Finishing up on Dana's question on the sun here:
http://answers.yahoo.com/question/index;_ylt=AlDL4qtFg1yCgUGN8xNf40Psy6IX;_ylv=3?qid=20080812141634AA1SRcI&show=7#profile-info-20f3291b9320a302e9070bf55325531daa
I didn't get a chance to respond to his response, so
"bob326 - Meehl states 'radiative forcing from increasing greenhouse gases is dominant for the response in the late twentieth century' and discusses solar amplified by anthropogenic effects."
Wrong paper. The climate commitment study I was speaking of was:
http://www.sciencemag.org/cgi/content/abstract/307/5716/1769
And yes, I know Meehl agrees with AGW theory and the study is about GHGs, but if you can think past that you can learn how even fixed forcing agents (meaning the sun in this case) can influence temperatures for centuries to come.
"Also, there is no 30 year solar lag. Thus a significant fraction of the recent warming cannot be blamed on the Sun, even by your own citations."
Of course there is no 30 year solar lag, but that isn't what I was arguing, and if you had read my post you would have understood that. I will repeat what was in my post: After the plateau in solar activity, most of the temperature response should occur in the first few decades, although arguably, that response was delayed by the causes of the midcentury cooling (aerosols, ocean circulations, etc..). All forcing agents, including CO2, have trouble explaining the mid-century cooling without bringing aerosols into the equation, and solar is no different.
Now onto the question: We are starting to find out that solar irradiance varies much less than previously thought (see J Leans earlier work vs. Svalgaard's more recent reconstruction), and yet we are very certain that these small changes in irradiance along with other solar variables can produce large changes in Earth temperatures and climate through a complex set of feedbacks. Much of this process is poorly understood.
So, given our level of understanding, can we be so sure that the sun isn't playing a larger role than the IPCC assigns it?
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