The sea is becoming greener due to changes in plankton populations, analysis of Nasa images finds.
When comparing these changes in colour with those hypothesised from a computer model simulating what the oceans would look like if human-caused global heating had never taken place, the change was clear.
“We do have changes in the colour that are significantly emerging in almost all of the ocean of the tropics or subtropics,” said Cael.
The changes have been detected over 56% of the world’s oceans – an area greater than all of the land on Earth.
“The reason we care about this is not because we care about the colour, but because the colour is a reflection of the changes in the state of the ecosystem,” said BB Cael, a scientist at the National Oceanography Centre at the University of Southampton and author of the study published in Nature.