A corrosive concoction: The combined effects of ocean warming and acidification on the early growth of a stony coral are multiplicative

► We test settlement and growth of Porites panamensis in warmer and more acidic seawater. ► Separately, neither warmth nor acidity hindered coral settlement. ► When combined, warmth and acidity reduced growth by a third. ► Coral growth will be severely impeded under warmer more acidic conditions.