International
Hottest oceans in 400 years endanger Great Barrier Reef, scientists say
SYDNEY — Water temperatures in and around Australia's Great Barrier Reef have risen to their warmest in 400 years over the past decade, placing the world's largest reef under threat, according to research published on Aug 1. The reef, the world's la
The reef, the world's largest living ecosystem, stretches for some 2,400 km off the coast of the northern state of Queensland.
A group of scientists at universities across Australia drilled cores into the coral and, much like counting the rings on a tree, analysed the samples to measure summer ocean temperatures going back to the year 1618.
Combined with ship and satellite data going back around a hundred years, the results show ocean temperatures that were stable for hundreds of years begin to rise from 1900 onwards as a result of human influence, the research concluded.
From 1960 to 2024, the study's authors observed an average annual warming for January to March of 0.12 deg C per decade.
Since 2016, the reef has experienced five summers of mass coral bleaching, when large sections of the reef turn white due to heat stress, putting them at greater risk of death.
