Filtering by Subject: Earth Sciences
Published: 2022-04-14
Subjects: Climate, Earth Sciences, Geochemistry, Oceanography and Atmospheric Sciences and Meteorology
Southwestern North America, like many subtropical regions, is predicted to dry in response to anthropogenic warming. However, during the Pliocene, when carbon dioxide was above pre-industrial levels, southwestern North America was wetter. While existing explanations for a wet Pliocene invoke increases in winter rain, recent modeling studies hypothesize that summer rain also played an important [...]
Published: 2022-04-13
Subjects: Civil and Environmental Engineering, Earth Sciences, Education, Engineering, Engineering Education, Environmental Education, Environmental Engineering, Hydraulic Engineering, Hydrology, Numerical Analysis and Scientific Computing, Other Civil and Environmental Engineering, Physical Sciences and Mathematics, Science and Mathematics Education, Water Resource Management
Computational hydrological models and simulations are fundamental pieces of the workflow of contemporary hydroscience research, education, and professional engineering activities. In support of hydrological modelling efforts, web-enabled tools for data processing, storage, computation, and visualization have proliferated. Most of these efforts rely on server resources for computation and data [...]
Published: 2022-04-13
Subjects: Earth Sciences, Physical Sciences and Mathematics
Petrological data indicate that upper mantle and mantle plume temperatures diverged 2.5 billion years ago. This has been interpreted as plate tectonics initiating at 2.5 Ga with Earth operating as a single plate planet before then. We take an Occam’s razor view that the continuous operation of plate tectonics can explain the divergence. We validate this hypothesis by comparing petrological data [...]
Published: 2022-04-10
Subjects: Earth Sciences
The slow creeping motion of Earth’s mantle drives transient changes in surface topography across a variety of spatial and temporal scales. Recent decades have seen substantial progress in understanding this so-called `dynamic topography’, with a growing number of studies highlighting its fundamental role in shaping the surface of our planet. In this review, we outline the current frontiers of [...]
Published: 2022-04-07
Subjects: Earth Sciences, Sedimentology
The morphodynamics of ancient rivers can be reconstructed from fluvial stratigraphy using quantitative techniques to provide detailed insights into the driving forces behind the sedimentary systems. This work explores how these drivers can be evaluated from Paleozoic stratigraphy. Field measurements are taken in fluvial sediments from the Westphalian (Bolsovian and Asturian; 315.2–308 Ma) Pennant [...]
Published: 2022-04-07
Subjects: Earth Sciences, Materials Science and Engineering
In continuum mechanics, viscous materials are those that lack rigidity and elastic response under shear stress. We argue that using the term viscous to refer to the aseismic lithosphere is thus a misnomer, as it denies the propagation of S-waves through the lithosphere in total contradiction to decades of seismic surveys. Likewise, viscous materials lack yield stress, which is another feature [...]
Published: 2022-04-07
Subjects: Earth Sciences, Petroleum Engineering
Residual oil zones (ROZ) undergoing CO2-EOR may benefit from specific strategies to maximize their value. We evaluated several strategies for producing from a Permian Basin, West Texas, USA field’s ROZ. This ROZ lies below the main pay zone (MPZ) of the field. Such brownfield ROZs occur in the Permian Basin and elsewhere. Since brownfield ROZs are hydraulically connected to the MPZs, development [...]
Published: 2022-04-07
Subjects: Earth Sciences, Education
The Unlearning Racism in Geosciences (URGE) program guides groups of geoscientists as they draft, implement, and assess anti-racist policies and resources for their workplace. Some participating Geoscientists of Color (GoC) shared concerns about microaggression, tokenism, and power struggles within their groups. These reports led us to collect and analyze data that describe the experiences of GoC [...]
Published: 2022-04-06
Subjects: Earth Sciences
Countless continuously interacting processes determine the functioning and evolution of the Earth. Even geodynamic and climate changes, which have been classically studied independently because they pertain to different Earth ‘spheres’, are linked by mutual cause-effect relationships that recent research has just started to recognize and quantify. Modeling, be it analogue or numerical, is a trump [...]
Published: 2022-04-04
Subjects: Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology
Arctic sea ice loss has become a symbol of ongoing climate change, yet climate models still struggle to reproduce it accurately, let alone predict it. A reason for this is the increasingly clear role of the ocean, especially the "Atlantic layer", on sea ice processes. We here quantify biases in that Atlantic layer and the Arctic Ocean deeper layers in 14 representative models that participated in [...]
Published: 2022-04-02
Subjects: Earth Sciences, Physical Sciences and Mathematics
On Earth, the velocity at which subducting plates are consumed at their trenches (termed `subduction rate' herein) is typically 3 times higher than trench migration velocities. The subduction rate is also 5 times higher than estimated lower mantle slab sinking rates. Using simple kinematic analyses, we show that if this present-day ``kinematic state'' operated into the past, the subducting [...]
Published: 2022-04-02
Subjects: Earth Sciences, Environmental Monitoring, Environmental Sciences, Hydrology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Tide gauge records are commonly used as proxies to detect coastal floods and project future flood frequencies. While these proxies clearly show that sea-level rise will increase the frequency of coastal flooding, tide gauges do not account for land-based sources of coastal flooding and therefore likely underestimate the current and future frequency of coastal flooding. Here we present a new [...]
Published: 2022-04-02
Subjects: Earth Sciences, Physical Sciences and Mathematics
Lithium isotopes have emerged as a powerful tool to probe the response of global weathering to changes in climate. Due to the preferential incorporation of 6Li into clay minerals during chemical weathering, the isotope ratio δ7Li may be used to interrogate the balance of primary mineral dissolution and clay precipitation. This balance has been linked to relative rates of chemical and physical [...]
Published: 2022-04-01
Subjects: Applied Mathematics, Computer Sciences, Earth Sciences, Mathematics
Time-dependent ground deformation is a key observable in active magmatic systems, but is challenging to characterize. Here we present a numerical framework for modeling transient deformation and stress around a subsurface, spheroidal pressurized magma reservoir within a viscoelastic half-space with variable material coefficients, utilizing a high-order finite-element method and explicit [...]
Published: 2022-03-31
Subjects: Agricultural Science, Agriculture, Agronomy and Crop Sciences Life Sciences, Biochemistry, Biophysics, and Structural Biology, Earth Sciences, Environmental Sciences
Agricultural practices have created tens of millions of small artificial water bodies (“farm dams” or “agricultural ponds”) to provide water for domestic livestock worldwide. Among freshwater ecosystems, farm dams have some of the highest greenhouse gas (GHG) emissions per m2 due to fertilizer and manure run-off boosting methane production – an extremely potent GHG. However, management strategies [...]