Volcanoes or what?
BlackFireNova is wrong and Klassman is right about CO2 emissions from volcanoes. The annual rate of CO2 from volcanoes is insignificant compared with the current rate of man-made CO2 emissions. This is a feeble argument usually put out by uninformed climate skeptics.
What is true, however, is that the rate of man-made CO2 emissions rate is miniscule (only about 2%) when compared with the rate at which the environment as a whole puts CO2 into the atmosphere (predominantly from from decay of vegetation.
However, had you made your same point using that correct statistic, you would still have been challenged on the grounds that the natural emissions are balanced by natural carbon sinks (predominantly the uptake of CO2 by vegetation). So the argument goes that, since the natural ocean-atmosphere CO2 cycle is balanced, only the additional unnatural man-made CO2 emissions from fossil fuels should be counted towards the accumulation of CO2 in the atmosphere expected over the next century.
But the trouble with that argument is that the amount of CO2 retained in the atmosphere isn't actually related to the net CO2 flows in or out anyway! It is only related to the water temperature and hence the solubility of CO2. So the rise in ocean temperature that has occurred over the past 250 years could be due to a combination of natural causes and the supposed warming effect of man-made CO2, the problem being to determine the proportionate contribution of each source.
Hence the ongoing debate which is far from settled.
