OK. Panic over.

From the BBC:

The collapse of a major polar ice sheet will not raise global sea levels as much as previous projections suggest, a team of scientists has calculated.

Writing in Science, the researchers said that the demise of the West Antarctic Ice Sheet (WAIS) would result in a sea level rise of 3.3m (10 ft). Previous estimates had forecast a rise in the region of five to six metres... When the idea first emerged in the late 1970s, it was estimated that global sea level would rise by five metres if the WAIS collapsed. Current projections suggest that a complete collapse of WAIS would result in an increase of up to six metres.

But Professor Bamber said that no-one had revisited the calculation, despite new data sets becoming available, and scientists developing a better understanding of the dynamics in the vast ice sheets. The original estimates were based on "very basic ice thickness data", he explained. "Ice thickness data gives you information about the depth of the bedrock underneath the ice sheet. Over the past 30 years, we have acquired much more ice thickness data over the whole of Antarctica, particularly over West Antarctica. We also have much better surface topography..."

Responding to Professor Bamber's paper in Science, British Antarctic Survey science leader Dr David Vaughan described the findings as "quite sound".

"But for me, the most crucial question is not solely about the total amount of ice in West Antarctica, because that might take several centuries to be lost to the ocean," he told BBC News. "The crucial question is how much ice could be lost in 100-200 years; that's the sea level rise we have to understand and plan for. Even with this new assessment the loss of a fraction of WAIS over those timescales would have serious consequences and costs that we've only really just begun to understand."

So they're pencilling in a 3.3 metre rise over several centuries? Due, WTF? That's hardly something to terrify your children with, is it? They'll have to do a bit of serious rewriting to make it a bit scarier, methinks.