Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Oceans may soon be more corrosive than when the dinosaurs died

21.02.2006


Increased carbon dioxide emissions are rapidly making the world’s oceans more acidic and, if unabated, could cause a mass extinction of marine life similar to one that occurred 65 million years ago when the dinosaurs disappeared. Ken Caldeira of the Carnegie Institution’s Department of Global Ecology will present this research at the AGU/ASLO Ocean Sciences meeting in Honolulu, HI on Monday, Feb 20.

Caldeira’s computer models have predicted that the oceans will become far more acidic within the next century. Now, he has compared this data with ocean chemistry evidence from the fossil record, and has found some startling similarities. The new finding offers a glimpse of what the future might hold for ocean life if society does not drastically curb carbon dioxide emissions.

"The geologic record tells us the chemical effects of ocean acidification would last tens of thousands of years," Caldeira said. "But biological recovery could take millions of years. Ocean acidification has the potential to cause extinction of many marine species."



When carbon dioxide from the burning of coal, oil, and gas dissolves in the ocean, some of it becomes carbonic acid. Over time, accumulation of this carbonic acid makes ocean water more acidic. When carbonic acid input is modest, sediments from the ocean floor can buffer the increases in acidity. But at the current rate of input--nearly 50 times the natural background from volcanoes and other sources--this buffering mechanism is overwhelmed. Previous estimates suggest that in less than 100 years, the pH of the oceans could drop by as much as half a unit from its natural value of 8.2 to about 7.7. (On the pH scale, lower numbers are more acidic and higher numbers are more basic.)

This drop in ocean pH would be especially damaging to marine animals such as corals that use calcium carbonate to make their shells. Under normal conditions the ocean is supersaturated with this mineral, making it easy for such creatures to grow. However, a more acidic ocean would more easily dissolve calcium carbonate, putting these species at particular risk.

The last time the oceans endured such a drastic change in chemistry was 65 million years ago, at about the same time the dinosaurs went extinct. Though researchers do not yet know exactly what caused this ancient acidification, it was directly related to the cataclysm that wiped out the giant beasts. The pattern of extinction in the ocean is consistent with ocean acidification--the fossil record reveals a precipitous drop in the number of species with calcium carbonate shells that live in the upper ocean--especially corals and plankton. During the same period, species with shells made from resistant silicate minerals were more likely to survive.

The world’s oceans came close to an acidic catastrophe one other time about 55 million years ago, when the temperature of the Earth spiked and large amounts of methane and/or carbon dioxide flooded the atmosphere. There is no evidence, however, that this caused a mass extinction event.

"Ultimately, if we are not careful, our energy system could make the oceans corrosive to coral reefs and many other marine organisms," Caldeira cautions. "These results should help motivate the search for new energy sources, such as wind and solar, that can fuel economic growth without releasing dangerous carbon dioxide into the environment."

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

More articles from Ecology, The Environment and Conservation:

nachricht Safeguarding sustainability through forest certification mapping
27.06.2017 | International Institute for Applied Systems Analysis (IIASA)

nachricht Dune ecosystem modelling
26.06.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

Im Focus: Laser-cooled ions contribute to better understanding of friction

Physics supports biology: Researchers from PTB have developed a model system to investigate friction phenomena with atomic precision

Friction: what you want from car brakes, otherwise rather a nuisance. In any case, it is useful to know as precisely as possible how friction phenomena arise –...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

NASA looks to solar eclipse to help understand Earth's energy system

21.07.2017 | Earth Sciences

Stanford researchers develop a new type of soft, growing robot

21.07.2017 | Power and Electrical Engineering

Vortex photons from electrons in circular motion

21.07.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>