EISPAC

Description

Background & rationale

A number of stressors, marked in particular by climate-induced changes to ice regimes in the Arctic, are acting collectively on the distribution of organisms (Johansen et al. 2013), and structure and functioning of Arctic food webs (Grebmeier et al. 2006; Lee et al., 2013). The behaviour of long-lived contaminants with changing ice-regimes and exposure of ice-associated organisms during ice melt are unknown but likely contributes to contaminant residues in the foodweb and impacts Arctic marine ecosystem functioning.

There is an array of modern chemicals of growing concern present in the Arctic marine cryosphere (Cai et al., 2012), which now affect Arctic wildlife (Tartu et al., 2014). The risks they pose to organisms at the base of the marine food web are unclear, but accumulation processes in ice appear significant. The subsequent release during brine rejection from young ice and seasonal melt will affect exposure of biota.

Changing exposure to chemical contaminants due to climate induced perturbations in animal behaviour is an issue which is already affecting higher trophic level organisms like polar bears (Ursus maritimus) (McKinney et al., 2009). The key challenge is to understand the transfer and impact of contaminants at interfaces of major compartments (atmosphere, ice and ocean waters) and link periods of potentially high exposure (e.g. melt events associated with a ‘warmer’ Arctic) with the timing of biological events such as planktonic blooms and geochemical availability of nutrients in melting first year sea ice.

Clearly, the role of contaminants such as persistent chemicals and micro-plastics as co-stressors alongside changing ice regimes in the Arctic is an important area to understand, as examining the exposure and impact of these contaminants provides the necessary evidence for legislation and, importantly, raises public awareness. This is particularly pertinent in a changing Arctic, where altered physical processes may serve to ‘concentrate’ pollutants or change their dynamics (e.g. ice melt release), with unknown consequences on key species, habitats and ecosystem services.

Aim

The purpose of EISPAC is to evaluate whether ice-associated contaminants serve as stressors on ice habitat functioning in relation to cryosphere dynamics and in comparison to the behaviour of key nutrients. In essence, EISPAC will determine the magnitude and timing of exposure of contaminants to sentinel, ice-associated organisms and their effect on the lower marine foodweb relative to the timing and availability of key nutrients such as bioavailable forms of N and P.

Programme of work – key work packages (WP)

WP 1: Contaminants in the Arctic: entry and fate in the sea ice system of the marginal ice zone (MIZ)

This is a field and ship-based work package, with the aim of acquiring contaminant concentration datasets in the field, including for air, seawater, ice-rafted snowpack, bulk ice, ice brine and meltwater ponds as well as an array of ice-associated biota representing several trophic levels.

WP2: Mechanistic fate and behaviour studies of contaminants in an experimental sea ice facility

The aim of WP2 is to develop a chemical ice fate model based on controlled experiments examining chemical uptake, accumulation and release in freeze/thaw ice experiments. A mechanistic understanding of contaminant behaviour in sea ice will be achieved through ice-growth and melt experiments conducted using the Roland von Glasow Air-Sea-Ice Chamber (RvG-ASIC)

WP3: Nutrient input and biogeochemistry in the Arctic marine cryosphere

The aim of WP3 is to determine the entry of key nutrients to the ice-system and to investigate the biogeochemistry of dissolved organic and inorganic N (DON/DIN) particularly during ice melt and in coastal regions, and coupling this to the turnover of N in the surface layer of the Arctic Ocean.

WP4 Understanding the impact of multiple stressors and the repercussion for ecosystem services

The aim of WP-4 is to synthesise results from work packages 1-3, providing an initial evaluation of impacts on the pelagic ecosystem based on observed changes in the cryosphere and interactions between nutrients and contaminants.

References

Cai, M., Zhao, Z.,  Yin, Z., Ahrens, L. ; Huang, P., Cai, M., Yang, H., He, J., Sturm, R.,  Ebinghaus, R., Xie, Z. Occurrence of perfluoroalkyl compounds in surface waters from the North Pacific to the Arctic Ocean. Environmental Science & Technology 2012, 46, 661-668.

Grebmeier, J.M., Overland, J.E., Moore, S.E., Farley, E.V., Carmack, E.C., Cooper, L.W., Frey, K.E., Helle, J.H., McLaughlin, F.A., McNutt, S.L. A major ecosystem shift in the northern Bering Sea Science 2006, 311, 1461–1464.

Johansen, G.O., Johannesen, E., Michalsen, E., Aglen, A., Fotland, Å. Seasonal variation in geographic distribution of NEA cod – survey coverage in a warmer Barents Sea. Marine Biology Research 2013, 9, 908–919.

Lee, S. H., Yun, M.S., Kim, B.K., Joo, H.T., Kang, S-H., Kang, C.K, Whitledge, T. Contribution of small phytoplankton to total primary production in the Chukchi Sea. Continental Shelf Research 2013, 68, 43-50.

McKinney, M. A., Peacock, E., Letcher, R.J. Sea ice-associated diet change increases the levels of chlorinated and brominated contaminants in polar bears. Environ. Sci & Technol. 2009, 43, 4334-4339.

Tartu, S., Gabrielsen, G. W., Blevin, P., Ellis, H., Bustnes, J-O., Herzke, D., Chastel, O. Endocrine and fitness correlates of long-chain perfluorinated carboxylates exposure in Arctic breeding Black-Legged Kittiwakes Environmental Science & Technology 2014, 48, 13504-13510.