This would probably be a good point to add that the only way we feed our large population now is through intensive, petroleum-based, monoculture agriculture. At our current population levels we are trapped in a situation where implementing sustainable, net-zero carbon-emission agriculture would result in mass starvation.

Yet continuing to pump massive amounts of carbon into the atmosphere is also going to cause enormous suffering. Quite the catch 22. Plenty of experts say the only way to break that cycle is to reduce the human population.