Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Coral reefs may start dissolving when atmospheric CO2 doubles

11.03.2009
Rising carbon dioxide in the atmosphere and the resulting effects on ocean water are making it increasingly difficult for coral reefs to grow, say scientists.

A study to be published online March 13, 2009 in Geophysical Research Letters by researchers at the Carnegie Institution and the Hebrew University of Jerusalem warns that if carbon dioxide reaches double pre-industrial levels, coral reefs can be expected to not just stop growing, but also to begin dissolving all over the world.

The impact on reefs is a consequence of both ocean acidification caused by the absorption of carbon dioxide into seawater and rising water temperatures. Previous studies have shown that rising carbon dioxide will slow coral growth, but this is the first study to show that coral reefs can be expected to start dissolving just about everywhere in just a few decades, unless carbon dioxide emissions are cut deeply and soon.

"Globally, each second, we dump over 1000 tons of carbon dioxide into the atmosphere and, each second, about 300 tons of that carbon dioxide is going into the oceans," said co-author Ken Caldeira of the Carnegie Institution's Department of Global Ecology, testifying to the U.S. House of Representatives Subcommittee on Insular Affairs, Oceans and Wildlife of the Committee on Natural Resources on February 25, 2009. "We can say with a high degree of certainty that all of this CO2 will make the oceans more acidic – that is simple chemistry taught to freshman college students."

The study was designed determine the impact of this acidification on coral reefs. The research team, consisting of Jacob Silverman, Caldeira, and Long Cao of the Carnegie Institution as well as Boaz Lazar and Jonathan Erez from The Hebrew University of Jerusalem, used field data from coral reefs to determine the effects of temperature and water chemistry on coral calcification rates. Armed with this information, they plugged the data into a computer model that calculated global seawater temperature and chemistry at different atmospheric levels of CO2 ranging from the pre-industrial value of 280 ppm (parts per million) to 750 ppm. The current atmospheric concentration is over 380 ppm, and is rapidly rising due to human-caused emissions, primarily through the burning of fossil fuels.

Based on the model results for more than 9,000 reef locations, the researchers determined that at the highest concentration studied, 750 ppm, acidification of seawater would reduce calcification rates of three quarters of the world's reefs to less than 20% of pre-industrial rates. Field studies suggest that at such low rates, coral growth would not be able to keep up with dissolution and other natural as well as manmade destructive processes attacking reefs.

Prospects for reefs are even gloomier when the effects of coral bleaching are included in the model. Coral bleaching refers to the loss of symbiotic algae that are essential for healthy growth of coral colonies. Bleaching is already a widespread problem, and high temperatures are among the factors known to promote bleaching. According to their model the researchers calculated that under present conditions 30% of reefs have already undergone bleaching and that at CO2 levels of 560 ppm (twice pre-industrial levels) the combined effects of acidification and bleaching will reduce the calcification rates of all the world's reefs by 80% or more. This lowered calcification rate will render all reefs vulnerable to dissolution, without even considering other threats to reefs, such as pollution.

"Our fossil-fueled lifestyle is killing off coral reefs," says Caldeira. "If we don't change our ways soon, in the next few decades we will destroy what took millions of years to create."

"Coral reefs may be the canary in the coal mine," he adds. "Other major pieces of our planet may be similarly threatened because we are using the atmosphere and oceans as dumps for our CO2 pollution. We can save the reefs if we decide to treat our planet with the care it deserves. We need to power our economy with technologies that do not dump carbon dioxide into the atmosphere or oceans."

Ken Caldeira | EurekAlert!
Further information:
http://www.ciw.edu

More articles from Earth Sciences:

nachricht Multi-year submarine-canyon study challenges textbook theories about turbidity currents
12.12.2017 | Monterey Bay Aquarium Research Institute

nachricht How do megacities impact coastal seas? Searching for evidence in Chinese marginal seas
11.12.2017 | Leibniz-Institut für Ostseeforschung Warnemünde

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

A whole-body approach to understanding chemosensory cells

13.12.2017 | Health and Medicine

Water without windows: Capturing water vapor inside an electron microscope

13.12.2017 | Physics and Astronomy

Cellular Self-Digestion Process Triggers Autoimmune Disease

13.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>