Filtering by Subject: Physical Sciences and Mathematics
Published: 2023-11-30
Subjects: Physical Sciences and Mathematics
Moving down a hillslope from ridge to valley, soil develops and becomes increasingly weathered. Downslope variation in clay content, organic matter, and porosity should produce concomitant changes in soil strength that influence slope stability and erosion. This has yet to be demonstrated, however, because in-situ measurements of soil rheology are challenging and rare. Here we employ a robotic [...]
Published: 2023-11-29
Subjects: Physical Sciences and Mathematics
On October 8, 2023, at 21:40 UTC (6:40 on October 9 local time), a tsunami warning was declared for the Izu Islands and southwest Japan. This tsunami was initially considered to be associated with the M4.9 earthquake at 20:25 UTC (5:25 JST). However, we know events of this magnitude are far too small to generate observed tsunamis from coseismic deformation alone. In this study, we analyzed the [...]
Published: 2023-11-28
Subjects: Physical Sciences and Mathematics
All pathways which limit global temperature rise to <2oC above pre-industrial temperatures now require carbon dioxide removal (CDR) in addition to rapid greenhouse gas emissions reductions. Novel and durable CDR strategies need to rapidly scale over the next few decades in order to reach Paris Agreement Targets. Terrestrial enhanced weathering (EW) involves the acceleration of natural weathering [...]
Published: 2023-11-28
Subjects: Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Planetary Sciences
ICESat-2’s Advanced Topographic Laser Altimeter System (ATLAS) has emerged as useful tool for calculating attenuation signals in natural surface waters, thus improving our understanding of particulates from open-ocean plankton to nearshore suspended terrigenous sediments. While several studies have employed methods based on Beer’s Law to derive attenuation coefficients (including through a [...]
Published: 2023-11-23
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Volcanology
Compositions of plagioclase-melt pairs are commonly used to constrain temperatures (T), water contents (H2O) and pressures (P) of pre-eruptive magma storage. However, previous plagioclase-based thermometers, hygrometers, and barometers can have significant uncertainties, mainly resulting from the lack of error propagation of independently-constrained input variables (i.e., T/ H2O/P), leading to [...]
Published: 2023-11-23
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The transport of Warm Deep Water (WDW) onto the Weddell Sea continental shelf is associated with a heat flux and strongly contributes to the melting of Antarctic ice shelves. The small radius of deformation at high latitudes makes it difficult to accurately represent the eddy-driven component of onshore WDW transport in coarse-resolution ocean models so that a parameterization becomes necessary. [...]
Published: 2023-11-22
Subjects: Physical Sciences and Mathematics
Diurnal Warm Layers (DWLs) form near the surface of the ocean on days with strong solar radiation, weak to moderate winds, and small surface-wave effects. Here, we identify the key non-dimensional parameters for DWL evolution, and use idealized Large Eddy Simulations (LES) and second-moment turbulence modelling, both including the effects of Langmuir turbulence, to study the properties and [...]
Published: 2023-11-22
Subjects: Physical Sciences and Mathematics
A small Arctic floodplain-lake (Tendammen, Colesdalen valley) in Svalbard revealed a laminated sediment sequence with numerous 14C AMS age-depth reversals in its 800 year history. In order to test the hypothesis that the anomalous dates result from catchment erosion and the deposition of reworked sediment and macrofossils, we applied luminescence profiling and flood-sensitive biological proxies. [...]
Published: 2023-11-22
Subjects: Physical Sciences and Mathematics
Standardised indices are measurements of variables on a standardised scale. The standardised scale facilitates comparisons between different variables, and its probabilistic interpretation means the indices are effective for risk management and decision making. Standardised indices have become popular in weather and climate settings, for example within operational drought monitoring systems, [...]
Published: 2023-11-16
Subjects: Earth Sciences, Geophysics and Seismology, Glaciology, Physical Sciences and Mathematics
Understanding deformation and slip at ice streams, which are responsible for 90% of Antarctic ice loss, is vital for accurately modelling large-scale ice flow. Ice preferred crystal orientation fabric (COF) has a first-order effect on ice stream deformation. For the first time, we use shear-wave splitting (SWS) measurements of basal icequakes at Whillans Ice Stream (WIS), Antarctica, to determine [...]
Published: 2023-11-14
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
We reconstruct upsystem-to-downsystem grain-size variations in the sediment routing systems of the data-rich Middle Jurassic Brent Group of the northern North Sea, using published stratigraphic, thickness, palaeogeographic, provenance and age constraints combined with representative core and wireline-log data. Facies associations provide a textural proxy for gravel, sand and mud grain-size [...]
Published: 2023-11-14
Subjects: Earth Sciences, Physical Sciences and Mathematics, Volcanology
The chemical and isotopic composition of the gases emitted by subduction zone volcanoes can provide insights into the origin of magmatic volatiles. In volcanic arcs, magmatic volatiles and therefore emitted gases can be supplied from the mantle, the subducting slab, or the rocks of the arc crust. Determining the relative contributions of these distinct sources is important for understanding the [...]
Published: 2023-11-11
Subjects: Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Although the 2015 Paris Agreement climate targets seem certain to be missed, only a few experts are questioning the adequacy of the current approach to limiting climate change and suggesting that additional approaches are needed to avoid unacceptable catastrophes. This article posits that selective science communication and unrealistically optimistic assumptions are obscuring the reality that [...]
Published: 2023-11-11
Subjects: Physical Sciences and Mathematics
Carbonate minerals are globally distributed on the modern and ancient Earth and are abundant in terrestrial and marine depositional environments. Fluid inclusions hosted by calcite retain primary signatures of the source fluid geochemistry at the time of mineral formation (i.e., pCO2) and can be used to reconstruct paleoenvironments. Confocal laser Raman spectroscopy provides a quick, [...]
Published: 2023-11-09
Subjects: Physical Sciences and Mathematics
In high northern latitudes, the Middle to Late Holocene was a time of orbitally-induced atmospheric cooling. This led to increased sea-ice production in the Arctic Ocean and its export southward, a decrease in sea surface temperatures (SST), and glacier advances at least since 5-4 ka BP. However, the response of the ocean-climate system to decreasing insolation was not uniform. Our research shows [...]