Sea ice is a key component of the Arctic climate and ocean systems. While satellite observations indicate a dramatic decrease of the areal extent of sea ice cover in the Arctic Ocean and a thinning of multi-year ice over the last three decades, predictive climate models underestimate the current rate of sea-ice decline. In addition, there is still a need to discriminate between natural and anthropogenic forcing of sea ice dynamics.
These two issues will be addressed through:
1.improving algorithms for the analysis of satellite data in order to better understand the evolution of the proportion of multi-year vs first-year ice, due to the large effect of this ratio on the ocean-atmosphere heat exchange and marine biological productivity, and to establish a consistent and reliable time series of the Arctic multiyear sea ice.
2.studying sea-ice time series that extend further back in time than instrumental/observation records, with the use of biogenic proxies (e.g. IP25, dinocysts).
The combined information on sea-ice variability and sea-ice processes on timescales ranging from years to millennia will be used to benchmark and improve the representation of sea-ice dynamics in climate models.