'Ocean darkening' a cause for concern – scientists

More than a fifth of the global ocean has become darker over the past two decades, according to University of Plymouth research.

The process, known as "ocean darkening", occurs when changes to the ocean's upper most level reduce the depth at which sunlight can travel.

The study, published in Global Change Biology, found 21% of the global ocean had become darker between 2003 and 2022.

Reasons for ocean darkening were believed to be down to factors such as changes in algal bloom dynamics, shifts in sea surface temperatures and artificial light, researchers said.