oceans in distress foreshadow mass extinction
Last Updated : GMT 06:49:16
Arab Today, arab today
Arab Today, arab today
Last Updated : GMT 06:49:16
Arab Today, arab today

Less resilient to climate change

Oceans in distress foreshadow mass extinction

Arab Today, arab today

Arab Today, arab today Oceans in distress foreshadow mass extinction

Experts said that dying coral reefs are accelerating
Paris - AFP

Experts said that dying coral reefs are accelerating Pollution and global warming are pushing the world's oceans to the brink of a mass extinction of marine life unseen for tens of millions of years, a consortium of scientists warned Monday. Dying coral reefs, biodiversity ravaged by invasive species, expanding open-water "dead zones," toxic algae blooms, the massive depletion of big fish stocks -- all are accelerating, they said in a report compiled during an April meeting in Oxford of 27 of the world's top ocean experts.
Sponsored by the International Programme on the State of the Ocean (IPSO), the review of recent science found that ocean health has declined further and faster than dire forecasts only a few years ago.
These symptoms, moreover, could be the harbinger of wider disruptions in the interlocking web of biological and chemical interactions that scientists now call the Earth system.
All five mass extinctions of life on the planet, reaching back more than 500 million years, were preceded by many of the same conditions now afflicted the ocean environment, they said.
"The results are shocking," said Alex Rogers, an Oxford professor who heads IPSO and co-authored the report. "We are looking at consequences for humankind that will impact in our lifetime."
Three main drivers are sickening the global marine environment, and all are a direct consequence of humans activity: global warming, acidification and a dwindling level oxygen, a condition known as hypoxia.
Up to now, these and other impacts have been studied mainly in isolation. Only recently have scientists began to understand how these forces interact.
"We have underestimated the overall risks, and that the whole of marine degradation is greater than the sum of its parts," Rogers said. "That degradation is now happening at a faster rate than predicted."
Indeed, the pace of change is tracking or has surpassed the worst-case scenarios laid out by the UN Intergovernmental Panel on Climate Change (IPCC) in its landmark 2007 report, according to the new assessment.
The chain reaction leading to increased acidification of the oceans begins with a massive influx of carbon into Earth's climate system.
Oceans act as a massive sponge, soaking up more than a quarter of the CO2 humans pump into the atmosphere.
But when the sponge becomes too saturated, it can disrupt the delicately balanced ecosystems on which marine life -- and ultimately all life on Earth -- depends.
"The rate at which carbon is being absorbed is already far greater now than during the last globally significant extinction of marine species 55 million years ago," when some 50 percent of deep-sea life was wiped out, the report said.
That event, called the Paleocene-Eocene Thermal Maximum, or PETM, may be an ancient dress rehearsal for future climate change that could be even more abrupt and more damaging, some scientists fear.
Pollution has also taken a heavy toll, rendering the oceans less resilient to climate change.
Runoff from nitrogen-rich fertiliser, killer microbes, and hormone-disrupting chemicals, for example, have all contributed to the mass die-off of corals, crucial not just for marine ecosystems but a lifeline for hundreds of millions of people too.
The harvesting up to 90 percent of some species of big fish and sharks, meanwhile, has hugely disrupted food chains throughout the ocean, leading to explosive and imbalanced growth of algae, jellyfish and other "opportunistic" flora and fauna.
"We now face losing marine species and entire marine ecosystems, such as coral reefs, within a single generation," said Daniel Laffoley, head of the International Union for Conservation of Nature's (IUCN) World Commission on Protected Areas, and co-author of the report.
"And we are also probably the last generation that has enough time to deal with the problems," he told AFP by phone.

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*

oceans in distress foreshadow mass extinction oceans in distress foreshadow mass extinction

 



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*

oceans in distress foreshadow mass extinction oceans in distress foreshadow mass extinction

 



GMT 11:25 2017 Wednesday ,13 December

Nobel prize winner's book turned down

GMT 05:47 2017 Thursday ,26 January

Dow hits 20,000 as Trump trade reignites

GMT 13:13 2017 Thursday ,02 November

Myanmar's Suu Kyi makes first visit

GMT 21:48 2012 Monday ,09 July

Clinton makes unannounced stop in Afghanistan

GMT 00:10 2017 Wednesday ,13 December

Children dead after Sanaa air strike

GMT 21:48 2017 Friday ,11 August

GCC condemns attacks on Saudi missions in Iran

GMT 01:24 2017 Friday ,08 December

US decision suspended for six months

GMT 08:41 2017 Saturday ,18 March

Sit-In to Protest Street Music Ban in Casablanca
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