Bromide oxidation by bromate in a frozen solution and reactive bromine species production.

A sudden increase in tropospheric reactive bromine species (such as BrO radical) concentration has been observed in the Arctic springtime (bromine explosion). The reactive bromine radicals originate from the Br oxidation; however, the role of ice chemistry in bromine activation, especially freezing-induced Br oxidation for Br production, is not significantly considered yet. Notably, the freezing phenomenon is prevalent in polar region.

Photodegradation of bisphenol A and identification of photoproducts in artificial snow under UVA radiation.

Bisphenol A (BPA) is an organic micropollutant detected in various environments, from urban to remote areas, including Arctic snow. As a known endocrine disruptor, it is essential to investigate its environmental fate and potential impact on ecosystems. Previous studies have explored BPA photodegradation and its transformation products in different aqueous environments (freshwater, seawater, and ice), by using photosensitizers to trigger specific reactions.

Acidity-driven gas-particle partitioning of nitrate regulates its transport to Arctic through the industrial era.

Anthropogenic NO emissions have altered the biogeochemical nitrogen cycle since the Industrial Revolution, yet Arctic ice core nitrate (NO) records are inconsistent with post-1970s NO emission reductions. Here we show a NO deposition history covering 1800-2020 using an ice core from the southeastern Greenland dome with high snow accumulation. The ice core NO concentrations are particularly disconnected from NO source regions during the peak pollution period and post-1990s.

Are ingredients of personal care products likely to undergo long-range transport to remote regions?

Personal care products (PCPs) contain contaminants of emerging concern. Despite increasing reports of their presence in polar regions, the behavior of PCP ingredients under cold environmental conditions remains poorly understood. Snow collected around Villum Research Station at Station Nord, Greenland, between December 2018 and June 2019 was extracted in a stainless steel clean-room and analyzed for seven fragrance materials, four organic UV-filters and an antioxidant using gas chromatography-tandem mass spectrometry.

Photoreduction of mercuric bromides in polar ice.

In the polar regions, which are vulnerable receptors of mercury pollution, atmospheric mercury depletion events (AMDEs) efficiently convert elemental mercury (Hg(0)) into oxidized mercury (Hg(II)) via bromine oxidation. Hg(II) subsequently deposits onto snow and sea ice. While field observations have shown that a large percentage of deposited mercury is re-emitted from the ice to the atmosphere by a photoinduced process, the fundamental photochemistry that drives the re-emission process remains unknown.

Calibration of Arctic ice core bromine enrichment records for past sea ice reconstructions.

Bromine in ice cores has been proposed as a qualitative sea ice proxy to produce sea ice reconstructions for the polar regions. Here we report the first statistical validation of this proxy with satellite sea ice observations by combining bromine enrichment (with respect to seawater, Br) records from three Greenlandic ice cores (SIGMA-A, NU and RECAP) with satellite sea ice imagery, over three decades. We find that during the 1984-2016 satellite-era, ice core Br values are significantly correlated with first-year sea ice formed in the Baffin Bay and Labrador Sea supporting that the gas-phase bromine enrichment processes, preferentially occurring over the sea ice surface, are the main driver for the Br signal in ice cores.

Photodegradation of bisphenol A in water and ice: identification of products using three photosensitizers.

Bisphenol A (BPA) is a widespread organic micro-pollutant, found in most environments, including alpine and Arctic regions, and several matrices such as waters and aerosols. Polar regions are characterized by periods of intense irradiation with no sunset due to the continuous sunlight, while alpine areas, despite following the day-night cycle of mid-latitudes, also undergo strong irradiation. For such conditions, it is possible that a fraction of the BPA present in snow may degrade through direct photolysis, producing other unknown species with different environmental mobility and possible ecotoxic effects.

Characteristics and quantification of small microplastics (<100 µm) in seasonal svalbard snow on glaciers and lands.

Small microplastics (SMPs < 100 µm) can easily be transported over long distances far from their sources through the atmospheric pathways and reach even remote regions, including the Arctic. However, these sizes of MPs are mostly overlooked due to different analytical challenges; besides, their pathways through atmospheric depositions, such as snow depositions, are mostly unknown. The spatial variability in bulk snow samples was investigated for the first time in distinct sites (e.

Chemicals of Emerging Arctic Concern in north-western Spitsbergen snow: Distribution and sources.

Personal care products contain chemicals that are considered of emerging concern in the Arctic. In this study, a selected group of personal care products was investigated in the snowpack on north-western Spitsbergen. We report a preliminary study on the spatial and seasonal distribution of 13 ingredients commonly found in personal care products, including fragrance materials, UV filters, BHT and BPA.

The seasonal change of PAHs in Svalbard surface snow.

The Arctic region is threatened by contamination deriving from both long-range pollution and local human activities. Polycyclic Aromatic Hydrocarbons (PAHs) are environmental tracers of emission, transport and deposition processes. A first campaign has been conducted at Ny-Ålesund, Svalbard, from October 2018 to May 2019, monitoring weekly concentrations of PAHs in Arctic surface snow.

Long-range transport and deposition on the Arctic snowpack of nuclear contaminated particulate matter.

The primary environmental concern related to nuclear power is the production of radioactive waste hazardous to humans and the environment. The main scientific and technological problems to address this are related to the storage and disposal of the nuclear waste and monitoring the dispersion of radioactive species into the environment. In this work, we determined an anomalously high C activity, well above the modern natural background, on surface and seasonal snow sampled in early May 2019 on glaciers in the Hornsund fjord area (Svalbard).

Sea ice fluctuations in the Baffin Bay and the Labrador Sea during glacial abrupt climate changes.

Sea ice decline in the North Atlantic and Nordic Seas has been proposed to contribute to the repeated abrupt atmospheric warmings recorded in Greenland ice cores during the last glacial period, known as Dansgaard-Oeschger (D-O) events. However, the understanding of how sea ice changes were coupled with abrupt climate changes during D-O events has remained incomplete due to a lack of suitable high-resolution sea ice proxy records from northwestern North Atlantic regions. Here, we present a subdecadal-scale bromine enrichment (Br) record from the NEEM ice core (Northwest Greenland) and sediment core biomarker records to reconstruct the variability of seasonal sea ice in the Baffin Bay and Labrador Sea over a suite of D-O events between 34 and 42 ka.

Climate changes modulated the history of Arctic iodine during the Last Glacial Cycle.

Iodine has a significant impact on promoting the formation of new ultrafine aerosol particles and accelerating tropospheric ozone loss, thereby affecting radiative forcing and climate. Therefore, understanding the long-term natural evolution of iodine, and its coupling with climate variability, is key to adequately assess its effect on climate on centennial to millennial timescales. Here, using two Greenland ice cores (NEEM and RECAP), we report the Arctic iodine variability during the last 127,000 years.

Antarctic ozone hole modifies iodine geochemistry on the Antarctic Plateau.

Polar stratospheric ozone has decreased since the 1970s due to anthropogenic emissions of chlorofluorocarbons and halons, resulting in the formation of an ozone hole over Antarctica. The effects of the ozone hole and the associated increase in incoming UV radiation on terrestrial and marine ecosystems are well established; however, the impact on geochemical cycles of ice photoactive elements, such as iodine, remains mostly unexplored. Here, we present the first iodine record from the inner Antarctic Plateau (Dome C) that covers approximately the last 212 years (1800-2012 CE).

Year-round measurements of size-segregated low molecular weight organic acids in Arctic aerosol.

Organic acids in aerosols Earth's atmosphere are ubiquitous and they have been extensively studied across urban, rural and polar environments. However, little is known about their properties, transport, source and seasonal variations in the Svalbard Archipelago. Here, we present the annual trend of organic acids in the aerosol collected at Ny-Ålesund and consider their size-distributions to infer their possible sources and relative contributions.

First discrete iron(II) records from Dome C (Antarctica) and the Holtedahlfonna glacier (Svalbard).

Fe(II) is more soluble and bioavailable than Fe(III) species, therefore the investigation of their relative abundance and redox processes is relevant to better assess the supply of bioavailable iron to the ocean and its impact on marine productivity. In this context, we present a discrete chemiluminescence-based method for the determination of Fe(II) in firn matrices. The method was applied on discrete samples from a snow pit collected at Dome C (DC, Antarctica) and on a shallow firn core from the Holtedahlfonna glacier (HDF, Svalbard), providing the first Fe(II) record from both Antarctica and Svalbard.

Rapid reductions and millennial-scale variability in Nordic Seas sea ice cover during abrupt glacial climate changes.

Constraining the past sea ice variability in the Nordic Seas is critical for a comprehensive understanding of the abrupt Dansgaard-Oeschger (D-O) climate changes during the last glacial. Here we present unprecedentedly detailed sea ice proxy evidence from two Norwegian Sea sediment cores and an East Greenland ice core to resolve and constrain sea ice variations during four D-O events between 32 and 41 ka. Our independent sea ice records consistently reveal a millennial-scale variability and threshold response between an extensive seasonal sea ice cover in the Nordic Seas during cold stadials and reduced seasonal sea ice conditions during warmer interstadials.

Source, timing and dynamics of ionic species mobility in the Svalbard annual snowpack.

Nearly all ice core archives from the Arctic and middle latitudes (such as the Alps), apart from some very high elevation sites in Greenland and the North Pacific, are strongly influenced by melting processes. The increases in the average Arctic temperature has enhanced surface snow melting even of higher elevation ice caps, especially on the Svalbard Archipelago. The increase of the frequency and altitude of winter "rain on snow" events as well as the increase of the length of the melting season have had a direct impact on the chemical composition of the seasonal and permanent snow layers due to different migration processes of water-soluble species, such as inorganic ions.

Interannual variability of sugars in Arctic aerosol: Biomass burning and biogenic inputs.

The concentrations and particle-size distribution of sugars in Arctic aerosol samples were studied to investigate their potential sources and transport. Sugars are constituents of the water-soluble organic compounds (WSOC) fraction in aerosol particles where some saccharides are used as tracers of Primary Biological Aerosol Particles (PBAPs). Monosaccharides (arabinose, fructose, galactose, glucose, mannose, ribose, xylose), disaccharides (sucrose, lactose, maltose, lactulose), alcohol-sugars (erythritol, mannitol, ribitol, sorbitol, xylitol, maltitol, galactitol) and anhydrosugars (levoglucosan, mannosan and galactosan) were quantified in aerosol samples collected during three different sampling campaigns (spring and summer 2013, spring 2014 and 2015).

Fe in ice cores as a new potential proxy to detect past volcanic eruptions.

Volcanic eruptions are widely used in ice core science to date or synchronize ice cores. Volcanoes emit large amounts of SO that is subsequently converted in the atmosphere into sulfuric acid/sulphate. Its discrete and continuous quantification is currently used to determine the ice layers impacted by volcanic emissions, but available high-resolution sulphate quantification methods in ice core (Continuous Flow Analysis (CFA)) struggle with insufficient sensitivity.

Free and combined L- and D-amino acids in Arctic aerosol.

Aerosol samples were collected with a high-volume cascade impactor with a 10 day sampling frequency at the Gruvebadet observatory, close to Ny-Ålesund (Svalbard Islands). A total of 42 filters were analyzed for free and combined amino acids, as they are key components of bio-aerosol. This article provides the first investigation of free and combined L- and d-amino acids in Arctic atmospheric particulate matter.

Fragrances and PAHs in snow and seawater of Ny-Ålesund (Svalbard): Local and long-range contamination.

Polar regions are fragile ecosystems threatened by both long-range pollution and local human contamination. In this context, the environmental distribution of the Personal Care Products (PCPs) represent a major knowledge gap. Following preliminary Antarctic studies, Fragrance Materials (FMs) were analyzed in the seawater and snow collected in the area of Ny-Ålesund, Svalbard, to investigate local and long-range contamination.