Wednesday, 25 September 2013

The Prospects for Cooling in England and Around the Globe

With the IPCC just days away from releasing its mega report on the state of the world's climate and, by all accounts, set to reinforce the view that scientists are more confident than ever that humans are causing significant global warming despite the 15 year 'hiatus', with Ed Milliband claiming that he will force energy companies to freeze prices if Labour are elected at the next General Election, I thought it would be interesting and timely to take a look at the prospects for significant cooling, in England particularly and across the globe. 

So, whilst Ed aims firmly at the swing voters of Middle England, I thought I would take a look at what the UK's unique 350 year old data series tells us about temperatures in Central England. If, as I suspect, we are in for a significant drop in temperatures in our part of the world, particularly noticeable during winter, then energy prices are going to prove to be an extremely hot political potato in the next few years.

Firstly, let's take a look at what the Sun is doing. It cannot have escaped many people's notice - at least those who take an interest in climate change - that the Sun is in the midst of a lull in activity not seen for at least 100 years; by lull I mean lack of sunspots. We are near the middle of Solar Cycle 24 (SC24), having just passed maximum which was in fact the second max of a 'double peak' in activity, the first of which occurred in 2012. Sunspot numbers are around a half to a third of what they were during the comparable period in the early 1990's. 

SC25 is predicted to be even smaller still, with SC24 tracking fairly closely activity during Solar Cycle 5, which marked the decline in solar activity seen at the start of the 19th Century, now known as the Dalton Minimum. The Dalton Minimum lasted in Europe from about 1790 until 1830 and was responsible for a run of some pretty severe winters and lacklustre summers, though the oft quoted Year without a Summer of 1816 was largely due to a massive volcanic eruption. What is not absolutely certain is that, if SC25 turns out to be even smaller than predicted, we may be facing a downturn in activity reminiscent of the more severe Maunder Minimum which coincided with the so called Little Ice Age in Europe around 1645 - 1715. This useful little graphic illustrates the Maunder and Dalton Minima in relation to sunspot numbers.

By happy coincidence, the start of the Maunder Minimum in Europe is also very close to the beginning of the Central England Temperature data series maintained now by the UK Meteorological Office, the longest running continuous set of temperature measurements in existence. If we look at these figures, from 1660 until the present, what is immediately apparent is that there is a high correlation between central England temperatures and solar activity, with the Dalton and Maunder Minima and the late 20th Century Modern Maximum all very clearly discernible in the record.

Let us take some figures from these graphs, firstly for the 5 year running average annual temperatures:

Maunder                               7.8C

Dalton                                   8.3C
Modern Maximum             10.5C

What this tells us is that, if we allow only for external climate forcings due to solar activity, dismissing any supposed anthropogenic component for the time being, we can expect a drop in annual average temperature in England of about 2.2C for a decline in solar activity which mirrors the erstwhile Dalton Minimum and a steeper drop of 2.7C if we head into Maunder territory in the coming years. Note that internal climate variability (eg. ocean currents) must already be accounted for in the CET data series, so we need only look at external forcings and thus it is apparent that, if AGW turns out to be minor compared to solar and other natural variability, then, in the UK at least, we are headed for chilly times in the coming decades.

Just how chilly, on occasion, might be illustrated by further looking at the non-averaged figures for winter:

Maunder                         -1.1C      
Dalton                              0.3C
Modern Maximum        6.4C

In any particular winter, these figures mean a huge difference between a mild, relatively ice and snow free season, as we have generally come to expect since the 1980's, to something more akin to the winter of 1963, or even worse, not just on a one-off basis, but regularly. Even the averaged winter figures reveal a worrying trend:

Maunder                         1.8C

Dalton                             2.7C
Modern Maximum       5.3C

At the very least, we might expect winter temperatures on average to be 2.6C colder presuming no or negligible effect from anthropogenic CO2 warming. This will have a huge social, environmental and economic impact and is extremely concerning at a time when energy bills are at an all time high ironically because our government has put in place policies to mitigate the effects of a theoretically predicted catastrophic rise in temperatures due to AGW. 

So indeed, perhaps we in the UK and northern Europe had better hope that AGW is real and significant because it might be the only thing which saves us from freezing in the decades ahead!

What of the prospects for world temperatures and the global climate? Should we automatically expect a Maunder type solar event to impact upon the wider globe? There is evidence that the Little Ice Age was indeed a global event.  The UK government links global temperature with CET. Look at the plot of CET compared to global temperature provided in this link and it is immediately apparent that there is a strong correlation between the two, albeit that CET is more 'noisy' and appears to precede global temperature changes by several years quite often. So, on this empirical basis alone, we might expect to see a future significant drop in global temperatures. Average annual Central England temperatures have already declined markedly since 2009, falling more than half a degree in just 4 years. Worryingly, winter average temperatures have dropped 1.8C in that same period, shown here.

The increasingly urgent cries of the climate alarmists telling us that we need to be doing much more to limit carbon emissions to prevent imminent thermageddon look increasingly vapid, irrational and downright dangerous in the light of what has been said above. It is not sceptics who bear the heavy responsibility of leading the world into disaster; it is climate alarmists and the piggy-backing Green idealists promoting Agenda 21 type 'sustainability'.