Terrain shapes and bedrock
According to COUNTRYAAH, Ethiopia has the largest contiguous elevation area in Africa and a distinctive topography. This is mainly related to the country’s location at the large East African fault line (the rift). Ethiopia can be divided into three main geographical regions.
The Rift Valley, which is part of the East African Rift system, is a tectonically formed sink that runs through the country in its longitudinal direction. It separates the other two main regions and also covers most of the coastal zone towards the Red Sea. The Rift Valley is 40-60 km wide and runs from the border with Kenya to the northeast. It contains a large number of lakes, from south Chew Bahir, Abaya, Awasa, Shala, Langeno, Abiyata and Ziway. After 600–700 km from the border, the valley widens and forms the Awash basin with the river Awash. Here, the low area takes the form of a triangular lowering field called the Afar sinkand to a large extent occupied by the Danakila desert. The lowest point is the Kobar sink (116 meters below sea level). The entire area is old seabed and has slipped from its original location adjacent to the southwest tip of the Arabian Peninsula.
The western highland region lies west of the major fault and has an altitude of 2,400-4,000 meters above sea level. It consists of large rock masses, plateaus and deep, canyon-like erosion valleys. The largest mountain massif lies south of the Tigray plateau and includes Lake Tana to the south. In the massif is the Simen Mountains with the highest peak in Ethiopia, Ras Dejen (4,620 meters above sea level). The area is made up of horizontal tertiary tuff and basalt layers. The plateau surfaces are separated by deep ravines and canyon valleys, the largest of which is the Blue Nile valley.
The southeastern highland region lies east of the rift valley and is also made up of tertiary basalt layers. The Arsi – Bala massif in the southern part has several high peaks, of which Batu reaches 4,307 meters above sea level. Large flat areas are spreading towards the border with Somalia.
The ground cover in Ethiopia has very different thickness and quality. It has been thinned heavily on the many slopes in the country through wear and erosion. The dominant soil is weathering soil, which is mainly derived from basalt and is nutritious, as are the alluvial deposits in the river valleys. Soils with a high content of clay are difficult to root as they burst during the dry season and become strongly sticky during the rainy season. In the higher parts, the often reddish soils provide an excellent basis for growing coffee, for example.
According to BRIDGAT, Ethiopia is completely within the tropical zone, but due to the country’s high position, the climate is temperate in several places. Another consequence of the altitude is the large diurnal variation in temperature; in Addis Ababa it averages 32 °C. The annual amplitude of the temperature, on the other hand, is low; for Addis Ababa 3.2 °C and for Mitsiwa (Massawa) 9.3 °C. There is a large temperature difference between highland and lowland areas. Addis Ababa has 16 °C while Mitsiwa has 31 °C in annual average temperature. The warmest month is generally May and coldest December.
The rainfall also varies greatly in the country and is tied to one or two rainy seasons. The rainy winds emit their moisture as they rise over the highlands of southwestern Ethiopia, where the rainy season lasts from June to September and yields 2,500 mm per year. Winter rain falls to a very small extent along the Red Sea coast. The rain often falls as heavy thunderstorms immediately after the dry season, when the ground is unprotected. This results in large losses of soil through erosion.
The cool and humid highlands of the west were up to 3,000–3,500 m in height originally covered by forests, while the warm and dry lowlands of the east housed, and still do, more economical vegetation, from dry savannas with acacia species and large-scale plants of the genus Euphorbia to the pure desert. The natural vegetation of the mountain forests is at lower altitudes tree water and dry forests, in some places (on volcanic ground) lush deciduous forests with fig species, palm trees and ferns. These are replaced at a higher altitude by a forest-forming, tree-shaped one, Juniʹperus proceʹra (sometimes called African cedar), mixed with, among other things. koso, brown olive (Oʹlea africaʹna) and the conifer tree Podocaʹrpus graciʹlior. The species of Arabic coffee, which is a shrub, grows wild here. Above about 3,000 m in height, a tree-shaped St. John’s wort and tree grove. Above the tree line are found grassy grasslands with giant lobelias (Lobeʹlia rhynchopeʹtalum and Lobelia gibeʹrroa) and the plant genus, which is often found in either northern or southern temperate regions.
Nature in Ethiopia is one of the most enlightened of man in all of Africa. The highlands are particularly affected, and especially in the northwest, all original forests are completely gone, with severe erosion damage as a result. Tree planting experiments are mainly done with eucalyptus species, especially in the central parts, e.g. around Addis Ababa.
Ethiopia’s more widespread mammal species include gold shawls, spotted hyena, streaked hyena, caracal, honey badger, warthog, bushbuck, rocker, rock digger, ground pig, anubis baby (Paʹpio anuʹbis) and green market. In addition, there are African elephant, hyen dog, hippopotamus, giraffe, larger kudu antelope (Trageaplaphus strepsiʹceros), oyx, African buffalo, common zebra and grevysebra (Eʹquus greʹvyi), mantle baby (Paʹpio hamaʹdryas) and eastern black and white (Guacia black) The three big cat animals are lions, leopards and cheetahs but are all rare. Tip rhinos are probably completely extinct.
In the highlands, there are four endemic, larger mammals: gelada (a baboon), mountain nyala (Trageʹlaphus buxtoʹni), Abyssinian shawl (Caʹnis simeʹnsis) and Abyssinian capricorn (Caʹpra waʹlie; sometimes counted as a subspecies to capricorn).
Among the birds are African ostrich, lambs, Rüppell’s vulture, chess (Buʹteo rufofuʹscus), white- necked raven and several species of stonefish. In the south-west are a number of East African birds. The country has 23 endemic bird species. Nile crocodile is still found in some rivers.
In 2012, Ethiopia had 13 national parks, among them Awash with several antelope species, the Baleberg national park with 32 species of mammals such as mountain snail and Abyssinian shale, Omo in the southwest with many large mammals, and Simenbergen national park, a highland area with, for example, Abyssinian beak and Abyssinian shale.