The aid sector loves its acronyms. Mix in some climate science and the political language of global treaty negotiations, and you have a recipe for a (rapidly heating) pot of alphabet soup. Here's our updated guide to some language abbreviations, acronyms and initialisms that help make the language of climate change a little more concise, if not entirely clear.

We also mix in some key concepts that underlie climate action and summit negotiations. (Irwin Loy, Will Worley, more at thenewhumanitarian.org)