Every single climate model predicted steadily rising temperatures for the last 18 years but even climate nuts admit the temperature has stayed constant.
The way science works is the following:
1) We make a guess about why something works the way it does
2) We create models or formulas that predict how things should behave if our guess is right
3) We compare those predictions to data:
a) If the predictions match the data we have reason to believe our guess is right
b) If the predictions don't match the data we know our guess was wrong
Here's what the models for man made global warming predict vs what we see
AS OF NOW THERE IS NO SCIENTIFIC BASIS FOR SAYING MAN IS RESPONSIBLE FOR CLIMATE CHANGE
Last summer some folks wrote a paper claiming the earth has in fact warmed in the last 18 years. Aside from the fact it only addressed one set of temperature measurements and other sets of measurements show that temperatures haven't gone up there are other huge problems with the study:
1) The study is basically saying that for more than 18 years all the same climate scientists who we are supposed to now trust have gotten the temperature records all wrong. Apparently now they are new and improved scientists.
2) The "fix" to the data essentially lowers all measurements before 18 years ago and raises all temperatures after 18 years ago. The chance that honest calibration errors would result in such a fortuitous situation just before a major climate conference is vanishingly small
3) The authors of the paper have a direct financial and career interest in keeping the global warming scare alive; no climate change fears and the funding for climate scientists falls through the floor.
One last note; the man who gave a speech in Paris saying that mass shootings like the one in Colorado only happen in the US also says that the climate change is real and that it's the cause of Islamic terrorism.