The air in the vicinity of Earth’s biggest urban areas includes a wild variety of constituents emitted by cars, factories, trees, and much more. Tracking the fate of such air as it spreads outward is no simple task.

A new study looks at how the anticipated recovery of the ozone hole over Antarctica and simultaneous increase in greenhouse gas concentrations will combine to affect weather and climate in the Southern Hemisphere.

The return of sunlight in polar spring means ozone destruction above the Antarctic—and, in 2011, above the Arctic.

New research indicates that a regional nuclear war would deplete Earth’s protective ozone layer so profoundly that levels of ultraviolet radiation across the world would exceed levels now considered extreme.

New research points to more dust particles in the atmosphere than previously believed.