The general precipitation image of Ethiopia (and Eritrea) is characterized by the highland (with high precipitation) - lowland (with low precipitation) situation, with transition to tropical high-rainfall regions in the SW and the escarpement on the W side of the rift valley, which attracts the monsoounal humidity from NE. While the annual mean rainfall appears to be sufficient for agriculture in many parts of Ethiopia (and Eritrea), it is more the unreliability (high standard deviation), which forms a problem for the agriculture.

0 - 300	300-600	600-900	900-1200	1200-1500	1500-1800	1800-2100	> 2100
mm Precipitation per Year (Colors might differ due to monitor settings and selected transparency)

         

The first, general step in the land evaluation and land use planning procedure is a small-scale, often nationwide resource inventory to assess the general potential and to select a suitable site with potential for further evaluation, surveys and later planning and investment. At the Land Use Planning and Regulatory Department / Project, this nationwide survey was used to select the actual planning sites for agricultural improvements. (Actual source: Mesfin Wolde Mariam: An atlas of Ethiopia)

See another small-scale survey of Ethiopia: Temperature
and the more detailed inventories in project areas of Borkena ( land use, soils) and of Bichena ( soils)