No consensus at the UN: CO2 may cause African crop yields to drop by 50%, or maybe Africa will feed the entire world

2010:  African crops yield another catastrophe for the IPCC - Telegraph

One of the most widely quoted and most alarmist passages in the main 2007 report was a warning that, by 2020, global warming could reduce crop yields in some countries in Africa by 50 per cent. Dr Pachauri not only allowed this claim to be included in the short Synthesis Report, of which he was co-editor, but has publicly repeated it many times since.

'Africa can feed the world' | Mark Tran | Global development | guardian.co.uk

Africa can feed not just itself but the world is a bold assertion to make at a time when famine stalks part of the continent.

But this is precisely the claim made by Kanayo Nwanze, the president of the International Fund for Agricultural Development (Ifad), a specialised agency of the UN.