Over two-thirds of Japan’s biggest coral reef has died, according to a survey released Tuesday by the Japanese environment ministry.
The survey was conducted at 35 points along the Sekiseishoko coral reef, an area set between the remote Ishigaki and Iriomote islands, about 1,200 miles (1,900km) southwest of Tokyo.
A Japan Times report on the survey quoted a ministry official as saying that a phenomenon called bleaching was responsible for the drastic reduction in coral, likely as a result of warming sea temperatures due to climate change.
Bleaching occurs when unusually warm water causes coral to expel the algae living in their tissues, causing the coral to turn completely white. Unless water temperatures quickly return to normal, the coral eventually dies from lack of nutrition.
2016 saw a worsening of bleaching on the reef due to ocean temperatures occurring that were one to 2ºC higher than normal between the months of June and September. Some even reached the unusually high temperature of 30ºC, the local daily reported.
According to the survey, more than 91 percent of the reef’s coral is at least partly bleached.
This comes after scientists confirmed the largest die-off of corals ever recorded on Australia’s Great Barrier Reef last year with the worst affected area, a 700km swath of reefs in the northern region of the Great Barrier Reef, losing an average of 67 percent of its shallow-water corals over an eight month period.
As global temperatures continue to rise as a result of manmade climate change, The Reef Studies Centre warns that similar events will be the new normal, occurring every two years by the mid-2030s.