"Conservative" is a somewhat meaningless term in this context. On one hand, it's conservative to continue with business as usual and ignore potential problems u

"Conservative" is a somewhat meaningless term in this context. On one hand, it's conservative to continue with business as usual and ignore potential problems until they become unavoidable. However, it would also be conservative to keep CO2 levels in the atmosphere at their current levels, instead of running a radical climate experiment in which they are pumped up to ever higher levels.