EclectEcon

From the journal, CO2 Science (which clearly has an axe to grind, so do not accept this information as definitive; but do not ignore it either! [via Melanie Phillips]:

Reference: Wingham, D.J., Shepherd, A., Muir, A. and Marshall, G.J. 2006. Mass balance of the Antarctic ice sheet. Philosophical Transactions of the Royal Society A 364: 1627-1635.

What was done: The authors "analyzed 1.2 x 108 European remote sensing satellite altimeter echoes to determine the changes in volume of the Antarctic ice sheet from 1992 to 2003." This survey, in their words, "covers 85% of the East Antarctic ice sheet and 51% of the West Antarctic ice sheet," which together comprise "72% of the grounded ice sheet.""

What was learned: Wingham et al. report that "overall, the data, corrected for isostatic rebound, show the ice sheet growing at 5 ± 1 mm year-1." To calculate the ice sheet's change in mass, however, "requires knowledge of the density at which the volume changes have occurred," and when the researchers' best estimates of regional differences in this parameter are used, they find that "72% of the Antarctic ice sheet is gaining 27 ± 29 Gt year-1, a sink of ocean mass sufficient to lower [authors' italics] global sea levels by 0.08 mm year-1." This net extraction of water from the global ocean, according to Wingham et al., occurs because "mass gains from accumulating snow, particularly on the Antarctic Peninsula and within East Antarctica, exceed the ice dynamic mass loss from West Antarctica."

What it means: Contrary to all the horror stories one hears about global warming-induced mass wastage of the Antarctic ice sheet leading to rising sea levels that gobble up coastal lowlands worldwide, the most recent decade of pertinent real-world data suggest that forces leading to just the opposite effect are apparently prevailing, even in the face of what climate alarmists typically describe as the greatest warming of the world in the past two millennia or more. [emphasis added]
Reviewed 8 November 2006

Melanie Phillips goes on to say,

The mismatch between what the science actually tells us and what campaigners tell us the science tells us has become so extreme that the climate change lobby itself is starting to crack apart. One of its gurus, Mike Hulme, Director of the Tyndall Centre for Climate Change Research, has turned on his own side and denounced the current hysteria over global warming (singling out the Independent newspaper by name) as manipulation and group-think... [click here for her quotations from this source; this portion is near the end of her posting.]

Addendum 1: I am not fully persuaded by the arguments either way. My inclination is that the challengers are on fairly solid ground, but I'm not sure. For more on how nasty the debates can get, see this, to which Craig Newmark linked today.

Addendum 2: As Chris Essex wrote to me this morning, "The number 27 ± 29 Gt year-1 says a lot about what we really know or don't know." 8-)