—Environmental contaminants are a global problem, and their presence in the Arctic reflects the way in which the Arctic interacts with the rest of the world. Most contaminants are transported to the North on air and ocean currents from more southerly agricultural and industrial sources. Upon reaching the Arctic environment, many persistent contaminants bioaccumulate and biomagnify in the food w...

We implemented a tagged tracer method of black carbon (BC) into a global chemistry transport model, GEOSChem, examined the pathways and efficiency of long-range transport from a variety of anthropogenic and biomass burning emission sources to the Arctic, and quantified the source contributions of individual emissions. Firstly, we evaluated the simulated BC by comparing it with observations at t...

Small rodents with multi-annual population cycles strongly influence the dynamics of food webs, and in particular predator-prey interactions, across most of the tundra biome. Rodents are however absent from some arctic islands, and studies on performance of arctic predators under such circumstances may be very instructive since rodent cycles have been predicted to collapse in a warming Arctic. ...

Amazon, 21, 24, 378–379 overbank, crevasses processes, 25 physical and biogeochemical processes, 92 plume dispersals, 55 sediment accumulation rates, 91 subaqueous delta clinoform system, 91–96 tidal-regime changes, sediment dynamics model, 92–94 Arctic Ocean, riverine organic and inorganic carbon fluxes, processing, fate acids to aldehydes ratios, 534–535 aragonite undersaturation, 542–543 Arc...

to 100 DU or even less. Such severe depletion was not observed in the Arctic. Judged by these criteria, there was no Arctic ozone hole in 2011 — only the most extreme episode of ozone loss seen in the Arctic so far. However, the evolution of HNO3, HCl and ClO species was strikingly Antarctic-like and different from what has been observed in other Arctic winters. On the basis of these considerat...

Clouds and their radiative impacts are of primary importance to the Arctic climate and, therefore, global climate. Clouds dominate the radiation balance within the cold, dry Arctic atmosphere, and cloudradiation feedbacks are closely linked with the snow/ice-albedo feedback. Despite the importance of clouds in the Arctic, our current understanding of these clouds remains limited. Global climate...

The two-branched inflow of warm and saline Atlantic Water to the Arctic is the major contributor of oceanic heat to the Arctic climate system. However, while the Atlantic Water entering the Arctic through the Fram Strait retains a large part of its heat as it flows along the Arctic continental slope, the branch flowing through the shallow Barents Sea releases a substantial amount of heat to the...

In light of ocean warming and loss of Arctic sea ice, harvested marine fishes of boreal origin (and their fisheries) move poleward into yet unexploited parts of the Arctic seas. Industrial fisheries, already in place on many Arctic shelves, will radically affect the local fish species as they turn up as unprecedented bycatch. Arctic marine fishes are indispensable to ecosystem structuring and f...

Marine birds are sensitive indicators of the condition of marine ecosystems in the Arctic, partly because they feed at the top of the arctic food chain. The Northern Ecosystem Initiative (NEI) recently supported four separate studies that investigated aspects of Arctic marine bird science which simultaneously addressed goals of the NEI to better understand northern ecosystems and their response...

Black carbon (BC) aerosols from incomplete combustion of biomass and fossil fuel contribute to Arctic climate warming. Models-seeking to advise mitigation policy-are challenged in reproducing observations of seasonally varying BC concentrations in the Arctic air. Here we compare year-round observations of BC and its δ(13)C/Δ(14)C-diagnosed sources in Arctic Scandinavia, with tailored simulation...