[Coral-List] AGW, solar activity, etc

[Jeremy Kemp]

I’ve been
following the AGW comments on the list: definitely good to have the Anti GW /
Anthropogenic GW confusion apparently cleared up.

 

Gene, you make
one or two statements about AGW and ‘uncertainties’ in your response to Milton
which I have to pick up on. Specifically, you mention uncertainties about
causal mechanisms including the sun and / or “the Earth’s position in the Universe”.
I’m not sure what the latter refers to (maybe the galactic rays hypothesis?),
but the influence of the sun is actually well characterized, and the use of
variations in solar output as an argument to explain recent warming is thoroughly
debunked. In fact, now and during recent years, the sun has been in a
relatively cool phase. The skeptics have done a great job of sowing the seeds
of confusion globally on that issue, and even though counter-factual it’s still regularly trotted out as
‘proof’ that AGW isn’t happening.

 

If galactic rays
is what you’re referring to on the other issue, that is also extremely
questionable, pretty much to the point of being discredited. The original work
(primarily by Friis-Christensen &
Lassen, and Svensmark) has been well critiqued by, for example, Benestad, and Damon & Laut. Their work has not, to my knowledge, been convincingly
critiqued in return. Similarly to solar output, galactic rays are an ‘issue’
regularly used by so-called skeptics to muddy the waters.

 

Anyone wanting
to keep up to date with developments in the AGW field might find
RealClimate.org useful. It’s probably the public ‘forum’ (for want of a better word)
that is most widely used by reputable climate scientists. The scientific (i.e. based
on genuinely peer-reviewed literature) basis for and against most arguments can
be found on there.

 

Jerry Kemp(Edinburgh University)