclear. A number of global studies found a minor influence for precipitation, whereas some regional analyses suggest a more prominent role for water availability. Here, [...]
A review of model-based scenario analysis of poverty for informing sustainability
Published: 2021-11-22
Subjects: Applied Mathematics, Dynamic Systems, Environmental Sciences, Natural Resources Management and Policy, Physical Sciences and Mathematics, Sustainability
Ending poverty in all its forms everywhere is the first goal being targeted by the United Nations 2030 Agenda for Sustainable Development. Poverty eradication is a long-term process that faces the challenges of many uncertainties and complex interactions with other Sustainable Development Goals (SDGs). In order to better understand poverty and contribute to addressing poverty in a sustainable [...]
The distinct problems of physical inconsistency and of multivariate bias potentially involved in the statistical adjustment of climate simulations
Published: 2021-11-22
Subjects: Physical Sciences and Mathematics
Bias adjustment of numerical climate model simulations involves several technical and epistemological arguments wherein the notion of physical inconsistency is often referred to, either for rejecting the legitimacy of bias adjustment in general or for justifying the necessity of sophisticated multivariate techniques. However, this notion is often mishandled, in part because the literature [...]
The Influence of Grain Shape and Size on the Relationship Between Porosity and Permeability in Sandstone
Published: 2021-11-18
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology
An accurate and reliable description of the relationship between porosity and permeability in geological materials is valuable in understanding subsurface fluid movement. This is of great importance for studies of reservoir characterisation, useful for energy exploitation, carbon capture, use and storage (CCUS) and groundwater contamination and remediation. Whilst the relationship between pore [...]
Rare allanite in granulitised eclogites constrains timing of eclogite to granulite facies transition in the Bhutan Himalaya
Published: 2021-11-15
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Tectonics and Structure
During continental collision, crustal rocks are buried, deformed, transformed and exhumed. The rates, timescales and tectonic implications of these processes are determined by linking geochemical, geochronological and microstructural data from metamorphic rock-forming and accessory minerals. Exposures of lower orogenic crust provide important insights into orogenic evolution, but are rare in [...]
Stable Silicon Isotopes Uncover a Mineralogical Control on the Benthic Silicon Cycle in the Arctic Barents Sea
Published: 2021-11-12
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Physical Sciences and Mathematics, Soil Science
Biogeochemical cycling of silicon (Si) in the Barents Sea is under considerable pressure from physical and chemical changes, including dramatic warming and sea ice retreat, together with a decline in dissolved silicic acid (DSi) concentrations of Atlantic inflow waters since 1990. Moreover, further expansion of the Atlantic realm (termed ‘Atlantification’) is expected to shift phytoplankton [...]
Insights into the mixing efficiency of submesoscale Centrifugal-Symmetric instabilities
Published: 2021-11-11
Subjects: Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Submesoscale processes provide a pathway for energy to transfer from the balanced circulation to turbulent dissipation. One class of submesoscale phenomena that has been shown to be particularly effective at removing energy from the balanced flow are centrifugal-symmetric instabilities (CSIs), which grow via geostrophic shear production. CSIs have been observed to generate significant mixing in [...]