Monday, June 20, 2011

Over-Representation of Factual Presentations

One of the fears expressed by people concerned about global warming is that melting ice caps will cause sea levels to rise and cover large swaths of coastline with water by the end of the century or thereabouts. In his book, An Inconvenient Truth, Al Gore predicted that the seas were going to rise twenty feet submerging Manhattan Island by early in the next century.

An article at Fox News casts doubt on this and similar fears about rising sea levels:
Is climate change raising sea levels, as Al Gore has argued -- or are climate scientists doctoring the data?

The University of Colorado’s Sea Level Research Group decided in May to add 0.3 millimeters -- or about the thickness of a fingernail -- every year to its actual measurements of sea levels, sparking criticism from experts who called it an attempt to exaggerate the effects of global warming.

"Gatekeepers of our sea level data are manufacturing a fictitious sea level rise that is not occurring," said James M. Taylor, a lawyer who focuses on environmental issues for the Heartland Institute.

Steve Nerem, the director of the widely relied-upon research center, told FoxNews.com that his group added the 0.3 millimeters per year to the actual sea level measurements because land masses, still rebounding from the ice age, are rising and increasing the amount of water that oceans can hold.

"We have to account for the fact that the ocean basins are actually getting slightly bigger... water volume is expanding," he said, a phenomenon they call glacial isostatic adjustment (GIA).
Global water volume is increasing but the land is rising so the net change in sea level is minor. The impression people are getting, however, is that sea levels are rising rapidly relative to our coastlines and that we'll soon be inundated. This isn't happening, apparently, or at least not at rates that would justify concern.

Nerem acknowledges that:
"If we correct our data to remove [the effect of rising land], it actually does cause the rate of sea level (a.k.a. ocean water volume change) rise to be bigger. The adjustment is trivial, and not worth public attention."

"For the layperson, this correction is a non-issue and certainly not newsworthy… [The] effect is tiny -- only 1 inch over 100 years."
Well. That certainly makes a difference. Instead of facing the prospect of twenty foot sea level rises in the next hundred years the sea is really only going to rise about an inch. Taylor urges people to be wary of sea level rise estimates:
"When Al Gore talks about Manhattan flooding this century, and 20 feet of sea level rise, that’s simply not going to happen. If it were going to happen, he wouldn’t have bought his multi-million dollar mansion along the coast in California."
By the way, when Mr. Gore came out with the movie based on his book he said this:
“Nobody is interested in solutions if they don’t think there’s a problem. Given that starting point, I believe it is appropriate to have an over-representation of factual presentations on how dangerous it is, as a predicate for opening up the audience to listen to what the solutions are, and how hopeful it is that we are going to solve this crisis.” (emphasis mine)
An "over-representation of factual presentations" is a euphemism for "lie". It's pretty hard to trust people you know will lie to you in order to persuade you to accept what they're selling.