New calculations suggest more than one in ten chance of colder UK winters.
As the Sun enters a period of low solar activity over the next 50 years, new research has calculated the probability of unusually cold winter temperatures occurring in the UK.
Last year, the same group of researchers, from the University of Reading, linked colder winters in Europe to low solar activity and predicted that the Sun is moving into a particularly low period of activity, meaning the UK will experience more cold winters in the future – potentially similar to those experienced in the Maunder minimum at the end of the 17th century.
The new research, published today in Environmental Research Letters, supports recent suggestions that sunspot activity is waning, and goes further, using the behaviour of the Sun over the last 9300 years to predict the probabilities of future solar changes.
Over the next 50 years, the researchers show that the probability of the Sun returning to Maunder minimum conditions is about 10 per cent, raising the chances that the average winter temperature will fall below 2.5 oC to around 1 in 7, assuming all other factors, including man-made effects and El Niño, remain constant.
Put in context, the average UK winter temperature for the last 20 years has been 5.04 oC, however the last three winters have averaged 3.50 °C, 2.53 °C and 3.13 °C, with 2009/10 being the 14th coldest in the last 160 year
You can even read the official paper here.
So thats it then, climate change has been cancelled? No, not at all. No doubt climate change sceptcs will tout this as “evidence” against climate change, but its not. Now lets get one thing clear, in April 2010 a study published in the Proceedings of the National Academy of Sciences showed that nearly 98% of working climate scientists accept the evidence for human-induced climate change, this paper does not change that. The public might think that the proper scientific view is to be sceptical about climate change, or believe that scientists are “evenly divided”, but the reality is that it is very much accepted and there is general consensus regarding its reality among those who work on it.
So why the apparent conflict?
Well, it is because global climate change is concerned with average temperatures for all parts of the world and all times of year. This new paper focuses on changes that only apply in winter and are regional – for example, when the winter is colder in Europe it tends to be warmer in Greenland so that there is almost no effect on the global mean.
So what might be happening here?
One possible mechanism that suggests a link between the Sun and recent cold winters is ‘blocking’. Low solar activity causes extensive anticyclones that persist for several weeks in the Atlantic Ocean, causing the warm westerly winds to be replaced by cold, continental north-easterly winds. Depending on the position of the anticyclone, this can also lead to clear skies at night causing the land to cool even further.
Lead author Professor Mike Lockwood said,
“Our results show that over the next fifty years there is a 10 per cent chance that temperatures will return to Maunder minimum levels. Describing the Maunder minimum as a ‘little ice age’ is somewhat misleading however.
“Cold winters were indeed more common during the Maunder minimum but there were also some very warm ones between them, summers were not colder, and the drop in average temperatures was not nearly as great, nor as global, as during a real ice age.”