OK, lunch time and another shot at global warming.
Let me first dispel FL2s favorite plot, originally posted by gene90 in an earlier thread and totally discredited by me at that time. He posted in here:
http://forums.civfanatics.com/showpost.php?p=3006690&postcount=44
The famous lassen curve from the article "Length of the solar cycle: An indicator of solar activity closely associated with climate"
Heres my original response.
http://forums.civfanatics.com/showpost.php?p=2527451&postcount=200
The upshot is that through some data manipulation lassen did show a correlation, but even with that manipulation the current trends are out of wack (with the 11 year solar cycle, the data used in that publication).
Heres a plot of the real solar forcing along with glaciation over the last million years, just for fun,
This is known as the Milankovitch cycle.
Oh and this quote by FL2
The graph shows the relationship between insolation (incoming solar radiation) and earth's average temperature. The correlation is undeniable, and even in later years deviation is minimal. The conclusion any sentient person would come to is that CO2 emissions from technology are not the main cause, or even a significant factor in, global warming.
indicates just how little he understands, or even looks at what he posts.
Good job to Pikachu here:
http://forums.civfanatics.com/showpost.php?p=3007411&postcount=72
Now Basketcase:
Clouds have a warming effect (water vapor is a greenhouse gas) and a cooling effect (reflection of radiation back into space).
You have learned well young padawan.
Water stores heat a lot more efficiently than the land does (meaning that water warms up by a smaller amount when it absorbs the same amount of heat), so you have to consider where all the heat is going.
That is what climate models do.
One of the web sites I browsed while examining the subject had a pair of graphs showing temperature in the troposphere and stratosphere over a couple hundred years--these two adjacent layers in the atmosphere had NO relation to each other on the graphs! Warm trends in the troposphere did NOT have matching trends in the stratosphere. Cleary there was a problem there--what kind, I don't know. Could have been that people were simply measuring wrong.
This is not hard to explain. Greenhouse gasses in the troposphere warm it through increased absorbtion of infrared radiation (the primary heat source down here). Greenhouse gasses in the stratosphere actually cool it because the main heat source is due to ozone, the greenhouse gasses act like a radiator cooling it. This is also the cause of the difference between surface measurements and MLS type satellite measurements of temperature.
Finally Urederra and the Medieval warm period, etc.
It is pretty well agreed now that this was a local phenomena and not a globally warm period. This was played out in Science and Nature around 2001-2002. But the little ice age does seem to have been global, and shows up in temperature reconstructions such as the Mann one (there are others). Some recent ones are:
Climate change of the last 2000 years inferred from borehole temperatures: data from Hungary
Global and Planetary Change Volume: 41, Issue: 2, April, 2004, pp. 121-133
Bodri, L. ; Dövényi, P.
Ground warming patterns in the Northern Hemisphere during the last five centuries
Earth and Planetary Science Letters Volume: 227, Issue: 3-4, November 15, 2004, pp. 169-177
Beltrami, Hugo ; Bourlon, Evelise
Temperature variability over the past millennium inferred from Northwestern Alaska tree rings
Climate Dynamics Volume: 24, Issue: 2-3, February 2005, pp. 227 - 236
DArrigo, Rosanne ; Mashig, Erika ; Frank, David ; Wilson, Rob ; Jacoby, Gordon
Ground Surface Warming History in Northern Canada Inferred from Inversions of Temperature Logs and Comparison with Other Proxy Climate Reconstructions
Pure and Applied Geophysics Volume: 162, Issue: 1, January 2005, pp. 109 - 128
Majorowicz, Jacek A. ; Skinner, Walter R. ; Safanda, Jan
The unique thing about Manns work was that he compiled all available records and did a global analysis.
McIntyre and McKitrick excluded much of the instrumental temperature record in their reconstruction. Specifically that from North America. They also misused PCA (principle component analysis).
Heres a reference of the first response: Jones, P.D., Mann, M.E., Climate Over Past Millennia, Reviews of Geophysics., 42, RG2002, doi: 10.1029/2003RG000143, 2004.
A simplified version is here:
http://www.realclimate.org/index.php?p=121#more-121
There will be additional publications on this topic shortly. Im sure you know that the controversy between surface and satellite measurements has been cleared up recently.
Dont just dismiss it because it includes analysis by Mann (who understands the issues better). If you have a problem with the analysis please bring it to light here.
Finally, let me wrap up by saying that it is a fact that anthropogenic activities have significantly and demonstrably increased the infrared opacity of the troposphere. It is undeniable that this affects planetary energy balance in the short term, and the whole earth system in the longer term.
I prefer the term 'climate change' to global warming, and it is pretty clear that anthropogenic aerosols are as important as greenhouse gasses to climate change.
This to me is the real issue, not paleoclimate reconstructions where boundary conditions are unknown and resolution is poor, but current climate studies where many more variables are constrained. The topic being not if anthropogenic climate change is a fact, but what its effect will be.
Have a good "holiday" 
Isnt this what you would call an attack ad hominem?
