Razza -- the point is that "Global Warming" is a bad name for it anyway -- the proper and correct term is "Climate Change", which basically means the obvious: that human-induced changes such as large-scale deforestation, burning of huge carbon stores that were otherwise locked away, introducing and breeding species such as cows whose CO2 and Methane emissions are sizeable, and inventing chemicals such as CFCs -- that all of these changes, together, are going to mess up delicately-balanced natural cycles. That can lead in the short term to an overall warming effect, but can also legitimately lead to Ice Ages too. For example, by disrupting the Gulf Stream that warms Western Europe, and so on.
The idea that humans have no effect on our planet is, frankly, ridiculous. You can see it in all sorts of ways such as those mentioned above, and many, many more.