Dear Noel, Felix, and WeatherCat climate watchers,
I think you'll find your argument has proved to be incorrect may times. I'm not a scientist and can only rely on what those more wise publish so I have to point you to here for a full explanation:
I fully agree with you that there is a lot of scientific claims that we have a very precise understanding of the climate. My points though allow for most of this research to stand completely unchallenged and still nonetheless dismiss the claim that we have proven a causal link between human produced CO
2. I'm not contesting at all for example that we are seeing alarming reductions in polar ice. That research is beyond reproach. My counterpoint is simply we cannot be certain that such rapid ice loss has never happened in a similar manner at some other point in the Earth's history. We understand the glaciers we can study today, but we don't have nearly the same level of understanding of previous rapid reductions of glacial ice. The geological record shows it can happen very rapidly - we don't have the precision data to determine exactly how rapidly.
The same point applies about observations of climate in general. Reliable thermometers have only existed for about 200 years, never mind all the rest of the meteorological instruments we count on to make very precise determinations of climate change. It is beyond doubt, the
Little Ice Age of the dark ages was much more extreme than any climatic features we are observing. Without the same sort of precise measurements, how can we rule out that the changes we are observing now are not a result of some natural feature that humankind encountered before the invention of weather instruments?
That leaves one possible means for arguing that climate change is purely and simply a result of human produced CO
2 - a causal model that is capable of make accurate predictions into the future. It is on this matter that I declare checkmate.
The physics of greenhouse gases is well understood. We have had climate computer models for at least 25 years. For at least that long, researchers have been trying to make predictions based on our understanding of greenhouse gases and -
failing. The study I cited at the beginning of this thread is a perfect example of that. The rapid depletion of polar ice means the heat sink that the arctic represents is getting less capable of cooling the jet stream in wintertime. That should make it impossible for the harsh winters that occurred in the American Midwest and Atlantic seaboard.
Oops, that impossibility happened anyway.
But wait, the news gets only worse on the prediction front. California is in the middle of its second year of drought. Last fall, I watched carefully the forecasts of the National Weather Service's Climate Prediction Center:
http://www.cpc.ncep.noaa.gov/Throughout autumn the forecast was for normal rainfall. Instead the drought continued. About a month ago, I started this thread announcing that the Climate Prediction Center had announced a hotter than normal summer for regions in the United States including Northern California:
http://athena.trixology.com/index.php?topic=1255.0We are closing in on a month and their predictions are thus far incorrect. Temperatures are running normal - not above normal.
Without a rigorous predicative model demonstrating a causal link between CO
2 emissions and the current climate situation, we simply cannot be certain that CO
2 is the
ONLY cause. The intuition that it is a contributor is perfectly reasonable. However, if other climatic changes are afoot, we could invest enormous amounts of money in the wrong directions and leave vast populations in grave danger.
The position I'm advancing is a very pessimistic middle-ground. It is definitely not a basis for complacency, but for action. Without causal models of how the climate is going to change, we cannot plan efficiently. For example, if we could have predicted the current on-going drought, people could have planned for the water shortfall. Instead, we find ourselves facing genuine climate change - but must plan for it effectively
"blind." We have very little idea of how the climate will actually change and should take precautions based on the most prudent expectations.
As an example of where we stand, consider California's drought situation. As I wrote in another posting, the 1976-77 drought in California brought the state almost to its knees. At the time there were only 20 million people in the state. Since then, between conservation and reservoir building we have effectively about a 25% additional reserve. However, the state population is almost doubled. Tree ring data indicates that decades long drought episodes have occurred several times in only the last 1000 years - without any human pollution to further destabilize the climate. What would happen to California if we are headed for a decade long drought? California is one of the top 10 economies in the world, can the globe afford to allow California to become a desert? In those past 1000 years, great cities in South American were abandoned because of drought. Can the United States (or the world) afford to evacuate the San Francisco, San Diego, and Los Angeles metropolitan areas if there isn't enough water to sustain the millions living there?
In a recent opinion poll, Californians expressed real concern over the current drought. Yet, the majority preferred conservation over expanding the existing water resources. What apparently escaped their attention is that cannot reduce our water use by over 90% to ride out a decade long drought. There is no way the state could operate on 1/10 the water is uses now.
So there is a climate-related potential disaster that could easily occur without any human induced climate instability. This scenario alone is likely to bring civilization to the bring of collapse, and of course, such a drought would not effect California alone. Yet, Californians are very determined to pursue green energy and conservation initiatives even if it is certain such efforts aren't sufficient to cope with previously observed climatic extremes.
This particular example isn't simply a demonstration of the gross negligence of political leaders. It is a damning condemnation of democracy itself. Never have we had a better educated populace. Never have people had better access to scientific information and tools make their own assessments of the threats facing our world. Yet, even as people are screaming
"the sky is falling" over global warming, Californians are "content" to play
Russian-roulette with La Nina related droughts. The trouble with Russian-roulette is that it isn't a matter of
"if" - but
"when."Sincerely, Edouard