Global warming is likely (and mostly) anthropogenic

Correlation and Causation Pro claims, “The more robust the correlation, the more likely some causation exists.” This is blatantly false. The stronger the correlation the stronger the relationship, but it does not prove one thing caused the other. In order to prove causation, you need to prove that CO2 preceded the warming. Pro also claims that CO2 in the atmosphere amplifies temperatures through the greenhouse effect. In actuality the cooling effect of CO2 is far greater than the heating effect. CO2 is commonly used as a refrigerant, due to its natural cooling properties. According to physicist Dr. Charles Anderson, “the cooling effect due to keeping incoming solar IR radiation away from the surface is about 100 times the re-heating effect proclaimed by greenhouse gas alarmists”. [1] When you talk about greenhouse gasses, you need to remember that ozone or O3 is a greenhouse gas. The Ozone protects the earth from the sun, thereby cooling the earth. A study conducted by NASA has found that CO2 and N2O block up to 95% of solar rays, thereby reducing the global temperature. [2] Correlation strength My opponent had tried to make the claim that correlation between CO2 and Global temperatures is strong, when in reality the correlation is poor; it is just short of being fair. The coefficient of determination, R2, of CO2’s relation to USHCN2 surface temperature is only 0.44. [3] When USHCN2 surface temperatures are plotted against solar activity, it shows a much greater relationship; while it is only a fair correlation, it has an R2 of 0.57.[3] The correlation between surface temperatures and the temperatures of the Atlantic and Pacific oceans are much stronger, with an R2 of 0.83. [3] Oceans cause the CO2 rise My opponent tries to refute this with the claim that CO2 levels are unprecedented. The current CO2 levels are 398.35 ppm. [4] 2 million years ago CO2 levels was 300 ppm, 100 million years ago it was 1,200 ppm, and 540 million years ago it was as high as 7,000 PPM. [5] There is nothing unnatural about CO2 levels. CO2 levels have been pretty stable for the last 2 million years compared to earlier eras. [5] Pro claims that humans are responsible for 16 billion tons of CO2 in the atmosphere and 14 billion tons of CO2 in the ocean. Once again, there are 720 billion tons of CO2 in the atmosphere, and there are 36 trillion tons of CO2 in the Ocean. Thus Humans would only be responsible for 2% of CO2 in the atmosphere, and 0.04% of CO2 in the ocean. Pro tries to claim that because rises in CO2 preceded the end of the ice age, that CO2 caused the end of the ice age. First off, there has always been controversy over which came first during the ice age melt. The most comprehensive study to date came out in 2013. Using EPICA ice cores, they tracked CO2 records back 800,000 years. The study found that between 20,000 and 10,000 years ago, CO2 levels lagged global temperature by up to 1,400 years. [6] Trends My opponent has attacked my graphs claiming they were exaggerated without providing any evidence for exaggeration. Pro also claims that the medieval warming period was a local event. There has been evidence found in Antarctica, proving that the medieval warming period was global not local. [7] Other than these points, Pro’s points are addressed in my other arguments, and Pro has ceded that climate change is a natural phenomenon. The sun My opponent tries to claim that solar activity as decreased since the 60’s. In actuality solar activity has remained relatively constant, while the intensity of solar radiation has increased by 0.05% per decade. In their report, NASA concluded that "This trend is important because, if sustained over many decades, it could cause significant climate change". [8] The Atmosphere Pro claims that the greenhouse gases that make up the atmosphere warms the earth, when in reality it protects the earth from the sun. [2] Other points All other points made by pro have been covered and/or made irrelevant by my above arguments. Conclusion The correlation between CO2 and temperature is too week to claim one causes the other; a wide variety of natural factors determines the level of CO2 in the atmosphere. A majority of the CO2 in the atmosphere is natural. CO2 causes more cooling than warming. The main cause of global temperatures is the sun, which has increased in intensity. CO2 lagged behind temperature when the ice age ended. http://hockeyschtick.blogspot.com... http://principia-scientific.org... http://wattsupwiththat.com... http://co2now.org... http://www.ei.lehigh.edu... http://www.scientificamerican.com... http://scienceandpublicpolicy.org... http://www.nasa.gov...