Identifying the provenance and quantifying the contribution of dust sources in EPICA Dronning Maud Land ice core (Antarctica) over the last deglaciation (7-27 kyr BP): A high-resolution, quantitative record from a new Rare Earth Element mixing model.

Antarctic ice cores have revealed the interplay between dust and climate in the Southern Hemisphere. Yet, so far, no continuous record of dust provenance has been established through the last deglaciation. Here, using a new database of 207 Rare Earth Element (REE) patterns measured in dust and sediments/soils from well-known potential source areas (PSA) of the Southern Hemisphere, we developed a statistical model combining those inputs to provide the best fit to the REE patterns measured in EPICA Dronning Maud Land (EDML) ice core (E.

Nanoplastics measurements in Northern and Southern polar ice.

It has been established that various anthropogenic contaminants have already reached all the world's pristine locations, including the polar regions. While some of those contaminants, such as lead and soot, are decreasing in the environment, thanks to international regulations, other novel contaminants emerge. Plastic pollution has been shown as a durable novel pollutant, and, since recently, smaller and smaller plastics particles have been identified in various environments (air, water and soil).

A multimillion-year-old record of Greenland vegetation and glacial history preserved in sediment beneath 1.4 km of ice at Camp Century.

Understanding the history of the Greenland Ice Sheet (GrIS) is critical for determining its sensitivity to warming and contribution to sea level; however, that history is poorly known before the last interglacial. Most knowledge comes from interpretation of marine sediment, an indirect record of past ice-sheet extent and behavior. Subglacial sediment and rock, retrieved at the base of ice cores, provide terrestrial evidence for GrIS behavior during the Pleistocene.

Variability in sulfur isotope composition suggests unique dimethylsulfoniopropionate cycling and microalgae metabolism in Antarctic sea ice.

Sea ice microbial communities produce large amounts of the sulfur metabolite dimethylsulfoniopropionate (DMSP), a precursor of the climate cooling gas dimethylsulfide. Despite their importance to the polar sulfur cycle, drivers and metabolic pathways of sea ice DMSP are uncertain. Here we report the first measurements of sea ice DMSP sulfur isotopic composition (S/S ratio, δS).

The first known virus isolates from Antarctic sea ice have complex infection patterns.

Viruses are recognized as important actors in ocean ecology and biogeochemical cycles, but many details are not yet understood. We participated in a winter expedition to the Weddell Sea, Antarctica, to isolate viruses and to measure virus-like particle abundance (flow cytometry) in sea ice. We isolated 59 bacterial strains and the first four Antarctic sea-ice viruses known (PANV1, PANV2, OANV1 and OANV2), which grow in bacterial hosts belonging to the typical sea-ice genera Paraglaciecola and Octadecabacter.

An active bacterial community linked to high chl-a concentrations in Antarctic winter-pack ice and evidence for the development of an anaerobic sea-ice bacterial community.

Antarctic sea-ice bacterial community composition and dynamics in various developmental stages were investigated during the austral winter in 2013. Thick snow cover likely insulated the ice, leading to high (<4 μg l) chlorophyll-a (chl-a) concentrations and consequent bacterial production. Typical sea-ice bacterial genera, for example, Octadecabacter, Polaribacter and Glaciecola, often abundant in spring and summer during the sea-ice algal bloom, predominated in the communities.

Massive subsurface ice formed by refreezing of ice-shelf melt ponds.

Surface melt ponds form intermittently on several Antarctic ice shelves. Although implicated in ice-shelf break up, the consequences of such ponding for ice formation and ice-shelf structure have not been evaluated. Here we report the discovery of a massive subsurface ice layer, at least 16 km across, several kilometres long and tens of metres deep, located in an area of intense melting and intermittent ponding on Larsen C Ice Shelf, Antarctica.

High-accuracy determination of iron in seawater by isotope dilution multiple collector inductively coupled plasma mass spectrometry (ID-MC-ICP-MS) using nitrilotriacetic acid chelating resin for pre-concentration and matrix separation.

In the present paper we describe a robust and simple method to measure dissolved iron (DFe) concentrations in seawater down to <0.1 nmol L(-1) level, by isotope dilution multiple collector inductively coupled plasma mass spectrometry (ID-MC-ICP-MS) using a (54)Fe spike and measuring the (57)Fe/(54)Fe ratio. The method provides for a pre-concentration step (100:1) by micro-columns filled with the resin NTA Superflow of 50 mL seawater samples acidified to pH 1.

Precise measurement of Fe isotopes in marine samples by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS).

A novel analytical technique for isotopic analysis of dissolved and particulate iron (Fe) from various marine environments is presented in this paper. It combines coprecipitation of dissolved Fe (DFe) samples with Mg(OH)(2), and acid digestion of particulate Fe (PFe) samples with double pass chromatographic separation. Isotopic data were obtained using a Nu Plasma MC-ICP-MS in dry plasma mode, applying a combination of standard-sample bracketing and external normalization by Cu doping.