Â鶹´«Ã½

Skip to main content

Climate change is killing the world's coral reefs as oceans warm, study says

Share
MEXICO CITY -

The world's coral reefs are under attack by climate change and more will disappear if oceans keep warming, according to a report released Tuesday.

The study by the (GCRMN), a UN-supported global data network, showed that 14 per cent of the world's coral on reefs was already lost between 2009 and 2018, equal to about 11,700 square kilometres, an area 2.5 times the size of Grand Canyon National Park.

Corals face an "existential crisis," scientists said, as sea surface temperatures rise. The report spanned data for 40 years, 73 countries and 12,000 sites.

Sharp spikes in warming are particularly damaging, a phenomenon scientists say is linked to human-caused climate change.

The study looked at 10 coral reef-bearing regions around the world and found that loss was mainly attributed to coral bleaching, which happens when corals, under stress from warmer water, expel the colorful algae living in their tissues, making them turn white.

One severe bleaching event in 1998 alone killed 8 per cent of the world's corals, the study said.

The hardest hit areas are South Asia, Australia, the Pacific, East Asia, the Western Indian Ocean, the Gulf and Gulf of Oman.

Overfishing, unsustainable coastal development and declining water quality are other factors battering the reefs.

"There are clearly unsettling trends toward coral loss, and we can expect these to continue as warming persists," said Paul Hardisty, chief executive of the Australian Institute of Marine Science, in a statement shared by the United Nations.

The global ocean has warmed faster over the past century than since the end of the last deglacial transition, around 11,000 years ago, the Intergovernmental Panel on Climate Change (IPCC) said .

While coral reefs cover less than 1 per cent of the ocean floor, they support more than 25 per cent of marine biodiversity, including turtles, fish and lobsters, which fuel global fishing industries.

The reefs are responsible for an estimated US$2.7 trillion annually in goods and services, including tourism, the report said.

Scientists did find, however, there was about a 2 per cent regain among coral reefs 2019, showing they can be resilient when given respite from the siege of factors working against them.

If pressure is relieved on the coral reefs, they could flourish again within a decade to pre-1998 levels, the report said.

Recent efforts to support coral reefs include a mitigation project off the coast of Caribbean nation Antigua and Barbuda called Ocean-Shot, which uses technology that mimics the design and shape of natural reefs to provide opportunities for colonization by corals and other marine life.

CTVNews.ca Top Stories

An Edmonton man says he was in the wrong place at the wrong time when he was injured by members of the Edmonton Police Service last year.

BREAKING

BREAKING

The brother of a 27-year-old man who was fatally shot in Scarborough over the weekend has been arrested and charged in connection with his death, say police.

Local Spotlight

Cole Haas is more than just an avid fan of the F.W. Johnson Wildcats football team. He's a fixture on the sidelines, a source of encouragement, and a beloved member of the team.

Getting a photograph of a rainbow? Common. Getting a photo of a lightning strike? Rare. Getting a photo of both at the same time? Extremely rare, but it happened to a Manitoba photographer this week.

An anonymous business owner paid off the mortgage for a New Brunswick not-for-profit.

They say a dog is a man’s best friend. In the case of Darren Cropper, from Bonfield, Ont., his three-year-old Siberian husky and golden retriever mix named Bear literally saved his life.

A growing group of brides and wedding photographers from across the province say they have been taken for tens of thousands of dollars by a Barrie, Ont. wedding photographer.

Paleontologists from the Royal B.C. Museum have uncovered "a trove of extraordinary fossils" high in the mountains of northern B.C., the museum announced Thursday.

The search for a missing ancient 28-year-old chocolate donkey ended with a tragic discovery Wednesday.

The Royal Canadian Mounted Police is celebrating an important milestone in the organization's history: 50 years since the first women joined the force.

It's been a whirlwind of joyful events for a northern Ontario couple who just welcomed a baby into their family and won the $70 million Lotto Max jackpot last month.