El Nino is an effect rather than a cause.
There are a lot of feedbacks that we haven't seen yet. We're only at +.87 degrees. Even +2 Degrees is a different ballgame, and we're talking more than that with RCP 8.5.
With the last two years added to the equation, I don't think AR5 is overestimating global warming. It's well within the error bars for the current emission levels, but it's too early to say at this stage. AR5 was the most conservative assessment report of the lot.
We have to work with the best resources available.
Have you heard of Admiral James Stockdale? He was the most senior US Officer to be captured by the Viet Cong, and went on to be the US Vice Admiral and later ran as Vice Presidential candidate to Ross Perot. A lot of what he said applies here.
Quote:Face the most brutal facts of your current reality and retain faith that you will prevail in the endgame
Optimism is fatal.
Quote:What the optimists failed to do was confront the reality of their situation. They preferred the ostrich approach, sticking their heads in the sand and hoping for the difficulties to go away. That self-delusion might have made it easier on them in the short-term, but when they were eventually forced to face reality, it had become too much and they couldn’t handle it.
http://www.ndoherty.com/stockdale-paradox/