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Simulated Climate Change on the East Antarctic Ice Sheet
Reference
Nslund, J.O., Fastook, J.L and Holmlund, P. 2000. Numerical modeling of the ice sheet in western Dronning Maud Land, East Antarctica: impacts of present, past and future climates. Journal of Glaciology 46: 54-66.

What was done
The authors used a new 10-km by 10-km data set on ice sheet bed and surface topography for western Dronning Maud Land as input in a time-dependent ice sheet model, which they used to simulate changes in ice sheet volume for this region of the East Antarctic Ice Sheet under six temperature forcing scenarios (5C instant warming, 5C slow warming, 10C warming, 5C instant cooling, 5C slow cooling and 10C cooling) over a period of 20,000 model years.

What was learned
The model yielded a long-term response that required something on the order of 20,000 model years (and perhaps longer) for the ice sheet to fully respond to the six temperature perturbations. The authors thus conclude that the East Antarctic Ice Sheet "may still be adjusting to the climate change that ended the Last Glacial Maximum."

By the end of 20,000 model years, the 5C warming and cooling scenarios produced changes in ice sheet volume that varied by only 1 to 1.5% of the initial ice sheet volume, suggesting that "the investigated part of the [East Antarctic Ice Sheet] does not appear to be very sensitive to present or future climatic changes." Results from the 10C warming and 10C cooling simulations produced larger initial fluctuations in ice volume, but quickly stabilized and returned to near initial conditions at the end of the 20,000 years.

What it means
The results of this study deal a severe blow to climate alarmists who predict catastrophic melting of the polar ice sheets as a consequence of CO2-induced global warming. Even with computer models - which they generally use as the basis for their claims - such a scenario seems a virtual impossibility. In addition, this study demonstrates the difficulty of ascribing recent trends in ice sheet volume to anthropogenic activities, in view of the long time period required for the ice sheet to come to equilibrium following the end of the last glacial maximum.