How to tackle the impacts of climate change is front and centre as world leaders, environmental activists, and concerned citizens young and not-so-young gather in New York, with the UN Climate Action Summit kicking off a week of debates and high-level meetings at the General Assembly on Monday. 

There’s a lot to discuss: A new study estimates that the number of people caught in humanitarian crises fuelled by climate change will nearly double if countries fail to limit rising global temperatures – inaction that could also cost billions in humanitarian responses.

The report, from the International Federation of Red Cross