Climate change threatens ‘to wipe out reefs in global coral bleaching event’

Thousands of square miles of coral reef will be wiped out in a catastrophe brought on by warming temperatures in the ocean, scientists warn. The global coral bleaching event - only the third such incident in recorded history - could affect more than a third of the world’s reefs, the researchers said. The disaster, which could destroy 12,000 sq km (4,600 sq miles) of reef, is being brought on by rising ocean temperatures caused by climate change. The effects are worsened by a natural phenomenon known as El Nino which raises global temperatures and a Pacific warm water mass known as “the blob”.

With hundreds of millions of people relying on fisheries and reefs for sustenance, the repercussions of a global coral bleaching event could be potentially disastrous.

Prof Ove Hoegh-Guldberg, bleaching researcher

Global coral bleaching events, last seen in 2010, are declared when the three major ocean basins, the Indian, Pacific and Atlantic, all see widespread episodes across multiple large reefs. During these events corals expel the golden-brown algae which grow within their body tissue, exposing their white skeletons. If it is prolonged they die on masse. The current El Nino, which is contributing to the problem, is expected to be the strongest since 1998 when the first global coral bleaching event was recorded. Dr Mark Ekin, from the US government’s National Oceanic and Atmospheric Administration, said: “This is only the third time we’ve seen a global coral bleaching event. What really has us concerned is this event has been going on for over a year and is likely to last another year.”

We may be looking at losing somewhere in the range of 10 to 20% of the coral reefs this year

Coral reef expert Mark Eakin

Science coral bleaching