Science Source

Regions of rapid sea ice change: An inter-hemispheric seasonal comparison

Resolves ice edge changes on space/time scales relevant for investigating seasonal ice-ocean feedbacks and focuses on spatio-temporal changes in the timing of annual sea ice retreat and advance over 1979/80 to 2010/11
Finds where Arctic sea ice decrease is fastest, the sea ice retreat is now nearly 2 months earlier and subsequent advance more than 1 month later (compared to 1979/80), resulting in a 3-month longer summer ice-free season. In the Antarctic Peninsula and Bellingshausen Sea region, sea ice retreat is more than 1 month earlier and advance 2 months later, resulting in a more than 3-month longer summer ice-free season
Finds in contrast, in the western Ross Sea (Antarctica) region, sea ice retreat and advance are more than 1 month later and earlier respectively, resulting in a more than 2 month shorter summer ice-free season
Finds a strong correspondence at latitudes mostly poleward of 70° (N/S) between anomalies in the timings of sea ice retreat and subsequent advance, but little correspondence between advance and subsequent retreat (regardless of trend magnitude or direction)
Results support a strong ocean thermal feedback in autumn in response to changes in spring sea ice retreat
Model calculations suggest different net ocean heat changes in the Arctic versus Antarctic where autumn sea ice advance is 1 versus 2 months later
Discusses and compares ocean-atmosphere changes, particularly in boreal spring and austral autumn (i.e., during ∼March-May), as well as possible inter-hemispheric climate connections