Tom, you may want to take a look at Overpeck et al. 2006 (Hansen relies on this study for example in "Climate Change and Trace Gases"). I'm lazy and simply copy and paste something I'm writing at the moment:
Jonathan Overpeck et al. (2006) try to compare present and future conditions with the last interglacial period (LIG), a warm era between 129,000 and 118,000 years ago. That time, sea levels were between 4 and more than 6 m higher than today. For Greenland, the team concludes that with 3.5°C global and hence about 5°C local warming, "the high northern latitudes around Greenland will be as warm as or warmer than they were 130,000 years ago and hence warm enough to melt at least the large portions of the [Greenland Ice Sheet] that apparently melted during the LIG" (Overpeck et al. 2006: 1748). For the Antarctic, the situation could also worsen substantially, leading the authors to conclude that "a threshold triggering many meters of sea-level rise could be crossed well before the end of this century" (ibid.: 1750). Source: Overpeck, Jonathan T., Bette L. Otto-Bliesner, Gifford H. Miller, Daniel R. Muhs, Richard B. Alley, and Jeffrey T. Kiehl (2006): Paleoclimatic Evidence for Future Ice-Sheet Instability and Rapid Sea- Level Rise, in: Science, Vol. 311, 24 March, pp. 1747-1750, see under http://www.sciencemag.org/cgi/content/abstract/311/5768/1747 Before I started to look into sea level rise more intensively a few weeks ago, I was rather wary of anything more than 1m this century. But now, with the Arctic sea ice shrinking faster than anyone had predicted before, glaciers reacting dynamically like no one had predicted before, and more than a quarter of Greenland's surface area now subject to snow melting, I think Hansen's point is supported by some evidence. If 5°C global warming from the last ice age to the holocene resulted in 120m sea level rising, I think that only 1m due to the likely 3-X°C we can expect this century seems pretty low. Whether it's going to be as rapid as during meltwater pulse 1A of course I can't tell. Back then, sea levels rose by 1m every 20 years. But given the sheer size of global warming, I would rather like to see one who can rule out this possibility instead of asking for someone to prove that it could happen. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups Global Change ("globalchange") newsgroup. Global Change is a public, moderated venue for discussion of science, technology, economics and policy dimensions of global environmental change. Posts will be admitted to the list if and only if any moderator finds the submission to be constructive and/or interesting, on topic, and not gratuitously rude. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/globalchange -~----------~----~----~----~------~----~------~--~---
