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I'd like to check this statement from the article: "'Many geologists, we’re looking at the possibility of a ten-to-thirty-foot range [of sea-level rise] by the

I'd like to check this statement from the article: "'Many geologists, we’re looking at the possibility of a ten-to-thirty-foot range [of sea-level rise] by the end of the century,' he told me." I have not seen any published figure that high. I've actually been rather surprised at how LOW many predictions of sea-level rise are for the century ending in the year 2100. The United States Environmental Protection Agency writes,[1] "Since 1870, global sea level has risen by about 7.5 inches. Estimates of future sea level rise vary for different regions, but global sea level for the next century is expected to rise at a greater rate than during the past 50 years. Studies project global sea level to rise by another 1 to 4 feet by 2100, with an uncertainty range of 0.66 to 6.6 feet." The Intergovernmental Panel on Climate Change document on sea level rise[2] projects a lot of uncertainty, but doesn't seem to predict such major changes in sea level. [1] http://www3.epa.gov/climatechange/science/future.html#sealevel http://www3.epa.gov/climatechange/science/future.html#sealev... [2] https://www.ipcc.ch/pdf/unfccc/cop19/3_gregory13sbsta.pdf https://www.ipcc.ch/pdf/unfccc/cop19/3_gregory13sbsta.pdf

mturmon 11y ago
I think you have a good point about the generally-accepted ranges for sea level rise being smaller than the figure Wanless mentions. The thing that has people worried is that the mass losses from glaciers are large, not well-accounted for, and they could accelerate. (The sea level rise from volume increases due to temperature rise of the oceans are much smaller and much easier to account for.) Looking carefully at the IPCC summary (your [2]), it seems that 1m is the current top of the likely range for rise by 2100, even including possible loss of Greenland and the Antarctic glaciers. Here's a sample of the reactions to a recent, high-profile paper that put forward a 3m rise by 2100: http://news.nationalgeographic.com/2015/07/150721-james-hansen-sea-level-rise-climate-change-global-warming-science/ http://news.nationalgeographic.com/2015/07/150721-james-hans...
- Daishiman 11y ago
  The fundamental problem is that iceberg collapse usually follows an exponential model, but as with all exponential formulas, a small change in the constants yields humongous differences in the long run.

mturmon 11y ago

I think you have a good point about the generally-accepted ranges for sea level rise being smaller than the figure Wanless mentions. The thing that has people worried is that the mass losses from glaciers are large, not well-accounted for, and they could accelerate. (The sea level rise from volume increases due to temperature rise of the oceans are much smaller and much easier to account for.) Looking carefully at the IPCC summary (your [2]), it seems that 1m is the current top of the likely range for rise by 2100, even including possible loss of Greenland and the Antarctic glaciers. Here's a sample of the reactions to a recent, high-profile paper that put forward a 3m rise by 2100: http://news.nationalgeographic.com/2015/07/150721-james-hansen-sea-level-rise-climate-change-global-warming-science/ http://news.nationalgeographic.com/2015/07/150721-james-hans...

Daishiman 11y ago
The fundamental problem is that iceberg collapse usually follows an exponential model, but as with all exponential formulas, a small change in the constants yields humongous differences in the long run.