Expanding influence of Atlantic and Pacific ocean heat transport on
Arctic winter sea ice variability
- Jakob Dörr,
- Marius Årthun,
- Tor Eldevik,
- Anne Britt Sandø
Marius Årthun
Geophysical Institute, University of Bergen
Author ProfileAbstract
The general retreat of Arctic sea ice is overlaid by large year-to-year
variability. In winter, sea ice loss and variability are currently most
pronounced in the Barents Sea, primarily due to variable ocean heat
transport from the Atlantic. As the loss of winter Arctic sea ice is
expected to continue and the sea ice edge retreats deeper into the
Arctic Ocean, other regions will experience increased sea-ice
variability until essentially ice-free. However, it remains to be
established to what extent future winter sea ice loss beyond the Barents
Sea is facilitated by ocean heat transport. To answer this question, we
analyze and contrast the present and future regional impact of Pacific
and Atlantic ocean heat transport on the winter Arctic sea ice cover
using simulations from seven single-model large ensembles. We find
strong model agreement for an expanding influence of ocean heat
transport through the Bering Strait and the Barents Sea under continued
sea ice retreat. Model differences can be related to mean volume
transport and inflow temperature, mean sea ice state, and upper ocean
stratification. Our work highlights the increasing importance of the
Pacific and Atlantic water inflows to the Arctic Ocean and indicates
that their future influence regions will be separated by the Lomonosov
Ridge.