Preprints
Filtering by Subject: Earth Sciences
Field Report No. 2 - Tabor Tree Project: Citizen Scientists Training
Published: 2023-10-10
Subjects: Adult and Continuing Education, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Outdoor Education, Physical Sciences and Mathematics
“NASA’s citizen science projects are collaborations between scientists and interested members of the public. Through these collaborations, volunteers (known as citizen scientists) have helped make thou- sands of important scientific discoveries.” (NASA) In January 2021, using the GLOBE Observer app, the Mt. Tabor community joined this global network of scientists, students, teachers, hikers, and [...]
Field Report No. 1 - Tabor Tree Project Report 2021
Published: 2023-10-10
Subjects: Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Environmental Studies, Nature and Society Relations, Other Plant Sciences
In this Survey, the Tabor Tree Project identified 130 trees randomly in all 12 zones of the park called Mt. Tabor in Portland, Oregon. The Majority of the Trees at Mt. Tabor Park are conifers, and specifically Douglas Fir who can live longer than 1,000 years. The oldest one in the park is 496 years old, and sprouted sometime around 1520 AD. Through the efforts of Tree Medicine hikes and Citizen [...]
Rano Kao & Ava Ranga Uka: Rapa Nui Report 2014
Published: 2023-10-10
Subjects: Atmospheric Sciences, Climate, Earth Sciences, Environmental Sciences, Fresh Water Studies
29 March 2014 Objective: Sampling and testing Rano Kao water depth, evaporation and volume. Compare with previous results from 2005, 2008 and 2014 coring expeditions and detect the rate of change in lake water evaporation as compared to Global Meteoric Water Line.
The influence of fluid inclusions, organics, and calcite fabric on trace element distributions in stalagmites
Published: 2023-10-09
Subjects: Earth Sciences, Physical Sciences and Mathematics
Growing stalagmites entrap water and organic molecules while incorporating trace elements in diverse crystallographic fabrics. However, the interrelationships between crystal defects, fluid inclusions, organic carbon incorporation, and trace element incorporation in stalagmites remain poorly constrained. Here we use for the first time Fourier Transformation Infrared Focal-Plane Array (FTIR-FPA) [...]
Progression of the surge in the Negribreen Glacier System from two years of ICESat-2 measurements
Published: 2023-10-08
Subjects: Applied Mathematics, Earth Sciences, Physical Sciences and Mathematics
The unique measurement capabilities of ICESat-2 allow high spatiotemporal resolution of complex ice-dynamic processes that occur during a surge. Detailed and precise mapping of height changes on surge glaciers has previously escaped observations from space due to limited resolution of space-borne altimeter data and the surface characteristics of glaciers during surge such as heavy crevassing. [...]
The importance of anisotropic viscosity in numerical models for olivine textures in shear and subduction deformations
Published: 2023-10-05
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Olivine lattice preferred orientation (LPO), or texture, forms in relation to deformation mechanisms such as dislocation creep and can be observed in the upper mantle as seismic anisotropy. Olivine is also mechanically anisotropic, meaning that it responds to stresses differently depending on the direction of the stress. Understanding the interplay between anisotropic viscosity (AV) and LPO, and [...]
Monitoring surface deformation with spaceborne radar interferometry in landslide complexes: insights from the Brienz/Brinzauls slope instability, Swiss Alps
Published: 2023-10-05
Subjects: Earth Sciences
We performed an extensive analysis of C-Band SAR datasets provided by the European Space Agency (ESA) satellites ERS-1/2, Envisat ASAR, and Sentinel-1 in the period 1992-2020 aiming at reconstructing the multi-decadal spatial and temporal evolution of the surface displacements at the Brienz/Brinzauls landslide complex, located in canton Graubünden (Switzerland). To this end, we analyzed about [...]
A shift in the Sr isotopic composition of the magmatic source triggering 2019 paroxysmal eruptions at Stromboli Volcano
Published: 2023-10-05
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics, Volcanology
The persistent volcanic activity of Stromboli Volcano, Aeolian Islands, Italy, is interrupted by paroxysmal eruptions on a decadal interval. In 2019, two strong paroxysms on July 3rd and August 28th, ended a more than a decade long period of regular strombolian activity. During normal strombolian activity the volcano erupts highly porphyritic scoria and lava (HP)20 with a shoshonitic basalt [...]
Complementary classifications of aeolian dunes based on morphology, dynamics, and fluid mechanics
Published: 2023-10-03
Subjects: Earth Sciences, Fluid Dynamics, Geomorphology, Other Earth Sciences, Physical Sciences and Mathematics, Physics, Planetary Geomorphology, Planetary Sciences, Sedimentology
Dunes form where winds blow over a bed of mobile sediment grains – conditions that are common in our solar system. On Earth, dunes abound in arid continental interiors and along sandy coastlines. Dune fields have also been recognized on Venus, Mars, Saturn's moon Titan, and Pluto. In response to the different boundary conditions and other environmental forcings, dunes adopt a rich diversity [...]
Geological evidence confirms the staircase patterns of Earth’s rotation deceleration from the Neoproterozoic to the Mesozoic Era
Published: 2023-10-02
Subjects: Earth Sciences, Environmental Sciences
Due to tidal dissipation, the Earth’s rotation has been slowing down, but the past rates of this process remain subject of debate. Here we conducted a comprehensive cyclostratigraphic analysis of eight geological datasets to further constrain the Earth's rotation history from the Neoproterozoic to Mesozoic. Our results allow us to further test theoretical physical tidal models, and support a [...]
Revisiting oxygen-18 and clumped isotopes in planktic and benthic foraminifera
Published: 2023-09-27
Subjects: Earth Sciences, Environmental Sciences
Foraminiferal isotopes are widely used to study past oceans, with different species recording conditions at different depths. Their δ18O values record both seawater oxygen-18 and temperature according to species-specific fractionation factors, while their Δ47 signatures likely depend only on temperature. We describe an open-source framework to collect/combine data relevant to foraminiferal [...]
The Balanced Billion
Published: 2023-09-27
Subjects: Earth Sciences
There is a mid-Proterozoic stretch of Earth’s history (roughly 1.9–0.9 Ga) called, non-affectionately, the “boring billion”. The moniker was first inspired several decades ago by the apparent absence of any significant carbon isotope anomalies and was linked to the relatively “boring” interval in between Earth’s broadly two-step pattern in atmospheric oxygenation. However, in light of (i) the [...]
No respite from permafrost-thaw impacts in absence of a global tipping point
Published: 2023-09-25
Subjects: Biogeochemistry, Climate, Earth Sciences, Geomorphology, Hydrology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Arctic permafrost, the largest non-seasonal component of Earth’s cryosphere, contains a significant climate-sensitive carbon pool. Its potential for loss due to climatic changes leading to a global tipping point, where thawing accelerates with disproportionate impacts, remains debated. Here, we provide an integrative perspective on this question, building on a cross-disciplinary meta-analysis of [...]
Accuracy of UAV mapping of Natura 2000 forest, wetland and grassland habitats: Do we need more seasons or more spectral bands?
Published: 2023-09-22
Subjects: Biodiversity, Earth Sciences, Environmental Sciences, Research Methods in Life Sciences
Mapping and monitoring of Natura 2000 habitats (Habitat Directive 92/43/EEC) is one of the key activities to ensure the protection of natural habitats in Europe. Remote sensing can help to acquire high-quality maps of the distribution and conservation status of Natura 2000 habitats, for example through classifying multispectral data. However, due to the high number of habitats (classes) [...]
Omnivariant Generalized Least Squares Regression: Theory, Geochronological Applications, and Making the Case for Reconciled Δ47 calibrations
Published: 2023-09-22
Subjects: Applied Mathematics, Earth Sciences, Geochemistry
Least-squares regression methods are mathematically powerful, conceptually and computationally simple, and widely used in many fields. However, none of the commonly-used flavors of least-squares regression, such as York regression or Generalized Least Squares (GLS), take into account the full set of covariances between all observed (x,y) values. Here we describe the Omnivariant Generalized Least [...]