2014 World Population Day: World Cities Will Be Home To Two-thirds of Global Population By 2050

A United Nations report released ahead of the 2014 world population day says two-thirds of the world's 7 billion people will live in urban areas by 2050, an increase of 2.5 billion, and at least 40 megacities will have a population of at least 10 million.

That proportion is expected to jump, so that more than six billion people will be city dwellers by 2045 while More than 10 million inhabitants will occupy Tokyo, Delhi, Shanghai, Mexico City and Sao Paulo by 2050.

Indeed, urbanization, combined with overall population growth, will boost the number of people in cities by 2.5 billion over the next three decades, with much of that growth in developing countries, especially in Africa.

India, China and Nigeria will make up 37 percent of the projected growth in the next three decades, with India adding 404 million city residents, China 292 million, and Nigeria 212 million, by 2050.

The key challenge for these countries will be meeting the needs of their growing urban population with basic services like education, health care, housing, infrastructure, transportation, energy and employment.

"Managing urban areas has become one of the most important development challenges of the 21st century," said John Wilmoth, Director of the Population Division in the UN's Department of Economic and Social Affairs.

According to the United Nations, the trend will pose infrastructure challenges for Africa and Asia, where 90 percent of the urban population growth is expected, the U.N' s World Urbanization Prospects report said, noting Africa and Asia will face numerous challenges in meeting the needs of their growing urban populations, including for housing, infrastructure, transportation, energy and employment, as well as for basic services such as education and healthcare.

The world's rural population, now 3.4 billion people, will decline as urbanization increases, the report says.