Featured Research

from universities, journals, and other organizations

Climate Change Alters Ocean Chemistry

Date:
December 12, 2008
Source:
Carnegie Institution
Summary:
Scientists have discovered that the ocean's chemical makeup is less stable and more greatly affected by climate change than previously believed. The researchers report in Science that during a time of climate change 13 million years ago, the chemical makeup of the oceans changed dramatically. The researchers warn that the chemistry of the ocean today could be similarly affected by climate changes now underway, with potentially far-reaching consequences for marine ecosystems.

During a time of climate change 13 million years ago the chemical makeup of the oceans changed dramatically. Researchers warn that the chemical composition of the ocean today could be similarly affected by climate changes now underway -- with potentially far-reaching consequences for marine ecosystems.
Credit: Copyright Michele Hogan

Researchers have discovered that the ocean's chemical makeup is less stable and more greatly affected by climate change than previously believed. Researchers report that during a time of climate change 13 million years ago the chemical makeup of the oceans changed dramatically. The researchers warn that the chemical composition of the ocean today could be similarly affected by climate changes now underway – with potentially far-reaching consequences for marine ecosystems.

"As CO2 increases and weather patterns shift, the chemical composition of our rivers will change, and this will affect the oceans," says co-author Ken Caldeira of the Carnegie Institution's Department of Global Ecology. "This will change the amount of calcium and other elements in ocean salts."

The research team, which included Caldeira, Elizabeth M. Griffith and Adina Paytan of the University of California, Santa Cruz, plus two other colleagues, studied core samples of deep oceanic sediment recovered from the Pacific Ocean Basin. By analyzing the calcium isotopes in grains of the mineral barite in different layers, they determined that between 13 and 8 million years ago the ocean's calcium levels shifted dramatically. The shift corresponds to the growth of the Antarctic ice sheets during the same time interval. Because of the huge volume of water that became locked up in the ice cap, sea level also dropped.

"The climate got colder, ice sheets expanded, sea level dropped, and the intensity, type, and extent of weathering on land changed," explains Griffith.

"This caused changes in ocean circulation and in the amount and composition of what rivers delivered to the ocean," adds Paytan. "This in turn impacted the biology and chemistry of the ocean."

Calcium-bearing rocks such as limestone are the largest storehouse of carbon in the Earth's carbon cycle because they are primarily made up of calcium carbonate. "The ocean's calcium cycle is closely linked to atmospheric carbon dioxide and the processes that control seawater's acidity," says Caldeira. Acidification of seawater is already a growing threat to coral reefs and other marine life.

"What we learned from this work is that the ocean system is much more sensitive to climate change than we have previously appreciated," says Griffith. "We thought that the concentration of calcium, which is a major element in seawater, would change slowly and gradually over tens of millions of years. But what our data suggests is that there could be a more dynamic relationship between climate and ocean chemistry, which can sometimes result in rapid biogeochemical reorganization."

"We see here how dynamic the climate-ocean system is and that the responses to change are not always what we would expect" says Paytan. "We need to keep this in mind when considering future climate and other anthropogenic changes, like ocean acidification, and their impact on the ocean and ocean resources."


Story Source:

The above story is based on materials provided by Carnegie Institution. Note: Materials may be edited for content and length.


Journal Reference:

  1. Elizabeth M. Griffith, Adina Paytan, Ken Caldeira, Thomas D. Bullen and Ellen Thomas. A dynamic marine calcium cycle during the past 28 million years. Science, December 12, 2008

Cite This Page:

Carnegie Institution. "Climate Change Alters Ocean Chemistry." ScienceDaily. ScienceDaily, 12 December 2008. <www.sciencedaily.com/releases/2008/12/081211141832.htm>.
Carnegie Institution. (2008, December 12). Climate Change Alters Ocean Chemistry. ScienceDaily. Retrieved September 19, 2014 from www.sciencedaily.com/releases/2008/12/081211141832.htm
Carnegie Institution. "Climate Change Alters Ocean Chemistry." ScienceDaily. www.sciencedaily.com/releases/2008/12/081211141832.htm (accessed September 19, 2014).

Share This



More Earth & Climate News

Friday, September 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Wildfires in CA Burn Forest Asunder

Raw: Wildfires in CA Burn Forest Asunder

AP (Sep. 18, 2014) An out-of-control Northern California wildfire has nearly 2,800 people from their homes as it continues to grow, authorities said Thursday. Authorities said a man has been arrested on suspicion of arson for starting the fire on Saturday. (Sept. 18) Video provided by AP
Powered by NewsLook.com
Raw: Elephant Undergoes Surgery in Tbilisi Zoo

Raw: Elephant Undergoes Surgery in Tbilisi Zoo

AP (Sep. 18, 2014) Grand the elephant has successfully undergone surgery to remove a portion of infected tusk at Tbilisi Zoo in Georgia. British veterinary surgeons used an electric drill to extract the infected piece. (Sept. 18) Video provided by AP
Powered by NewsLook.com
Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Man Floats for 31 Hours in Gulf Waters

Man Floats for 31 Hours in Gulf Waters

AP (Sep. 16, 2014) A Texas man is lucky to be alive after he and three others floated for more than a day in the Gulf of Mexico when their boat sank during a fishing trip. (Sept. 16) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins