Global Warming is Man-Made

AGW Models fail, so the theory is wrongWe have agreed on a couple of basic points of climate science: 1. If AGW is true then warming should occur as a straight line over time. 2. The heat output of the sun is not changing, so that isn't upsetting the straight line AGW So, if AGW has dominated climate over last century then we should see a straight line increase in temperature over the century, with just short term variations due to weather. Here is the temperature data. Pro told us in his initial argument that the minimum value for climate sensitivity under AGW is 3 degrees per century. He said it might be more, but it's at least three degrees. To test if AGW dominates climate, we can see how close the temperature data is to a straight line with a three dree slope. I took the temperature from Wikipedia [1] and added the line (in blue) predicted by AGW: Clearly AGW theory is wrong. It's possible that carbon dioxide is adding a temperature increase to climate just as AGW predicts, but that some other unaccounted factor is canceling the AGW before about 1980 and after about 2000. Our debate is about whether AGW dominates climate, so if it is try that an unknown factor completely changes climate from what AGW contributes, then it is the unknown factor that dominates, not AGW. Why did a theory so far from the data ever take hold? The problem AGW attempts to explain is the rise from about 1980 to 1996, and many atmospheric scientists could not come up with an explanation other than CO2. To explain all the pre-1980 data that did not conform, Professor Mann and his colleagues came up with the Hockey Stick curve, that purported to show that climate had not changed at all in the past 1000 years. The Hockey Stick turned out to be the product of a bad statistical method that selected proxies for temperature that were unrelated to temperature. The current Wikipedia article on the Hockey Stick shows the Medieval Warm Period and the Little Ice Age as global climate change. Both are explained by solar magnetic theory. The fatal blow to AGW theory is the lack of warming since 1996. The blue curve on the graph shows how far we are below the AGW theoretical prediction. Pro argues that the HADCru data shows some warming, but there is close to universal agreement that the models have failed. HADCru uses ground station data which focuses on urban areas that warm due to growth with surrounding population increase. The satellite data covers the whole earth with no such complications. NASA acknowledges the pause in global warming [2] the ‘pause’ in global surface temperature that began in 1997, according to some estimates, continues,” wrote David Whitehouse, who holds a doctorate in astrophysics and was the BBC’s science editor. “Statistically speaking there has been no trend in global temperatures over this period.” HADCru fully acknowledges the existence of the pause in global warming, but dutifully insists that the underlying AGW has just been overcome by other factors. Those factors must, of course, now dominate AGW. [3] Papers by von Storch [4] and Rasmussen [5], both previously vigorous defenders of AGW, show the AGW models have failed. Not only have the models failed, but there is no way to tweak them, say by changing climate sensitivity, to get them to fit the data. A book by Tisdale [6] shows graphically that the models cannot be fixed. Measures of Solar ActivityRemember, I'm not obliged to explain why the AGW models have failed, only that there is no possibility that the AGW linear trend of 3 degrees per century, which Pro claimed as all but certain science, is not true so that AGW is not dominating climate. The exact nature of the sun's influence on climate is not known, and Pro argues convoincingly that the length of the solar cycle has not been born out as being as good a predictor as thought. Nonetheless the correlation to solar activity remains strong. The long Medieval Cold Period, the Medieval Warm Period, and the Little Ice Age all corrsponded to solar activity. [6] Right now we are in a period of decreasing sunspot activity [7]: That the correlation to sunspot activity is not perfect means no more than that climate is complex. To say that AGW dominates climate is unfounded, because there is all but universal agreement that the models have failed.Paleoclimate That CO2 lags warming is uncontested basic physics. As the oceans heat, CO2 comes out of solution and CO2 enters the atmosphere. If it amplifies heating trends, that is no proof that CO2 dominates climate. Whatever starts and ends the heating trend dominates climate and CO2 magnifies the swings in boith directions.Whether the present is warmer than the Medieval Warm Period or the Roman Warm Period is not the slightest proof of what caused any of the warming or cooling. What is does show is that substantial warming in past climate has happened without any CO2 effect. If we got nearly as warm as the present in the MWP. then whatever caused that was not CO2 and may be working now.The long history of climate shows very little relationship to CO2, and Pro acknoweldges that. So what factors were at work, and how do we know what is at work now? Variations in the earth's orbit are not nearly enough to explain the changes. We have some ideas, but there is nothing that's proved reliable, especially not AGW theory.Pro burden is no more than to prove that AGW dominates climate. He has not done so.