This is evident from the increasing greenhouse gas...
Anthropogenic Climate Change Exists
My opponent claims that the "climate competitors" of CO2 account for an unknown portion of temperature anomaly. We actually have a comprehensive understanding of both chemical and physical factors of climate change. He is correct that if we compared a chart of barbecue emissions with a chart of atmospheric heating, it would be absurd to assume barbecuing causes global warming. However, if we measured the effects of shortwave radiation, longwave radiation, the manner in which each passes through clouds, the effects of vegetation, the net greenhouse effects of the oceans, and emissions of non-barbecuing greenhouse gases, we would be in a much better position to say whether barbecue emissions cause global warming. [5] Con correctly argues that the barbecue theory would be defeated by showing that the volume of charcoal is insufficient. So back to the discussion, what's the volume of CO2 output? The United States alone has a crude oil energy output of 19,420,000,000,000,000 British Thermal Units [6]. Is this comparable to backyard barbecues? [5] The fifth report by the International Panel of Climate Change [7] claims that "Human influence on the climate system is clear. This is evident from the increasing greenhouse gas concentrations in the atmosphere, positive radiative forcing, observed warming, and understanding of the climate system." It presents evidence that the CO2 output of fossil fuels and anthropogenic land usage together total are nearly three times higher than the CO2 output of rock weathering, volcanic activity, total respiration of life forms, forest fires and freshwater outgassing combined. [5] Con offers a reconstruction of the last 650,000,000 years, but this is a discussion about the years 1900 to 2200. Geological time is slow enough to be irrelevant in the 3-century blip we are discussing. In this context, hundreds of millions of years is simply beyond a defensible scale. CO2 levels are not higher than what they were 100,000,000 years ago before the existence of humans, but they are higher than they have been in 400,000 years. "Current climate science has no explanation for the major climate variations of the past 2,000 years." I have BOP for my claims about modern climate observations, but Con needs to provide a source for this claim. "That's why the discredited global warming hockey stick attempted to prove there were no past variations." Source and specifics would be appreciated. Con claims that CO2 follows temperature rather than causing temperature, claiming the graphs are in a link. I would appreciate if Con could import these graphs into DBO and reference them as individual images, as I am unable to find an image that matches this description in the link provided. The Nature article quoted by Con demonstrates that solar insulation changed the Earth's climate more in 2,000 years than the human race has in 250 years. It does not suggest that the factors it discusses could compete with the human race during industrial and post-industrial ages. Again, this is a discussion about a 300 year timespan. [5] "Historically, Arctic ice melts when Antarctic ice increases in a cycle of 40 to 60 years called the Pacific Decadal Oscillation (PDO)." The Pacific Decadal Oscillation has no relation to the absorption of energy by the oceans from the years 1970 to 2010, which have shown a strong increase in net energy both in the liquid oceans and in the polar ice caps. “The Antarctic surge is so big that overall, although Arctic ice has decreased, the frozen area around both poles is one million square kilometres more than the long-term average.” Both Arctic and Antarctic temperatures are supposed to be far below freezing, and neither will commence a serious level of shrinking until they reach the melting temperature of water. As the top of the ice caps melt, the water runs down and is cooled by the ice below, slightly reducing or maintaining the total mass of the ice while possibly increasing the total area. However, it also increases the average temperatures of the Antarctic and Arctic. 5. http://www.climatechange2013.org... 6. http://www.usdebtclock.org... 7. http://www.climatechange2013.org...