As with all complex problems, we attempt to find simple answers. The chicken little's of global warming take the simple approach that we humans are to blame, and therefore, we humans can fix the problem. Rather egotistical in my opinion.
The parameters I measure this with began with high school and college science courses in the mid-70s -- that the earth's climate is changing and trending warmer. As the earth warms, the polar ice caps will melt, increasing the levels of our ocean and decreasing the land mass. The theory then was that this would serve to moderate warming, and eventually lower temperatures and perhaps even trigger an ice age. Since then we have become much more adept at measuring things -- and graduate students and scientists have probed ancient ice cores, tree rings, rocks, ocean sediment, etc. to measure miniscule and often mundane things. They continue to advance theories based on these new measurements, trying to make sense of a wealth of data points. Sometimes these data points connect, other times those manipulating the data try to pound that square peg into a round hole.
Good science works through trial and error, testing theories until they can be proven, and then moving on to solve the questions that arise in the process of answering the previous question. There has also been a growing trend to sensationalize the problems to attract funding, which opens the door for politics to dilute and distort science.
The trend is clear, the cause is not. And the outcome is equally unclear. There needs to be a lot more data gathered and verified, and theories validated. Doesn't mean we need to ignore the problem. But we need to be very aware of the agendas behind the power brokers in this global debate.
It is amazing how a long ride helps bring my thoughts into focus! [Have to keep some sort of biking link here, right?
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