Thin sunscreen layer to save reef from bleaching for first time in twenty million years

Scientists are suggesting that a thin layer of floating calcium carbonate can cut sunlight over reefs by 30% and save some high value reefs from bleaching.

This should work well on reefs that evolved in the last fifty years and which don’t have moving water.

But half of the coral genera around today have been around since the Oligocene (23-34 million years) and for most of that time the oceans were warmer. (Lucky human civilization evolved just in time to save all these reefs from extinction.)

Bleaching has probably been going on for millions of years longer than we have been scuba diving with cameras to film it. Not surprisingly, marine life has ways to adapt to heatwaves by chucking out the symbionts that don’t thrive in higher temperatures and replacing them up new inhabitants that do.

Yes, let’s cover our most diverse and important reef systems with an artificial layer that cuts incoming sunlight by a third — What could possibly go wrong?

Ultra-fine film possible saviour for Great Barrier Reef

Scientists from the Australian Institute of Marine Biology say tests of a floating “sun shield” made of calcium carbonate show it could protect the reef from the effects […]