tonnes
tonnes is a funny word. i think it mean 1000 kg. anywho, all previous caveats aside i ran some numbers checking some claims by other blogs that undeniably publish unsubstantiated garbage. anywho, the assertion is that human emission of co2 is insignificant. okay. the numbers. there are some 3,000 gigatonnes (an even funnier word) of co2 in the atmosphere. people toss some 2-3 gigatonnes into the air burning fossil fuels each year. i made some swags (scientific wild assed guesses) at a total since the beginning of the industrial revolution. and came up with 180 gigatonnes. which is some 6% of what's in the atmosphere. 6% is a small number. but it's not insignificant. atmospheric co2 has risen some 35% over that time period. of which our 6% contribution may be a significant part. also means that burning fossil fuels alone doesn't account for all of the change. the other major contributors would be: changing land use, warmer sun, dust, and feedback.