Preprints
Filtering by Subject: Physical Sciences and Mathematics
Measures of deep-time terrestrial net ecosystem productivity and carbon sink function
Published: 2024-10-16
Subjects: Life Sciences, Physical Sciences and Mathematics
Indicators of past biological productivity, or ‘palaeoproductivity proxies’, offer ways to indirectly measure Earth’s deep-time ecosystem and carbon cycle functioning. Given that plants have been the principal primary producers on land for hundreds of millions of years, the abundances of fossil plants in the rock record can indicate past changes in net terrestrial ecosystem productivity (NTEP). [...]
The evidence for open magmatic system processes recorded in the crystal cargoes of lunar basalts 10057, 12038, 12043, 15085, 15556, and 70017
Published: 2024-10-16
Subjects: Physical Sciences and Mathematics
Basaltic magmatism is fundamental to planetary evolution, and continues to be studied in depth on Earth. Terrestrial studies indicate that basaltic magmatic systems are generally comprised of a series of batches with distinct compositions, which can be stored at depth within crystal frameworks, creating mushes. The crystal cargos of magmas erupted from such systems record evidence of the mush [...]
Global Rice Paddy Inventory (GRPI): a high-resolution inventory of methane emissions from rice agriculture based on Landsat satellite inundation data
Published: 2024-10-16
Subjects: Physical Sciences and Mathematics
Rice agriculture is a major source of atmospheric methane, but current emission inventories are highly uncertain, mostly due to poor rice-specific inundation data. Inversions of atmospheric methane observations can help to better quantify rice emissions but require high-resolution prior information on the location and timing of emissions. Here we use Landsat satellite data at 30 m resolution to [...]
Tracking glacier surge evolution using interferometric SAR coherence — examples from Svalbard
Published: 2024-10-14
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
We present a practically simple methodology for tracking glacier surge onset and evolution using interferometric Synthetic Aperture Radar (InSAR) coherence. Detecting surges early and monitoring their build-up is interesting for a multitude of scientific and safety-related aspects. We show that InSAR coherence maps allow the detection of surge-related instability on Svalbard many years before [...]
Preserved eolian bedforms control reservoir heterogeneity: characterization and modeling workflow for the Avilé Member, Neuquén Basin, Argentina
Published: 2024-10-11
Subjects: Physical Sciences and Mathematics
Under certain conditions, most commonly abrupt flooding events, entire eolian bedforms can be incorporated into the geological record. Sediment that was essentially ‘in transport’ within these bedforms at the time of preservation has a distinct sedimentary architecture compared to that of sensu stricto accumulated intervals. Despite this, while the preservation of bedforms has been readily [...]
Limited warming of Middle Miocene arid low-latitude climates: application of clumped isotopes in sabkha environments
Published: 2024-10-10
Subjects: Physical Sciences and Mathematics
Reconstructing past climatic conditions in arid and hot environments is challenging due to a scarcity of climate archives. However, this task is crucial for assessing the sensitivity of these areas to climate change. The lack of reliable proxies currently prevents precise and absolute temperature and moisture reconstructions. Clumped isotopes on sabkha calcite might alleviate this situation. In [...]
Modelling intra-parasequence reservoir heterogeneity with a process-mimicking algorithm: a case study from the Kenilworth Member, Blackhawk Formation
Published: 2024-10-09
Subjects: Physical Sciences and Mathematics
Wave dominated, shallow marine siliciclastic successions form some of the most prolific oil and gas reservoirs worldwide, where individual parasequences comprise the main flow units. Within parasequences, these reservoirs have been traditionally modelled as simple shore-parallel facies belts, given their reputation as simple reservoirs with subtle spatial heterogeneity in petrophysical [...]
A New Neural Network Retrieval of Liquid Water Path Optimized for Mixed-Phase Cold Air Outbreaks Using Radiometer and Radar Observations
Published: 2024-10-09
Subjects: Physical Sciences and Mathematics
Cold-air outbreaks over high latitude oceans typically include mixed-phase clouds and precipitation, in particular liquid clouds that support snow and graupel through ice growth processes. The partitioning of the total water into the liquid and ice phases impacts both weather and climate prediction, but accurate measurements on the phase partitioning remain difficult to acquire, especially [...]
Structural weaknesses in ice mélange revealed by high resolution ICEYE SAR imagery
Published: 2024-10-08
Subjects: Glaciology, Physical Sciences and Mathematics
The mixture of icebergs and sea ice in tidewater glacier fjords, known as ice mélange, is postulated to impact iceberg calving directly through physical buttressing and indirectly through freshwater fluxes altering fjord circulation. In this contribution, we assess the textural characteristics of ice mélange in summer and winter at the terminus of Helheim Glacier in Greenland using high [...]
Damped Gravity Waves, Weak Temperature Gradients, and Tropical Deep Convection
Published: 2024-10-02
Subjects: Physical Sciences and Mathematics
The "damped gravity wave" (DGW) approximation occurs when convective momentum dissipation is balanced by the pressure gradient force of convectively forced gravity waves. While this balance has been used to parameterize large-scale lifting in limited-domain models of tropical deep convection, its applicability to observed phenomena has not been carefully examined. A scale analysis indicates that [...]
Effect of organic coatings on optical properties of black carbon aerosol: Insights from Mie theory based model simulations
Published: 2024-10-01
Subjects: Physical Sciences and Mathematics
Black carbon (BC), plays a crucial role in climate change due to its significant impact on radiative forcing. This study investigates the influence of organic carbon (OC) coatings on the optical properties of BC aerosols using Mie theory-based calculations. We have examined a range of core diameters and coating thicknesses to assess changes in both absorption and scattering cross-sections. The [...]
Imaging a buried terrane with district-scale ambient noise tomography and gravity modelling: insights for scale-reduction in mineral exploration
Published: 2024-10-01
Subjects: Earth Sciences, Physical Sciences and Mathematics
Mineral exploration proceeds by a process of scale-reduction. Decisions need to be made at all stages as the physical search space becomes progressively reduced from regional through to district, camp and tenement/deposit scale. While there are many regional scale datasets available to explorers through public geoscience agencies, one of the most difficult steps to make is from the regional-scale [...]
Seismicity-constrained fault detection and characterization with a multitask machine learning model
Published: 2024-09-27
Subjects: Physical Sciences and Mathematics
Geological fault detection and characterization from geophysical data have been one of the center challenges in geophysics and seismology as it holds the key to understanding subsurface dynamics ranging from borehole, reservoir, to regional scales. While paradigms of auto or semi-auto fault delineation either based on seismicity location analysis or on seismic migration image reflector [...]
Groundwater use to reduce natural hazard susceptibilities and inequities in the metacrisis
Published: 2024-09-26
Subjects: Earth Sciences, Environmental Sciences, Hydrology, Physical Sciences and Mathematics
Long-term thinking is broadly advocated for groundwater - the largest available freshwater resource that is essential for drinking water, irrigation and ecosystems around the world. Long-term thinking is crucial to support sustainability of this slowly renewed resource, but here we propose another crucial, novel and emerging approach for groundwater: short-term use over days and months during or [...]
Regional Source-type Discrimination Using Nonlinear Alignment Algorithms
Published: 2024-09-26
Subjects: Physical Sciences and Mathematics
The discrimination problem in seismology aims to accurately classify different underground source types based on local, regional and/or teleseismic observations of ground motion. Typical discriminant approaches are rooted in fundamental, physics-based differences in radiation pattern or wave excitation, which can be frequency dependent and may not make use of the full waveform. In this paper, we [...]