'The definition of "good science" can't be "scientists who tell me what I want to hear."'
I like this, I like this very much, anyone who considers themselves to be a scientist should always check the possibilities that they do not like. especially if these possibilities, go against a person's beleifes or positions. it is at the core of science to be be critical of what you hold most dear, this is science's true streigth, the ability to turn on a dime and abandon old theories when the evidence does not support them. so it does sadden, and in fact unsettle me to see that politics have managed to make man kind's greatest achievement, turn in on it'self.
when ever this subject gets brought up, the question it's self is almost never addressed directly. many people have what I guess you could call a misguided sense of responsibility which makes it easy for them to perceive human causes for damage when only circumstantial evidence points to it. having been raised by people who were among the first humans to realize the finite nature of the planet. children of solders in a cultural war between those who did not see or perhaps care about the consequences of there actions, and those who realised that humanity does have the ability to bring about great damage to the earth. anger ran deep and the battle was hard fought, but in the end the war was won, it is now believed that teaching our children about responsible management of our worlds limited resources is as important as teaching them how to get along with other people, or make a living for themselves. there is now an entire generation of people who, possibly for the first time understand how important caring for the earth is, an whole generation who know there is only so much coal, that forests take many years to regrow, and understand about how dumping poison into a stream will eventually filter back to them. as a triumph of science, countless melenia of harmful superstition and tradition like clear cutting forests and stream dumping were overthoughen in just a few short decades.
but unfortunately this triumph is short lived, because science is a creation of man, but not his natural state. now adults, these people perceive anyone who descents against any of the established ills humanity has wrought upon the earth as the enemy, the enemy who denies the obvius harm he is doing either out of ignorance or greed. much as generations of Greeks were told tales of Leonidas and the Persians, this generation grew up listening to captain planet versus the forces of pollution and human greed, unwilling to allow the hard fought battles of there parents to be lost they are quick to attack anyone who sounds like they might be trying to form an argument for shrugging off shepherding earth responsibly in favor a lazier greedier path. it is I suppose a better way than the one we had before, but I think there is still room for improvement.
so by this point you may be wondering what this has to do with global warming. well, it should have nothing to do with it, but unfortunately it has everything to do with it. if I ask the question "are humans responsible for global warming" I can not expect anyone to give me an unbiased answer, in fact I can hardly expect a scientific answer at all. before anyone looks at the data behind it they start looking up the potential consequences, and I'll get an answer like "what if we do nothing?". well that's a fine way to live as a general rule, you are concerned about to consequences of your actions, but it does not answer the question, 'are we to blame?'. specifically for THIS one, it's an isolated question, there are enough reasons to cut back on emissions a thousand times over. like you, I don't want dioxin in my water, I don't want mercury in my fish, I don't want acid in my rain, and I am quite happy with the thought of ozone layer's continued existence. but unlike many of you, I am unconvinced that the global warming that is happening is caused in great effect as result of mankind's industrialization.
now, this may anger or upset many of you. you are thinking what sort of an idiot can I be? carbon dioxide, as a green house gas, retains heat and humans are producing a **** ton of it, how can this not be effecting the earth? well first off I did not say it wasn't having an effect I just don't think it is as profound as you do, but more importantly, I think you have a misunderstanding about the stage that the temperature of the earth is standing on.
years ago, I accepted this line of thought, the earth is getting hotter, we are makeing stuff that can make it hotter, therefore we are responsible for the earth getting hotter. but then I started seeing the history of earth's climate. ice cores give about half a million years worth of information. if you go back about 12,000 years you see the earth is a much colder place, the graph between then and now is quite dramatic in fact, but this is before humans began to do anything significant. if you go further, you will find temperatures gradually get warmer and warmer until they are even hotter than they are now, then it suddenly falls out again. scale the scope back to a few hundred thousand years and a pattern seems to emerge, there is a sudden warming period followed by long periods of cold. we seem to be in one of the warming periods. interestingly the other warming periods all seem to be a bit warmer. using deep sea sediment cores, global temperatures for the last five million years have been calculated, these are much more interesting, in addition to the wild variations caused by the glacial cycle there is a clear trend the further back in time you go, the warmer it gets. even more interesting is radiometric measurements have been used to gauge a rough estimate of temperatures back as far as the dinosaurs, the measurements show earth is in a historically cold period right now, once you go back more than five million years today's temperatures are about as cold as it could get, the earth was 12 degrees hotter 50 million years ago than it is now, extending this technique out to the last 500 million years shows a number of ice ages, and it looks like we may be coming to the end of one right now.
of course, the issue isn't simply about the earth getting hotter, it's about humans causing the earth to get hotter, the atmospheric content of carbon dioxide is about 800 billion tons IIRC, and humans are believed to be responsible for about half of that. sence we have doubled the amount of CO2 in the air in 200 years, and the temperature has shot up it seems that there is a causal relationship here, but is it? the temperature has been shooting up for a long time, it only stumbled a little over the last thousand years ago, as the temperature got warmer humans boomed, our crops grew, our cattle flourish, and we had time to tinker with machines. the fact that we hit the industrial revolution just as the earth started warming up isn't totally coincidence, had the little ice age continued, I doubt we would have developed the technology we did or at least as fast as we did.
but disregarding that for a moment, we are currently responsible for fully half the CO2 in the air, that should count for something, right? well it is undoubtedly causing some additional warming, but CO2 as it is currently, only represents less than half of one tenth of one percent of the atmosphere, and it's not even that strong of a greenhouse gas, water vapor for example is far more effective and far more abundant, CO2 is only responsible for 6% of the greenhouse effect, and CO2 is at historically low concentrations. wait, what's that? you don't believe me? isotopic ratio analysis has consistently shown that CO2 levels have been almost unanimously higher than they are now, during the time of the dinosaurs, it was 10 times as high, before that it was as high as 30 times the current concentration, if you look at the timelines you will see some of these high concentrations correlated with ice ages, so even if CO2 wasn't at all time lows, it still is clearly not a dominant green house gas.
now all of this does not prove anything, but it does give me some perspective. we know that the green house gases we are emitting are capable of retaining heat, but they make up a fairly small percentage of our atmosphere, the effects that our portion have I do not believe represent something unprecidented in earth's history. and the more I look at longer term temperatures the less I see us causing major changes. even if you go by the wildest projections the temperatures are still well within earth's long term norm.
and with this mighty blast of text typed after inq's post without reading anything that has happened since, I enter the frey.