2014 was the hottest year on record. 2015 is the hottest year on record. January, February & March were the three hottest months on record (with December 2015 now number 4). 2016 will be the hottest year on record. Yes, climate change is progressing neatly.

Two days ago we showed the global temperature dataset of JMA, which indicated March 2016 was the hottest month ever recorded. Here we show the temperature graph of NASA GISS, which indicates March was the second hottest (+1.65 degrees Celsius above the 1951-1980 average) to February, meaning this peak still stands (In NASA GISS February was +1.71 degrees above that baseline). All in all we’ve seen a full-grown mountain range of global monthly temperature peaks, which started in 2015 and might well continue throughout the spring months of 2016. Altogether 2016 will break the ‘hottest year’ record of 2015. Graph by Stephan Okhuijsen, Datagraver.com.

We are not afraid to take/steal a little credit where it’s not easily given to – let’s face it – an obscure and just really rather small website (but still we hope one of your favourite bookmark pages for random climate science talk), Bitsofscience.org. Here goes:

A short history of temperature records

It was March 2014 and climate deniers were still saying ‘the world was cooling since 1998’ – cherry picking in the least-established global temperature datasets, like that clunky old graph the University of Alabama keeps updating [no offense, we also have a thermometer in my backyard – but graphing and posting it does not really contribute to science.] Better established datasets, like NOAA NCEP and NASA GISS, had already shown both 2005 and 2010 had broken the 1998 record. And the one-and-a-half decade temperature plateau had been explained through Chinese sulphur emissions and (strongly) ocean current cycles – not just ENSO (La Niña’s dominance), but also the Atlantic Meridional Overturning Circulation (AMOC).

Anyway, it was early 2014 and the year had made a relatively chilly start – see the dip in this graph – over the first three months. But for all those following the models, it had become clear a strong El Niño was developing in deeper waters – and that would break the then-existing plateau.

So on April 7 of that year we made a little forecast: 2014 and 2015 will be the two subsequent hottest years on record – which indeed they became. Now last year we added 2016 will break the record of 2015. And with three months in that has now become evidently clear too, even as El Niño will transition to La Niña somewhere in early summer: This heat is unprecedented.

Now what does this all say about the actual global temperature trend? We haven’t decided yet. But statistics say that peaks do indeed raise trends…

We’ll get back to that matter. Part 14 coming soon.

© Rolf Schuttenhelm | www.bitsofscience.org