Preprints
Filtering by Subject: Physical Sciences and Mathematics
Reproducing the Mid-Piacenzian Warm Period Climate in the 2020s.
Published: 2023-10-17
Subjects: Physical Sciences and Mathematics
The current expectation of climatologists is that levels of atmospheric carbon dioxide (CO2) and other greenhouse gases, such as methane (CH4) and nitrous oxide (N2O), will correspond, in the 2020s, to an increase in mean annual global near-surface atmospheric temperature of less than 1.5°C above the pre-industrial Holocene norm (1750 baseline; atmospheric CO2 = 278 ppm). This paper will argue, [...]
Global ocean spatial suitability for macroalgae offshore cultivation and sinking
Published: 2023-10-17
Subjects: Physical Sciences and Mathematics
Macroalgae offshore cultivation and sinking is considered a potentially practical approach for ocean-based carbon dioxide removal. However, several considerations need to be resolved to assess the effectiveness and sustainability of this approach. Currently, several studies focus on the area required for climate-relevant carbon sequestration through macroalgae cultivation and sinking without [...]
Moving graphs: Predicting barchan dune migration rates from their shapes
Published: 2023-10-17
Subjects: Physical Sciences and Mathematics
In this study, geometric perspectives on sand dune formation and motion are summarized, introduced, and combined to predict time-averaged velocities (migration rates) of barchan dunes directly from their shapes. First, it is proposed that smaller sediment accumulations outpace larger ones due to differences in surface-to-volume ratio. This ratio is defined by a bedform’s wavelength and its [...]
Short-term magma-carbonate interaction: A modelling perspective
Published: 2023-10-17
Subjects: Physical Sciences and Mathematics
The short-term, syn-eruptive interaction of magma with crustal carbonates can largely affect the eruptive style and drive even low-viscosity magmas toward large explosive eruptions. Only a few studies focus on the short-term interaction and the physical processes behind the experimental observations are still poorly understood. In this work, we study for the first time the short-term [...]
What is coastal subsidence?
Published: 2023-10-13
Subjects: Physical Sciences and Mathematics
While major technological advances have made measurements of coastal subsidence more sophisticated, these advances have not always been matched by a thorough examination of what is actually being measured. Here we draw attention to the widespread miscommunication about key concepts in the coastal subsidence literature, much of which revolving around the interplay between sediment accretion, [...]
Future (2015-2100) Antarctic-wide ice-shelf firn air depletion from a statistical firn emulator
Published: 2023-10-13
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
Antarctic firn is critical for ice-shelf stability because it stores meltwater that would otherwise pond on the surface. Ponded meltwater increases the risk of hydrofracture, and subsequent potential ice-shelf collapse. Here, we use output from a firn model to build a computationally simpler emulator that uses a random forest to predict ice-shelf firn air content (FAC) based on climate [...]
Limited reversal of regional climate signals in overshoot scenarios
Published: 2023-10-12
Subjects: Physical Sciences and Mathematics
Without stringent reductions in emission of greenhouse gases in the coming years, an exceedance of the 1.5C temperature limit would become increasingly likely. This has given rise to so-called temperature overshoot scenarios, in which the global mean surface air temperature increase above pre-industrial levels exceeds a certain limit, i.e. 1.5C, before bringing temperatures back below that level. [...]
Microbial catabolic and anabolic utilization of hydrocarbons in deep subseafloor sediments of Guaymas Basin
Published: 2023-10-11
Subjects: Physical Sciences and Mathematics
Guaymas Basin, located off the Gulf of California, is a hydrothermally active marginal basin. Due to steep geothermal gradients and localized heating by sill intrusions, microbial substrates like short-chain fatty acids and hydrocarbons are abiotically produced from sedimentary organic matter at comparatively shallow depths. However, the potential of hydrocarbons as microbial substrates for both [...]
The Heavy Mineral Map of Australia Project: A Novel, Rapid, Automated Quantitative Mineralogy Workflow
Published: 2023-10-10
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics
The Heavy Mineral Map of Australia (HMMA) is the world’s first project aiming to define a continental heavy mineral baseline. It utilises a novel sample processing workflow and automated mineralogy techniques to rapidly generate and analyse mineralogical data from 1315 archived samples of catchment outlet sediments collected from 1186 catchments across the Australian continent. Heavy [...]
Climate- and Weather-Driven Solid-Earth Deformation and Seismicity
Published: 2023-10-10
Subjects: Physical Sciences and Mathematics
There is long-standing interest in the interactions between atmospheric and hydrological processes and solid Earth deformation, including the occurrence of earthquakes. Here, we review evidence for the effects of climatic processes and weather on deformation and seismicity in the lithosphere over a wide range of time scales, ranging from load cycles associated with the ice ages to the effects of [...]
Field Report No. 3 - Tabor Tree Project Summary Report 2021
Published: 2023-10-10
Subjects: Adult and Continuing Education, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Environmental Studies, Outdoor Education, Physical Sciences and Mathematics
“The Friends of Mt. Tabor Park (FMTP) was organized as a non-profit group* in 2000. Our pur- pose is to improve and help maintain Mt. Tabor Park for the benefit of individuals, organizations and the Park Bureau; to identify and help solve problems; and to participate in park planning projects.”(FMTP) During the winter of 2021 with covid closures of the Visitor Center, Tree Medicine hikes were [...]
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 [...]
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 ‘hidden story’ in simulating reflected radiance by wind-roughened sea surface: Mobley’s 1999 paper on simulation of Rrs measurements via the above-surface approach
Published: 2023-10-07
Subjects: Physical Sciences and Mathematics
Remote sensing reflectance (Rrs, in sr-1) is defined as the ratio of water-leaving radiance (Lw) to downwelling irradiance just above the water surface (Es). To measure Rrs, the above-water approach (AWA) is a widely adopted scheme in the past decades. In addition to the measurement of Es, AWA also involves measurements of upwelling radiance above the surface (Lt) and downwelling sky radiance [...]