The decline in arctic sea-ice thickness: Separating the spatial, annual, and interannual variability in a quarter century of submarine data
Article first published online: 3 MAY 2008
Copyright 2008 by the American Geophysical Union.
Journal of Geophysical Research: Oceans (1978–2012)
Volume 113, Issue C5, May 2008
How to Cite
2008), The decline in arctic sea-ice thickness: Separating the spatial, annual, and interannual variability in a quarter century of submarine data, J. Geophys. Res., 113, C05003, doi:10.1029/2007JC004252., , and (
- Issue published online: 3 MAY 2008
- Article first published online: 3 MAY 2008
- Manuscript Accepted: 19 DEC 2007
- Manuscript Revised: 14 SEP 2007
- Manuscript Received: 29 MAR 2007
- Ice thickness;
- multiple regression;
- generalized least squares
 Naval submarines have collected operational data of sea-ice draft (93% of thickness) in the Arctic Ocean since 1958. Data from 34 U.S. cruises are publicly archived. They span the years 1975 to 2000, are equally distributed in spring and autumn, and cover roughly half the Arctic Ocean. The data set is strong: we use 2203 values of mean draft, each value averaged over a nominal length of 50 km. These values range from 0 to 6 m with a standard deviation of 0.99 m. Multiple regression is used to separate the interannual change, the annual cycle, and the spatial field. The solution gives a climatology for ice draft as a function of space and time. The residuals of the regression have a standard deviation of 0.46 m, slightly more than the observational error standard deviation of 0.38 m. The overall mean of the solution is 2.97 m. Annual mean ice draft declined from a peak of 3.42 m in 1980 to a minimum of 2.29 m in 2000, a decrease of 1.13 m (1.25 m in thickness). The steepest rate of decrease is −0.08 meters per year (m/a) in 1990. The rate slows to −0.007 m/a at the end of the record. The annual cycle has a maximum on 30 April and a peak-to-trough amplitude of 1.06 m (1.12 m in thickness). The spatial contour map of the temporal mean draft varies from a minimum draft of 2.2 m near Alaska to a maximum just over 4 m at the edge of the data release area 200 miles north of Ellesmere Island.