On Fri, 17 Jan 2014 10:37:54 +0000
Martin Brown wrote:

On 17/01/2014 09:10, Jim wrote:
http://www.bbc.co.uk/news/science-environment-25771510

Thoughts?

It is true we haven't seen such a low solar sunspot maximum since
about 1930 but then the recent ones have all been more active than
average!

There's another problem in that some of the data may be incorrect and
that the high values last century were exaggerated by changes in
counting methods. I understand that some re-assessment is going on but
I've no idea when or if anything will come of it.


Here is the Zurich number data as a graph:
http://solarscience.msfc.nasa.gov/im...olor_Small.jpg

They are hamming it up something rotten. It is just possible that the
trend is towards less activity with each successive cycle, the
present level of solar activity is no different ot what it was
between 1880 and 1930 or further back 1800-1820. It is nowhere near
Maunder minimum yet!

The sunspot number does vary considerably from cycle to cycle and the
peak in 1958 was abnormally high. Halving the number of spots between
successive maxima has also occurred as recently as 1957 vs 1970.

As I suggested above, that 1958 peak may have been over-egged. I think
it was also suggested that the Maunder minimum may not have been as low
as previously thought.


A quieter sun might well make for a cooler Earth, but it is far from
clear that the sunspots really are about to all vanish. We had a
naked eye sunspot and a fat X class flare CME just miss us during
Astronomy week which if it had hit would have provided an auroral
display across most of the UK.

If I had to bet I would guess that the next cycle 25 will be about
the same or more active on the basis of regression towards the mean.


The provisional sunspot number for last year was 64.9. Last year was
due to be the peak of cycle 24 and I reckon the average value at a peak
should be 93. However, as we are in a declining situation for sunspots,
the peak of this cycle could be delayed by a year or two. Mind you,
it's already been 13 years since the peak of cycle 23 as that arrived a
couple of years early.



--
Graham P Davis, Bracknell, Berks. Mail: 'newsman' not 'newsboy'.
The pen is mightier than the sword, and considerably easier to write
with. - MARTY FELDMAN