For today’s inconvenient truths (ahem), we turn to Kevin Anderson, a professor of energy and climate change who was, until recently, director of the U.K.’s leading climate research institution, the Tyndall Energy Program.
This year, with his colleague Alice Bows, he published a paper called “Beyond ‘dangerous’ climate change: emission scenarios for a new world” [PDF].
Let’s walk through Anderson’s logic.
[I]f we delay the global emissions peak until 2025, we pretty much have to drop off a cliff afterwards to avoid 2 degrees C. Short of a meteor strike that shuts down industrial civilization, that’s unlikely.
How about 2020? Of the available scenarios for peaking in 2020, says Anderson, 13 of 18 show hitting 2 degrees C to be technically impossible. (D’oh!) The others involve on the order of 10 percent reductions a year after 2020, leading to total decarbonization by 2035-45.
This, then, is the brutal logic of climate change: With immediate, concerted action at global scale, we have a slim chance to halt climate change at the extremely dangerous level of 2 degrees C. If we delay even a decade — waiting for better technology or a more amenable political situation or whatever — we will have no chance.
It might seem that, given the extraordinary difficulty of hitting 2 degrees C, we ought to lower our sights a bit and accept that we’re going to hit 4 degrees C. It won’t be ideal, but hitting anything lower than that is just too difficult and expensive.
The thing is, if 2 degrees C is extremely dangerous, 4 degrees C is absolutely catastrophic. In fact, according to the latest science, says Anderson, “a 4 degrees C future is incompatible with an organized global community, is likely to be beyond ‘adaptation’, is devastating to the majority of ecosystems, and has a high probability of not being stable.”