Preprints
Filtering by Subject: Physical Sciences and Mathematics
Process drivers, inter-model spread, and the path forward: A review of amplified Arctic warming
Published: 2021-09-15
Subjects: Physical Sciences and Mathematics
Arctic amplification (AA) is a coupled atmosphere-sea ice-ocean process. This understanding has evolved from the early concept of AA, as a consequence of snow-ice line progressions, through more than a century of research that has clarified the relevant processes and driving mechanisms of AA. The predictions made by early modeling studies, namely the fall/winter maximum, bottom-heavy structure, [...]
Discovery of Deccan Inclination Anomaly and its possible geodynamic implications over the Indian Plate
Published: 2021-09-13
Subjects: Physical Sciences and Mathematics
The rapid northward drift of the Indian plate during Deccan volcanism assumes a gradual shallowing of paleomagnetic inclinations in subsequent lava flow formations. A comparison of palaeomagnetic data produced during the last six decades reveals an inclination anomaly during Chron C29r (66.398 - 65.688 Ma) along with brief clockwise-counter-clockwise rotations during and after the main phase [...]
Three-dimensional fluid-driven stable frictional ruptures
Published: 2021-09-13
Subjects: Earth Sciences, Engineering, Environmental Sciences, Geophysics and Seismology, Oil, Gas, and Energy, Physical Sciences and Mathematics, Physics
We investigate the quasi-static growth of a fluid-driven frictional shear crack that propagates in mixed mode (II+III) on a planar fault interface that separates two identical half-spaces of a three-dimensional solid. The fault interface is characterized by a shear strength equal to the product of a constant friction coefficient and the local effective normal stress. Fluid is injected into the [...]
On the asymmetry of cyclones and anticyclones in the cellular regime of rotating Rayleigh-Bénard convection
Published: 2021-09-12
Subjects: Physical Sciences and Mathematics
Rotating Rayleigh-Bénard convection (RRBC) denotes the free convection between two parallel plates with a fixed temperature difference, placed in a rotating reference frame. It is a prototype model of geophysical and astrophysical convection. Rotation breaks the symmetry on its rotating axis, making the cyclones and anticyclones unequal in size and magnitude. Such an asymmetry has long been [...]
Streambed pollution: A comprehensive review of its sources, eco-hydro-geo-chemical impacts, assessment, and mitigation strategies
Published: 2021-09-10
Subjects: Engineering, Physical Sciences and Mathematics
Streambeds are an integral component of the river ecosystems. It provides habitat for a vast array of benthic and aquatic organisms as well as facilitates the bio-degradation and transformation of organic matter and other nutrients. Increasing anthropogenic influence introduces multiple stressors to the stream networks resulting in pollution of streambeds, which in turn, could have detrimental [...]
Integrating the ‘the triangle of geography, geology and geophysics’ into sustainable development
Published: 2021-09-10
Subjects: Education, Physical Sciences and Mathematics
In the context of tackling climate change in the eastern Mediterranean and Middle East, HRH Prince El-Hassan bin Talal has called for an integrated approach to human and natu-ral resources management that takes account of ‘the triangle of geography, geology and geophysics’. The lack of application of geoscientific knowledge to sustainable develop-ment issues is surprising given that advancing [...]
Inhibition of photoferrotrophy by nitric oxide in ferruginous environments
Published: 2021-09-10
Subjects: Physical Sciences and Mathematics
Anoxygenic phototrophic Fe(II)-oxidizers (photoferrotrophs) are thought to have thrived in Earth’s ancient ferruginous oceans and played a primary role in the precipitation of Archean and Paleoproterozoic (3.8-1.85 Ga) banded iron formations (BIF). The end of BIF deposition by photoferrotrophs has often been interpreted as being the result a deepening of water column oxygenation below the photic [...]
Thrusts control the thermal maturity of accreted sediments
Published: 2021-09-08
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
Thermal maturity assessments of hydrocarbon-generation potential and thermal history rarely consider how upper-plate structures developing during subduction influence the trajectories of accreted sediments. Our thermomechanical models of subduction support that thrusts evolving under variable sedimentation rates and décollement strengths fundamentally influence the trajectory, temperature, and [...]
Higher Long-Term Soil Moisture Increases Organic Carbon Accrual Through Microbial Conversion of Organic Inputs
Published: 2021-09-08
Subjects: Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics
High long-term soil moisture may either stimulate or inhibit soil organic carbon (SOC) losses through changes to mineral and chemical composition, and resultant organo-mineral interactions. Yet, the trade-off between mineralization and accrual of SOC under long-term variation in unsaturated soil moisture remains an uncertainty. In this study, we tested the underexplored relationships between [...]
Interannual variability in methane and nitrous oxide concentrations and sea-air fluxes across the North American Arctic Ocean (2015–2019)
Published: 2021-09-07
Subjects: Physical Sciences and Mathematics
Between 2015–2018, we collected approximately 2000 water column measurements of methane (CH4) and nitrous oxide (N2O) concentrations in the North American Arctic Ocean during summer and early fall. We also obtained 25 measurements of CH4 and N2O concentrations in rivers along the Northwest Passage and Ellesmere Island in mid-summer 2017–2019. Our results show that N2O is generated in the highly [...]
Lowermost mantle shear-velocity structure from hierarchical trans-dimensional Bayesian tomography
Published: 2021-09-05
Subjects: Earth Sciences, Physical Sciences and Mathematics
The core-mantle boundary (CMB) is the most extreme boundary within the Earth where the liquid, iron-rich outer core interacts with the rocky, silicate mantle. The nature of the lowermost mantle atop the CMB, and its role in mantle dynamics, is not completely understood. Various regional studies have documented significant heterogeneities at different spatial scales. While there is a consensus on [...]
Recharge observations indicate strengthened groundwater connection to surface fluxes
Published: 2021-09-03
Subjects: Physical Sciences and Mathematics
Groundwater is an invaluable global resource, but its long-term viability as a resource for consumption, agriculture, and ecosystems depends on precipitation recharging aquifers. How much precipitation recharges groundwaters varies enormously across Earth's surface, but recharge rates are uncertain because field observations are sparse and modeled global estimates remain largely unvalidated. Here [...]
CCREM: New reference Earth model from the global coda-correlation wavefield
Published: 2021-09-02
Subjects: Earth Sciences, Physical Sciences and Mathematics
The existing Earth reference models have provided an excellent one-dimensional representation of Earth’s properties as a function of its radius and explained many seismic observations in a broad frequency band. However, some discrepancies still exist among these models near the first-order discontinuities (e.g., the core-mantle and the inner-core boundaries) due to different datasets and [...]
An overview of multimethod imaging approaches in environmental geophysics
Published: 2021-08-30
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Quantitative characterization of subsurface properties is critical for many environmental applications and serves as the basis to simulate and better understand dynamic subsurface processes. Geophysical imaging methods allow to image subsurface property distributions and monitor their spatio-temporal changes in a minimally invasive manner. While it is widely agreed upon that models integrating [...]
Pedogenic processes and the drying of Mars
Published: 2021-08-30
Subjects: Physical Sciences and Mathematics
What exactly caused Mars to lose its liquid water billions of years ago remains as one of the most enduring questions in planetary science. New insights from Mars suggest that crustal hydration – the formation of hydrated minerals during aqueous alteration of the crust – contributed to the long-term drying of the planet. Here, we advance the hypothesis that hydration of the Martian crust could [...]