Preprints
There are 5432 Preprints listed.
Kimberlite, carbonatite and alkaline magmatic systems: definitions, origins, and strategic mineral resources
Published: 2025-02-27
Subjects: Education
This Chapter provides an overview of the nature and origin of kimberlites, carbonatites and alkaline silicate rocks, with emphasis on the strategic mineral deposits linked to these types of mantle-derived volcanism (e.g., diamonds and rare-earth elements). It is demonstrated that many of the critical raw materials hosted by carbonatites and alkaline silicate rocks are essential for the transition [...]
A composite index-based insurance instrument for managing the financial risk of variable hydrometeorology for electric utilities
Published: 2025-02-27
Subjects: Civil and Environmental Engineering, Engineering
Variable hydrometeorological conditions can impact electric utilities' financial stability. Extreme temperatures often increase electricity demand, raising utility costs, while drought reduces hydropower generation and often reduces revenues, with financial impacts potentially exacerbated by spikes in fuel prices, particularly natural gas. In this study, a model of the U.S. West Coast power [...]
Influence of snowpack properties and local incidence angle on SAR signal depolarization: a mathematical model for high-resolution snow depth estimation
Published: 2025-02-26
Subjects: Remote Sensing
Recently, Dual-Polarimetric Synthetic Aperture Radar (SAR) has been shown to be effective for large-scale snow cover monitoring, but it faces significant challenges when applied to finer resolutions, which are crucial for applications such as avalanche forecasting. In this study, we propose a novel mathematical model to retrieve snow properties from Sentinel-1 SAR data, leveraging variations in [...]
Seismic imaging of mid-crustal heterogeneity beneath geothermal systems, central Taupo Volcanic Zone, New Zealand
Published: 2025-02-26
Subjects: Earth Sciences, Geophysics and Seismology
The Taupo Volcanic Zone (TVZ) in New Zealand is a region of highly pro- ductive Quaternary volcanism and very large hydrothermal heat flux. Here we investigate the upper- and mid-crustal seismic velocity structure of a region within the central, rhyolitic part of the TVZ encompassing the high- temperature geothermal systems Mokai, Wairakei, Ng¯a Tamariki, Orakei Korako, Te Kopia and Rotokawa. [...]
Patterns of deformation in the deepest mantle linked to ancient subduction
Published: 2025-02-25
Subjects: Physical Sciences and Mathematics
Shear wave speeds in Earth's deepest mantle (D") that vary with wave propagation and polarization direction -- a property called seismic anisotropy -- offer insights into mantle convection. To date, global patterns of D" anisotropy have been mostly derived from long wavelength radially anisotropic tomography models, which often disagree except for the large-scale degree-2 pattern. Here, we [...]
Aligning science and practice in evaluations of cookstove carbon projects
Published: 2025-02-25
Subjects: Environmental Studies, Social and Behavioral Sciences
Carbon markets are thought to be central to global climate strategies,1 but their scalability depends on the credibility of emissions reduction claims,2 a point that has recently faced scientific and public doubt.3,4 Carbon projects typically generate their own estimates of averted emissions to produce credits, a practice that introduces potential conflicts of interest and underscores the need [...]
Joint Optimization of Large and Small Models for Surface Temperature and Emissivity Retrieval Using Knowledge Distillation
Published: 2025-02-25
Subjects: Earth Sciences
The rapid advancement of artificial intelligence in domains such as natural language processing has catalyzed AI research across various fields. This study introduces a novel strategy, the AutoKeras-Knowledge Distillation (AK-KD), which integrates knowledge distillation technology for joint optimization of large and small models in the retrieval of surface temperature and emissivity using thermal [...]
Air quality impacts of the January 2025 Los Angeles wildfires: Insights from public data sources
Published: 2025-02-24
Subjects: Environmental Health and Protection
Smoke from the Los Angeles wildfires that started on January 7, 2025 caused severe air quality impacts across the region. Government agencies released guidance on assessing personal risk, pointing to publicly available data platforms that present information from regulatory and low-cost monitoring networks. Additional satellite-based products provide useful supplementary information during [...]
Middle Miocene Mediterranean mangroves and potential modern analogs
Published: 2025-02-24
Subjects: Paleontology
During the Miocene Climatic Optimum (MCO; 17–15 Ma), the northern boundary of mangroves – now situated at ~30° N – extended along the northern Mediterranean coasts (~45° N). These Avicennia-only mangroves have been considered impoverished mangroves controlled by the general latitudinal temperature gradient. The MCO Mediterranean mangroves have been compared with the extant Middle East (ME) [...]
Uncertainties as a Guide for Global Water Model Advancement
Published: 2025-02-24
Subjects: Environmental Sciences
Global water models increasingly allow us to explore the terrestrial water cycle in earth-sized digital laboratories to support science and guide policy. However, these models are still subject to considerable uncertainties that mainly originate from three sources: (1) imbalances in data quality and availability across geographical regions and between hydrologic variables, (2) poorly quantified [...]
Phytoplankton blooms in the new Southern Ocean sea ice regime
Published: 2025-02-24
Subjects: Biogeochemistry, Geophysics and Seismology, Oceanography
Over the last decade, the Antarctic sea ice extent has recorded record highs and lows. The anomalous low in 2023 suggested a new reduced sea-ice state, with unknown impacts on phytoplankton blooms, including phenology and magnitude. Analysing both Biogeochemical (BGC) and Core Argo floats, we compare annual sea ice extent (SIE) anomalies and sea ice volume (SIV) to physical and biological [...]
Trends and ENSO-related variability in Atlantic tropical cyclone intensity and intensification
Published: 2025-02-23
Subjects: Physical Sciences and Mathematics
Thirty Years of the Open Geospatial Consortium - History, Present, and Future
Published: 2025-02-23
Subjects: Engineering, Physical Sciences and Mathematics, Social and Behavioral Sciences
For 30 years, the Open Geospatial Consortium (OGC) has advanced geospatial interoperability through continuous innovation. The OGC provides strategies and Standards that promote adoption, increase efficiencies, create new opportunities, and transform our relationship with the dynamic planet we inhabit. It has fostered global collaborations among companies, governments, academic institutions, and [...]
Towards a global deep learning model for daily soil CO2 efflux
Published: 2025-02-21
Subjects: Life Sciences
Soil CO2 efflux, the largest flux of CO2 to the atmosphere, is expected to rise globally under climate change. Its magnitude and temporal variability are highly uncertain, and daily-scale models capturing rapid changes to environmental drivers remain rare. We used a global database of soil CO2 efflux (total observations = 7,797,535 from 2002-2020) to train a deep learning model (Long Short-Term [...]
The Role of Geospatial Intelligence in Modern Military Operations
Published: 2025-02-21
Subjects: Engineering, Physical Sciences and Mathematics
Geospatial intelligence (GEOINT) has become an indispensable tool in modern military operations since it considerably increases situational awareness, strategic decision-making, and operational success. Advanced geospatial technologies have changed military force collecting, analysis, and spatial data interpretation, including satellite imagery, remote sensing, geographic information systems [...]