An Orkney man in Tobago

Something terrible happened last summer beneath the startlingly blue Caribbean seas off the island of Tobago, where we have just been staying. The Buccoo coral reef, home to one of the richest marine ecologies in the world, turned a brilliant white. “It looked as if it had been bleached,” said my brother-in-law, a marine biologist. “It was a strangely beautiful sight, but in fact it was sick, so sick that we wondered whether it could recover.”

Magnus Linklater: A stark message in deadly white coral, 19 April