It is still possible to limit global warming to 1.5 degrees Celsius above pre-industrial levels, a study published Tuesday in Nature Communications found, as long as we act immediately to phase out fossil fuels.

The study used a climate model to determine what would happen if, beginning at the end of 2018, all existing fossil fuel infrastructure—from industrial equipment to cars to planes to ships to power plants—was replaced with renewable alternatives at the end of its design lifetime. The researchers found there would be a 64 percent chance of limiting warming to 1.5 degrees, in line with the most ambitious goal of the Paris agreement.