https://www.sciencedaily.com/releases/2019/04/190411154731.htm

In 2015, Palmyra experienced its warmest water in recorded history, prompting a widespread bleaching event that affected over 90 percent of the corals surrounding the island. Researchers found that despite the widespread bleaching, most of the corals recovered, with less than 10 percent dying.

The conclusions are based on comprehensive monitoring of the reefs and is providing for more precise observations of how reefs are changing over time. The researchers used a long-term data set of thousands of pictures of the same reef area collected over eight years. These images were stitched together using custom software to create 3D photo mosaics of the ecosystem -- a virtual representation of the corals. The technology was developed by the 100 Island Challenge team, a collaborative group of marine ecologists and engineers using the latest technology to monitor coral reefs around the world.