Credit where credit is due, Matt Yglesias coined the phrase "climate cliff" via Twitter the other day in reference to the now inevitable 2°C global temperature increase. I liked it so much I thought I'd borrow it for a while.
Why a cliff? On the other side of this 2°C threshold, designated by the EU in 1996 and reinforced this month at the climate conference in Doha, Qatar, are unspeakably disastrous consequences. The 2°C (3.6 degrees Fahrenheit) breaking point indicates the total temperature increase from pre-industrial records. Since then, however, greenhouse gasses have already generated a 0.8°C hike. In other words, we're nearly halfway there.
Worse yet, the CO2 we're emitting right now will create another 0.7°C of additional inevitable warming. So we're really just 0.5°C away from falling over the cliff. As recently as two years ago, scientists placed the cliff at the year 2100, but since then, it's become clear that we'll hit the cliff much sooner, by around 2052.