Thursday, July 02, 2009
Hello, Pot? This is the Kettle--You're Black.
Some aspects of climate change are progressing faster than was expected a few years ago - such as rising sea levels, the increase of heat stored in the ocean and the shrinking Arctic sea ice.
Roger Pielke, Sr. thought each of the three so called worsening aspects of climate change was false and he wrote on Anthony Watt's site detailing his reasons for thinking that:
1. Sea level has actually flattened since 2006;
2. There has been no statistically significant warming of the upper ocean since 2003; and,
3. [S]ee the Northern Hemisphere Sea Ice Anomaly from the University of Illinois Cyrosphere Today website. Since 2008, the anomalies have actually decreased.
Commenters on Real Climate responded. It was tough to call a winner of that round. For each set of statistics Pielke could marshal, the Warmies had a different set. Part of the problem was with the imprecision of the offending sentence above. The 2009 report updated the latest IPCC report from 2007, but there are a series of IPPC reports going back to 1990. For every recent (i.e., 2 year old) prediction, the Real Climate writers were able to show older predictions which were indeed less than the data they cited. I though this was unfair, as the offending sentence said that the rising, warming, and melting were worse than "a few years ago". That sounded like things had indeed worsened since the 2007 report. Two years of change is too short a period from which to establish a trend.
Then there was a second round and what struck me about the writing on Real Climate was the following repeated criticism of Pielke:
First of all, trends over such a short sub-interval of a few years vary greatly due to short-term natural variations, and one could get any result one likes by cherry-picking a suitable interval...[...]
...Pielke is referring to a 5-year period which is too short to obtain statistically robust trends in the presence of short-term variability and data accuracy problems...[...]
And Pielke is again referring to a time span (“since 2008”!) that is far too short to have much to do with climatic trends.
But what was Real Climate saying in the offending sentence? -- that the Warmie scientists had discovered trends, necessarily over just a few years, which revealed some things were worse than just "a few years ago."
So apparently when Warmies discern trends over just a few years, they are significant; but when AGW skeptics discover trends over the same few years, they are bunk.
It's necessary to know the distinction to make sense of the controversy.
Meanwhile, no saint named Kilda has existed or been believed to exist.
See below from an article in Nova:
Rodents tend toward gigantism, while carnivores, lagomorphs (rabbits and hares), and artiodactyls (deer, hippos, and other even-toed ungulates) are more likely to become dwarfed. Overall, amongst mammal species that colonize islands, big ones have a tendency to shrink while small ones are apt to enlarge. Biologists have come to call Foster's generalization the "island rule."
Foster went on to offer tentative explanations as to how at least some of these extraordinary transformations occurred. Islands, he argued, contain fewer species than mainlands and thus fewer numbers of both predators and competitors that might stress a newcomer. "In such situations," he wrote, "it appears that the larger rodent has an advantage."
But how to explain those species that diminish in size? Foster offered one possible answer, and for just one group, the artiodactyls. While rodents are able to control their populations in the absence of predators, hippos and deer and their kind cannot. As a result, artiodactyls are "especially susceptible," Foster felt, to exhausting food resources and occasioning malnutrition and stunting in their young. If, in succeeding generations, smaller individuals met with greater reproductive success, then eventually evolution might begin to favor them, leading to dwarfism.
Also Komodo dragons; Galapagos tortoises; and of course, the giant hissing cockroach of Madagascar; plus the giant rat of Sumatra.
Dr. Kildare was kind of a saint.