AustinG, probably you know that visible (and longer) irradiance varies only a small amount with SSN. UV light varies a lot more. People looking for mechanisms as I (incompletely) described above, are looking at UV and charged-particle fluxes in the upper atmosphere. Getting that (whatever it is) down to the troposphere, where weather systems move around is the problem. Joanna Haigh could explain it much better, I am sure.
Extrasolar cosmic ray fluxes reaching te earth are inversely related to SSN. So that is not a good place to put the "=" sign.
Not twisting, trying to correct the tortured logic to what I think you are trying to say. Sun spots are a proxy for solar radiation, but we have satelites now monitoring radiation, so we don't need sun spots anymore, except to test theories on the past. The quantity of solar radiation is important to all the climate models. The type of radiation though, and its effects are still being studied. Radiation goes in cycles, so single snap shots of sunspots today don't really help, you need to look over time to get a good model.
After having read the Freeman Dyson interview at #10, why not stop by Why trust climate models? It’s a matter of simple science | Ars Technica for another perspective?
I would not call CO2 a witch. Besides being indispensable for photosynthesis, it appears essential to get Earth out of ice ages. Seems that we talked about Shakun 2012 in that regard. Being sure that we would all be better off with 500 (or more) ppm instead of, say, 400 or 350 ppm CO2? It requires a concerted effort to selectively read, and misunderstand science to become sure of that. Such an effort might very well resemble witchcraft. But I would not label it so, and each person should draw their own conclusions.
I understand completely that we do not have the data, and without the data how could I agree with accepting or rejecting a theory. Here is part of the theory as far as noaa's perspective The Sun and Sunspots Now when we look at the solar cycles since satelites have been up, we have had a great deal more sun spots than during the Maunder Minimum. Until we have a period of low sun spot activity (through whole cycles not just in a cycle) how can you conclude that sunspots do not influence radiation which influences cooling. He have a hypothesis that is wating for data, we can not wish it away without the experiment. italics mine in the NOAA article. If you reject differences in radiation, how do you explain the little ice age that is not only present in written history, but throughout the world wide proxy record? What made it get colder, then warmer? If you reject this mechanism, you must be able to supply another.
Very useful excerpt from NOAA there. From SSN max to min, the visible radiation varies by about 1%. THe UV may vary 10% or more, I am not sure of the number. The missing mecanism, it seems to me, is how variable UV affects climate. We don't know what visible and UV irradiance were during the Maunder Minimum. Could have been lower than during a 'typical' SSN minimum.
Absolutely, and we have not even had a low cycle (although this one appears to be the lowest since satellites recorded radiation) to gather the data to see what actually happens with much lower sunspot numbers. The theory only needs a black box all things being equal high sunspots over multiple cycles -> warmer temperatures low sunspots over multiple cycles -> cooler temperatures Hopefully mechanisms will be found or data to reject this hypothesis, but mechanisms are not needed to gather data. One possible bit of data, encapulated in the hockey stick, was that the MWP and LIA were only regional, so that global warmer and cooler temperatures did not occur. We have since found that this data was flawed, and proxies were used that related more to ghg than temperature, along with ignoring a great number of proxies. Current reconstructions even by the hockey stick authors, now clearly show the MWP and LIA in temperature reconstructions. As for mechanism, we did not need a mechanism for sun exposure to cause sunburn, only black box models. Currently we have found the mechanism for UVB to damage dna in skin cells, this is also one of the paths to skin cancer. We have also found how UVB is one necessary part of synthesizing viteman D in humans. These discoveries are fairly recent, but the mechanism was not necessary to know that people that stayed inside all day suffered vitemin deficiencies (lack of sun) or that coverings or lotions could help prevent sunburn.
WOW you guys sound like a couple of deniers. UV from the Sun has been very high recently.Stratospheric temps raised as I recall. Could be a clue.
"The Science is Settled" means turn off your mind. Dont look behind the curtain. Dont pay any attention to the little man pulling the levers.
I like the idea @29 of using remote sensing to look at stratospheric T records. Different outgoing infrared wavelengths are meant to correspond with different atmospheric levels including stratosphere. Since 1978 I think, from Huntsville and at least one NASA direct source I think. Eleven-yeart stratos T cycle should pop right out if it is present. Plus, the signals can be resolved into latitude belts that could help with the weather-system hypothesis I mentioned above. So this is a positive contribution, hope somebody follows up on it.
I find that there is a lot of literature concerning cloud cover and climate and cosmic rays. Without aspiring to summarize it, I will mention two that are online for free Trends in Observed Cloudiness and Earth’s Radiation Budget What Do We Not Know and What Do We Need to Know? Joel R. Norris and Anthony Slingo, 2009 A cosmic ray-climate link and cloud observations Benjamin A. Laken, Enric Pallé, Jaša Čalogović and Eimear M. Dunne, 2012 If anyone finds a recent review that can be understood by non specialists, please post it here.
