Geography of Ethiopia - Climate

Climate

The climate is temperate on the plateau and hot in the lowlands. At Addis Ababa, which ranges from 2,200 to 2,600 m (7,218 to 8,530 ft), maximum temperature is 26 °C (78.8 °F) and minimum 4 °C (39.2 °F). The weather is usually sunny and dry, but the short (belg) rains occur from February to April and the big (meher) rains from mid-June to mid-September. The climate of Ethiopia and its dependent territories varies greatly. The Somali Region and the Danakil lowlands in the Afar Region have a hot, dry climate producing semi-desert conditions; the country in the lower basin of the Sobat is hot, swampy and malarious. But over the greater part of Ethiopia as well as the Oromia highlands the climate is very healthy and temperate. The country lies wholly within the tropics, but its nearness to the equator is counterbalanced by the elevation of the land. In the deep valleys of the Tekezé and Abay, and generally in places below 1,200 m (3,937 ft), the conditions are tropical and diseases such as malaria are prevalent. In the uplands, however, the air is cool and bracing in summer, and in winter very bleak. The mean range of temperature is between 15 to 25 °C (59 to 77 °F). On the higher mountains the climate is Alpine in character. The atmosphere on the plateaus is exceedingly clear, so that objects are easily recognizable at great distances. In addition to the variation in climate dependent on elevation, the year may be divided into three seasons. Winter, or the cold season, lasts from October to February, and is followed by a dry hot period, which about the middle of June gives place to the rainy season. The rain is heaviest in the Tekezé basin in July and August. In the former provinces of Gojjam and Welega heavy rains continue till the middle of September, and occasionally October is a wet month. There are also spring and winter rains; indeed rain often falls in every month of the year. But the rainy season proper, caused by the southwest monsoon, lasts from June to mid-September, and commencing in the north moves southward. In the region of the headwaters of the Sobat the rains begin earlier and last longer. The rainfall varies from about 750 mm (29.5 in) a year in Tigray and Amhara to over 1,000 mm (39.4 in) in parts of Oromia. The rainy season is of great importance not only to Ethiopia but to the countries of the Nile valley, as the prosperity of the eastern Sudan and Egypt is largely dependent upon the rainfall. A season of light rain may be sufficient for the needs of Ethiopia, but there is little surplus water to find its way to the Nile; and a shortness of rain means a low Nile, as practically all the flood water of that river is derived from the Ethiopian tributaries.