Lack of Environment

A blog on the politics and psychology underlying the denial of all our environmental problems

The Secret life of the Sun

with 12 comments

Last night in the UK, the BBC broadcast this fascinating documentary regarding the Sun (YouTube video appended below).

Dr Helen Czerski and Kate Humble

It was presented by two of my favourite TV personalities, Dr Helen Czerski and Kate Humble.

It starts by pointing out that the Sun is currently at solar maximum – the point of maximum activity in a cycle that typically occurs every 11 years.  It ends by presenting data (obtained from 17 years of continuous observation) indicating that the Sun is also now approaching a grand solar minimum – something it last did over 300 years ago.  In between, it describes all sorts of things about how the Sun works; and includes dramatic footage of Kate Humble witnessing a total solar eclipse in Australia and the Aurora Borealis in Sweden.

I thought I understood most of this stuff and so, apart from the awesome cinematography of the above events, it was tempting to think I might have heard it all before – solar wind… blah blah blah… solar storms… blah blah blah… coronal mass ejections, electromagnetic pulses, widespread power blackouts…

However, no-one should under-estimate the real problems that a coronal mass ejection (CME) could cause.  We can do this by extrapolating from (1) the effects of routine solar wind and (2) from the occasions when the Earth has been affected my CMEs in the past, such as in Quebec in 1989 and Malmo in 2003.  In both cases, however, the Earth was only affected by a small part of the CME.  If it was to be struck by the full force of a CME, the problems could be much more serious and much more widespread.  Indeed, Lloyds of London has compiled a detailed assessment of all the things that could be affected, such as: communications, food, finance, fuel, health services, sanitation, transport and water supply. [See page 15 in Space Weather: Its impacts on Earth and the implications for business (PDF)].

Nevertheless, I want to focus on the last 10 minutes of the programme, where the results of observations from the (National Optical Astronomy Observatory’s) McMath-Pierce Solar Telescope in Arizona are presented.  This has been used to look at the average strength of the magnetic field within individual sunspots for the last 17 years.  As such, it has observed more than an entire solar cycle; with the number of visible sunspots ranging from less than 5 (at solar minimum) to as many as 100 (at solar maximum).

The remarkable thing is that, instead of rising and falling during the solar cycle, the average magnetic strength of the sunspots has been steadily decreasing over the last 17 years.  This would appear to confirm the argument made by Fred Singer and Dennis Avery, in their book Unstoppable Global Warming, that the Sun also has longer-term cycles in sunspot activity.  In other words, this declining trend in magnetic field strength suggests that the Sun is now heading towards another ‘grand solar minimum’; similar to that primarily responsible for a period of colder than normal weather in the 17th Century (i.e. known as the Little Ice Age), during which the River Thames regularly froze (something it has only done once in the last 200 years – in 1963).

However, before all those climate change sceptics out there in the deniosphere get all excited, this is not good news!  Just as with the cooling effects of particulates and aerosols in our atmosphere, the effects of another approaching grand solar minimum will only be temporary.  The very best thing we can say is that, were it to materialise, another Little Ice Age would give us a little more time to phase out fossil fuels and make carbon capture and storage work.  However, the one thing it will not alter is this:  The burning of fossil fuels is the primary cause of 20th Century warming, which is an underlying trend that is likely to overwhelm all other (cooling) effects unless we stop the super-exponential growth of CO2 emissions of the last 200 years (i.e. following a ‘J-curve’ – with an annual percentage growth progressively increasing over time).

http://www.youtube.com/watch?v=l6T5TQa8MlE

Addendum (25th June 2013):  Since writing this yesterday, as stated in response to RobertScribbler below, it has occurred to me that the difference between day and night temperatures is not as great as it would be if we had no atmosphere, which suggests that what the atmosphere does is more important than what the Sun does: Let us assume that total solar irradiance could reduce by 1.5% over a 200 year period. In the 200 yr period up to that (approaching) grand solar minimum, it is likely that the average water content of our atmosphere will have increased by at least three times as much (i.e. 4.5%) and CO2 by ten times that (i.e. at least 45%). Am I right, or am I right?

About these ads

Written by Martin Lack

24 June 2013 at 14:58

12 Responses

Subscribe to comments with RSS.

  1. Yes, it was a most interesting program for me also.

    But, surely, the next solar minimum won’t be until 5 1/2 years time?

    Paul Handover

    24 June 2013 at 15:35

    • Forgive me if I have not made this sufficiently clear: The Sun would appear to have short-term cycles of sunspot activity; with an average of 11 years between “solar maxima”. In addition to this, the continuous decline in magnetic field strength over the last 17 years suggests that we are somewhere beyond the high point (i.e. a “grand solar maximum”) – in a much longer-term cycle – on the way to another “grand solar minimum” (which last occurred 400 years ago).

      Martin Lack

      24 June 2013 at 16:04

  2. The loss of radiative forcing caused by a grand solar minimum would, unfortunately, only fractionally reduce the forcing caused by human Greenhouse gas emissions, which is now at least three times that of the negative forcing caused by the last grand minimum.

    robertscribbler

    25 June 2013 at 01:41

    • Thanks Robert. Since writing this yesterday, it had occurred to me that this was the key piece of contextualising information missing from the programme. I kind of hinted at it with my remarks about industrial pollution and aerosols, which may well be the primary cause of the hiatus of the last decade. It also occurred to me that the difference between day and night temperatures is not as great as it would be if we had no atmosphere, which suggests that what the atmosphere does is more important than what the Sun does: Let us assume that total solar irradiance could reduce by 1.5% over a 200 year period. In the 200 yr period up to that (approaching) grand solar minimum, it is likely that the average water content of our atmosphere will have increased by at least three times as much (i.e. 4.5%) and CO2 by ten times that (i.e. at least 45%). Am I right, or am I right?

      Martin Lack

      25 June 2013 at 13:03

      • That sounds about right, although average loss of solar irradiance wouldn’t be quite so much. As for the ‘hiatus’ of the last decade, the atmospheric warming slowed down while warming in the oceans sped up. Since oceans contain more than 90% of the heat change, the overall warming hasn’t slowed at all. Further, ice sheet response over the past decade has been both powerful and massive. The long term forcing we’ve put in place, according to paleoclimate and our best estimates of Earth System Sensitivity, are enough to raise temperatures another 2-3 degrees Celsius (at a constant level of CO2 of 400 ppm). Even a grand minimum never moved the world’s temperatures more than 1 degree C. And that’s just putting into context what we’ve already released and what will be locked in for about 1,000 years after another ten years or so of emissions at the current rate. If we get the projected rate of emissions under business as usual (which is enough to push the world to around 900 ppm CO2 and converts to around 9-11 degrees C long-term), then it’s likely we won’t even notice a grand minimum, should it emerge.

        robertscribbler

        25 June 2013 at 16:06

        • Thanks for explaining all that so clearly, Robert. I hope Schlomo Wahl and others will take the time to read it. As I said, I wrote my post rather hastily without stopping to check the relative strength of solar cooling vs anthropogenic warming. I will try and do better next time. I hope you took a look at my critique of Singer and Avery’s silly book?

          Martin Lack

          26 June 2013 at 10:23

        • It was a good post. Just wanted to add a few thoughts. Is the critique in a different post? I’d love to read it. Will search your blog for it when I have a few moments later today.

          robertscribbler

          26 June 2013 at 22:27

        • There is no need to search anywhere, Robert. You just need to follow the link embedded in the original post (above), which takes you directly to my critique of the book – ‘Unstoppable Global Warming’ – rather than to the book itself (sales of which I would not want to facilitate).

          Martin Lack

          27 June 2013 at 09:41

  3. The slow down of the sun has bought up some time, in the last decade, true. That’s the argument in:

    http://patriceayme.wordpress.com/2009/05/31/sun-cooling-ice-melting/

    However, all and any suggestion that we are en route towards another Little Ice Age minimum is sheer speculation. More probably, we will snap back to normal any time.

    In any case, as Robbert Scribbler says, it’s a matter of one degree of cooling on one side, versus 6 degrees of warming on the other. Plus of course the fact that the CO2 EXPONENTIAL forces all dimensions of the biospheres at once, including the chemical ones (change of Ph).

    http://patriceayme.wordpress.com/2008/03/08/the-equipartition-of-energy-theorem-should-be-applied-for-climate-change-and-predicts-wild-fluctuations-of-temperatures/

    Seems like Obama has finally woken up on CO2.
    PA

    Patrice Ayme

    26 June 2013 at 19:32

  4. […] 2013/06/24: LoE: The Secret life of the Sun [vid] […]

  5. […] 2013/06/24: LoE: The Secret life of the Sun [vid] […]


Please join the discussion

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Follow

Get every new post delivered to your Inbox.

Join 317 other followers

%d bloggers like this: