On 02/06/2013 02:48 AM, Chuck Sites wrote: > Sunspots do reduce the solar input and during peak sunspot activity it > can be as high as 15% more or less. Think about it. Sunspots are > dark; Dark spots emit less light. So more sunspots, less light. Less > light, less Solar input. Less solar input should mean less average > global temperature rise from sun cycles.. What does effect the solar > input is seasonal. The Earth-Sun orbit is elliptical so at certain > times of the year we are closer to the sun than the other half. So > yes Craig, I will agree that on the solar input side of the global > warming equation you have many variables that can influence the input, > but let me point out that has been happening for millions of years > with little variation from what is happening now.
It's well documented that sunspot number correlates directly with total solar irradiance. The easiest source is Wikipedia: "The net effect during periods of enhanced solar magnetic activity is increased radiant output of the sun because faculae <http://en.wikipedia.org/wiki/Faculae> are larger and persist longer than sunspots <http://en.wikipedia.org/wiki/Sunspots>. Conversely, periods of lower solar magnetic activity and fewer sunspots (such as the Maunder Minimum) may correlate with times of lower terrestrial irradiance from the sun.^[25] <http://en.wikipedia.org/wiki/Solar_variation#cite_note-25>" This group reconstructed historical solar irradiance levels from using sunspot data: http://lasp.colorado.edu/lisird/tsi/historical_tsi.html If this is a sticking point, we can certainly find more information on this. > > Craig; the only conclusion you can deductively come to is that the > average global temperature increase over the past 68 years is caused > by human activity and based on the scale, it's human industrial scale > activity creating CO2 as a byproduct. But this is a big leap. Sorry. It may be correct, but it's not obvious to me. What I want to do is dig deeper into how the models are being constructed which recreate the historical temperature record. I don't know when I can get to this, but that's the next step. I'll also look into finding the objections by those on the AGW side against the correlations with total solar irradiance. > Craig, what convinced be about global warming wasn't all the numbers > facts and figures, It was looking up in the sky and seeing all of > these very high altitude clouds. Water vapor lofted up to the > stratosphere by additional thermal energy dumped in the oceans from > global warming. I encourage everyone to look for the really high > vapor clouds. > Are you suggesting that we have more cirrus clouds than we used to have? The convincing arguments should not be something you see in the sky, but rather something you can demonstrate that goes back centuries. For instance, if CO2 directly correlated with increases in temperature on an annual basis, and could explain, by itself, all the peaks and valleys of the temperature record for the past couple of centuries, and if there was not an alternative hypothesis, then it would be hard to deny the correlation with the CO2 record and global temperature anomalies. However, with an alternative hypothesis present, which may better explain the temperature record with all of its fluctuations, doubt will always remain with any explanation based on correlations for the simple reason that it's not possible to prove cause with correlations. One side will 'win' this argument, (if it's possible to 'win' in science), when one correlation or the other diverges significantly from its expected result. Solar output has been decreasing these past 10 years. Now global warming has stalled. It continues to look like solar output will continue to decrease for the next couple of decades. If this happens and global temperatures fall, then more credence will be given to the impact of solar irradiance. If global warming continues, however, diverging from the models based on the alternative hypothesis, then the issue will be effectively resolved, as well, in favor of the CO2 correlation. Craig
