Other writing

Madrid was hailed as a public health beacon when it rolled out ambitious restrictions on the most polluting cars. Seven months and one election day later, a new conservative city council suspended enforcement of the clean air zone.

A wood stove emits more harmful air particulates than a diesel truck. Does their newfound popularity in cities threaten to wipe out progress in reducing air pollution?

ULAANBAATAR, MONGOLIA — Coal is everywhere in Mongolia’s frigid capital. It sits beneath the towering smokestacks of power plants in piles as big as football fields. Drivers haul it through town in the open beds of pickup trucks.

BEIJING, CHINA — Dirty air is part of life in China, unavoidable and in your face. It has inspired a tremendous boom in renewable energy, as the Chinese government begins to try to wean the country off coal. It has also inspired a level of citizen action that is unusual in an autocratic country.

Nicole Grobert is German, but she has spent almost all of her career in Britain, developing tiny nanomaterials and figuring out how to use them in everything from artificial bones to super-efficient batteries.

HAINING, CHINA — The squares of silicon are hardly thicker than sheets of paper, each about six inches by six, with narrow stripes of silver. They come into the factory by the thousands, stacked in cardboard boxes, and within hours, they’ll be ready to leave again.