Plus Ça (Climate) Change (Inconvenient history/common sense)

Wall Street Journal ^ | February 21, 2007 | PETE DU PONT

[yoe]

When Eric the Red led the Norwegian Vikings to Greenland in the late 900s, it was an ice-free farm country--grass for sheep and cattle, open water for fishing, a livable climate--so good a colony that by 1100 there were 3,000 people living there. Then came the Ice Age. By 1400, average temperatures had declined by 2.7 degrees Fahrenheit, the glaciers had crushed southward across the farmlands and harbors, and the Vikings did not survive.

Such global temperature fluctuations are not surprising, for looking back in history we see a regular pattern of warming and cooling. From 200 B.C. to A.D. 600 saw the Roman Warming period; from 600 to 900, the cold period of the Dark Ages; from 900 to 1300 was the Medieval warming period; and 1300 to 1850, the Little Ice Age.

During the 20th century the earth did indeed warm--by 1 degree Fahrenheit. But a look at the data shows that within the century temperatures varied with time: from 1900 to 1910 the world cooled; from 1910 to 1940 it warmed; from 1940 to the late 1970s it cooled again, and since then it has been warming. Today our climate is 1/20th of a degree Fahrenheit warmer than it was in 2001.

[snip] Statistics suggest that while there has indeed been a slight warming in the past century, much of it was neither human-induced nor geographically uniform.

[CharacterCounts]

I wasted my time trying to explain the difference between causation and commonality to a friend of a friend who was prattling on about how we are cooking ourselves.

Its okay that your friend cannot rcognize the difference between causation and commonality. Its a terrible thing when so called scientists such as David Suzuki refuse to acknowledge the difference. She is merely ignorant. He knows better and that makes him a fraud.

[TruthShallSetYouFree]

Industrial and energy emissions have increased the atmospheric concentration of CO2 by about 80 ppm since 1850 or so. This increase in the concentration of a gas that absorbs infrared radiation alters the Earth's radiative balance, and this alteration affects the global climate.

By how much?

[Dixie Yooper]

2.7 degrees is not an estimate.

[cogitator]

2.7 degrees is not an estimate.

It might be accurate; there is a good amount of ice core data from Greenland.

[cogitator]

By how much?

The direct effect of a doubling of CO2 concentration is about 0.9 degrees C of warming. Climate feedbacks are expected to augment this. These feedbacks (as well as they are understood, and some, particularly clouds, are not understood very well) are what leads to the IPCC estimate of 1.5 to 4.5 degrees C of warming by 2100. I don't think that the IPCC projects doubled CO2 by 2100, but 450-500 ppm is certainly quite possible.

[jguns]

(1)There has been tremendous worldwide industrial growth in the past century, and, (2)The average temperature worldwide has increased in that time period. The fallacy is in asserting, with no real proof, that the first fact is a major cause of the second."

I will take this further by pointing out that the warming trend started BEFORE industrialization and also that it rose at the same rate afterward as it did before. Thus, those two points are immediately neutralized if one is asserting them as a causal link.