However I don't know why there is controversy over the existence of hiatus if even the IPCC 2013 report accepts it as existing and spends a few pages (Ch. 9) discussing it.
Science moves on... are you suggesting that just because it was in the IPCC report the matter is fully settled and over with? Even though I agree with the conclusions of the IPCC report, I'm sure there are many things in the report which will have to be revised in the future.
Just like gjm, I think you're confusing existence and interpretation.
Outside of political posturing, I don't know why someone would claim that hiatus as a feature of the historical data set does not exist. It does and it's pretty clear. That's existence. What does the hiatus mean is a different and a much more complicated question. You can claim it's just an artifact of random variation. You can claim it reflects multi-year cycles in global climate patterns. You can claim it shows that our models are deficient and we don't understand climate variation. You can claim many things -- but a claim that the hiatus just does not exist doesn't seem reasonable to me.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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