Fram Strait sea ice outflow

We summarize 24 years (1978–2002) of ice export estimates and examine, over a 9‐year record, the associated variability in the time‐varying upward‐looking sonar (ULS) thickness distributions of the Fram Strait. A more thorough assessment of the PMW (passive microwave) ice motion with 5 years of synt...

Full description

Saved in:
Bibliographic Details
Published in:Journal of Geophysical Research - Oceans 2004-01, Vol.109 (C1), p.C01009-n/a
Main Authors: Kwok, R., Cunningham, G. F., Pang, S. S.
Format: Article
Language:English
Subjects:
Arctic and Antarctic oceanography
Climate and interannual variability
Earth, ocean, space
Exact sciences and technology
Fram Strait
Global Change
ice export
ice thickness
Marine
Oceanography
Oceans
Remote sensing and electromagnetic processes
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We summarize 24 years (1978–2002) of ice export estimates and examine, over a 9‐year record, the associated variability in the time‐varying upward‐looking sonar (ULS) thickness distributions of the Fram Strait. A more thorough assessment of the PMW (passive microwave) ice motion with 5 years of synthetic aperture radar (SAR) observations shows the uncertainties to be consistent with that found by Kwok and Rothrock [1999], giving greater confidence to the record of ice flux calculations. Interesting details of the cross‐strait motion profiles and ice cover characteristics revealed by high‐resolution SAR imagery are discussed. The average annual ice area flux over the period is 866,000 km2/yr. Between the 1980s and 1990s, the decadal difference in the net exported ice area is ∼400,000 km2, approximately half the annual average. Except for the years with extreme negative NAO, correlation of winter ice area export with the NAO index remains high (R2 = 0.62). With thickness estimates from ULS moorings, we estimate the average annual ice volume flux (8 years) to be ∼2218 km3/yr (∼0.07 Sv). Over the ∼9‐year ULS ice thickness data set, there is an overall decrease of 0.45 m in the mean ice thickness over the entire time series and a decrease of 0.23 m over the winter months (December through March). Correspondingly, the mode of the MY ice thickness exhibits an overall decrease of 0.55 m and a winter decrease of 0.42 m. These are significant trends. Whether these trends are indicative of the thickness trends of the Arctic Ocean is examined, as the time‐varying behavior of the monthly ULS thickness distributions can be related not only to the seasonal cycle in the basal growth and melt, but also to the magnitude and pattern of ice motion in the Arctic Ocean, and the proximity of the ULS moorings to the ice edge.
ISSN:0148-0227
2169-9275
2156-2202
2169-9291
DOI:10.1029/2003JC001785