Publications associées à Rapid grain boundary diffusion in foraminifera tests biases paleotemperature records

Diagenetic isotope exchange in biocalcites for paleoclimate reconstruction

The oxygen isotope compositions of fossil biocalcites, such as foraminifera, bivalves, brachiopods, and belemnites have allowed for reconstructions of sea surface and deep ocean temperatures throughout the Phanerozoic and constitute the most important reco ...

EPFL2024

The isotopic signature of U(V) during bacterial reduction

Marinella Mazzanti, Rizlan Bernier-Latmani, Margaux Camille Andréa Molinas, Radmila Faizova, Ashley Richards Brown

The two-step electron transfer during bacterial reduction of UVI to UIV is typically accompanied by mass-independent fractionation of the 238U and 235U isotopes, whereby the heavy isotope accumulates in the reduced product. However, the role of the UV inte ...

2024

Organic matters, but inorganic matters too: column examination of elevated mercury sorption on low organic matter aquifer material using concentrations and stable isotope ratios

Lorenz Schwab

Sorption of mercury (Hg) in soils is suggested to be predominantly associated with organic matter (OM). However, there is a growing collection of research that suggests that clay minerals and oxides are also important solid phases for the sorption of solu ...

2024

Multi-year time series of daily solute and isotope measurements from three Swiss pre-Alpine catchments

Jana Freiin von Freyberg

Time series analyses of solute concentrations in streamwater and precipitation are powerful tools for unraveling the interplay of hydrological and biogeochemical processes at the catchment scale. While such datasets are available for many sites around the ...

Nature Portfolio2024

Technical note: Two-component electrical-conductivity-based hydrograph separation employing an exponential mixing model (EXPECT) provides reliable high-temporal-resolution young water fraction estimates in three small Swiss catchments

Jana Freiin von Freyberg, Davide Canone

The young water fraction represents the portion of water molecules in a stream that have entered the catchment relatively recently, typically within 2-3 months. It can be reliably estimated in spatially heterogeneous and nonstationary catchments from the a ...

Copernicus Gesellschaft Mbh2024

High power electrostatic beam splitter for a proton beamline

Mike Seidel, Hua Zhang

The High Intensity Proton Accelerator facility (HIPA) delivers a 590 MeV cw (50.6 MHz) proton beam with up to 1.4 MW beam power (2.4 mA) to spallation and meson production targets serving particle physics experiments and material research. The main acceler ...

2024

Gene expression of Pocillopora damicornis coral larvae in response to acidification and ocean warming

Nils Rädecker, Hui Huang

Objectives The endosymbiosis with Symbiodiniaceae is key to the ecological success of reef-building corals. However, climate change is threatening to destabilize this symbiosis on a global scale. Most studies looking into the response of corals to heat str ...

BMC2024

Assessing sublimation during snow transport and sublimation effects on the isotopic composition of water vapor

Armin Sigmund

Sublimation influences the water storage in snow covers and glaciers, which is important for water use and projections of the sea level rise. Yet, it is challenging to quantify sublimation for large areas or in conditions of snow transport. In-situ measure ...

EPFL2023

Mercury Isotope Fractionation during Dark Abiotic Reduction of Hg(II) by Dissolved, Surface-Bound, and Structural Fe(II)

Lorenz Schwab

Stable mercury (Hg) isotope ratios are an emerging tracer for biogeochemical transformations in environmental systems, but their application requires knowledge of isotopic enrichment factors for individual processes. We investigated Hg isotope fractionatio ...

Amer Chemical Soc2023

A Case Study on Drivers of the Isotopic Composition of Water Vapor at the Coast of East Antarctica

Michael Lehning, Armin Sigmund, Riqo Chaar

Stable water isotopes (SWIs) contain valuable information on the past climate and phase changes in the hydrologic cycle. Recently, vapor measurements in the polar regions have provided new insights into the effects of snow-related and atmospheric processes ...

AMER GEOPHYSICAL UNION2023