Google Play icon

Rapidly acidifying waters pose major threat for Southern Ocean ecosystem

Share
Posted November 6, 2015

As a result of increasing atmospheric carbon dioxide concentrations, the chemistry of the Southern Ocean is expected to change so fast over the next few decades that tiny creatures at the base of the food web may soon struggle to form their shells. New research by scientists from the University of Hawaiʻi at Mānoa and the University of Alaska, Fairbanks (UAF) finds that for some organisms the onset of such critical conditions will be so abrupt, and the duration of events so long, that adaption may become impossible.

Duration of harmful surface events for today, 2055 and 2095. Inset: Example of pteropod showing in situ dissolution due to ocean acidification. Image credit: Nina Bednarsek, NOAA

Duration of harmful surface events for today, 2055 and 2095. Inset: Example of pteropod showing in situ dissolution due to ocean acidification. Image credit: Nina Bednarsek, NOAA

The study, published in the journal Nature Climate Change, uses a number of Earth system models to explore how the uptake of human-induced carbon dioxide and the resulting ocean acidification will affect the Southern Ocean over the next century.

Chemistry changes affect sea life

“The ocean acts as a gigantic sponge to absorb excess carbon dioxide from the atmosphere. This process consumes carbonate ions, which are required by key organisms to build and maintain their calcium carbonate shells. If the carbonate ion concentration drops below a threshold—we call it undersaturation—these organisms must spend more energy to fight dissolution in these adverse chemical conditions,” explains Claudine Hauri, lead author of the study and a chemical oceanographer at both the International Artic Research Center at UAF and the International Pacific Research Center (IPRC) at UH Mānoa.

One of the most threatened marine organisms is the pteropod, a tiny sea snail that serves as a staple for plankton, fish, whales and seabirds.

Models raise red flags

Not only is the concentration of carbonate ions projected to fall to dangerously low levels due to ocean acidification, but these conditions will become the new norm across large areas of the Southern Ocean.

“Our analysis shows that in large parts of the Southern Ocean, the duration of such undersaturation events will increase abruptly from one month to more than six months, in less than 20 years upon their onset, and could reach nearly year-long durations by the end of the century,” notes co-lead author Tobias Friedrich, climate scientist atIPRC.

“This is a clear warning sign. Given the projected rapid expansion and prolongation of these harmful conditions, it remains very uncertain whether pteropods and other vulnerable marine organisms will be able to adapt,” adds Hauri.

“The only way to mitigate the risks of ocean acidification to marine life and our food supply is to curb our carbon dioxide emissions,” said Axel Timmermann, co-author of the study and oceanography professor at IPRC.

Source: NSF, University of Hawaii at Manoa

Featured news from related categories:

Technology Org App
Google Play icon
85,577 science & technology articles

Most Popular Articles

  1. New treatment may reverse celiac disease (October 22, 2019)
  2. The World's Energy Storage Powerhouse (November 1, 2019)
  3. "Helical Engine" Proposed by NASA Engineer could Reach 99% the Speed of Light. But could it, really? (October 17, 2019)
  4. Universe is a Sphere and Not Flat After All According to a New Research (November 7, 2019)
  5. ‘Artificial leaf’ successfully produces clean gas (October 22, 2019)

Follow us

Facebook   Twitter   Pinterest   Tumblr   RSS   Newsletter via Email