Yesterday we took a look at what we have been doing over the past 40 years. Now we take a look at what we will be doing over the rest of the 21st century. It’s a real shocker to look at: All policy scenarios now require an immediate trend breach – this is the biggest challenge mankind has ever faced:
And now it has to go sharply down. To summarise the entire IPCC WG3 report on climate mitigation:
This is the graph of the world’s best-established temperature dataset, of NASA GISS. It shows another good representation of the 1997-1998 El Niño world average temperature peak.
Recent years have been net influenced by La Niña state, as shown in this graph – although also the 2005 and 2010 temperature records have been provoked by short/weak El Niño events, taking place in late 2004 and late 2009. From 2010 La Niña has dominated. This will change.
Shown below is a graph of the satellite-derived University of Alabama global temperature dataset (those fellows that each year in early January beat NOAA/NASA/MetOffice/WMO etc by being the first to say ‘how warm it was’). Clearly visible is the peak of the powerful 1997-1998 El Niño:
El Niño Southern Oscillation index: duration and intensity of La Niña and El Niño years. El Niño is usually defined as a positive temperature anomaly in the east and central tropical Pacific. Another way to express the climate phenomenon is through an index (Southern Oscillation index) for air pressure difference across the equatorial Pacific – with relatively high pressure in the West and low pressure (because of increased convection over warm water) in the East typical for El Niño. The above graph uses that alternative indicator – and it holds a clue to our temperature predictions for 2014 and 2015: hottest year on record, followed by the hottestest year on record…
If we take another look at the IRI ensemble forecast for El Niño some members show a clear and speedy rise in East Pacific tropical ocean temperatures. Before we conclude ‘El Niño ahead’ during northern hemisphere summer and autumn let’s not ignore that a handful* of the 23 climate models show only a weak increase in water temperatures, staying below the official El Niño threshold (+0.5C).
[*) We all know an average hand can hold around 7 climate models – which means some 70 percent of models say El Niño, whereas 30 percent says somewhat warmer (up to half a degree), but still neutral ENSO.]
Well then, is there any way of telling which of the climate models may be more inclined to predict actual climatic events for upcoming months? Yes, probably there is: