The problem with the climate change debate is that generally you can't have a meaningful discussion about it, there is such a deep divide between people who believe in man made climate change and those who don't that to anyone in the middle it's like observing two religious cults blindly chanting their mantra in an attempt to drown out the other, and both come over as rather extremist.
You have one group which denies the most remote possibility that climate change could occur as a result of human behaviour, even on a conceptual level and another that attributes every freak weather event, every warm day in February, as a sign of the impending apocalypse. Frankly, people are sick of hearing about it because most sensible people can see how stupid both positions are.
Now I myself am a believer in man made climate change but I base that on my own assessment of the evidence available. There has been a spike in global temperatures that have mirrored a spike in CO2 emissions and even on a logical level, we are pumping millions of tonnes of C02 into the atmosphere, altering it's composition, it would be odd if it didn't have an impact to one degree or another.
However, while I do believe human activity is having an impact on the Earth's climate, I am not confident that climate change as we are experiencing it is the result solely of said activity. We have to remember that we have been recording weather and climate conditions in sufficient detail to be valid scientific evidence for a few decades now and while we can obtain additional evidence (such as from polar ice) there is still a huge amount we just don't know. In addition there are longer term climate trends which we do not fully understand which complicates the process of drawing a baseline from which to extrapolate the degree to which the actual temperature is an aberration from the expected level.
Well, the counter point is that we don't have any real idea what the natural climate trend for earth is when looking at the passage of millions of years. We know for example that the climate of earth has been radically different several times in it's billions of years of history, ranging to the steaming jungles of the dinosaurs, to the ice age that wiped them out. People assume there were other factors and try and find evidence of a meteor collision that could have cause an ice age, with mixed results (none are universally accepted, and it remains a theory). One point that's been made is that the earth doesn't follow as predictable a rotation about the sun as we once thought, rather it spirals in closer and then further as part of it's orbit, albeit very slowly, with many, many, years in between. It's theorized by some that the climate change we're seeing is natural, and that if humanity remains around due to our technology we'll see
the world go through cycles of both incredible heat, and massive ice ages. Another similar point being made that's connected to this is that earth is actually overdo for an ice age, and that following the patterns we should be getting colder, not hotter, the CO2 gasses and things that we've been using are actually responsible for the survival of humanity at this point because we've been able to trap the heat down here on earth and prevent massive climate change in the other direction. According to this theory while we might stand to lessen things up a bit for comfort reasons, actually cutting our CO2 emissions and doing the things that guys like Al Gore wants would probably doom humanity
but radically dropping the global temperature and perhaps bringing about another ice age, as it's debatable whether
we could ever recreate the same events once all the heat we're trapping is gone. We don't yet have the technology to be able to survive a full on ice age, or at least not dispersed widely enough for human civilization to continue as it is.
My basic attitude is that there are a lot of theories when you get down to it, the whole "Global Warming" thing is largely a political construct as it exists now. *IF* it actually exists, and if humans are actually doing it, there is then the question as to whether we really want to radically change it. There are climate scientists that point to the overdue ice ages and say "it's happened already, and greenhouse gasses have saved us" for example, and I'm not quite ready to dismiss those kinds of points. As I mentioned in my last post Larry Niven's "Fallen Angels" touched on a lot of the less politicized environmental issues related to climate change. While I won't take it as gospel it did convince me that it's something we don't want to jump on without a lot more information than we currently possess. What's more the fact that it's political should make people wary even if they agree with the overall intent, global warming as an issue largely exists to attack industries that the left wing isn't allied with, for the benefit of ones that it is.