The Paris agreement will not stabilise the climate; but the efforts it makes possible could still achieve a lot.
“The test of a first-rate intelligence”, F. Scott Fitzgerald, a sometime Parisian, once wrote, “is the ability to hold two opposing ideas in mind at the same time.” By this standard, the 195 countries that gathered outside Paris in the two weeks running up to December 12th to negotiate a new agreement on climate change have to be counted very bright indeed. It is vital, they declared, that the world’s temperature does not climb much more than 1.5°C above pre-industrial levels; and yet they simultaneously celebrated a new climate agreement that got nowhere close to preventing such a rise.
The individual pledges that nations made going into the Paris talks—which they will now be expected, though not compelled, to honour—are estimated to put the world on course for something like 3°C of warming. In the non-linear universe of climate change, 3°C represents a lot more than twice as much risk and harm as 1.5°C; it could well, for instance, be the difference between the Greenland ice cap staying put and the sea-level rising, over centuries, by six metres.
The Economist