You can disagree all you want, but that doesn't mean that [fill in the blank] is wrong. Bring something to the table other than "scientists are making up stuff, my 6th grade science teacher told me _____, there is not 100% perfect consensus on _______, I know nothing about it therefore it's wrong" and the like and I'll listen to you all day long. Taking quantitative measurements on something is not "opinion." You're using the word "theory" as if you're talking about the existence of Nessie. A theory for actual scientists is the explanation of natural phenomenon based on the best observations, measurements, etc. that we can make. Theories are refined as we get better observations, measurements, etc. CO2 dramatically increasing is not an opinion or theory, it's a observation.