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.
