[1] Univ Loughborough, Dept Geog, Loughborough LE11 3TU, Leics, England
[2] United Nations Dev Programe, Pretoria, South Africa
[3] UK Govt Dept Int Dev, London, England
[4] Univ Cape Town, Climate Syst Anal Grp, ZA-7925 Cape Town, South Africa
[5] Met Off, Hadley Ctr, Exeter, Devon, England
[6] Univ Reading, Dept Meteorol, Reading, Berks, England