Climate Change impacts on Eastern Africa

In the 20th century, Africa warmed by an average of 0.7°C, while overall rainfall in eastern Africa increased.
For the 21st century, climate projections are that temperatures will increase between 2 and 5°C.

Freshwater

In the wet months from December to February, rainfall might increase by up to 20%. But droughts will also become much more severe, with reduction in rainfall of up to 10% in the driest season from June to August.
The water levels in rivers may also fall significantly; this has been established for the River Pangani and by 10% in the River Ruvu in Tanzania.
This is also due to the fact that the remaining African glaciers are all set to disappear; the glaciers on Mount Kilimanjaro are likely to disappear by around 2020.
Changing water levels in lakes such as Lake Tumba in DR Congo and in Lake Victoria have been attributed to climate change. These changes may become more variable and serious as weather extremes become more frequent and intense.

Food Security

Long-cycle crops will suffer from climate-induced, prolonged droughts, e.g. in the growing season of March to May.
Some seasons will see abnormally high amounts of rainfall which may lead to floods with disruptions to farming, transport, and direct threats to people's safety.
Warming will likely disturb local freshwater fisheries.

Human Health

Climate change is expected to increase the spread and intensity of future disease outbreaks.
Climate change resulting in warm and rainy days can lead to incidences of malaria outbreaks (Craig et al., 2004).
Temperature affects the development rates of vectors and parasites while rainfall affects the availability of mosquito breeding sites (Zhou et al., 2004; Craig et al., 2004).

Extreme Weather

Warmer temperatures mean more weather extremes which will cause more storms and floods. But they also mean longer and more severe droughts because rainfall could be reduced in already dry months.
A temperature increase of 1.2°C and the resulting changes in precipitation, soil moisture and water irrigation would cause large areas of land that now support tea cultivation in Kenya to be largely unusable (Simms, 2005).

Sea Level Rise

Sea level rise happens because the warming sea water expands, and because glaciers are melting.
In East Africa, 2 of the world’s most diverse types of habitats are specifically at risk from sea level rise: coral reefs and mangroves. Both are crucial in protecting the coast from storms. Once the reefs and mangroves are gone, the coast will be bare and people will find it much harder to resist to storms and erosion.

Biodiversity

Many forests are very sensitive to even small changes in precipitation, especially during the growing season.
Climate change has the potential to alter migratory routes (and timings) of species that use both seasonal wetlands (e.g., migratory birds) and track seasonal changes in vegetation (e.g., herbivores). This may increase conflicts between people and large mammals such as elephants, particularly in areas where rainfall is low.
Climate change to ecosystems could have a cascading effect on species and diversity of East Africa.
The ranges of different species within a habitat may not shift at the same speed due to climate change, which means that habitats may disintegrate piece by piece.
Altering the distribution of dry and humid seasons will also affect the breeding rates and breeding success of many animals, and hence genetic composition of these populations.
In sub-Saharan Africa, which includes parts of East Africa, several ecosystems, particularly grass and shrub savannas, are shown to be highly sensitive to short-term availability of water due to climate variability.