Story of the Week - How global warming is permanently reshaping the Great Barrier Reef

Story of the Week - Most thriving cities boast complex architecture — tall towers looming over narrow alleyways and plenty of nooks and crannies packed with life.  Coral reefs are the cities of the undersea world, gradually constructed by the soft-bodied animals that build hard skeletons around themselves.

According to a new study in Nature, the Great Barrier Reef [Google Earth] — the world’s largest coral system — experienced two widespread coral bleaching events in 2016 and 2017 that did more than just damage thousands of miles of corals.

The bleaching and subsequent coral death, caused by unusually warm water, also impaired the reef’s ability to replenish and repair its architecture.  The study found that afterward, the number of newly born corals landing on the reefs dropped 89 percent below average historical levels.

Moreover, these recent replacement baby corals weren’t the table-shaped or big branching species that provide the most “city” architecture.  Even if the reef is someday covered in coral once again, the structure itself won’t be the same, with consequences for the reef’s biodiversity.

The Great Barrier Reef has rebounded from cyclones and smaller bleaching incidents before, the researchers said.  It’s made up of some 3,000 interconnected reefs, so in the past if one reef got damaged, others nearby could resupply the area with new corals.  But the modern bleaching events — with their massive scale and increasing frequency — could put an end to that recovery cycle.

Read more at How global warming is permanently reshaping the Great Barrier Reef 
(Credit: Viky Stein, PBS News Hour, Apr 3, 2019)