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Could a cooling sun save the planet?

Tom Feilden | 10:36 UK time, Tuesday, 21 April 2009

Quiet sunIt might not seem like it given the wonderful weather, but the Sun seems to be asleep on the job.

Images taken over the last year show virtually no sun-spot activity and very few solar flares. The observations, which will be presented at the UK National Astronomy Meeting later today, are baffling scientists.

The Sun normally undergoes an 11-year cycle of activity, spitting out flares and planet-sized globs of super-hot gas at its peak, before settling into a calmer period. According to the pattern of recent years the Sun's activity should have started to pick up again, but that simply hasn't happened.

Instead astronomers have been confronted with a 50-year low in solar winds, a 55-year low in radio emissions, and a 100-year low in sunspot activity.

A similar quiet spell in the middle of the 17th Century - known as the Maunder Minimum - lasted 70 years, and coincided with a "mini ice-age".

That's led some climate scientists to suggest that a cooling Sun could undo much of the damage wrought by global warming.

Climate sceptics have gone further arguing that the Sun - rather than man's activities - may be the main driver of climate change. The argument came to a head with the broadcast of Channel 4's The Great Global Warming Swindle in 2007, which focused on the cosmic ray theory.

But speaking on the programme this morning Mike Lockwood from the Rutherford Appleton Laboratory said the cycle of the Sun's activity didn't fit with the longer term trend towards global warming.

Solar activity began to tail off in the mid 1980's - a period of steadily rising temperatures. If the Sun was responsible for global warming we would have seen a much more marked decline by now.

Dr Lockwood believes the latest data settles the debate. The Sun has an impact on global temperatures, but it's not enough to account for climate change.

"If the Sun's dimming were to have a cooling effect, we'd have seen it by now," he says.


  • Comment number 1.

    If there was a quiet spell for the sun in the 17th century called the Maunder Minimum and it coincided with the mini ice age, wouldn't that be considered as the sun's cycle affecting the Earth's climate, or do they attribute the mini ice age to something else?
    If the argument is true that the sun's output does affect the earth's climate, and I think it's only common sense to believe that, then maybe they are looking at this the wrong way.
    Maybe the sun's lower output is helping to keep the Earth's warming due to man's mismanagement down to a more subtle climb in degrees. Maybe if this wasn't happening with the sun, our polar ice caps would have been gone already, and our oceans already 15 meters higher.
    I don't discount the global warming caused by man, but I wouldn't discount the sun's output by any means either. It isn't just one or the other. They are both playing some role in our climate.

  • Comment number 2.

    Please could you inform Dr. Lockwood that the planet has been cooling since 1998.
    Go to
    to verify this.
    What your piece confirms is that Other Factors will overwhelm the (very modest) effects of CO2.
    This is also worth viewing:

    When will we get a sensible and balanced debate about the real nature and causes of climate change? Apart from your item on Today, I have heard nothing for years on the Beeb to counteract the relentless wave of "Green" propaganda coming at us from all sides.

    It's the Sun, Stupid.

  • Comment number 3.

    Mike Lockwood from the Rutherford Appleton Laboratory also fails to take into account the seas. Any fluctuations in temperature have a dampening effect due to the temperature storing capabilities of the seas. So temperatures rise slowly or drop slowly.

    Just because the sun turned down a few notches in 1988 doesn't mean it's an instant effect.

    But I'm absolutely outraged when the most zealot of climatologists claim the sun has NO affect on the Earths temperature. Really? Because it seems to me that Mars is a lot colder than the Earth whilst Mercury is considerably hotter. I wonder why?!

  • Comment number 4.

    Sure a minimum in the solar sunspots coincided with a cool period around Europe.

    But one swallow does not a summer make.

    There have been several other periods of sunspot minima which do not coincide with a decrease of temperature on earth, and there have been several other mini-ice ages on earth which do not correspond to a sunspot minima. In fact, there is only one single cross-over point between sunspot minima and mini ice ages. And several dozens of unconnected events.

    The sun-climate link is not new - the theories being bandied about by the climate warming skeptics are not new. And, like the rest, any correlation the skeptics pull out of the hat will fall apart when faced with real data. The only theory which has stood up against every test so far is that humans have caused global warming due to increased emissions. Until a different theory stands to the same level of tests as this one, then we have to assume we are to blame.

  • Comment number 5.

    Let's point the finger of blame.
    Man caused it.
    The Sun caused it.
    Piles of Bat droppings caused it.
    The truth is that there is not one single point of blame. Like all cause and effects, there is no one single point of failure. Everything we do, has to some degree, and effect on multiple other events.
    Sun cools, intensity of temperature at the equator drops, mini ice-age occurs starting at the poles, cooler air circulates over the oceans, weather systems are affected globally, but there's nothing there to say it's bad.
    Some elements of climate change are natural. There has been climate change going on for millions of years. Man has only been sticking his finger in the pie for a few millenia or so.
    I don't think that there is any danger of the sun 'going-out' for the next few million years, and unless going quiet is a precursur to going super-nova, I think we'll all adapt.
    Earth life, man included, has adapted a few times already - and we'll continue to do so.


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