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Half of all reefs off the coast of Taiwan have been bleached due to warming seas, with a third damaged so profoundly they cannot be saved, according to a new report.

The report, published on Jan. 13 by the Taiwan Coral Bleaching Observation Network (TCBON), analyzed 62 locations around the island nation in 2020 and revealed bleaching was at its highest level ever recorded.

Kuo Chao-yang, a postdoctoral scholar at research institute Academia Sinica, said that even significant future declines in water temperatures — which are currently at their warmest level in decades — wouldn't be enough for some of the reefs ever to recover. 

"It's like the corals are being cooked," Chao-yang said, according to Channel News Asia. "Coral reefs are the rainforest in the ocean. A coral reef without corals is just like a forest without trees, and the reef-associated creatures will have to leave because there is no shelter or food.”

Chao-yang added: "If corals are dead, the coral reef ecosystem will start to collapse as its root is cut."

Ideal ocean water temperatures for healthy reefs is somewhere between 18 degrees Celsius and 29 degrees Celsius. 

Temperatures in the country’s northern waters reached 31 degrees Celsius last year.

A surprising consequence of climate change has been blamed for Taiwan's warming seas. 

The country, renowned for its devastating typhoons, recorded not a single typhoon in 2020 for the first time in half a century. Over the past 10 years, the number of typhoons making landfall dropped to an average of 2.5 per year, down from the longstanding average of three or four, according to Reuters.

Typhoons often cause a phenomenon known as vertical mixing — where strong winds stir up cold water from the deep ocean, which then mixes with warmer surface waters, in turn causing the sea's upper layer to cool substantially. 

separate report published in the Advances in Atmospheric Sciences publication reveals the world’s upper ocean temperatures hit a record high in 2020, absorbing 20 sextillion joules of heat due to climate change.

The heat is the equivalent to the energy from 10 Hiroshima atomic bombs being released every second of the year, according to the New Daily.

“Over 90% of [the world’s] excess heat is absorbed by the oceans, leading to an increase of ocean heat content and sea-level rise, mainly through thermal expansion and melting of ice over land,” lead author Lijing Cheng wrote in the report. “These processes provide a useful means to quantify climate change.”


Defend the Planet

Half of Taiwan’s Reefs Have Been Bleached and a Third Are Dying: Report

By Madeleine Keck