LiveScience.com - Greenland Dumps Ice into Sea at Faster Pace
So the above article notes that the Greenland glaciers are falling into the sea at a much faster rate. But it ends with this observation:
The only way to stem the loss of ice would be for Greenland to receive increased amounts of snowfall, according to Julian Dowdeswell of the University of Cambridge, who wrote an accompanying article.
It doesn't mention what the other article said.
But over at Tech Central Station, they have a story that points out this:
Another paper on this subject was published by Science just last year. Ola Johannessen did not consider direct ice lost by glaciers into the ocean but instead only focused on elevations changes. Johannssen showed that increasing snowfall in Greenland was leading to greater ice accumulations than had previously been measured and this was acting to slow Greenland's contribution to sea level rise. It was conspicuously ignored in this new report...
Why would Science publish this paper with no reference to Johannessen's earlier paper showing that Greenland is accumulating ice at a rate of about 5.4±0.2cm/year? Johannessen even used data from some of the same satellites. What's more, Johannessen used real data and Hanna et al., cited by Rignot, used a model of surface melt.
Consider what would have happened had the latest study included the ice and snow gains observed by Johannessen (and ignored the losses modeled by Hanna et. al.). Johannnessen's increase of 5.4cm/year averaged over Greenland converts to about 75km3/year. Rignot and Kanagaratnam could have subtracted Johannessen's gains. If they had done so, the total volume of ice loss from Greenland would only have become positive during the last 5 years, totaling 17km3 in 2000 and 92km3 in 2005. This translates to a sea level rise contribution of 0.04mm in 2000 and 0.23mm in 2005 -- values much less dramatic than those they published.
All very interesting. Don't expect most of the media to go into such subtleties though.
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