A, "Healthy" coral reef with living Acropora palmata and good water quality. B

A, "Healthy" coral reef with living Acropora palmata and good water quality. B, Degraded coral reef with dead A. palmata and poor water quality. Processes such as ocean acidification are rapidly transforming healthy reefs into degraded reefs in Puerto Rico and other Caribbean and western tropical Atlantic Ocean regions. Photographs by Ryan Moyer, USGS.