Like many highly dense megacities, the view of Cairo from the air is one of concrete buildings and tangled overpasses stretching as far as the eye can see.
Green areas comprise less than four percent of the total urban built area, and recent construction projects have resulted in the destruction of tens of acres of the city’s already-sparse green space.
In places like Cairo and Dhaka, Bangladesh, the lack of green space contributes to a host of problems: increased air pollution, higher air temperatures, and greater exposure to ultraviolet radiation, all of which are making these cities increasingly dangerous places to live. According to the World Health Organization, outdoor air pollution kills 4.2 million people every year, mostly in low- and middle-income countries.
Outdoor air pollution is particularly deadly in dense urban environments in these nations.
In Cairo, for example, researchers estimate that 19 percent of non-accidental deaths in people over the age of 30 can be attributed to long-term exposure to two common air pollutants — nitrogen dioxide and fine particulate matter (PM2.5). That’s an estimated 20,000 deaths each year there alone.
Recent development has ignored the threat of a warming climate, which is causing temperatures to rise, drought conditions to worsen, and extreme weather events like flash flooding and sandstorms to become more common.
Why do cities like these lack green space?
The natural environment often plays a role. Cairo, for example, is in a desert; it’s not naturally lush. Rapid urbanization in recent decades has also led to the development of informal neighborhoods and other new construction projects, exacerbating the problem. But mostly, it comes down to planning.