Pokenator said:
There are no 'opinions/theories' among the vast majority of mainstream scientists, there are only facts and evidence which all points in the same direction. The only debate is the magnitude of the effects. Ironically, the actual effects we're feeling are following the worst-case scenario predicted by the scientists 10 years ago.
Actually, climate change denial, while it may be rejected by most scientists, is a valid position.
While it is certain the earth is heating up, I am not convinced Co2 emission are its cause. I have asked scientists and my teachers to show me the simulations that they claim will synch up with both what we saw in the past hundred years and what is projected in the future. Problem is, no scientist will show me the data. I then have asked them to show me the math they use to come up with their numbers. They won't show me that either. Now, I admit that this does not prove it is not happening, because they may just be believing it without looking at the math themselves, but I have trouble accepting a postulate on something as complex as climate without looking at the simulations myself. Saying that "Co2 emmisions are up, temperature is up, therefor Co2 emmisions cause global warming" is not logical, because you could just as well say "There is more plastic in the ocean now than 100 years ago, temperature is up, therefore plastic in the ocean is causing global warming" in other words, Correlation is NOT causation.
In addition, considering that almost all the evidence about global warming is gathered by computer simulations, it raises a big question mark over the validity of the method when you realize that computer sims are extremely inaccurate. My father's entire career is based around making computer simulations more accurate (specifically, weather sims for air force computers), and if such a field can take twenty people thirty years to work on and still be extremely error prone, then I cannot simply accept on trust alone that the results of computer simulations are automatically valid.
I also sometimes wonder if our science nowadays is really any better than science 30-40 years ago where there was increasing concern about whether the earth was going to have global cooling. I admit I was not alive then, but my parents have told me there was a huge media fevor about us possibly going into another ice age. Now, the scientific method has not changed (as far as I know) that much in 30 years, but the scientific opinion has, so I am not sure if the data we have now is any better than the data we had 30 years ago.
Also, there is so much mud-slinging on both sides of the climate change debate, that I don't know who to believe. The people who say climate change is caused by Co2 say the ones who say otherwise are paid off by the oil companies, while the ones who say climate change is not caused by Co2 say the others are working from inaccurate data. I cannot value one opinion over the other without hardcore evidence that the corralation is valid, but since neither side will show me their core data, I cannot say with any degree of certainty one way or the other.
TLDR version: I am not convince that global warming is caused by humans, because both sides claim the other aide has faulty data