Publication Date:
2024-05-01
Description:
We present a 700 km airborne electromagnetic survey of late-spring fast ice and sub-ice platelet
layer (SIPL) thickness distributions from McMurdo Sound to Cape Adare, providing a first-time inventory
of fast ice thickness close to its annual maximum. The overall mode of the consolidated ice (including snow)
thickness was 1.9 m, less than its mean of 2.6 ± 1.0 m. Our survey was partitioned into level and rough ice,
and SIPL thickness was estimated under level ice. Although level ice, with a mode of 2.0 m and mean of
2.0 ± 0.6 m, was prevalent, rough ice occupied 41% of the transect by length, 50% by volume, and had a
mode of 3.3 m and mean of 3.2 ± 1.2 m. The thickest 10% of rough ice was almost 6 m on average, inclusive
of a 2 km segment thicker than 8 m in Moubray Bay. The thickest ice occurred predominantly along the
northwestern Ross Sea, due to compaction against the coast. The adjacent pack ice was thinner (by ∼1 m)
than the first-year fast ice. In Silverfish Bay, offshore Hells Gate Ice Shelf, New Harbor, and Granite Harbor,
the SIPL transect volume was a significant fraction (0.30) of the consolidated ice volume. The thickest 10%
of SIPLs averaged nearly 3 m thick, and near Hells Gate Ice Shelf the SIPL was almost 10 m thick, implying
vigorous heat loss to the ocean (∼90 W m −2). We conclude that polynya-induced ice deformation and
interaction with continental ice influence fast ice thickness in the western Ross Sea.
Repository Name:
EPIC Alfred Wegener Institut
Type:
Article
,
isiRev
Format:
application/pdf
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