Who would have thought that if you knew the air pressure in Darwin and Tahiti in June, you could figure out that the start of 2011 might be a Stalingrad Winter up North and a cooler wetter summer down south (Not that people in Sydney feel all that cool right now). But the air pressure ratios are reported as the SOI (Southern Oscillation Index) and it’s the handiest thing if you like predicting global temperatures 7 months ahead. Look at that correlation.
Since June last year Bryan Leyland has been using the simple connection described by Carter, De Freitas, and McLean in 2009 to predict up and coming temperatures.
So far, for what it’s worth, he’s right on track.
Such is the power of the stored pool of cold that is the bottom three-quarters of the Pacific Ocean. And when you look at how vast the Southern Pacific ocean is, is it any wonder it has such an influence? All that heat capacity…
Back on August 6, 2010, when the UK BOM was predicting a warm winter, and every Met Agency in the West was already declaring that 2010 would be the hottest year ever, Bryan Leyland predicted (on a global scale) that before the end of the year, there would be significant cooling. As you can see from the chart, this is exactly what happened.
The UK Met Office has a gigantic supercomputer, 1,500 staff and a £170m-a-year budget, but a retired engineer in New Zealand armed only with Excel and access to the internet and with the McLean is et al 2009 paper, was able to get it right.
Parking the SOI index (the blue line) 7 months into the future suggests things may get cooler still as the temperature (red line) often follows the trend. (Click for a larger image.) Note, the SOI is shifted 7 months forwards in time, and the scale is inverted.
Before anyone scoffs that the El Nino’s are usually followed by cooling, and the SOI indicator is well known, ponder that the well fed agencies of man-made-climate-fame weren’t telling the public that a big-chill was on the way and they ought to stock up [...]
Guest Post by Bryan Leyland El Nino/La Nina effect (SOI) predicts global cooling by the end of 2010
A July 2009 paper by McLean, de Freitas and Carter showed that global average temperatures followed the Southern Oscillation Index (El Nino/La Nina) with a 5-8 months lag. The graph below shows that when the SOI is shifted forward by 7 months the two plots change direction together (except when volcanic eruptions caused cooling).
The chart above shows a projection of temperatures to Feb 2011. The chances are that the present warm spell will end quite suddenly before the end of this year. Over the next few months the SOI will indicate whether or not the cooling will continue beyond Feb 2011. Evidence from studies on past climate and sunspot cycle related effects gives a strong indication that the cooling will continue.