It’s Paris or bust. Climate diplomats are preparing for a United Nations climate conference in the French capital in December that scientists say is probably the last realistic chance for the world to prevent global warming going beyond 2 degrees Celsius. Some kind of a deal will probably be done. But will it be one more diplomatic fudge or a real triumph for the climate? In the run-up to Paris, governments have been asked to deliver pledges to cut emissions of the greenhouse gases known to cause climate change. The pledges, covering the period between 2020, when the agreement should enter into force, and 2030, are known as Intended Nationally Determined Contributions, or INDCs in the U.N. jargon.