All the hype about CO2 is missing the big picture IMO... sure, we (that is, humans) produce a lot, but not nearly on the scale as the world's volcanos. What we should really be worried about is methane... its global warming effect is apparent at about 1/25th the scale of CO2 (meaning, you need 25 parts CO2 to see the same warming effect as 1 part methane) "According to a 2006 report by the U.N. Food and Agriculture Organization, the livestock industry is one of the top three contributors to the planet's most serious environmental problems. Cows and other livestock (such as pigs, sheep and goats) release methane gas when they burp or fart, making them responsible for 18 percent of the world's greenhouse gas problem. It's estimated that a single cow can produce 25 to 130 gallons of methane a day. In addition, nearly 30 percent of the available land on the planet is used for grazing livestock and growing their feed -- often at the expense of forests -- and their manure is a major source of water pollution and acid rain." "Methane levels rose last year for the first time since 1998. Methane is 25 times more potent as a greenhouse gas than carbon dioxide, but there’s far less of it in the atmosphere—about 1,800 parts per billion. When related climate affects are taken into account, methane’s overall climate impact is nearly half that of carbon dioxide." http://www.sciencedaily.com/releases/2008/04/080423181652.htm What you should REALLY be scared about? There's a mega-shitton of peat out in Siberia that is so full of methane that it is literally bursting out of the permafrost. When that stuff starts to really melt, we are really fucked. Sorry, but I had to bust out the srs. You did ask for a discussion, after all.
yeah, tundra explosions will continue to increase across the arctic... the biggest issue isn't how much we do but how we do it. we've taken away from the land and oceans much of its capacity to handle CO2 or simple hydrocarbons. we have a lot of programs designed at reversing the shift in plant life, but at this point, it's really only slowing down things instead of reversing them. hopefully we can continue to progress (and diet at the same time)