It appears that there are many more scientists who think our civilisation is heating our planet up more than would have been the case otherwise than there are qualified people thinking otherwise, and I therefore do think it’s foolish to avoid taking strong measures to combat global warming.
However, as the recent Copenhagen summit showed, the evidence is not yet so overwhelming that all of humanity can be convinced, and it’s therefore very hard to achieve any meaningful emission cuts.
We therefore need to get more evidence and refute all major competing theories.
One of the alternative favourite theories cited by the opponents of global warming is solar activity.
I therefore found this article (written before the current cold spell began) very interesting:
But how to prove this? During the 20th century, solar activity rose steadily, as did the amount of industrial gases being pumped into the atmosphere. With both quantities rising, it has been impossible to distinguish between them. Now, that has all changed.
In the past 12 months solar activity has fallen to levels unseen since the 1920s. Sunspots have become rare sights and for three quarters of this year the Sun has been spot-free. According to one study if the trend continues at its current rate, the Sun will lose its ability to produce sunspots by 2015. That would take it back to its condition in the latter 17th century, when hardly any sunspots appeared for 70 years — and Northern Europe underwent the worst years of the so-called Little Ice Age.
Winter scenes from this period were romanticised by artists such as Brueghel painting frost fairs and hunting scenes. But was the 17th century sunspot crash responsible for the Little Ice Age or a coincidence? Could we now find ourselves plunged into a similar freeze if the sunspots do not return?
I’m well aware that the current cold spell doesn’t disprove global warming in the slightest. One possible consequence of global warming could be the Gulf Stream moving or stopping completely, and that would make the British Isles even colder than they are at the moment.
It will be interesting to see if the solar activity theory can be complete refuted within a few years, though.