This week’s summit will focus on paying for the costs of global heating – and much more money is needed

About 50,000 government officials, policymakers, investors and campaigners will gather in Azerbaijan this week in the hope of answering a trillion-dollar question: how much money should go each year to helping developing countries cope with climate-related costs?

The aim of the UN’s Cop29 climate talks in Baku, which is being called the “climate finance Cop”, is to establish a new annual climate financing target to replace the current $100bn pledge, set in 2009, which expires at the end of this year. There is one clear consensus already: the existing climate finance available to developing countries is nowhere near enough to withstand worsening climate impacts. The ambition is too low, and in 15 years the annual target has been met in full only once, in 2022.