Coral reefs at risk of dissolving as oceans get more acidic, finds new study
Coral reefs could start to dissolve before 2100 as man-made climate change drives acidification of the oceans, scientists said. Acidification will threaten sediments that are building blocks for reefs. Corals already face risks from ocean temperatures, pollution and overfishing. “Coral reefs will transition to net dissolving before end of century,” the Australian-led team of scientists wrote in the U.S. journal Science. “Net dissolving” means reefs would lose more material than they gain from the growth of corals.
Carbon dioxide, the main man-made greenhouse gas, forms a weak acid in water and threatens to dissolve the reef sediments, made from broken down bits of corals and other carbonate organisms that accumulate over thousands of years, it said. The sediments are 10 times more vulnerable to acidification than the tiny coral animals that also extract chemicals directly from the sea water to build stony skeletons that form reefs, the study said.
Coral animals will be able to keep growing and replenish reefs long after sandy sediments start to dissolve, lead author Bradley Eyre, of Southern Cross University, told Reuters. “This probably reflects the corals’ ability to modify their environment and partially adapt to ocean acidification whereas the dissolution of sands is a geo-chemical process …read more
