Coral reefs 'will be overwhelmed by rising oceans'

[Judi Lynn]

Study finds fragile marine ecosystems cannot grow fast enough to keep pace with sea levels

Robin McKie
Sat 23 Jun 2018 17.21 EDT

Scientists have uncovered a new threat to the world’s endangered coral reefs. They have found that most are incapable of growing quickly enough to compensate for rising sea levels triggered by global warming.

The study suggests that reefs – which are already suffering serious degradation because the world’s seas are warming and becoming more acidic – could also become overwhelmed by rising oceans.

The research – led by scientists at Exeter University and published in Nature this week – involved studying growth rates for more than 200 tropical western Atlantic and Indian Ocean reefs. It was found only 9% of these reefs had the ability to keep up with even the most optimistic rates of sea-level rises forecast by the Intergovernmental Panel on Climate Change. “For many reefs across the Caribbean and Indian Ocean regions, where the study focused, rates of growth are slowing due to coral reef degradation,” said Professor Chris Perry, of Exeter University. “Meanwhile, rates of sea-level rise are increasing – and our results suggest reefs will be unable to keep up. As a result, water depths above most reefs will increase rapidly through this century.”

Sea levels rose by several inches over the past century and measurements indicate the speed of this increase is now rising significantly. Two key factors are involved: climate change is making ocean water warmer and so it expands. And as ice sheets and glaciers melt, they increase amounts of water in the oceans.

More:
https://www.theguardian.com/environment/2018/jun/23/coral-reefs-overwhelmed-by-rising-oceans