There is increasing evidence to suggest that we may see an extreme El Niño event later this year, which could make 2015 the hottest year on record. Given that surface warming has slowed and we continue to accrue energy, most of which is going into the oceans, this seems like something that has to happen at some stage in the not too distant future. The oceans do have a large heat capacity, but they can’t accrue most of the excess energy for ever and – if our emissions are increasing the energy imbalance – they can’t accrue an ever increasing fraction of the excess. At some point surface warming will have to accelerate and a sudden large El Niño event is certainly one way in which this could happen.
I looked through some of my older posts to see if I had discussed this is any detail previously. I came across a post about Judith Curry and the Ocean Heat Content, in which I essentially made this argument. Judith was suggesting that the sequestration of energy in the oceans might be fortuitous, and I was suggesting that that really didn’t make sense as it couldn’t continue indefinitely and surface warming would eventually have to catch up.
So, if we do have a big El Niño later this year which leads to 2015 being the hottest year on record, and the subsequent decade being the hottest decade on record, maybe I (and many others) could say “told you so”. You’d like to think that all the naysayers would at least acknowledge that they were wrong and that the surface warming slowdown was simply natural variability, and not some indicator of reduced climate sensitivity. Of course, what will likely happen is that they’ll respond with suggestions that this shows that Bob Tisdale’s ENSO model is correct, proving that they really don’t understand radiative physics.
At that stage one could then show them the Escalator which illustrates that surface warming is actually quite variable, but that there is still a long term warming trend. Of course there are still those who think that the escalator proves their point, so sometimes their lack of understanding of radiative physics is so poor that they don’t even realise how little they understand. Anyway, it will be an interesting year. A big El Niño later this year would be one of those clouds with a silver lining. It might put paid to all the confusion that the surface warming slowdown has caused, but would also indicate that the lower climate sensitivities are less likely to be correct. It might be good for things to be more certain but what that implies is not something we should be pleased about. I’ll finish with the escalator graphic, as that seems apt.