A friend said to me "I can't comment on climate change as I am not a scientist."
I said "Well I can because I am a scientist."
He said "What? You're not a scientist!"
I said "Yes I am. I have a B in GCSE Physics and I can tell you that if you put Carbon Dioxide into the atmosphere it will warm the atmosphere. That is what we are doing in exponentially increasing amounts so the atmosphere is warming on a very large scale.
I can also tell you that if you warm the atmosphere it will rain."