Sunday, August 16, 2009

Updates on Climate Change

Things I've been bugging a few people with by e-mail:

For math majors: "Is Global Temperature a Random Walk?"

Of course nothing can really be settled by talking about local weather, but: eastern North America had a cool July, certain spots in North America had a hot July, North America as a whole was on the cool side.

A funny piece in The Star points out that Environment Canada has been wrong all summer about the Greater Toronto Area: it's going to be hot; there's not going to be much rain.

Repeating an earlier link here, because I like it so much: Experts on Canada's Arctic have found no actual evidence of global warming up there so far. Cold War data that was supposed to show the Arctic ice was thinning came from U.S. military vessels, which always took samples from basically the same kind of area:

"Nobody really quite noticed the submarines were running across the outside edges of the Canadian archipelago," the islands scattered across Canada's Far North, "where for all we know, the ice was getting thicker," Eert says.

The ice thinned in 2007--probably because it was pushed to a warmer spot--but the modellers jumped to conclusions, and "fudged" data. Of course the reporter who writes this up (Paul Watson, founder and president of the Sea Shepherd Conservation Society), says the experts are sure to find evidence of global warming--some day.

After years of reports that vast areas of Arctic ice are melting as the seawater below, and air above, warm up, scientists have discovered that dramatic changes in the past three years are the result of shifting winds, perhaps caused by climate change.

Enormous amounts of ice have "been exported from the Arctic," driven by winds that are shifting as the climate changes, which pushed the ice into ocean currents that delivered it to the North Atlantic, Eert says.

"The multi-year ice in the polar pack didn't melt in the Arctic Ocean,'' she says. "It moved out and what's left in the Arctic is thinner than it was."

That doesn't mean some Arctic ice isn't disappearing altogether, just that the process is not as simple as some reports suggest, Eert says.

Old ice that has shifted south from Greenland may have a counter-effect on the climate, which is just one of the many pieces of a very complex jigsaw puzzle that scientists are trying to piece together as they attempt to predict the effects of global warming.

"The guys who are running the long-term climate models have a tough problem," Eert says. "They're looking at really long time scales, and as result they can't look at a lot of details for each year.

"In order to get the results before you die, you have to fudge some things. And what they fudge is the small-scale stuff. But it turns out that probably the small-scale stuff is important and fudging it gives you wrong answers."

Of course this doesn't prevent the Star, in other articles, from stating matter of factly that if one specific part of the Arctic loses ice, the whole world is clearly warming up.

A relief for those of us brought up on Walt Disney movies: polar bears as a whole are apparently in little or no danger.

Even according to the doomsayers, the total polar bear population before recent changes was somewhere in the range 20,000-25,000. The total population now? The same.

My guru is Anthony Watts, who links to various sources. A new study indicates that heat in the oceans (covering much of the surface of the earth) has been fluctuating every few years. "These facts are not found among the theoretical predictions," which I think means facts on the ground are not successfully predicted by computer models, including the IPCC model. If so, heat in the oceans presumably bears no relationship (so far) to man-made CO2.

The total number of tornadoes in the U.S. went up from 1950 to 2006, but the most severe tornados, F2 to F5, did not. There is good evidence that the former finding resulted from improved reporting of smaller storms, rather than an actual increase in storms. On the somewhat different front of tropical storms: again, improved reporting resulted in an increase in the number of reported tropical storms over several decades. A closer look suggests it is unlikely that there was any actual increase in storms.

Data, data, data. The oft-repeated claim that there was a warming trend in the twentieth century depends heavily on surface weather stations in the U.S. To say the data from these stations is questionable is an understatement.

2009? There has not been a single tropical storm in the Atlantic.

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