Increasing Urban Populations May Lead to More Slums and Health Issues
The world's urban population is expected to grow by 2.6 billion people between 2011 and 2050, bringing the total number of urbanites to 6.3 billion, according to new research conducted by the Worldwatch Institute for its Vital Signs Online service. This urban expansion will be especially burdensome for developing countries, where 82 percent of the world's population currently lives, writes report author Grant Potter.
Although the developing world is less urbanized than the industrial world in relative terms, developing countries are home to an estimated 1.54 billion more people. In absolute terms, the developing world is projected to add approximately 2.45 billion people to its cities by 2050, while the industrial world is due to add just 170 million.
Within the developing world, the vast majority of this urban growth is projected to occur in Asia and Africa. Asia far outstrips Africa in total population, with 4.2 billion people in 2011 compared with Africa's 1 billion. But these regions are also the least urbanized areas on Earth: Asia's population was 45 percent urban in 2011, and Africa's was only 40 percent urban. In Latin America and the Caribbean, by contrast, 78 percent of the regions' 599 million people live in cities.
A characteristic feature of Asian urbanization is the prevalence of "megacities" that are home to more than 10 million people. In 2011, there were 23 such cities worldwide, 13 of which were Asian. By 2025, the total number of megacities is expected to reach 37—with 21 in Asia alone. Specifically, Southeast Asia is home to the most densely populated cities: approximately 16,500 people per square kilometer are squeezed into the region's urban areas.
Cities, especially in the developing world, must find a way to provide essential services to their ever-increasing populations. When cities fail to meet these essential needs on a large scale, they create areas known as slums, where households typically lack safe drinking water, safe sanitation, a durable living space, or security of a lease. According to UN HABITAT, 828 million people in developing-world cities are considered slum dwellers—one in every three residents. Slum populations are expected to grow significantly in the future, and UN HABITAT projects that 6 million more people live in slums every year.
The World Health Organization identifies the rapid increase of urban populations, especially slum populations, as the most important issue affecting health in the 21st century.
Continue reading at Worldwatch Institute.
City image via Shutterstock.