International climate finance – funds provided or leveraged by richer countries to support climate mitigation and adaptation measures – has traditionally been one of the most important elements of negotiations at UN climate change conferences. Climate finance is needed to significantly reduce emissions, but donor countries have been hesitant to commit. At COP15 in Copenhagen in 2009, developed countries promised to mobilise 100 billion US dollars from public and private sources per year by 2020 for climate change mitigation and adaptation in developing countries – but they failed…