See here's the thing, though.  Why can they tell us with exact certainty that this is occurring, but can't tell us if it will rain next week?  Not probability, but certainty.  Not forecast, but prediction?  That's my main point.  Al Gore made a TON of money off of this and so did others.  None...zero...nada of his predictions in his first movie were true.  Is that supposed to convince me that a warming trend is occurring, "just trust me." ?  No can brah.  Plus too, the records don't go back far enough to draw definitive data, just a trend.  I study trends for a living, so data is key.  If the data is skewed to fit a particular viewpoint, I throw it out.  Whether beneficial to me or not.  Suspect info, even partially right, I scrutinize.  If it starts to not add up, then I rate it accordingly.