Publication Date:
2015-09-28
Description:
Antarctic ice sheet mass loss and thus part of global sea-level rise is related to enhanced ice
stream discharge to the fringing ice shelves. The transfer of ice into the ocean occurs via
iceberg calving and ice shelf basal melting. For decades the balance of both terms was
assumed to be in favor of the calving, but recent results, based on remote sensing, revealed
that basal melting seems to be at least of similar importance. A recent model study indicates
that future atmospheric conditions in the southern Weddell Sea may switch the continental
shelf, formerly dominated by the formation of cold saline waters, to one influenced by warm
open ocean waters with consequences for the basal mass flux and ice shelf/ice sheet
dynamics. Here, we continue the simulations showing a warming of the Filchner-Ronne Ice
Shelf cavity, applying 20th-century atmospheric and basal mass flux forcing at different future
points in time. Our numerical study indicates that once the system reaches the 'warm phase',
a positive meltwater feedback stabilizes the shelf circulation such that only a reduction to
20th century basal mass flux can stop warm water from penetrating onto the continental shelf
and into the sub-ice cavity. This has implications for the future of the Antarctic Ice Sheet,
since a major decrease of basal melting only can be achieved by a significant disintegration
of the floating portion of the ice sheet.
Repository Name:
EPIC Alfred Wegener Institut
Type:
Conference
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notRev
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info:eu-repo/semantics/conferenceObject
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