'Evil twin' threatens world oceans, scientists warn

(PhysOrg.com) -- The rise in human emissions of carbon dioxide is driving fundamental and dangerous changes in the chemistry and ecosystems of the world’s oceans, international marine scientists warned today.

“Ocean conditions are already more extreme than those experienced by and ecosystems for millions of years,” the researchers say in the latest issue of the journal Trends in Ecology and Evolution (TREE).

“This emphasises the urgent need to adopt policies that drastically reduce CO2 emissions.”

, which the researchers call the ‘evil twin of global warming', is caused when the CO2 emitted by human activity, mainly burning , dissolves into the oceans. It is happening independently of, but in combination with, global warming.

“Evidence gathered by scientists around the world over the last few years suggests that ocean acidification could represent an equal - or perhaps even greater threat - to the biology of our planet than ,” co-author Professor Ove Hoegh-Guldberg of the ARC Centre of Excellence for Coral Reef Studies and the Global Change Institute at The University of Queensland said.

More than 30 percent of the CO2 released from burning fossil fuels, cement production, deforestation and other human activities goes straight into the oceans, turning them gradually more acidic.

“The resulting acidification will impact many forms of sea life, especially organisms whose shells or skeletons are made from , like corals and shellfish," he said.

It may interfere with the reproduction of plankton species which are a vital part of the on which fish and all other sea life depend.”

The scientists say there is now persuasive evidence that mass extinctions in past Earth history, like the “Great Dying” of 251 million years ago and another wipeout 55 million years ago, were accompanied by ocean acidification, which may have delivered the deathblow to many species that were unable to adapt.

“These past periods can serve as great lessons of what we can expect in the future, if we continue to push the acidity the ocean even further,” said the lead author, Dr Carles Pelejero, from ICREA (Catalan Institute for Research and Advanced Studies) and the Marine Science Institute of CSIC (Spanish National Research Council) in Barcelona, Spain.

“Given the impacts we see in the fossil record, there is no question about the need to immediately reduce the rate at which we are emitting carbon dioxide in the atmosphere,” he said.

“Today, the surface waters of the oceans have already acidified by an average of 0.1 pH units from pre-industrial levels, and we are seeing signs of its impact even in the deep oceans”, said co-author Dr Eva Calvo, from the Marine Science Institute of CSIC in Barcelona, Spain.

“Future acidification depends on how much CO2 humans emit from here on - but by the year 2100 various projections indicate that the oceans will have acidified by a further 0.3 to 0.4 pH units, which is more than many organisms like corals can stand”, Professor Hoegh-Guldberg said.

“This will create conditions not seen on Earth for at least 40 million years.

“These changes are taking place at rates as much as 100 times faster than they ever have over the last tens of millions of years,” Professor Hoegh-Guldberg said.

Under such circumstances, conditions are likely to become very hostile for calcifying species in the north Atlantic and Pacific over the next decade and in the Southern Ocean over the next few decades, the researchers warned.

Besides directly impacting on the fishing industry and its contribution to the human food supply at a time when global food demand is doubling, a major die-off in the oceans would affect birds and many land species and change the biology of Earth as a whole profoundly, Professor Hoegh-Guldberg said.

Palaeo-perspectives on ocean acidification by Carles Pelejero, Eva Calvo and Ove Hoegh-Guldberg is published in the latest issue of the journal Trends in Ecology and Evolution (TREE), number 1232.

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Citation: 'Evil twin' threatens world oceans, scientists warn (2010, March 29) retrieved 16 July 2019 from https://phys.org/news/2010-03-evil-twin-threatens-world-oceans.html
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Mar 29, 2010
This will be jumped on quickly by those who pretend to know more than the scientists, and those with a wingnut agenda.

Mar 29, 2010
Great way to intimidate skeptics before they even post. If people would just use the scientific method (both sides) there'd be a lot less of this "negative campaigning".

Mar 29, 2010
Unfortunately those who don't understand Science, don't understand what the scientific method is.

The Scientific Method can be though of as: Attack an idea on all sides, throwing everything you've got at disproving it and it's supporting evidence. Don't stop this process. Ever.

The ones left standing we call Science.

Science is ever-evolving and improving, but nothing is called Science that can in any way be or has ever been disproven. That something which is now called Science may not be Science in the future, does not open the door for that which cannot be proved now.

Mar 29, 2010
Its not just change , its the rate of change that's worrying. Evolution cannot keep pace with change in environment that is too rapid. We could get a great dieing off of diversity and simpler less robust, less productive ecosystems.

Mar 30, 2010
Its not just change , its the rate of change that's worrying. Evolution cannot keep pace with change in environment that is too rapid. We could get a great dieing off of diversity and simpler less robust, less productive ecosystems.

The opposite of this is the greatest argument against warmist propaganda, there has been greater and faster (sometimes together) changes in the past. Present changes are NOT unique and warming is FAR more desireable than cooling.
There has been much higher CO2 concentrations in the past and ocean life has survived and plant life multipied. We should be more concerned about the physical removing and altering of habitats than a bit of CO2 which is benifitial.

Mar 30, 2010
Present changes are NOT unique

It's not the change that may be catastrophic, but the RATE of change.

A rate of change like the current warming trend exceeds most advanced organnisms ablilty to cope through evolution. In the past, such rapid changes have resulted in mass extinctions. These extinctions may not only have been a direct result of these changes, but an indirect result as well, as the food supply decreases and eventually vanishes.

BTW, I saw a very interesting presentation on UCTV (University of California) once, linking global temperatures to population levels. The gist of the presentation was that increased population levels more than any other factor had the greatest impact on global temperature. And the ONLY effective way to reduce global warming is through birth control.

(Somehow I imagine that various conservative religious factions (Christian as well as Muslim,) would manage to squelch that kind of thinking.)

Mar 30, 2010
Is this study robust?

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