Scientists in Florida have found that underwater “umbrellas” can protect coral reefs from heat damage — and even partly reverse bleaching.

Researchers from Nova Southeastern University placed 20 custom-made shades over colonies of two brain coral species at Newfound Harbor in the Florida Keys in summer 2024.

The parasol-like shades, made of PVC pipe and nylon fabric, floated 30cm above each coral and cut incoming light by 60 per cent. Twenty matching corals served as controls.

Despite the second-hottest summer on record in those waters, the shaded corals lost less colour than expected — and some even recovered colour.

Shading cannot cool the water, explained lead author Dr Karen Neely. But it blocks ultraviolet and irradiance damage, which makes heat damage worse.

The study, published in Frontiers in Marine Science, followed the devastating 2023 bleaching event that wiped out branching corals in Florida.

Scientists say shading offers a small-scale tool to save targeted corals, though tackling climate change remains essential.