Latitudinal location of east Africa. Latitude refers to the distance from the equator. East Africa lies along or astride the equator at approximately 5 degrees north and south of the equator. For this reason, whether the apparent overhead sun shifts north or south, the angle of incidence of the solar rays is still small. So the sun rays strike the earth’s surface at a wide angle and at a short distance hence ensuring maximum solar heating throughout the year. This implies that the temperatures in east Africa are high throughout the year. Therefore, its only in highland areas which rise above the snowline where temperatures drop to below freezing point that enables glaciers to form. However, these are very few areas where temperatures can drop below zero degrees hence limited coverage.
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Altitude. East Africa lies on a raised plateau rarely rises above 3000m above sea-level. So very few areas in East Africa rise to the current snowline of 4800m above sea level hence the limited coverage of glaciers in East Africa.
Precipitation. East Africa generally receives moderate rainfall of between 1000 to 1500m per annum. This is just sufficient to sustain life. However, glaciers form in areas where temperatures drop below freezing point and with torrential rainfall.
Mountain Rwenzori has the highest number of glaciers although it’s the shortest among the three glaciated mountains in east Africa. However, it receives cool moist winds from Congo basin and the Atlantic Ocean which are forced to rise, cool and condense to form clouds hence giving torrential rainfall and very low temperatures hence glacier formation.
The highest is mountain Kilimanjaro but with the smallest coverage of glaciers due to the influence of the warm dry winds which brings about a warming effect and low rainfall.
Global warming. The world temperatures have been rising with time and this is attributed to human activities like burning fuels e.g. coal, oil and natural gas which increases carbon-dioxide concentration in the atmosphere and other greenhouse gases. These gases absorb a lot of heat from the sun during day and prevent heat loss at night (they act as a blanket). This accounts for the increase in the global temperatures by 2.5°C. this increase in temperature has led to the melting away of glaciers to the point of extinction of some glaciers e.g. the sempaya glaciers on mountain Rwenzori.
Aspect. This refers to the angle at which the slope receives the sun’s insolation. East Africa lies between the tropics and therefore experiences direct over sun throughout the year. This implies that all slopes of the mountain are subjected to at least 10 hours of great sunshine a day without any sheltered slope or obstructed slope to enable glacier formation.
All the precipitation received in east Africa is in form of rainfall but not snow. This also explains the little coverage. In the few areas where temperatures drop to below freezing point, rain water has to be first frozen to ice which is a long process.Impact of volcanism. Some of the high mountains where glaciation would have taken are volcanic in nature. The temperatures in these mountains are high due to the hot interior which brings about the warming effect on the surroundings. This is therefore preventing glacier formation
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