Rainfall in East Africa

Key messages:

  • Under a +2°C and a +3°C global warming, a slight decrease in precipitation is projected over Ethiopia, whereas, an increase in precipitation is projected in West Sudan and across Somalia
  • There is a modest consensus among the analyzed simulations

Why is the content of this map important?

The increase in temperature will be 1.5°C to 2°C over Ethiopia and Somalia, and 2°C to 2.5°C over Sudan. This implies a significant increase in evaporation. The fact that precipitation stays at the same level, in view with increasing evaporation, implies rising shortages in water resources.

Which sectors are affected by this result?

The water shortage will affect the agriculture and hydrology sectors. 

What is shown on the maps?

Along the Somalia coast, rainfall increases by 60 mm per year, for a present amount of 400 to 800 mm/year from North to South. Over the Ethiopian plateau, rainfall response is -20 mm on average, though the model responses spread from -60 to +20 mm. In West Sudan, an increase of rainfall is projected from 0 to 40 mm from North to South relative to the amount (about 200 to 1000 mm/yr) during the reference period. This triple pattern of increase over Sahara and Somalia and decrease along the Nile valley is found also with the +3°C global warming.

Details and further information:

This table shows that the precipitation increase concerns the autumn rains.

Monthly accumulated precipitation over land (mm)
  J F M A M J J A S O N D
1971-2000 30 32 53 81 77 66 85 98 85 76 60 38
+2°C 30 32 53 80 75 64 84 101 88 81 64 39


Additional information:

The climate change indicators have been calculated from the CNRM/CNRM-ARPEGE52,CNRM/ENEA-REGCM, ECEARTH/CSC-REMO, ECEARTH/SMHI-RCA4, ECEARTH/DMI-HIRHAM, MPI-ES/CSC-REMO simulations.


Michel Déqué

Meteo France (MeteoF), France