The human effect on global warming is significant.

He begins by saying that a significant cause does not need to be 50% or more to be important or significant. He validates this by saying "If a cause is important, it means that the outcome would have been noticeably different had that cause not existed" Yet I can similarly refute this by saying that human emissions are not important because if it were non existent, we would have only seen a 3-4% decrease in global warming. Hardly significant at all. This brings me on to the next point where the opponent asks to see the evidence. The evidence is here: http://www.geocraft.com... (the graph is near the bottom, also this is not the actually scientific article, this is a site hosting the graph) And also, I made a minor misquoting of the evidence, CO2 is 3.618% of the cause not 3.502% I apologize for the inconvenience yet the percentage is still incredibly small. Now my opponent then states that CO2 essentially acts as an amplifier for the global warming effects making the effects even worse. He warrants this with an article from realclimate.org. His validation is wrong for 2 reasons 1)No where in the article does it say that it is because of humans that global warming intensified. Rather it states that the CO2 "might be stored in the deep ocean during ice ages, and then get released when the climate warms" Therefore the article my opponent uses directly counters his own side. The reason for this is that my opponent has the burden to prove that humans are the greatest cause of global warming. The article not only states that the changing patterns of sun shine may be a cause of GW, yet the CO2 rise is mostly due to the CO2 stored in the oceans, not humans. 2)His article assumes that there will be a significant amplification of the effects of global warming due to CO2 from the abundance of trapped CO2 in the ocean. However if he uses the same reasoning in the article to apply it to the CO2 from humans as opposed to the CO2 in the ocean, it will still not be true. The reason is that because CO2 from humans is so low, 3.618%, the amplification of the effects is similarly going to be incredibly small. No where in the opponents' first two articles does it state that humans are the main cause of increases in CO2. My opponent then states that human emissions must be the cause of global warming because there is no other variable other then human emissions. I have 2 responses to this. 1)Human emissions are not the only variable. In the Alps, scientists have conducted research and they found that the level of water vapor increased by 4% corresponding to an increase in one degree of temperature. Therefore water vapor is another variable and there has been shown a link between vapor and warming. 2)Human emissions do contribute to global warming, yet the effect is so miniscule that it does not demonstrate a significant cause for global warming. My opponent then questions why using a democratic scale is biased. The reason is that simply saying that many scientists agree that global warming is caused by humans does not mean that it is true. What's more important is that my opponent is painting the wrong picture for you. He is making it seem like 99.9999% of all scientists think humans are the cause, yet that is simply not true. I could similarly show you that many institutions and agencies also believe that global warming is caused by other factors not humans. MIT, JSER (backed by Japan's leading scientists), Professor Lance Endersbee, Prinicipal Research Scientist, Spencer of the University of Alabama… and the list goes on. What you see is that there are scientists on both sides arguing whether humans are or are not the cause. Therefore if there are scientists and agencies that are arguing that humans may not be the cause of global warming, we can't just assume that these scientists are wrong and these scientists are right and we must instead look to the facts behind why it is so instead of seeing the stances of different scientists. Also in response to the quote from the blog, sorry I did a cursory reading of the article and thought that the excerpt from an MIT article was actually part of the real article, so I thought it was scientific. Yet I will drop this quote in this debate. And now my opponent brings up the point of the consensus view of global warming caused by humans in these scientific articles. Yet again, there are also articles stating the opposite. The JSER (the energy agency of Japan), for example, did an extensive study and found that humans are NOT the cause of global warming. Because my opponent has not brought any counter evidence to my evidence of water vapor being 95% of the cause of global warming, this point can flow through. He also brings up the point that consensus among scientists is more accurate than consensus among the general population however: 1)All of the laws of physics was a consensus among physicists, yet string theory later proved some false. 2)There are also scientists that believe that humans are not the cause of global warming. Now you should vote for the negation for 3 reasons 1)My opponent still has not brought up counterevidence stating CO2 is the main cause of global warming, Thus his first contention falls. 2)My opponent still has not validated why the scientists saying global warming is caused by humans are supposedly more credible than the Energy department of Japan or MIT. Therefore if he cannot show why we must agree with only those scientists, and not some others, then his second contention falls. 3)I have brought up the relevant evidence proving my points while my opponent lacks counter evidence. Also sorry if you thought I was lying about the quote, but I misread the article and assumed it was scientific, but I will drop that point in this debate.