2017 prolly second hottest year ever

2016 was the hottest year ever measured.  It was  an El Niño year, as 1998 was.  But this time round global temperatures haven't fallen as they did in 1999.

Source: RealClimate.org

Note how the denialists got to say that (before the most recent jump) global temperatures hadn't risen for 16 years.  They chose 1998, an El Niño year, as the starting point.  Naturally, if you chose a high point as your start, then the rise over the next few years is low.  But if you take that El Niño year and compare it with the most recent El Niño year (2016) temperatures have risen by 0.4 degrees C.  That's 0.22 deg C per decade.   To my eye, the upward trend in this chart has clearly accelerated.  The folks at RealClimate would say that I don't have enough evidence, and they'd be right.  Yet policy makers have to deal with credible and likely risks.  They can't wait another 20 years to be sure that the trend has accelerated.  Anyway, it was bad enough before--0.17 deg C increase per decade.  We need to start rolling out renewables now.  As fast as we can.  Or faster.

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