Steven Sherwood (in a Science letter), with respect the urgency for action in response to global warming:

Greater urgency comes from the rapid growth rate (especially in the developing world) of the very infrastructure that is so problematic. Mitigating climate change is often compared to turning the Titanic away from an iceberg. But this "Titanic" is getting bigger and less maneuverable as we wait--and that causes prospects to deteriorate nonlinearly, and on a time scale potentially much shorter than the time scale on which the system itself responds.