The international aid agency Oxfam says climate change is set to cause hunger on a scale that'll make it the defining human tragedy of this century.
A report, released ahead of this week's G8 summit, says poor people in the developing world are being further impoverished, as unpredictable weather patterns lead to more natural disasters and falling crop yields.
It urges G8 leaders to cut carbon emissions by at least 40% from 1990 levels by 2020, and to provide $150bn to help poorer nations adapt.
Shorbanu Khatun is a widowed farmer and fisherwoman from Bangladesh who lost her home and her livelihood in a cyclone.
Oxfam brought her to Britain to take part in a campaign against the building of a coal-fired power station outside London. Alex Renton authored the report.
First broadcast 6 July 2009