Global Warming is Largely Man-Made

There are some minor issues in conduct with my opponent's constructive case, but I'm not going to dwell on them. Primarily, this argument remains unaltered from when my opponent last debated this issue, which means he has left in irrelevant rebuttals, albeit to the wrong opponent.R1: No Major/any CO2 Increase.In the previous round, I preemptively refuted this first claim that historically higher carbon dioxide are relevant. In fact, as you will see, they are, if anything, evidence in favour of carbon dioxide's effect on temperature, which Con later attempts to refute."Many skeptics claim that historically, carbon dioxide levels have been much lower, particularly around 500-600 million years ago[1]. But the carbon dioxide level is not the only factor that affect global temperature[2]. Additionally, this position fails to account for the differences in solar activity, that was drastically different from current levels. This position also fails to explain why a comprehensive analysis of carbon dioxide levels over the last 540 millions years concluded that "Periods of low CO2 coincide with periods of geographically widespread ice." This is clearly visible in this graph, where the shaded periods are periods of widespread ice."[3] I shall also strengthen this argument and adapt it to Con's specific contention.Firstly Con cites data, which no longer exists. This is bad practice. He should seek alternative data that supports his contention that, even if one assumes the data is reliable, I have unequivocally refuted.[1] http://www.lavoisier.com.au...[2] http://www.ipcc.ch...[3] http://droyer.web.wesleyan.edu...(GCA).pdfR2: [sic] Earth is cooling.This is patently not true and in most instances of my opponents argument, a bare assertion. In the others, he has cherry picked unsupported evidence. Of course the Earth has been hotter historically (due to solar activity), but this is irrelevant. In this debate we are referring to Global Warming, which is the consistent rise in temperature since the 20th century up till this point, which is clearly occurring. This figure shows the change in the earth's total heat content since 1960[1]. This more advanced graph is the average of 5 different data sets, adjusted for the short-term effects of the El Nino Southern Oscillation, solar variability, and volcanic aerosols[2]. Con then proceeds to [sic]site Don Easterbrook, who claims his model predicted the temperature more accurately than the IPCC. This is an outright falsehood. In fact, Easterbrook had to distort the IPCC projection figures to make his graph compelling. Here is the actual data[3]: We see that the IPCC's projections were much more accurate. Shall we zoom in a bit more? Con then cites his first actual study, despite it being relatively insignificant, as it is a single study and has a largely negligent effect on the hockey stick graph. I'm now going to provide some consistent and substantiated data regarding the hockey stick graph.The hockey stick is describes a sharp increase in temperature visible within a reconstruction of temperatures in the last 1000 years. The original paper describing this trend appeared in 1998,but since then there has been a number of notable proxy studies that have confirmed its findings[4][5][6]. In 2007 an independent study reconstructed largely similar results, and evaluated the statistical techniques employed to create it[7]: Con's own graph was constructed from unknown data sets, presumably by NewsBusters, a questionable source (given their clear bias in documenting the issue). His next graph is also cited the same source, despite that graph not existing anywhere on the source page. I have no obligation to rebut something that has been pulled from thin air and not substantiated with fact, especially in supposedly scientific debates like this one.In his next argument, pertaining to water vapour, Con shows elementary misunderstanding of climate sensitivity and feedback. His argument can be summed up in the following format:P1: Water vapor makes up 95% of greenhouse gases and CO2 only . (Bare assertion)P2: The climate sensitivity of water vapour is around 0.25%. The climate sensitivity of CO2 is around 1%. (Disputable and unsourced, my Constructive Case hinted at a slightly higher figure between 2 and 4.5 degrees)P3: Global warming is occurring. (A sudden change of heart)C1: Water vapour is responsible for global warming,Before I begin tearing this nonsense apart I'd like to urge voters to hold Con accountable for changing advocacy half way through his case (in the same contention!). He first contends that there is no warming, and then holds that there is warming, only that water vapour is responsible. We aren't going to have quality discourse if Con does not hold a stable position.Con fails to understand that weak warming caused by more carbon dioxide will lead to more water vapor in the atmosphere, which will then amplify the weak warming through water vapor’s role as the atmosphere’s primary greenhouse gas. Water vapour is responsible for much of the greenhouse effect, but only because warmer air masses, on average, contain more water vapor. In short, water vapour acts a feedback, not a forcing[10]. Much of his further case was also preemptively rebutted in my initial constructive case: "Despite man made carbon dioxide emissions being comparatively smaller than natural emissions, the real driving force of climate change is the net quantity of carbon dioxide released, since most natural carbon emissions are absorbed[8]. Because of this, atmospheric carbon dioxide is at the highest levels in approximately 15 to 20 million years[9]."[1] http://onlinelibrary.wiley.com...[2] http://iopscience.iop.org...[3] http://www.skepticalscience.com...[4] http://www.meteo.psu.edu...[5] http://www.ncdc.noaa.gov...[6] http://www.ncdc.noaa.gov...[7] http://www.cgd.ucar.edu...[8] http://www.ipcc.ch...[9] http://www.sciencemag.org...[10] http://www.realclimate.org...R3:A single, self-described proponent of climate change being wrong, on a single instance, has no relevance to the ultimate scientific validity of climate change. This is hardly worth rebutting. Can we move discussion to the science, rather than people, and badly reported news stories?R4:Con argues that sea level rise has not occurred and cites Mörner, whose work has consistently been discredited by the organisations that he claims to represent:"Mörner claims that the "true experts" think this data is wrong (emphasis added): "The world’s true experts on sea level are to be found at the INQUA (International Union for Quaternary Research) commission on Sea Level Changes and Coastal Evolution (of which I am a former president), not at the IPCC. Our research is what the climate lobby might call an ‘inconvenient truth’: it shows that sea levels have been oscillating close to the present level for the last three centuries. This is not due to melting glaciers: sea levels are affected by a great many factors, such as the speed at which the earth rotates. They rose in the order of 10 to 11cm between 1850 and 1940, stopped rising or maybe even fell a little until 1970, and have remained roughly flat ever since." This is quite different from the INQUA official position on climate change, which opens by saying (emphasis added): Climate change is realThere is now strong evidence that significant global warming is occurring. The evidence comes from direct measurements of rising surface air temperatures and subsurface ocean temperatures and, indirectly, from increases in average global sea levels, retreating glaciers, and changes in many physical and biological systems. It is very likely that most of the observed increase in global temperatures since the mid-twentieth century is due to human-induced increases in greenhouse gas concentrations in the atmosphere (IPCC 2007)." [1] Unfortunately ounces up and down slightly from year to year so it's possible to cherry-pick data falsely suggesting the overall trend is flat, falling or linear. Credible sources will all display sea level averages over the long term. Here is a study done by the University of Colorado [2]: It shows a clear trend in sea level movement since 1995. Another study, analysing global mean sea level from 1870 through 2006 determined another clear trend[3]: [1] http://www.skepticalscience.com...[2] http://sealevel.colorado.edu...[3] http://academics.eckerd.edu...R5: Con has not provided a single relevant source, which, quite frankly, in an entirely statistical and scientific argument, is unacceptable. I cannot rebut imaginary data. Next round, please provide valid sources and explain their relevance, and I will take delight in rebutting them,ConclusionMuch of Con's argument has been founded on bare assertions and comprehensive misinterpretations of climate science. I have rebutted all his sourced claims, and hopefully cleared up much of his misunderstanding in regard to climate feedback.Onto the next round. Good luck, Con.