So says the Beeb. And they have a cute picture of whales next to icebergs to prove it. It would be natural to think this was occaisioned by That East Antarctic mass loss, in full (i.e. the new GRACE results) but apparently not, it is just a coincidence: Sea levels are likely to rise by about 1.4m (4ft 6in) globally by 2100 as polar ice melts, according to a major review of climate change in Antarctica. Conducted by the Scientific Committee on Antarctic Research (SCAR), it says that warming seas are accelerating melting in the west of the continent. . Before I continue onwards let me quote Two years ago, the Intergovernmental Panel on Climate Change (IPCC) projected that the global average sea level would probably rise by 28-43 cm (11-16in) by the end of the century. But it acknowledged this figure was almost certainly too low, because it was impossible to model “ice dynamics” – the acceleration in ice melting projected to occur as air and water temperatures rise. Launching the SCAR report in London, lead editor John Turner from the British Antarctic Survey (BAS) suggested that observations on the ground had changed that picture, especially in parts of the West Antarctic ice sheet. “Warmer water is getting under the edges of the West Antarctic ice sheet and accelerating the flow of ice into the ocean,” he said. I do this merely to ask if you know a Top Fact about John Turner? He is very fond of donkeys. Now, back to the schedule.
So, the SCAR release is Antarctic Climate Change and the Environment and that is supported by the BAS press release (read it now folks – they have an irritating habit of moving them around every five minutes). On the off chance that you don’t want to read a 20 Mb pdf download, they helpfully provide a top 10 points list in BIG SHOUTY CAPITALS for the hard of understanding. I’ll leave you to read most of that for yourself (NN will like the bit about sea ice). They reckon that The predicted warming [to 2100] of around 3º C is not enough to cause melting across most of the ice sheet but that Loss of ice from the West Antarctic ice sheet is likely to contribute some tens of centimetres to global sea level by 2100… This is expected to contribute to a projected total sea level rise of up to 1.4 metres by 2100.
At this point we go back to the title of the Beeb’s story and say Aha! Yes: you’ve phrased that really very carefully. “Major sea level rise likely as Antarctic ice melts”. Not *because* but *as*. In that case, they ar relying on ~1.2m of SLR from misc sources to 2100, plus some more from Antarctica, and that is within the bounds of the reasonble.
Incidentally, have you noticed how exciting things have got recently? I’m sure only half a year ago I was bemoaning the lack of cliamte stuff, and now busloads are coming along all at once. It must be Copenhagen (argh! Oh no! I’ve said the word and I said I wouldn’t).