UN: Half of world's population growth is likely to occur in Africa

Story highlights

  • A new report predicts the world's population will hit a staggering 9.8 billion by 2050
  • Fertility rates are dropping globally but remain high in Africa
  • Nine countries will contribute to more than half of the world's population growth, and five are on the African continent

(CNN)Nigeria will overtake the United States to become the third-most populous country in the world by 2050, according to a United Nations report.

Currently the seventh-most populous country in the world, the West African nation is projected to surpass the 300 million people mark by 2050, according to The World Population Prospects 2017.
    The report predicted that the world population will hit a staggering 9.8 billion by 2050, and forecasted that over half of the expected growth between 2017 and 2050 is likely to occur in Africa.
    Here are five African countries that will contribute the most to the world's population growth.

    Nigeria

    A view of multi-story buildings in Lagos, Nigeria's commercial capital.
    With an estimated population of more than 180 million people, Nigeria experienced annual population growth of about 2.7% between 2010 and 2015, according to the UN.
    Nigeria's population in numbers

    Current population: 187 million (2016)

    Population by 2050: over 300 million

    Largest city: Lagos- between 17.5 and 21 million residents

    High fertility rates, high infant mortality rates and the cultural value of large families have all been cited as factors driving Nigeria's population boom.
    Home to four of the world's fastest-growing cities, it has been described as an economic powerhouse. However, there are fears that such an increase in population could cripple Nigeria's already inadequate infrastructure.

    The Democratic Republic of Congo

     A view of Kinshasa city
    The Democratic Republic of Congo population in numbers

    Current population: 79.8 million

    Population by 2050: 214 million

    Largest city: Kinshasha 7.8 million residents

    The Democratic Republic of Congo is the largest country in Francophone Africa, with annual population growth of 3.2%. As in Nigeria, Tanzania, Uganda and Afghanistan, high fertility levels have contributed to the country's population increase. The fertility rate in 2016 was 4.53 births per woman.
    The country's capital, Kinshasa, has the third-largest urban agglomeration on the continent and is predicted to add more than six million people to its population by 2025, cementing its status as an African mega-city.

    Ethiopia

    Aerial view of the city of Addis Ababa at night.
    Ethiopia population in numbers

    Current population: 101.7 million (2016)

    By 2050: 168.6 million

    Largest city: Addis Abbaba-3.6 million residents (city) 4.6 million residents (metro)

    As well as a population boom, the country has experienced an economic boost and is on target to become a middle-income country by 2025.
    Addis Ababa, the country's capital and largest city, has an important role to play, but the city's rapid development has led to tensions and accusations of marginalization.

    Tanzania

    Dar es Salaam Waterfront
    From 2010 to 2015, Tanzania experienced an annual population growth rate of 3.2%, and its population is predicted to exceed 130 million by 2050.
    Tanzania population in numbers

    Current population: 54.2 million (2016)

    By 2050: 134.8 million

    Largest city: Dar-es Salaam- 4.1 million residents

    Early motherhood, high fertility rates and falling mortality rates are some of the reasons given for Tanzania's population explosion.
    According to the African Development Bank, Dar es Salaam, the country's capital, is expected to grow by 85% from now until 2025. The city is expected to become a mega-city by the 2030s.

    Uganda

    Uganda has one of the fastest growing populations in the world. Between 2010 and 2015, it experienced an annual population growth rate of 3.3%.
    Uganda population in numbers

    Current population: 36.6 million

    By 2050: 101.5 million

    Largest city: Kampala- 1.3 million residents

    As in many African countries, high fertility rates are a major contributing factor to Uganda's population figures. It has the fifth-highest fertility rate in the world, with women having an average of 5.8 children in 2016.
    The World Bank estimates Kampala, the country's capital, will experience rapid urbanization and the population will increase from six million in 2013 to more than 20 million by 2040.