When Advance Aid was in Nairobi at the end of September the grass almost everywhere was brown and the Masai were bringing their cattle into the centre of the city in search of grass verges that might have been watered that the painfully thin cattle could feed on.

Now there are floods as the country goes, almost overnight, from too little to too much water.  The same story is being repeated in Somalia, on the border with Kenya, where 15,000 people in the town of El-Waq are reported to have been displaced by floods.

And today Sir Gordon Conway, Professor of International Development at Imperial College, London, is arguing that Africa is already warming faster than the global average and that people living there can expect more intense droughts, floods and storm surges.

His Discussion Paper No 1 published by Imperial College’s Grantham Institute for Climate Change suggests that:
• The drier subtropical regions will warm more than the moister tropics.
• Northern and southern Africa will become much hotter (as much as
4 °C or more) and drier (precipitation falling by 15% or more).
• Wheat production in the north and maize production in the south
are likely to be adversely affected.
• In eastern Africa, including the Horn of Africa, and parts of central
Africa average rainfall is likely to increase.
• Vector borne diseases such as malaria and dengue may spread and
become more severe.
• Sea levels will rise, perhaps by half a metre, in the next fifty years,
with serious consequences in the Nile Delta and certain parts of
West Africa.

The humanitarian consequences of these types of changes are very clear.  And very worrying.