Another mass bleaching event is devastating the Great Barrier Reef. What will it take for coral to survive?

Bleached coral beside the darker, healthier coral. Photo taken in February Nathan Cook, Author provided

It’s official: the Great Barrier Reef is suffering its fourth mass bleaching event since 2016. We dived into the reef yesterday and saw the unfolding crisis firsthand.

Descending beneath the surface at John Brewer Reef near Townsville, our eyes were immediately drawn to the iridescent whites, blues and pinks of stressed corals among the deeper browns, reds and greens of healthier colonies.