coral reefs in hot water study
Last Updated : GMT 06:49:16
Arab Today, arab today
Arab Today, arab today
Last Updated : GMT 06:49:16
Arab Today, arab today

Coral reefs in hot water: study

Arab Today, arab today

Arab Today, arab today Coral reefs in hot water: study

Last year, the 2015-16 El Nino helped kill off two-thirds
Paris - AFP

A spike in water temperature lasting only days bleached all the coral in a South China Sea atoll, and killed 40 percent of the tiny organisms within weeks, researchers reported Thursday.

The six degree Celsius (10.8 degrees Fahrenheit) surge at Dongsha Atoll in June 2015 was produced by a perfect storm of factors: the time of year, a record El Nino, and a rare lull in local winds and waves.

Open ocean water temperature in the region was 2 C (3.6 F) above normal. 

The dramatic die-off shows what can happen to shallow-water reefs when global warming is amplified by short-term weather, the scientists warned.

"The concern is that with a 2 C warming of the oceans, these weather anomalies will happen more often," said Anne Cohen, a researcher at the Woods Hole Oceanographic Institution in Massachusetts, and co-author of a study published in the journal Scientific Reports.

"It could be every couple of years, even every year -- and completely knock out the reefs," Cohen told AFP. 

Bleached coral is susceptible to disease, and needs time to recover -- one or more decades, depending on the species.

So far, Earth's surface atmosphere has warmed up by 1 C (1.8 F) compared late-19th century levels, with ocean temperatures climbing more slowly.

Already today, coral reefs around the world are declining or dying off at an alarming pace.

Last year, the 2015-16 El Nino helped kill off two-thirds of shallow-water corals in the northern part of Australia's 2,300-kilometre (1,400-mile) long Great Barrier Reef.

An unprecedented second year of bleaching is underway now.

- Like a hot tub -

El Ninos are natural climate cycles in the Pacific Ocean, every few years, that produce drier air and warmer ocean water at the surface in equatorial Asia.

After completing a routine survey of coral extent at the Dongsha Atoll in 2015, the scientists went to recover instruments from the water.

"That's when we saw that all the coral had turned white," said Cohen.

Under normal conditions, the reef is regularly flushed with cool water from the open ocean, she explained.

But with no wind or waves, "the water just sat there in the Sun -- it was like a hot tub."

Returning several weeks later, the scientists removed samples from the reefs to see whether the atoll's corals had endured, and survived, bleaching in the past.

The cores revealed three previous bouts going back to 1983 -- but none affecting more than 50 percent of the corals.

Coral reefs are incubators and habitat for thousands of marine species, and vital to the livelihoods of half-a-billion people around the world.

When ocean water warms, the tiny, reef-building creatures expel algae living in their tissue and turn white.

The 196-nation Paris climate pact calls for holding global warming to "well below" 2 C. 

On current trends, Earth's surface is on track to heat up by about 4 C (7.2 F).

 

arabstoday
arabstoday

Name *

E-mail *

Comment Title*

Comment *

: Characters Left

Mandatory *

Terms of use

Publishing Terms: Not to offend the author, or to persons or sanctities or attacking religions or divine self. And stay away from sectarian and racial incitement and insults.

I agree with the Terms of Use

Security Code*

coral reefs in hot water study coral reefs in hot water study

 



Name *

E-mail *

Comment Title*

Comment *

: Characters Left

Mandatory *

Terms of use

Publishing Terms: Not to offend the author, or to persons or sanctities or attacking religions or divine self. And stay away from sectarian and racial incitement and insults.

I agree with the Terms of Use

Security Code*

coral reefs in hot water study coral reefs in hot water study

 



GMT 12:11 2017 Thursday ,27 July

Tony Baroud to present new TV show

GMT 23:00 2017 Monday ,16 October

Egypt FM to head for Slovenia on Monday

GMT 20:06 2017 Friday ,20 January

Daesh in new demolitions at Syria’s Palmyra

GMT 21:06 2017 Friday ,24 November

Marriyum condemns Hayatabad terrorists attack

GMT 01:00 2017 Saturday ,25 November

Cabinet Affairs Minister Meets Indonesian Ambassador

GMT 02:34 2018 Thursday ,04 January

Merger creates state-owned gas giant

GMT 10:08 2017 Tuesday ,07 March

Geneva farce: The regime is the opposition

GMT 10:19 2017 Saturday ,18 November

AJK Prime Minister condemns across LoC shelling

GMT 11:34 2017 Wednesday ,22 March

33 Syrians killed in Air raid on Raqqa’s school

GMT 11:03 2017 Wednesday ,01 March

Asala declares her solidarity with George Wassouf

GMT 17:57 2017 Wednesday ,11 October

Mideast nations turn to private sector

GMT 14:11 2016 Wednesday ,30 November

Tunisia wins billion-dollar pledges to boost economy

GMT 23:41 2017 Tuesday ,26 September

Qatar laborer ‘sacked’ after speaking to UN team

GMT 04:28 2017 Tuesday ,21 March

Enrique Iglesias to headline Bahrain F1
Arab Today, arab today
 
 Arab Today Facebook,arab today facebook  Arab Today Twitter,arab today twitter Arab Today Rss,arab today rss  Arab Today Youtube,arab today youtube  Arab Today Youtube,arab today youtube

Maintained and developed by Arabs Today Group SAL.
All rights reserved to Arab Today Media Group 2021 ©

Maintained and developed by Arabs Today Group SAL.
All rights reserved to Arab Today Media Group 2021 ©

arabstoday arabstoday arabstoday arabstoday
arabstoday arabstoday arabstoday
arabstoday
بناية النخيل - رأس النبع _ خلف السفارة الفرنسية _بيروت - لبنان
arabstoday, Arabstoday, Arabstoday