James Hansen et al in new papers say: "The m...

2011-06-10T08:52:11.868+10:00

James Hansen et al in new papers say:

"The most reliable indication of the imminence of multi-meter sea level rise may be provided by empirical evaluation of the doubling time for ice sheet mass loss. Mass loss by the Greenland and Antarctic ice sheets can be deduced from satellite measurements of Earth's gravity field. Fig. 8 shows mass loss reported by Velicogna (2009). The most important curves are the 12-month running means of the annual mass change of the Greenland and Antarctic ice sheets (heavy blue lines in Figs. 8c and 8d), which average out the annual cycle. These data records are too short to provide a reliable evaluation of the doubling time, but, such as they are, they yield a best fit doubling time for annual mass loss of 5-6 years for both Greenland and Antarctica, consistent with the approximate doubling of annual mass loss in the period 2003-2008. There is substantial variation among alternative analyses of the gravity field data (Sorensen and Forsberg, 2010), but all analyses have an increasing mass loss with time, providing at least a tentative indication that long-term ice loss mass will be non-linear. We conclude that available data for the ice sheet mass change are consistent with our expectation of a non-linear response, but the data record is too short and uncertain to allow quantitative assessment. The opportunity for assessment will rapidly improve in coming years if high-precision gravity measurements are continued."

SLR from Greenland and Antaarctic over last decade has been 1.5mm/year approx.

If doubling time is 10 years, than yields about 1.5 metres to 2100 plus thermal expansion.

If you take a more conservative 1mm and take doubling time of 8 years, than yields about 4 metres to 2100 plus thermal expansion (at least 1m), which was Hansen's ballpark of 5 metres from 4-5 years ago when he was writing about scientific reticence and sea-level rises.

2011-06-09T09:27:25.661+10:00

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Given the report on the arctic sea ice death spira...

2011-06-08T21:36:16.050+10:00

Given the report on the arctic sea ice death spiral last week, I would have thought that 2 metres by 2050 is now on the cards, and besides I cannot see that cities as we know them will be worrying too much about the sea coming up when they are suffering shortages of food and energy and medicines and other extreme climatic developments.

Of course the sea level doesn't change. Height...

2011-06-08T20:07:38.410+10:00

Of course the sea level doesn't change. Heights above sea level are measured.... above sea level. Which means that actually the land is sinking. Now all we need to do is to fund an expedition to find the giant plug at the bottom of the ocean to let the water out and we'll all be right!

Comments on climate code red: Australian government deliberately underestimating...

James Hansen et al in new papers say: "The m...

Given the report on the arctic sea ice death spira...

Of course the sea level doesn't change. Height...