So if this is the cause of a possible slowing in the rate of climate change - what happens when they come back?

It's more of a case of when surely?

I was following this for some time, past 6 months, from an investment newsletter. The author does not believe in global warming and thinks the sunspots or lack of them will teach the believers a lesson. I think he has a personal problem with Al Gore.

We will know in a few years, in the meantime if the climate does cool for the next few summers we could have new food shortages in some parts of the world. The thesis from an investment POV was that agriculture stocks were a good buy because of this, FWIW.

Anyway, another climate puzzle, if sunspots do influence the climate (they had been discounted by most in the scientific community) then it will another revision of the climate models....

So Whitehouse, in the Independant, concludes "For now, all scientists can do, along with the rest of us, is to watch and wait."

Rubbish.

If you want to learn about climate science ask a climate scientist not a jounalist (or at least not that journalist).

This article from RealClimate last week is more useful:
http://www.realclimate.org/index.php/archives/2009/04/yet-more-aerosols-comment-on-shindell-and-faluvegi/langswitch_lang/sw

Posted By: trule Anyway, another climate puzzle, if sunspots do influence the climate (they had been discounted by most in the scientific community) then it will another revision of the climate models....

The suns variability is already taken into account in climate models. Indeed there is evidence the models assume the sun has more effect than it actually does...


http://en.wikipedia.org/wiki/Solar_variation

In their Third Assessment Report, the IPCC state that the measured magnitude of recent solar variation is much smaller than the amount of predicted climate change due to greenhouse gases. [44] In 2002, Lean et al.[45] stated that while "There is ... growing empirical evidence for the Sun's role in climate change on multiple time scales including the 11-year cycle", "changes in terrestrial proxies of solar activity (such as the 14C and 10Be cosmogenic isotopes and the aa geomagnetic index) can occur in the absence of long-term (i.e., secular) solar irradiance changes ... because the stochastic response increases with the cycle amplitude, not because there is an actual secular irradiance change." They conclude that because of this, "long-term climate change may appear to track the amplitude of the solar activity cycles," but that "Solar radiative forcing of climate is reduced by a factor of 5 when the background component is omitted from historical reconstructions of total solar irradiance ...This suggests that general circulation model (GCM) simulations of twentieth century warming may overestimate the role of solar irradiance variability." More recently, a study and review of existing literature published in Nature in September 2006 suggests that the evidence is solidly on the side of solar brightness having relatively little effect on global climate, with little likelihood of significant shifts in solar output over long periods of time.[11][46] Lockwood and Fröhlich, 2007, find that there "is considerable evidence for solar influence on the Earth’s pre-industrial climate and the Sun may well have been a factor in post-industrial climate change in the first half of the last century," but that "over the past 20 years, all the trends in the Sun that could have had an influence on the Earth’s climate have been in the opposite direction to that required to explain the observed rise in global mean temperatures."[47]

This part of your quote:

"is considerable evidence for solar influence on the Earth’s pre-industrial climate and the Sun may well have been a factor in post-industrial climate change in the first half of the last century,"

is the bit that could cause problems for the models and climate change theory if the Sun's behaviour does in-fact change again. Keep in mind that the IPCC is consensus and it is not absolute, note the use of "suggests" and "may", this means they think its the case but might change their minds if new evidence is presented. People looking outside the consensus are probably where the next ideas will come from and where the new improved models will be born.

Actually they even give probabilities for several words:- "most" means greater than 50%, "likely" means at least a 66% likelihood, and "very likely" means at least a 90% likelihood of


Basically, you can't take IPCC reports as absolute fact, they are a consensus best guess based on the science of the day. The weakness of this is best shown where the wiki suggests that "U.S. negotiators managed to eliminate language calling for cuts in greenhouse gas emissions", the exact sentence removed was, "Mitigation measures will therefore also be required.". You can see the problem right there.

So the IPCC reports make nice reading but keep some grains of salt close by and apply as needed.


As for the sun spots, they are an interesting side story if only because they are late and we don't know why AFAIK.