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Real risk of a Maunder minimum 'Little Ice Age' says leading scientist

It’s known by climatologists as the ‘Little Ice Age’, a period in the 1600s when harsh winters across the UK and Europe were often severe.

The severe cold went hand in hand with an exceptionally inactive sun, and was called the Maunder solar minimum.

Now a leading scientist from Reading University has told me that the current rate of decline in solar activity is such that there’s a real risk of seeing a return of such conditions.

I’ve been to see Professor Mike Lockwood to take a look at the work he has been conducting into the possible link between solar activity and climate patterns.

According to Professor Lockwood the late 20th century was a period when the sun was unusually active and a so called ‘grand maximum’ occurred around 1985.

Since then the sun has been getting quieter.

By looking back at certain isotopes in ice cores, he has been able to determine how active the sun has been over thousands of years.

Following analysis of the data, Professor Lockwood believes solar activity is now falling more rapidly than at any time in the last 10,000 years.

He found 24 different occasions in the last 10,000 years when the sun was in exactly the same state as it is now - and the present decline is faster than any of those 24.

Based on his findings he’s raised the risk of a new Maunder minimum from less than 10% just a few years ago to 25-30%.

And a repeat of the Dalton solar minimum which occurred in the early 1800s, which also had its fair share of cold winters and poor summers, is, according to him, ‘more likely than not’ to happen.

He believes that we are already beginning to see a change in our climate - witness the colder winters and poor summers of recent years - and that over the next few decades there could be a slide to a new Maunder minimum.

It’s worth stressing that not every winter would be severe; nor would every summer be poor. But harsh winters and unsettled summers would become more frequent.

Professor Lockwood doesn’t hold back in his description of the potential impacts such a scenario would have in the UK.

He says such a change to our climate could have profound implications for energy policy and our transport infrastructure.

Although the biggest impact of such solar driven change would be regional, like here in the UK and across Europe, there would be global implications too.

According to research conducted by Michael Mann in 2001, a vociferous advocate of man-made global warming, the Maunder minimum of the 1600s was estimated to have shaved 0.3C to 0.4C from global temperatures.

It is worth stressing that most scientists believe long term global warming hasn’t gone away. Any global cooling caused by this natural phenomenon would ultimately be temporary, and if projections are correct, the long term warming caused by carbon dioxide and other greenhouse gases would eventually swamp this solar-driven cooling.

But should North Western Europe be heading for a new "little ice age", there could be far reaching political implications - not least because global temperatures may fall enough, albeit temporarily, to eliminate much of the warming which has occurred since the 1950s.

You can see more on Inside Out on Monday 28th October on BBC1, at 7.30pm.

END

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  • Comment number 183. Posted by newdwr54

    on 4 Nov 2013 09:41

    179. QuaesoVeritas

    "It would seem from what you say that it is increased wind speeds, not increased melt run-off, which is (according to this theory), that are actually extending the ice."

    There are two theories, both of which I referenced previously (#150)

    Basal melt from ice sheets and increased precipitation have made Antarctic surface waters colder and fresher, stratifying it above the warmer, saltier water underneath. Increased surface wind speeds have also spread the ice, causing it to ridge in some places and thin out in others.

    From a 'global warming' perspective, the main difference between Antarctic and the Arctic sea ice is the question of albedo, which only arise in the respective spring/summer periods. Spring and summer ice extent in the Antarctic (Sept-Nov/Dec-Feb) has increased at a rate of +0.12m/km2/dec over the past 30 years. Given that Antarctica is a snow covered continent, as a proportion of total albedo (i.e. amount of sunlight reflected), this increase is minimal.

    In the Arctic, the 30 year trend is -0.52m/km^2/dec. Since the Arctic is largely an ocean, this represents a huge net loss in albedo, and thus a huge increase in solar energy absorbed by the ocean.

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  • Comment number 182. Posted by 4caster

    on 4 Nov 2013 01:21

    Solar output may have been falling at a fast rate for the last few months, but the biggest mistake in the book is to extrapolate short-term trends indefinitely into the future. Solar energy reaching the earth has always fluctuated, within a range of less than 0.2 watts per sq metre in recent centuries, according to the IPCC. Man-made CO2 forcing amounts to 0.8 watts per sq metre, so solar variations are not going to stop warming of much of the globe. Read what Professor Lockwood has to say about it:
    "We should not expect a new grand minimum to bring on a new little ice age. Human-induced global warming 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."

    It is more likely that any reduction in solar activity will simply reduce the warming a little, and set us up for greater warming when it recedes.

    But any "little ice age" in western Europe will be a regional phenomenon caused by a weakened gulf stream/North Atlantic Drift and a slightly cooler ocean surface. It is quite compatible with continued warming throughout the rest of the globe. Not pleasant for us, but the long term threat remains that of warming.

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  • Comment number 181. Posted by ukpahonta

    on 3 Nov 2013 22:28

    Out of balance????
    A new equilibrium????
    Sea grows????

    Boy you need to stop smoking that stuff!

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  • Comment number 180. Posted by Picky Paul

    on 3 Nov 2013 20:02

    174.
    #QuaesoVeritas
    2nd November 2013 - 10:37
    "There are a number of reasons why warmer temps could result in more sea ice. "
    So, as long as temperatures continue to rise, so will the sea ice extent?

    No, what you have to remember is the global climate is out of balance, things will continue to change until we reach a new equilibrium, with temps more likely to be higher, than they are today rather than lower. Furthmore, regional differences are even more difficult to predict, for example whilst sea grows slightly in the south, it recedes rapidly in the north.

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  • Comment number 179. Posted by QuaesoVeritas

    on 3 Nov 2013 19:12

    #177.newdwr54

    "If the theories that i) there is an increased volume of freshwater run-off from the ice sheets during the Antarctic melt season; ii) this is stratifying near the surface above warmer but denser ocean water; and iii) the consequent increased winter sea ice extent is being blown further and more thinly across the surface by increasing wind speeds are right, then that seems likely."

    So is that the theory, i.e. that the extent is being made greater by increasing wind speeds?
    I had assumed that it was being pushed out by additional formation near the shore-line, otherwise it would just get thicker.
    It would seem from what you say that it is increased wind speeds, not increased melt run-off, which is (according to this theory), that are actually extending the ice.

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  • Comment number 178. Posted by ukpahonta

    on 2 Nov 2013 22:23

    “The findings support the view that the Holocene Thermal Maximum, the Medieval Warm Period, and the Little Ice Age were global events, and they provide a long-term perspective for evaluating the role of ocean heat content in various warming scenarios for the future.”
    http://judithcurry.com/2013/11/01/pacific-ocean-heat-content-for-the-past-10000-years/

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  • Comment number 177. Posted by newdwr54

    on 2 Nov 2013 15:03

    173. QuaesoVeritas

    "But October 2013 wasn't as warm as 1831 as it turns out! And July 2013 wasn't as warm as 1783, 1852, 1808 and 1757 either."

    That's quite right QV. Then again, 6 of the ten top 10 warmest October temperatures on the CET record, including the warmest one, have occurred in the past 20 years. July is certainly more spread out, but again, the warmest occurred in 2006, and during a period of very low sunspot numbers.

    174. QuaesoVeritas

    "So, as long as temperatures continue to rise, so will the sea ice extent?"

    If the theories that i) there is an increased volume of freshwater run-off from the ice sheets during the Antarctic melt season; ii) this is stratifying near the surface above warmer but denser ocean water; and iii) the consequent increased winter sea ice extent is being blown further and more thinly across the surface by increasing wind speeds are right, then that seems likely.

    Whether or not the increased albedo resulting from this acts to stall or even reverse the warming trend remains to be seen. I suppose that since we're mainly talking about autumn/winter extent increases, when sunlight levels are low anyway, it shouldn't make that much difference to albedo.

    That's a key difference between the Arctic and Antarctic ice loss.

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  • Comment number 176. Posted by john_cogger

    on 2 Nov 2013 14:13

    @175 mjmwhite

    Well I never knew that this science business was as easy and using 2 data points and subtracting one from t'other. Forget about the 351 data points in between...

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  • Comment number 175. Posted by mjmwhite

    on 2 Nov 2013 11:44

    http://wattsupwiththat.com/2013/10/30/how-long-before-we-reach-the-catastrophic-2c-warming/

    Fig 1 Central England Mean Monthly Temperatures 1659-2012

    As part of this presentation I point out that the temperature from 1659 to 2012 has only increased 0.87 Deg C in 353 years, or equivalent to 0.025 Deg C/decade. Considering this is a recovery period from the Little Ice Age it is hardly surprising and just part of natural variation. At this stage I normally get a few “really?” questions.

    “The UK MetOffice’s own figures”, I reply.

    The other day however was a bit different, someone in the audience asked “so how long will it take to get to the dangerous 2 Degrees C?”

    Pause, why hadn’t I worked that one out before? Quick calculation done, 800 years I replied.

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  • Comment number 174. Posted by QuaesoVeritas

    on 2 Nov 2013 10:37

    #168.Picky Paul

    "There are a number of reasons why warmer temps could result in more sea ice. "

    So, as long as temperatures continue to rise, so will the sea ice extent?

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