Preprints
Filtering by Subject: Physical Sciences and Mathematics
Evaluation of the Time Series Transformer Model and ESA-CCI PFT Dataset v2.0.8 for Upscaling Global Gross Primary Productivity
Published: 2023-12-05
Subjects: Earth Sciences, Physical Sciences and Mathematics
Accurate terrestrial gross primary productivity (GPP) estimates are crucial for developing effective climate change policies. However, quantifying GPP is challenging due to sparse ground observations and the complexity of plant functional types (PFTs). In this study, we address these challenges by evaluating various aspects of a data-driven model, including the architecture of time series deep [...]
Multiple dikes make eruptions easy
Published: 2023-12-04
Subjects: Physical Sciences and Mathematics
Dikes supply magma to most volcanic eruptions. Understanding how propagating dikes may, or may not, reach the surface is thus one of the fundamental tasks for volcanology. Many, perhaps most, dike segments injected from magma sources do not reach the surface to feed volcanic eruptions. Instead, the dike segments become arrested (stop their propagation), commonly at or close to contacts between [...]
Towards an Integrated Texture Toolkit, 1: Unveiling the Complex Relationship Between Crystal Size, Shape, and Fabric in EBSD Data
Published: 2023-12-04
Subjects: Physical Sciences and Mathematics
Rock textures observed via thin section are skewed from their true 3D nature. This is due to a variety of cut effects—artifacts that are introduced due to the lower dimensional nature of the thin section relative to the rock. Typically, these methods invert crystal shape and crystal size, but with each process performed separately and in sequence. With the ongoing adoption of electron backscatter [...]
A study of extreme water waves using a hierarchy of models based on potential-flow theory
Published: 2023-12-02
Subjects: Applied Mathematics, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Partial Differential Equations, Physical Sciences and Mathematics
The formation of extreme waves arising from the interaction of three line-solitons with equal far-field amplitudes is examined through a hierarchy of water-wave models. The Kadomtsev-Petviashvili equation (KPE) is first used to prove analytically that its exact three-soliton solution has a ninefold maximum amplification that is achieved in the absence of spatial divergence. Reproducing this [...]
Downslope weakening of soil revealed by a rapid robotic rheometer
Published: 2023-11-30
Subjects: Physical Sciences and Mathematics
Moving down a hillslope from ridge to valley, soil develops and becomes increasingly weathered. Downslope variation in clay content, organic matter, and porosity should produce concomitant changes in soil strength that influence slope stability and erosion. This has yet to be demonstrated, however, because in-situ measurements of soil rheology are challenging and rare. Here we employ a robotic [...]
Potential Volcanic Origin of the 2023 short-period Tsunami in the Izu Islands, Japan
Published: 2023-11-29
Subjects: Physical Sciences and Mathematics
On October 8, 2023, at 21:40 UTC (6:40 on October 9 local time), a tsunami warning was declared for the Izu Islands and southwest Japan. This tsunami was initially considered to be associated with the M4.9 earthquake at 20:25 UTC (5:25 JST). However, we know events of this magnitude are far too small to generate observed tsunamis from coseismic deformation alone. In this study, we analyzed the [...]
A Review of Measurement for Quantification of Carbon Dioxide Removal by Enhanced Weathering in Soil
Published: 2023-11-28
Subjects: Physical Sciences and Mathematics
All pathways which limit global temperature rise to <2oC above pre-industrial temperatures now require carbon dioxide removal (CDR) in addition to rapid greenhouse gas emissions reductions. Novel and durable CDR strategies need to rapidly scale over the next few decades in order to reach Paris Agreement Targets. Terrestrial enhanced weathering (EW) involves the acceleration of natural [...]
ICESat-2 and ocean particulates: Building a roadmap for calculating Kd from space-based lidar photon profiles
Published: 2023-11-28
Subjects: Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Planetary Sciences
ICESat-2’s Advanced Topographic Laser Altimeter System (ATLAS) has emerged as useful tool for calculating attenuation signals in natural surface waters, thus improving our understanding of particulates from open-ocean plankton to nearshore suspended terrigenous sediments. While several studies have employed methods based on Beer’s Law to derive attenuation coefficients (including through a [...]
Plagioclase-saturated melt hygrothermobarometry and plagioclase-melt equilibria using machine learning
Published: 2023-11-23
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Volcanology
Compositions of plagioclase-melt pairs are commonly used to constrain temperatures (T), dissolved water contents (H2O) and pressures (P) of pre-eruptive magma storage and transport. However, previous plagioclase-based thermometers, hygrometers, and barometers can have significant errors, leading to imprecise reconstructions of conditions during plagioclase growth. Here, we explore whether we can [...]
Towards parameterizing eddy-mediated transport of Warm Deep Water across the Weddell Sea continental slope
Published: 2023-11-23
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The transport of Warm Deep Water (WDW) onto the Weddell Sea continental shelf is associated with a heat flux and strongly contributes to the melting of Antarctic ice shelves. The small radius of deformation at high latitudes makes it difficult to accurately represent the eddy-driven component of onshore WDW transport in coarse-resolution ocean models so that a parameterization becomes necessary. [...]
Diurnal Warm Layers in the ocean: Energetics, non-dimensional scaling, and parameterization
Published: 2023-11-22
Subjects: Physical Sciences and Mathematics
Diurnal Warm Layers (DWLs) form near the surface of the ocean on days with strong solar radiation, weak to moderate winds, and small surface-wave effects. Here, we use idealized second-moment turbulence modelling, validated with Large Eddy Simulations (LES), to study the properties, dynamics and energetics of DWLs across the entire physically relevant parameter space. Both types of models include [...]
Luminescence Profiling and Flood Sediments from an Arctic Lake Over the Last Millenia
Published: 2023-11-22
Subjects: Physical Sciences and Mathematics
A small Arctic floodplain-lake (Tendammen, Colesdalen valley) in Svalbard revealed a laminated sediment sequence with numerous 14C AMS age-depth reversals in its 800 year history. In order to test the hypothesis that the anomalous dates result from catchment erosion and the deposition of reworked sediment and macrofossils, we applied luminescence profiling and flood-sensitive biological proxies. [...]
Calculating Standardised Indices Using SEI
Published: 2023-11-21
Subjects: Physical Sciences and Mathematics
Standardised indices are measurements of variables on a standardised scale. The standardised scale facilitates comparisons between different variables, and its probabilistic interpretation means the indices are effective for risk management and decision making. Standardised indices have become popular in weather and climate settings, for example within operational drought monitoring systems, and [...]
Evidence that seismic anisotropy captures upstream palaeo ice fabric: Implications on present day deformation at Whillans Ice Stream, Antarctica
Published: 2023-11-16
Subjects: Earth Sciences, Geophysics and Seismology, Glaciology, Physical Sciences and Mathematics
Understanding deformation and slip at ice streams, which are responsible for 90% of Antarctic ice loss, is vital for accurately modelling large-scale ice flow. Ice crystal orientation fabric (COF) has a first-order effect on ice stream deformation. For the first time, we use shear-wave splitting (SWS) measurements of basal icequakes at Whillans Ice Stream (WIS), Antarctica, to determine a [...]
Downsystem Grain-Size Trends and Mass Balance of an Ancient Wave-Influenced Sediment Routing System: Middle Jurassic Brent Delta, Northern North Sea, Offshore UK and Norway
Published: 2023-11-14
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
We reconstruct upsystem-to-downsystem grain-size variations in the sediment routing systems of the data-rich Middle Jurassic Brent Group of the northern North Sea, using published stratigraphic, thickness, palaeogeographic, provenance and age constraints combined with representative core and wireline-log data. Facies associations provide a textural proxy for gravel, sand and mud grain-size [...]