Science a GoGo's Home Page Forums General Discussion Climate Change Forum The difference between science and politics

Glaciers Not On Simple, Upward Trend Of Melting Science Daily ? Two of Greenland's largest glaciers shrank dramatically and dumped twice as much ice into the sea during a period of less than a year between 2004 and 2005. And then, less than two years later, they returned to near their previous rates of discharge. The variability over such a short time, reported online Feb. 9 on Science magazine's Science Express, underlines the problem in assuming that glacial melting and sea level rise will necessarily occur at a steady upward trajectory, according to lead author Ian Howat, a post-doctoral researcher with the University of Washington's Applied Physics Laboratory and the University of Colorado's National Snow and Ice Data Center. The paper comes a year after a study in the journal Science revealed that discharge from Greenland's glaciers had doubled between 2000 and 2005, leading some scientists to speculate such changes were on a steady, upward climb. "While the rates of shrinking of these two glaciers have stabilized, we don't know whether they will remain stable, grow or continue to collapse in the near future," Howat says. That's because the glaciers' shape changed greatly, becoming stretched and thinned. For the full story Click Here . The difference is whether one accepts all the data or filters it to meet a preconceived notion of reality.

DA Doesn't this illustrate very well the difficulty of prediction with regard to climate change? The variability which is so much a part of the events makes accuracy of prediction almost impossible. Is it even sensible to forecast from the facts taken over 3 years? Someone explained to me the difference between climate and weather, and this (a 3 year cycle) seems to be an example of the weather. It seems to me to be naive to assume that anything can be determined to be steady or clear over such a short time. Localised events will skew the overall picture, but the longer outlook will determine the results more accurately.

At the moment I think that there seems to be a lot of filtering (and hoping) going on.

It illustrates the difficulty rather well which is why I thought it important to post it.

But variability is well known and something climatologists deal with as part of their work. Take a look at the stock market to see something rather similar. In any finite set it may look one way or the other. But, on average, the trend is the same as that of global temperatures.