Climate change

We have an unresolved disagreement about what contribution of CO2 to climate is "significant." CO2 theory advocates generally attribute all of climate change to CO2. They argue that there is no significant solar activity of any kind, that arctic ice could not have melted due to the Pacific Oscillation by which it has melted regularly in past times, and that hurricanes that used to run in cycles no longer do so. So for debate purposes, I'd say that if half of global warming were due to CO2, that would be significant. Pro suggested in round 2 that "significant" ought to be judged as enough to make enacting cap and trade worthwhile. By that standard, then if all of global warming is due to to CO2, it still wouldn't be significant. That's because Europe enacted cap and trade some time ago, and CO2 was not reduced at all as a consequence. The Holocene Optimum (3000-5000 years ago) was warmer than CO2 theorists claim it will get, and that was one of the most prosperous periods of human history. The polar bears survived as well. If Pro understood that no scientist opposed to CO2 theory maintained that global warming did not exist, then why did he put it as the first contention of his debate argument? Whether Pro believed the error of fact or not, it appears in Pro's argument, and is therefore relevant to the debate. Having the contention implies that those who deny the theory is completely out of touch with reality. Therefore is was relevant to refute the implication. I did the analysis of CO2 effects on Venus correctly. I acknowledged that 380 ppm (I should have said 368 ppm, which is more accurate.) of CO2 leads to our present temperature. I claimed that the sensitivity to CO2 above 380 would be small. Pro claimed that the sensitivity above present levels was high, and that Venus showed that sensitivity. To disprove Pro's assertion, I started with the assumption of what temperatures would be if both Earth and Venus had 380 ppm of CO2, compensating for Venus being closer to the Sun. The rise above that baseline that is actually observed is about 150 degrees and it is due to adding (960,000 - 380) ppm of CO2. That's 0.05 degree per extra 380 ppm. That refutes Pro's contention that because Venus is hot, it shows that temperature is sensitive to CO2. Note that the main greenhouse gas on earth is not CO2, it is water vapor. That allows CO2 proponents to tweak the computer models so that when CO2 fails to explain warming, an induced multiplier effect from water vapor is claimed. Pro responds by producing an unlabeled graph from an unknown source that shows that while overall there is low sensitivity to CO2, that early may be in a portion of the curve where there is still some sensitivity. The x-axis of the graph appear to be logarithmic, but it isn't stated, so we don't know for sure where the 380 point should be plotted. There is no clue as to whether the y-axis (temperature) is linear or logarithmic, so even if we knew the 380 point, we couldn't read of the temperature increase claimed for going to 760 ppm. What Pro's graph concedes is that CO2 effects are extremely non-linear. What Pro seems to disputes is the exact shape of the curve or where we are on the curve. The non-linearity of the CO2 response is calculated from physical principles by T.J. Nelson http://brneurosci.org... "What saturation tells us is that exponentially higher levels of CO2 would be needed to produce a linear increase in absorption, and hence temperature. This is basic physics.... doubling carbon dioxide would not double the amount of global warming. In fact, the effect of carbon dioxide is roughly logarithmic. Each time carbon dioxide (or some other greenhouse gas) is doubled, the increase in temperature is the same as the previous increase." Nelson continues by fitting the CO2 data from the 20th century to the known temperature rise. "This shows that doubling CO2 over its current values should increase the earth's temperature by about 1.85 degrees C. Doubling it again would raise the temperature another 1.85 degrees C. Since these numbers are based on actual measurements, not models, they include the effects of amplification, if we make the reasonable assumption that the same amplification mechanisms that occurred previously will also occur in a world that is two degrees warmer." Pro gives references, but they are a mess of blog-like conclusions from non-scientists and biased Wikipedia articles. Moreover, Pro frequently fails to claim what it is in the article that he claims to be supporting his claim. Other times I cannot find and match at all. His [12] is supposed to support a claim about Mercury, but I cannot find any reference to Mercury. He cited an article claiming to temperature for the last decade that showed no such data. Pro should reference articles written by credible scientists and quote or say what it is that supports his point. The second graph in http://wattsupwiththat.com... compares actual temperature with climate model prediction. Temperature have been level for the past decade, and "August 2008 was 3 C below June 1988, rather than projected 5 C above" Pro claims that there is a consensus of the "vast majority of scientists" that CO2 theory is correct. The main evidence he cites supporting that claim is the IPCC report. However, the IPCC itself is 70% non-scientists, a small elite determines the conclusions and edits the chapters to match their conclusions, and none of the contributors are allowed to vote on whether the report is valid. There is no evidence that if there is a consensus at all, that it is anything like a "vast majority." In addition to the hurricane expert who quite in protest, "Dr. Vincent Gray, a member of the IPCC's expert reviewers' panel asserts, 'There is no relationship between warming and [the] level of gases in the atmosphere.' " and "the [2001] report's lead author, atmospheric scientist Dr. John Christy, to rebuke media sensationalism and affirm, "The world is in much better shape than this doomsday scenario paints … the worst-case scenario [is] not going to happen." http://townhall.com... Recently, Christy identified the clear ideological beliefs of several authors and noted, "The tendency to succumb to group-think and the herd-instinct (now formally called the "informational cascade") is perhaps as tempting among scientists as any group ..." http://news.bbc.co.uk... Pro also cites the bogus study by Naomi Oreskes, a historian who searched scientific articles and claimed to find no articles contrary to CO2 theory. Oreskes only looked to for certain key phrases in certain journals, phrases basically related to political stance on the issue. Most scientific articles don't make any conclusions one way on the other about global warming, they just report on a study of some aspect of the science. It's easy to make a list of hundreds of scientific articles providing evidence contrary to CO2 theory, but none are included in Orestes study. Separately, I have compiled a lengthy critique of the Oreskes study, http://factspluslogic.com... Pro provided a reference that shows no relationship between CO2 and global warming over the past 600 million years. There was an ice age when CO2 levels were 12 time present. Pro responds that over history there were many things going on in climate. That's true, but it also shows that whatever the CO2 effect upon climate it has been insignificant relative to all those other causes. So for 600 million years, CO2 at levels a dozen times greater than now has been insignificant, but now we are supposed to believe it is dominant. Physical theory, past history, and current observation should CO2 has no significant climate effect.