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Landfast Sea Ice Extent Along the East Antarctic Coast
Reference
Fraser, A.D., Massom, R.A., Michael, K.J., Galton-Fenzi, B.K. and Lieser, J.L. 2012. East Antarctic landfast sea ice distribution and variability, 2000-08. Journal of Climate 25: 1137-1156.

Background
The authors write that "landfast sea ice (fast ice) is sea ice that is held stationary (fast) by being attached to coastal features (e.g., the shoreline, glacier tongues, and ice shelves), grounded icebergs, or grounded over shoals," and that "it is a preeminent feature of the Antarctic coastal zone and an important interface between the ice sheet and pack ice/ocean." They also state that variability in fast ice extent "is likely a sensitive indicator of climate change," citing Murphy et al. (1995), Heil et al. (2006) and Mahoney et al. (2007); but they indicate that "despite the physical significance of fast ice, it is currently not represented in global climate circulation models or coupled ice-ocean-atmosphere models."

What was done
In an effort designed to draw more attention to this important but largely-neglected feature of earth's current climatic state, Fraser et al. developed "the first continuous, high spatiotemporal resolution time series of landfast sea ice extent along the East Antarctic coast for the period March 2000-December 2008," based on "consecutive 20-day cloud-free Moderate Resolution Imaging Spectroradiometer (MODIS) composite images."

What was learned
In terms of overall landfast sea ice extent across the entire East Antarctic region (from 10°W to 172°E), as the five Australian researchers describe it, "there has been a statistically significant increase (at the 99% confidence level) of 1.43 0.3% per year," and they say that the regional short-term trends for different sectors of the coast "broadly agree with the longer-term (1979-2008) trend in overall sea ice (comprising both pack ice and fast ice) extent/area (e.g., Cavalieri and Parkinson, 2008; Comiso, 2009)."

What it means
Evidence continues to accumulate for the continuing multi-decadal growth of both pack ice and fast ice across the entire East Antarctic region, which is something one would not expect to see in a world experiencing what climate alarmists describe as "unprecedented global warming."

References
Cavalieri, D.J. and Parkinson, C.L. 2008. Antarctic sea ice variability and trends, 1979-2006. Journal of Geophysical Research 113: 10.1029/2007JC004564.

Comiso, J. 2009. Variability and trends of the global sea ice cover. In: Thomas, D. and Dieckmann, G. (Eds.). Sea Ice, 2nd Edition. Wiley-Blackwell, pp. 205-246.

Heil, P. 2006. Atmospheric conditions and fast ice at Davis, East Antarctica: A case study. Journal of Geophysical Research 111: 10.1029/2005JC002904.

Mahoney, A., Eicken, H., Gaylord, A.G. and Shapiro, L. 2007. Alaska landfast sea ice: Links with bathymetry and atmospheric circulation. Journal of Geophysical Research 112: 10.1029/2006JC003559.

Murphy, E.J., Clarke, A., Symon, C. and Priddle, J.J. 1995. Temporal variation in Antarctic sea-ice: Analysis of a long term fast-ice record from the South Orkney Islands. Deep-Sea Research I 42: 1045-1062.

Reviewed 6 June 2012