Cop29: what are carbon credits and why are they so controversial?

Once heavily scorned because of fraud and poor outcomes, carbon trading is likely to be high on the agenda in Baku

For the next two weeks, countries will gather on the shores of the Caspian Sea in Baku, Azerbaijan, to discuss how to increase finance for climate crisis adaptation and mitigation. A global agreement on carbon markets will be high on the agenda as countries try to find ways of generating the trillions they need to decarbonise in order to limit heating to below 2C above preindustrial levels.

Here is what you need to know.