The thing that struck Maya Gabeira was the sound. “I had never heard anything similar: it was the first affirmation that that was the biggest wave I had ever ridden,” she says. “It was just ‘phwoooaaaarrrrrrr.’” She mimics a bomb exploding in her hands. There was also a continuous “Brrrrrrrrrrrrr,” she says, like a deep engine humming – the sound of tonnes of water falling, falling, falling from a great height. “It almost vibrates inside your...