Global warming will offset big freeze
Global warming is now so great that it will largely offset any cooling from the Sun
Spring eclipse as viewed from the Solar Dynamics Observatory
The Sun may be slipping into a prolonged depression last seen 300 years ago, when brutally cold winters led to social upheavals across northern Europe.
However, a study just published by British and American scientists has found that if another grand solar minimum does happen the effects on climate will be different because global warming is now so great that it will largely offset any cooling from the Sun.
Across the world, the researchers found that weak solar activity would have a negligible effect on temperatures. However, temperatures in eastern US, UK and northern Europe would drop in winter by up to 0.8C. This cooling would be largely offset by global warming, which is expected to raise temperatures by 2C in the coming century. For the UK, this means that winters are predicted to continue to be largely mild but not as warm as previously thought, although the odd severely cold winter could still happen.
“The risk of cold winters is substantially reduced because of global warming, despite the grand solar minimum,” said Sarah Ineson at the Met Office. “Climate change is so large that the warming will carry on regardless.”
The effect of the Sun’s downturn on the UK is thanks to the influence of the jet stream on our climate. Weaker solar activity cools the top of the stratosphere 50km (31 miles) high, and this cooling burrows down and weakens the jet stream, leading to cold easterly winds sweeping into the UK from Europe in the winter.
The last “grand solar minimum” happened from about 1645 to 1715, a period known as the Maunder Minimum, when sunspots vanished from the Sun’s surface and led to some brutally cold winters across much of North America and northern Europe.
Conditions grew so grim that crops failed, food prices soared, riots broke out and famine was widespread. The 1690s were particularly dire times in Scotland, where famine and disease led to mass migration to North America.
In London, frost fairs were held on the frozen Thames and in northern Europe glaciers grew larger. This was also a time of virulent witch-hunts as scapegoats were sought for the freezing weather.
http://www.thetimes.co.uk/tto/science/a ... 478212.ece
