As Paris recovers from the terrorist attacks, leaders will gather to negotiate a new global climate treaty. There are still plenty of potential sticking points - but hope remains high for a meaningful result.
Money will be a big topic at the upcoming climate summit talks in Paris. Countries are negotiating who will pay for climate safety measures, how much money will be on the table, how to raise it - and how to spend it.
As politicians debate how to halt the warming of the planet, some 200 years of climate science sets the basis for all this fuss. But this science hasn't always been a given.