Preprints
Filtering by Subject: Earth Sciences
Stable Silicon Isotopes Uncover a Mineralogical Control on the Benthic Silicon Cycle in the Arctic Barents Sea
Published: 2021-11-12
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Physical Sciences and Mathematics, Soil Science
Biogeochemical cycling of silicon (Si) in the Barents Sea is under considerable pressure from physical and chemical changes, including dramatic warming and sea ice retreat, together with a decline in dissolved silicic acid (DSi) concentrations of Atlantic inflow waters since 1990. Moreover, further expansion of the Atlantic realm (termed ‘Atlantification’) is expected to shift phytoplankton [...]
Streamlined subglacial bedform sensitivity to bed characteristics across the deglaciated Northern Hemisphere
Published: 2021-11-10
Subjects: Earth Sciences, Geology, Geomorphology, Glaciology
Streamlined subglacial bedforms observed in deglaciated landscapes provide the opportunity to assess the sensitivity of glacier dynamics to bed characteristics across broader spatiotemporal scales than is possible for contemporary glacial systems. While many studies of streamlined subglacial bedforms rely on manual mapping and qualitative (i.e., visual) assessment, we semi-automatically identify [...]
PbIso: an R package and web app for calculating and plotting Pb isotope data
Published: 2021-11-09
Subjects: Earth Sciences, Physical Sciences and Mathematics
The package PbIso is a free and open R toolbox for commonly used calculations and plots of Pb-Pb isotope data and for generating Pb evolution models. In this paper, we review Pb isotope systematics and the calculations that are commonly used, such as model age, model source
WlCount: Geological lamination detection and counting using an image analysis approach
Published: 2021-11-09
Subjects: Earth Sciences, Longitudinal Data Analysis and Time Series, Speleology, Stratigraphy
The manual identification and count of laminae in layered textures is a common practice in the study of geological records, which can be time consuming and carry large uncertainty for dense or disturbed lamina textures. We present here a novel image analysis approach to detect and count laminae in geoscientific imagery, called WlCount. Based on Dynamic Time Warping and Wavelet analysis, WlCount [...]
Open access in geochemistry from preprints to data sharing: past, present and future
Published: 2021-11-08
Subjects: Biogeochemistry, Cosmochemistry, Earth Sciences, Geochemistry, Volcanology
In this short communication, we discuss the latest advances regarding Open Access in the Earth Sciences and geochemistry community from preprints to findable, accessible, interoperable and reusable data following 14f session held at Goldschmidt conference (4-9 July 2021) dedicated to “Open Access in Earth Sciences”.
Simultaneous Inference of Plate Boundary Stresses and Mantle Rheology Using Adjoints: Large-Scale Two-Dimensional Models
Published: 2021-11-08
Subjects: Earth Sciences, Geophysics and Seismology, Numerical Analysis and Scientific Computing
Plate motions are a primary surface constraint on plate and mantle dynamics and rheology, plate boundary stresses, and the occurrence of great earthquakes. Within an optimization method, we use plate motion data to better constrain uncertain mantle parameters. For the optimization problem characterizing the maximum a posteriori rheological parameters we derive gradients using adjoints and [...]
Nonlinear time series analysis of palaeoclimate proxy records
Published: 2021-11-08
Subjects: Applied Statistics, Climate, Dynamic Systems, Earth Sciences, Geology, Longitudinal Data Analysis and Time Series, Multivariate Analysis, Non-linear Dynamics, Physical Sciences and Mathematics, Sedimentology, Statistical, Nonlinear, and Soft Matter Physics
Identifying and characterising dynamical regime shifts, critical transitions or potential tipping points in palaeoclimate time series is relevant for improving the understanding of often highly nonlinear Earth system dynamics. Beyond linear changes in time series properties such as mean, variance, or trend, these nonlinear regime shifts can manifest as changes in signal predictability, [...]
Subsurface temperature from seismic reflections: application to the post break up sequence offshore Namibia
Published: 2021-11-05
Subjects: Earth Sciences, Geology, Geophysics and Seismology
Accurate estimations of present-day subsurface temperatures are of critical importance to the energy industry, in particular with regards to geothermal energy and petroleum exploration. In frontier basins, the subsurface temperature regime can give an indication of the hydrocarbon potential of source horizons. The Lüderitz Basin, offshore Namibia, is a frontier deep water basin located on a [...]
Introducing StreamProfilerApp, a web application for near-global, exploratory, longitudinal river profile analysis
Published: 2021-11-03
Subjects: Earth Sciences, Education
Stream profile analysis has been used extensively in the earth sciences. In the past, exploration of stream profiles has required downloading and processing Digital Elevation Models (DEMs) for specific areas, which limits the scope of exploratory analysis. Presented here is a web application designed to analyze stream profiles at 90m resolution at a near-global scale. Based on the Hydrosheds [...]
Persistent shallow micro-seismicity at Llaima volcano, Chile, with implications for long-term monitoring
Published: 2021-11-01
Subjects: Earth Sciences, Geophysics and Seismology, Glaciology, Physical Sciences and Mathematics, Volcanology
Identifying the source mechanisms of low-frequency earthquakes at ice-covered volcanoes can be challenging due to overlapping characteristics of glacially and magmatically derived seismicity. Here we present an analysis of two months of seismic data from Llaima volcano, Chile, recorded by the permanent monitoring network in 2019. We find over 2,000 repeating low-frequency events split across 82 [...]
From offshore to onshore probabilistic tsunami hazard assessment via efficient Monte-Carlo sampling
Published: 2021-11-01
Subjects: Earth Sciences, Other Earth Sciences
Offshore Probabilistic Tsunami Hazard Assessments (offshore PTHAs) provide large-scale analyses of earthquake-tsunami frequencies and uncertainties in the deep ocean, but do not provide high-resolution onshore tsunami hazard information as required for many risk-management applications. To understand the implications of an offshore PTHA for the onshore hazard at any site, in principle the tsunami [...]
Airborne laser scanning proxies of canopy light transmission in forests
Published: 2021-10-29
Subjects: Biodiversity, Biogeochemistry, Computer Sciences, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Forest Sciences, Life Sciences, Physical Sciences and Mathematics, Plant Sciences, Software Engineering, Statistics and Probability
Reliable estimates of canopy light transmission are critical to understanding the structure and function of vegetation communities but are difficult and costly to attain by traditional field inventory methods. Airborne laser scanning (ALS) data uniquely provide multi-angular vertically resolved representation of canopy geometry across large geographic areas. While previous studies have proposed [...]
Bridging knowledge gaps with hybrid machine-learning forest ecosystem models (ML-FEMs): inferential simulation of past understory light regimes
Published: 2021-10-29
Subjects: Artificial Intelligence and Robotics, Biodiversity, Biogeochemistry, Computer Sciences, Earth Sciences, Ecology and Evolutionary Biology, Forest Sciences, Life Sciences, Physical Sciences and Mathematics, Plant Sciences
Soil moisture is a key limiting factor of plant productivity in boreal and montane regions, producing additional climate feedbacks through evaporation, regeneration, mortality, and respiration. Understory solar irradiation – the primary driver of surface temperature and evaporative demand – remains poorly represented in vegetation models due to a lack of 3-D canopy geometry. Existing models are [...]
Simulated decline of a northern forest due to anthropogenic controls on the regeneration-mortality balance
Published: 2021-10-29
Subjects: Biodiversity, Biogeochemistry, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Forest Sciences, Life Sciences, Physical Sciences and Mathematics, Plant Sciences
The population structure of forests is shaped by balancing the opposing forces of regeneration and mortality, each of which influence C turnover rates and are sensitive to climate. Regeneration underlies the migrational potential of forests to climatic change and remains underserved in modeling studies. Our objective was to test the hypothesis that warming may reduce tree regeneration rates while [...]
Emergence of anthropogenic fire regimes in the southern boreal of Canada
Published: 2021-10-29
Subjects: Biogeochemistry, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Forest Sciences, Life Sciences, Plant Sciences
While radiative forcing and thus land surface temperatures have been shown to positively correlate with fire severity, precipitation, and lightning strike frequency, the effects of human activity on fire regimes remain difficult to disentangle from geophysical drivers given co-variation between these factors. Here, I analyze fire regimes in the 1919-2012 period across Canada and compare national [...]