"Finally an opinion of my own: Press release or not, I am in no way out to attribute what has gone on in the last century solely to cosmic rays or anything else and I am certainly not out to belittle the effect of CO2 and other greenhouse gases. To me this is simply an interesting piece of science that looks like it could be another piece of the climate puzzle. If the size of this piece is big enough to make an impact on past, present or future climate is the subject of future research."
Interesting that no one else is attributing what has gone on "solely to cosmic rays or anything else" either. Certainly all factors must be given their due, including the many factors covered in my comments which the UN/IPCC has most certainly chosen to minimize seeing as, in the words of one researcher, "All calculations about the greenhouse effect and global warming assume cloud cover isn't changing,".
In this person's opinion it would appear as though the UN/IPCC would certainly like to be able to attribute all global climate change to varitation in atmospheric CO2. However I most certainly give CO2 variation its due, (i.e.direct radiative effect of 0.2oC per each doubling of atmospheric concentration) as you well know.
"the direct radiative effects of doubled CO2 can cause a maximum surface warming [at the equator] of about 0.2 K, and hence roughly 90% of the 2.0-2.5 K surface warming obtained by the GCM is caused by atmospheric feedback processes described above."
--- "Increased Atmospheric CO2: Zonal and Seasonal Estimates of the Effect on the Radiation Energy Balance and Surface Temperature" (V. Ramanathan and M. S. Lian), J. Geophys. Res., Vol. 84, p. 4949, 1979.
I just happen to hold that other factors such as Solar activity mentioned above in #3, #6, & #7 impact earth's climate swamping out that of any very small contribution of anthropogenic CO2 accumlations in the atmosphere over natural variations due to external factors affecting cloud cover as well as direct irradiation.
While I will grant the investigation of cosmic ray influence on clouds and Earth's climate has merit, as noted in the recent post on RealClimate (including the response from one of the involved researchers, #7), considerably more work needs to be done.
Oh indeed considerable more work needs to be done, especially by the UN/IPCC global climate modelers, seeing as "All calculations about the greenhouse effect and global warming assume cloud cover isn't changing," in the words of one researcher. We must note that, obviously, not all factors are being taken into proper account where the reckoning of the the IPCC and global warming crowd is concerned.
Especially when we consider, that observed variations in cloud cover in just a five year time frame account for as much as 1.2 watts variation in Earth's surface heating. In the words of Svensmark, “That figure can be compared with about 1.4 watts per square meter estimated by the [United Nations’] Intergovernmental Panel on Climate Change for the greenhouse effect of all the increase in carbon dioxide in the air since the Industrial Revolution,”
Based on somewhat exhaustive Web research, the accepted direct radiative forcing from doubled CO2 is ~0.9 C. (globally). You and a couple of others attempt to distinguish between surface warming and total global warming; I can't pursue that with sufficient detail to determine if that discrimination is a valid approach.
I just happen to hold that other factors such as Solar activity mentioned above in #3, #6, & #7 impact earth's climate swamping out that of any very small contribution of anthropogenic CO2 accumlations in the atmosphere over natural variations due to external factors affecting cloud cover as well as direct irradiation.
And while we disagree on the relative sizes of each forcing, we agree that cloud effects are the dominant uncertainty (as I also agree with FR "palmer"). This agreement underscores your final comments here. The problem I perceive is that cloud cover could be a significant positive feedback, a minor positive feedback, no feedback either way, a minor negative feedback, or a significant negative feedback (and it sure would be NICE if it was the last). So a range of possibilities must be evaluated and a risk-analysis based on those possibilities must be formulated. Those who are risk-averse to the possibility of irreversible major climate effects (I put myself in that category) would favor more rapid and dramatic action than those who are less risk-averse.