Ground-level ozone – which is produced by chemical reactions between air pollutants in the presence of sunlight – reduces crop growth and agricultural productivity. Two of the world’s most important staple crops, wheat and soybean, are particularly sensitive to the effects of ozone. Globally, ozone pollution has been estimated to cause more than $11 billion worth of crop damage every year.

3. 92 per cent of the global population live in places with unhealthy air quality.

Air pollution comes from many sources: Inefficient transport, coal-fired power plants, industrial activity, waste burning and other human activities are major sources, but natural events such as dust storms can also play a role.

4. Indoor air pollution kills 4.3 million people every year.

More than 40 per cent world’s population rely on open fires or traditional stoves to cook and heat their homes. The smoke that those fires produce includes heavy concentrations of carbon monoxide, particulate matter and other toxic air pollutants. Young children and women – who typically spend the most time inside around the fire – are at greatest risk of exposure.

5. More than 7,000 mayors have committed to reducing their cities’ air pollution emissions.

The Global Covenant of Mayors for Climate and Energy is an international alliance of cities and local governments that have committed to taking voluntary action to combat climate change by embracing low-emissions solutions. Mayors representing nearly 675 million people, or more than 9 per cent of the global population, have signed the Covenant.

By materials: https://web.unep.org/…/get-facts-6-things-you-need-know-abo…