Have any of these geniuses actually sat down and calculated how much heat would be required to melt that much ice?
The study, published in the journal Nature: Geoscience, concludes that, globally, mountain glaciers and ice caps are projected to lose 15-27% of their volume by 2100, although the extent of the damage varies widely. The analysis suggests glaciers in the Alps and New Zealand will shrink by more than 70% but shrinkage is predicted to reach about 10% in Greenland and high-mountain Asia.
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Hat-throw estimate: ice-sheet volume 2,850,000 cubic km (683,751 cu miles) at mean annual temperature of say -20C. This is 2.62E+18 kg of ice, at a specific density of say 919 kg/cuM.
To warm it to 0C and melt it will take 20 * 4.18 (approx specific heat of ice) + 333.55 (the melt) = 417.15 kJ/kg of ice, so 1.09E+21 kJ in total.
So, if you could apply work/heat uniformly (eg heat the whole sheet in a microwave) it would take 1.09E+21 kw.seconds. There are 2.84 E+09 seconds approx in the 90 years to 2100, so to melt the entire sheet in the microwave would take 3.85 E+11 kw of absorbed energy (more input energy of course). The oven would have to deliver about 385 million MW throughout the whole 90 years to melt the sheet completely. Total world energy consumption is estimated at 15 terawatts (15 million MW) so melting 10% of the ice-sheet by the end of the century would take at least twice the current total world energy, as delivered energy.
Of course it’s more complex than that – for example ice normally melts at the surface layer (think of how long it takes a compacted snowman to melt).
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Awsome= You are easily awed. No mention of all the glaciers calving ice. This ice immediately displaces ocean water by 90% of its volume. The ice will melt, but doesn´t have to. The compacted snowman analogy is poor and irrelevant. `Ice normally melts at the surface`is a flawed supposition. It melts from below too.
More complex? Indeed, much more complex and worrying.