Preprints
There are 6138 Preprints listed.
Pre-Cordilleran mantle metasomatism preserved in alkali basalts of Isla Isabel, México
Published: 2024-07-09
Subjects: Geochemistry, Geology
The presence of HIMU (high-238U/204Pb) signatures in ocean island basalts has long been used to argue that ancient oceanic crust has been tectonically recycled into the mantle sources of plume-derived volcanic hotspots such as St. Helena or Mangaia. However, alternative hypotheses regarding the origins of HIMU signatures have also been put forward. This paper addresses the origins of HIMU-like Pb [...]
A non-equilibrium slurry model for planetary cores with application to Earth’s F-layer
Published: 2024-07-09
Subjects: Earth Sciences, Fluid Dynamics, Geophysics and Seismology, Mineral Physics
Slurry regions may exist in the cores of several terrestrial bodies and are expected to influence the dynamics of deep planetary interiors and the viability of maintaining global magnetic fields. Here we develop a two-component slurry model of the lowermost outer core of the Earth (the F-layer). In contrast to most previous models of slurries in planetary cores, we explicitly model the [...]
Satellite survey sheds new light on global solid waste methane emissions
Published: 2024-07-09
Subjects: Atmospheric Sciences, Environmental Sciences
Anthropogenic methane emissions are the second most important contributor to climate change, and their rapid reductions could help decrease near-term warming. Solid waste emits methane through the decay of organic material, which amounts to about 10% of total anthropogenic methane emissions. Satellite instruments enable monitoring of strong methane hotspots, including many strongly emitting urban [...]
Evaluating the Flood Vulnerability of Urban Areas in Polk County, Iowa using Social-Ecological-Technological Framework
Published: 2024-07-08
Subjects: Civil and Environmental Engineering, Risk Analysis
The escalating prominence of floods globally, with their catastrophic potential to inflict substantial losses in terms of both human lives and economic resources, underscores their significance. Particularly susceptible to flooding between May and July, the US Midwest faces heightened risks during this critical period, characterized by the highest average precipitation rates of the year. Flood [...]
Excitable Dynamics of Neoproterozoic to Early Paleozoic Atmospheric and Ocean Oxygen
Published: 2024-07-05
Subjects: Biogeochemistry
The geochemical carbon isotope and redox proxy record indicates that Earth’s surface oxygenation involved a prolonged period of extreme variability in atmospheric and oceanic oxygen, spanning from the early Neoproterozoic to the early Paleozoic. This variability has been linked to external tectonic and evolutionary forcings, as well as to internal nonlinear feedbacks related to the [...]
Building quantitative skills with a simplified physical model of coastal storm deposition
Published: 2024-07-04
Subjects: Earth Sciences, Educational Methods, Geomorphology, Higher Education, Scholarship of Teaching and Learning
This article describes an exercise for a physical laboratory experiment designed to enable physical geography students to practice transferrable quantitative skills through inquiry-based learning. The exercise is a deliberately simplified physical model of storm-driven coastal overwash typical of low-lying coastal barrier systems. The experiment can be trialled in anything from a baking pan or [...]
Uranium-series isotopes as tracers of physical and chemical weathering in glacial sediments from Taylor Valley, Antarctica
Published: 2024-07-04
Subjects: Earth Sciences, Geochemistry, Glaciology, Soil Science
The McMurdo Dry Valleys of Antarctica formed by extensive glacial erosion, yet currently exhibit hyperarid polar conditions characterized by limited chemical and physical weathering. Efficient chemical weathering occurs when moisture is available, and polythermal subglacial conditions may accommodate ongoing mechanical weathering and valley incision. Taylor Valley hosts several Pleistocene [...]
Micro-Scale Mapping of Soil Organic Carbon: The Potential of Soft X-Ray Spectromicroscopy
Published: 2024-07-04
Subjects: Agriculture, Environmental Sciences, Soil Science
Soil organic carbon (SOC) plays a crucial role in soil fertility, productivity, and global carbon cycling. However, the mechanisms governing SOC persistence and turnover are not fully understood, hindering effective carbon management strategies. Especially limiting are challenges to visualize and characterize spatial distribution patterns of SOC within the intact soil. This study presents a novel [...]
Unraveling the crop yield response under ... through the deployment of a drought index
Published: 2024-07-04
Subjects: Engineering
Extensive research has explored the impact of shading on vegetation growth and crop yield (CY) under agrivoltaic (APV) systems. These studies have revealed a notable connection between shading and CYs, with certain crop varieties showing benefits from shadings e.g., Berries and Leafy Vegetables, Forage remaining largely unaffected, and some crops e.g., Cereals, Grain Legumes, Fruits, and Root [...]
Mechanisms for upstream migration of firn aquifer drainage: preliminary observations of Helheim Glacier, Greenland
Published: 2024-07-03
Subjects: Glaciology
Surface meltwater can influence subglacial hydrology and ice dynamics if it reaches the ice sheet’s base. Firn aquifers store meltwater and drain into wide crevasses marking the aquifer’s downstream boundary, indicating water from firn aquifers drives hydrofracture to establish the upglacier-most surface-to-bed hydraulic connections. Yet, sparse observations limit our understanding of the [...]
Increasingly seasonal jet stream raises risk of co-occurring flooding and extreme wind in Great Britain
Published: 2024-07-03
Subjects: Applied Statistics, Atmospheric Sciences, Climate, Hydrology, Multivariate Analysis
Insurers and risk managers for critical infrastructure such as transport or power networks typically do not account for flooding and extreme winds happening at the same time in their quantitative risk assessments. We explore this potentially critical underestimation of risk from these co-occurring hazards through studying events using the regional 12 km resolution UK Climate Projections for a [...]
Probability of Detection and Multi-Sensor Persistence of Methane Emissions from Coincident Airborne and Satellite Observations
Published: 2024-07-02
Subjects: Physical Sciences and Mathematics
Satellites are becoming a widely used measurement tool for methane detection and quantification. The landscape of satellite instruments with some methane point-source quantification capabilities is growing. Combining information across available sensor platforms could be pivotal for understanding trends and uncertainties in source-level emissions. However, to effectively combine information [...]
Littoral activity in the lava deltas of 2021 eruption on Cumbre Vieja Volcanic Rift, La Palma (Canary Islands): constraints on explosive water-magma interaction
Published: 2024-07-01
Subjects: Earth Sciences
Tephra jets are a characteristic explosive phenomenon of lava deltas built by pāhoehoe or ‘a‘ā lava flows. Field observations made during the growth of the 2021 South Lava Delta (La Palma island), emplaced under a 100–150 m high marine cliff, show tephra jets driven by penetration of seawater through the external lava breccia into the interior of ‘a‘ā lava flows entering the ocean. However, this [...]
A scalable monitoring framework for leaf area index and green area index using 30°-tilted cameras
Published: 2024-07-01
Subjects: Terrestrial and Aquatic Ecology
• Leaf area index (LAI) and green area index (GAI) are fundamental plant traits. However, there is a lack of ground observation network for LAI/GAI due to technical limitations. Here we present a new method to achieve continuous LAI/GAI monitoring using ordinary cameras. • By tilting ordinary cameras by 30°, images can cover a large view zenith angle range to measure multi-angular gap fractions [...]
Machine Learning-based Hydrological Models for Flash Floods: A Systematic Literature Review
Published: 2024-07-01
Subjects: Hydrology
Flash floods are critical events for emergency management, yet their modeling remains highly challenging, even in smart cities approaches. Physically based hydrological models are often unsuitable at small spatiotemporal scales due to their computational complexity and dependence on detailed local parameters, which are rarely available during flash floods. With the growing availability of [...]