Page 7 - Buildings That Breathe: Greening the World’s Cities

Many big cities are crowded and polluted . Green buildings and other green
spaces can improve life for city residents .

Besides releasing carbon dioxide, the cars, factories, homes, and
businesses in big cities do additional damage. They create other types
of pollution, such as nitrogen dioxide, sulfur dioxides, and particulate
matter, or small airborne particles, such as soot from smokestacks.
According to the World Health Organization (WHO), an international
agency devoted to improving human health, 91 percent of the world’s
population breathes unhealthy air. About nine million people die every
year from air-pollution–related illnesses, such as strokes, heart disease,
and lung disease.
The entire Earth is warming, but even without climate change,
cities are warmer than nonurban areas, such as farms and forests.
Rural areas have an abundance of natural features that cool the air,
including green plants, shade-giving trees, and wetlands. With their
paved roads and big buildings, cities have far fewer green spaces and

Greening Our Cities 7