“25 percent chance” of Grand Solar Minimum
November 3, 2013
More speculation about slowing solar activity.
I created the above video in 2012 as an all purpose rebuttal to this perennial denial favorite. The paradox is that, depending on the denier, and the time of day, you may hear – “Of course it’s getting warmer – it’s the sun stupid!” – but in recent months when the “no warming in 16 years” meme has been in vogue, you may have heard the opposite, never mind that 2010 was the warmest on record, in the pits of the most recent solar minimum.
Mike Lockwood is a solar physicist who became a target of climate deniers several years ago when he wrote one of the definitive papers debunking the “it’s all caused by the sun” canard.
Now check and see if this latest interview with him becomes some kind of teapot tempest among the usual suspects.
Watch for this to be spun – I am sure that Dr. Lockwood’s “don’t look for a little ice age” disclaimer’s below show that he is aware of how the game works. (see video above for an example of denialist standard O.P.)
The sun’s activity is in free fall, according to a leading space physicist. But don’t expect a little ice age. “Solar activity is declining very fast at the moment,” Mike Lockwood, professor of space environmental physics at Reading University, UK, told New Scientist. “We estimate faster than at any time in the last 9300 years.”
Lockwood and his colleagues are reassessing the chances of this decline continuing over decades to become the first “grand solar minimum” for four centuries. During a grand minimum the normal 11-year solar cycle is suppressed and the sun has virtually no sunspots for several decades. This summer should have seen a peak in the number of sunspots, but it didn’t happen.
Lockwood thinks there is now a 25 per cent chance of a repetition of the last grand minimum, the late 17th century Maunder Minimum, when there were no sunspots for 70 years. Two years ago, Lockwood put the chances of this happening at less than 10 per cent (Journal of Geophysical Research, DOI:10.1029/2011JD017013).
Little ice age
The Maunder Minimum coincided with the worst European winters of the little ice age, a period lasting centuries when several regions around the globe experienced unusual cooling. Tree ring studies suggest it cooled the northern hemisphere by up to 0.4 °C.
But Lockwood says we should not expect a new grand minimum to bring on a new little ice age. Human-induced global warming, he says, is already a more important force in global temperatures than even major solar cycles. Temperatures have risen by 0.85 °C since 1880, with more expected, according to the most recent assessment of the Intergovernmental Panel on Climate Change.
This piece will be particularly subject to distortion, I am sure.
There may still be noticeable consequences. For instance, long term cold winters in the UK are common when solar activity is low. And less solar activity can slow the jet stream, triggering a suite of interlinked extreme weather events like the Russian heatwave of 2010, and the devastating floods in Pakistan that same year.
The takeaway: the well known 11 year cycles of solar irradiance and sunspots have very minimal effect on global temps because of the ocean’s thermal inertia. We may in fact be due for a “grand solar minimum”, such as was observed during part of the “Little Ice Age” – but such a minimum would be a very small forcing compared to the buildup of greenhouse gases, and would, at best, offset less than a decade of temperature rise.
I made the video below in 2010 summarizing the paradox in that year, – low solar activity and high global temps. With denialists, what’s old is ever new again.