JAKARTA’s air, which is becoming hotter and filthier, is making the people who live there more prone to a range of illnesses, especially respiratory tract problems caused by breathing air containing sulfur dioxide (SO2), as in the case of President Joko Widodo, who has had a cough for four weeks.

Sulfur dioxide is a pollutant produced from burning coal that can damage respiratory tracts. Jakarta is surrounded by 16 coal-fired steam power p