Future changes in Arctic sea-ice biogeochemistry and associated ecosystems


Following the Arctic Sea-Ice Change foresight workshop held in DAVOS in June 2018, BEPSII community commits itself to write a position analysis paper : Future changes in Arctic sea-ice biogeochemistry and associated ecosystems

Motivation: Arctic sea ice is rapidly retreating at a pace dictated by cumulative CO2 emissions (Notz and Stroeve, 2016). In addition, the properties of sea ice are changing. Older ice that has survived multiple summers is rapidly disappearing; most sea ice in the Arctic is now first-year ice (Comiso, 2012; Meier, 2014) that grows in the autumn and winter but melts completely during the spring and summer. How this shift in sea-ice conditions may affect the climatic, biogeochemical and biological processes in the Arctic, and beyond, urgently needs to be evaluated.

Sea-ice variables:

  • physico-chemistry (e.g. nutrients, light, water column stratification).
  • biota (from primary production to fish).
  • climate-active gases (CO2 including ocean acidification, O2, CH4 DMS, halogens).

Scenarios:

In the workshop, near-future changes (i.e. 2050 horizon) in three Arctic bioregions were discussed, following two scenarios:

  • Changes in ice structure: thinner, warmer, younger, more permeable, more mobile, more deformed sea ice, in association with increasing rain and less snow accumulation;
  • Changes in ice coverage: sea-ice volume, area and seasonality.

Bioregions:

1. Basin (blue shading), 2. Shelf (pink shading), 3. Outflow Shelf (green shading)


Product:

  • An opinion paper is currently in writing by the BEPSII sea-ice biogeochemistry community, for submission in march 2019 as an invited perspective paper in Nature Climate Change.
  • The paper will provide our best estimate of expected changes in climate-relevant BGC variables in different bioregions.

References

Comiso, J. C. (2012) Journal of Climate 25(4): 1176–1193.

Notz D. & Stroeve J. (2016) Science 354 (6313): 747-750.

Meier W.N. et al (2014). Reviews of Geophysics 51: 185–217

ASIC foresight workshop in Davos in June 2018. In total, 40 people representing 14 countries attended the ASIC workshop.

This work is supported by the Euromarine Network.