Subject: [Tweeters] Man-made (or not) global climate change
Date: Jan 7 20:01:31 2011
From: Andrew McCormick - andy_mcc at hotmail.com












Hello Tweeters,

The sparring between Andy and Scott (neither of whom I've met) was fun, but some serious scientific investigation and a body of knowledge about our planet was brushed aside a little too lightly for me not to respond.

Scientific inquiry does indeed require openness to the possibility that a theory could be wrong. In fact, when a theory is shown to be wrong we move closer to the truth. Most scientists who study climate change are not speaking as advocates, although some have published their findings in the popular press and books, as many scientists do in many fields. And, some believe the situation is so serious it requires them to be advocates. Nevertheless, there is very little (about 5%) doubt among scientists that the contribution of human activity, namely the increase in carbon dioxide in the atmosphere, is the primary cause of the current rise in average global temperature. This has increased about 1.5 degrees Fahrenheit since the beginning of the industrial age around 1890. Predictions of further increase are based both on the geological record of past periods of increased carbon dioxide in the atmosphere and simultaneous rise in temperature, and on new data on the upward trend of carbon dioxide in our atmosphere. See James Hansen's Storms of my Grandchildren. Dr. Hansen is an atmospheric scientist for NASA. He and others predict an additional rise in average global temperature in the next 40 years of at least another 1.5 degrees F. This will happen with the carbon dioxide that is already in the atmosphere. We continue to add more every day.

There have been oscillations in the earth's temperature over the life of the planet but the record in geological history and data from ice cores indicates these oscillations have not led to catastrophic warming leading to extinctions. See Peter Ward's Under a Green Sky. Dr. Ward is a paleontologist at the UW and he discusses the causes of past extinctions. All of them result from increases in carbon dioxide in the atmosphere primarily from the melting of tundra and warming of the oceans leading to melting of frozen methane (the stuff that clogged the cap on the Deep Water Horizon gusher). Both of these phenomena are now underway on our planet again. See also Tim Flannery's The Weather Makers. Flannery is an evolutionary biologist from Australia and draws on data from a variety of sources in his presentation of the positive feedback loops which indicate that as the earth warms, the planet responds in ways that warm it even faster.

We face a conjoining of forces over the next 40-50 years that regardless of cause will strain the fabric of our civilization. Warming temperatures, melting glaciers which serve as water sources for billions of people, rising sea level forcing large scale migrations from the coasts, spreading desertification in the temperate zone, and an increase in global population rising toward 9 Billion people will stress people and wildlife nearly everywhere.

The planet Earth will survive whatever happens. It has survived before - long before humans populated the planet. The way humans live will have to change, probably a lot. Should we be concerned about climate change? Undoubtedly, yes. Can we predict the exact scenario? Probably not. Will it come all at once? No. Will current trends continue? Yes, as long as the level of carbon dioxide in the atmosphere stays the same. If it increases, the changes will likely come faster.

Andy McCormick
Bellevue, WA