I am indebted to Dr Jarl Ahlbeck, from Abo Akademi University, Finland, who contacted me about his fascinating new piece of research relating to this winters severe cold across much of Europe, and a possible link to the very low solar activity we have been experiencing.
I am aware that there is a hugely varied readership of my blog; those who are very well informed about weather and climate, and others that have an interest in the subject but would struggle with some of the details contained in scientific papers. I have thus asked the author to summarize the main points of the research, and will include a link to the paper for those that feel brave enough to look into it themselves.
Dr Ahlbeck writes:
Historically, low solar activity periods like the Dalton and Maunder Minima have been connected to cold winters in Europe. It seems very possible that the low solar activity forced areas of low pressures into a southern route or caused a negative Arctic Oscillation, AO, which in turn allowed cold air from the North Pole to flow across Europe. But can we obtain from real measurements that low solar activity really is able to do that?
I found that the mechanism is statistically significant, but it is not very simple to prove. There is no direct statistical relationship saying that low solar activity always should cause a negative Arctic Oscillation (which caused cold air to push further south than normal). But if we consider a second natural parameter, the strength and direction of the stratospheric wind in the Tropics (the Quasi-Biennial Oscillation index, QBO) I found a very interesting result: During periods of low solar activity (few or no sunspots) an easterly QBO causes a negative AO, but a westerly QBO causes a positive AO.
However, during low solar activity the easterly QBO causes a considerably stronger negative AO than the westerly QBO is able to cause a positive AO. Furthermore, easterly QBO is more common than westerly QBO during the Nordic Hemisphere winter.
The conclusion of my work is clear. If the sun goes into a new Dalton and Maunder minimum, we can therefore expect extremely cold winters in North America, Europe and Russia – which is exactly what was experienced during both the Maunder minimum (1600’s) and the Dalton minimum (early 1800’s).”