Cities and cases

The city of Addis Ababa is the capital of Ethiopia. The population of Addis has been very dynamic. What used to be 443,000 in 1961 has grown 2,7 in 2007 in official figures, however, estimates are that the population has reached 4 million. Addis Ababa has a complex mix of subtropical highland climate. Mid-November to January is characterized by dry winters. The short rainy season is from February to May, with warm temperatures and a pleasant rainfall. The long wet season is from June to mid-September; it is the major winter season of the country.  The city is located at 2,200 meters above sea level, at the foot of a mountain range. Many polluted rivers pass by the city. The city experiences both heavy rains and severe drought. Several of the rivers are equipped with dams for the water supply of the city.

The City of Dar es Salaam is Tanzania's largest and richest city, serving as a regionally important economic center. The Dar es Salaam Region had a population of 4,364,541 as of the official 2012 census. Dar es Salaam has a tropical wet and dry climate, with two different rainy seasons. Annual rainfall is approximately 1,100 mm (43 in), and in a normal year there are two distinct rainy seasons: "the long rains", which fall during April and May, and "the short rains", which fall during October and November. Dar es Salaam is located in a river delta. In the rainy season, many areas of the city suffer from flooding and stagnant water. According to researchers, 50% of the problems with flooding, however, a consequence of human impact and 'bad management' such as garbage in drainage channels and streams, lack of infrastructure and so on.