Featured Research

from universities, journals, and other organizations

Formation Of Ice Sheets 34 Million Years Ago Changed Ocean Acidity

Date:
April 29, 2008
Source:
University of Southampton
Summary:
Before ice first began to form in Antarctica around 34 million years ago, the Earth was a very different place - but then greenhouse conditions swiftly gave way to an icehouse climate, causing the oceans to become less acidic. Scientists have been piecing together how Earth's changing climate affected ocean chemistry during this period of transition. Their work sheds light on the links between glaciation and the ocean carbon cycle.

Before ice first began to form in Antarctica around 34 million years ago, the Earth was a very different place - but then greenhouse conditions swiftly gave way to an icehouse climate, causing the oceans to become less acidic.

Scientists at the University of Southampton's School of Ocean and Earth Science, based at the National Oceanography Centre, Southampton UK and Germany's GKSS Research Centre have been piecing together how Earth's changing climate affected ocean chemistry during this period of transition. Their work sheds light on the links between glaciation and the ocean carbon cycle.

Their research, published in Nature (24 April 2008), confirms the connection between two separate phenomena that occurred at the same time: a fall in sea-level caused by Antarctic glaciation and a change in ocean acidity - revealed by a change in the depth at which calcium carbonate shells start dissolving on the sea floor.

Dr Toby Tyrrell of the National Oceanography Centre, Southampton said:

"We were keen to discover why the oceans became suddenly less acidic - the reverse of what is happening today. Although the changes took place 34 million years ago, by understanding how the Earth System operated at this time of dramatic change we can gain insights as to how Earth will respond as we modify it by adding carbon dioxide from burning fuels."

The team used a global biogeochemical ocean model to test different explanations as to what was happening during the transition from the Eocene period - a time of warm greenhouse conditions with higher ocean acidity, to the Oligocene period - characterised by ice, cooler temperatures and lower ocean acidity.

Dr Tyrrell continued:

"This work has advanced our understanding of how the Earth System worked during this critical period. When most explanations were incorporated into our computer model, it produced results in conflict with the available data. Only one scenario was found to be compatible with the data."

Dr Tyrrell's colleague, Professor Paul Wilson also of the University of Southampton's School of Ocean and Earth Science said:

"Our work suggests that a fall in sea-level had the effect of leaving coral reefs stranded above the high-tide level where they were then eroded by wind and rain. Corals are composed of calcium carbonate - chalk - which reduces the acidity when it dissolves in seawater."

The third member of the team, Dr Agostino Merico, who is a former postdoctoral researcher at the National Oceanography Centre, Southampton and is now with the GKSS Research Centre in Geesthacht, said:

"With this powerful tool we can peer into the deep past to gain insights into arguably the most important climatic transition of the last 100 million years. With this work we have been able to put together different components and complex processes of the Earth System, and to relate them to each other. The whole point of a model is to abstract core ideas or hypothesis in a way that enables us to learn about them."


Story Source:

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


Cite This Page:

University of Southampton. "Formation Of Ice Sheets 34 Million Years Ago Changed Ocean Acidity." ScienceDaily. ScienceDaily, 29 April 2008. <www.sciencedaily.com/releases/2008/04/080428130641.htm>.
University of Southampton. (2008, April 29). Formation Of Ice Sheets 34 Million Years Ago Changed Ocean Acidity. ScienceDaily. Retrieved April 25, 2014 from www.sciencedaily.com/releases/2008/04/080428130641.htm
University of Southampton. "Formation Of Ice Sheets 34 Million Years Ago Changed Ocean Acidity." ScienceDaily. www.sciencedaily.com/releases/2008/04/080428130641.htm (accessed April 25, 2014).

Share This



More Earth & Climate News

Friday, April 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Fungus Killing Bats, Spreading in US

Deadly Fungus Killing Bats, Spreading in US

AP (Apr. 24, 2014) A disease that has killed more than six million cave-dwelling bats in the United States is on the move and wildlife biologists are worried. White Nose Syndrome, discovered in New York in 2006, has now spread to 25 states. (April 24) Video provided by AP
Powered by NewsLook.com
New Pictures of Ship That Sank in 1888

New Pictures of Ship That Sank in 1888

AP (Apr. 24, 2014) Federal researchers have released new images of the City of Chester, a steamship that sank in San Francisco Bay in 1888. Researchers recently found the shipwreck while mapping shipping routes. (April 24) Video provided by AP
Powered by NewsLook.com
Risk of Asteroid Hitting Earth Higher Than Thought, Study Shows

Risk of Asteroid Hitting Earth Higher Than Thought, Study Shows

Reuters - US Online Video (Apr. 23, 2014) A group of space explorers say the chance of a city-obliterating asteroid striking Earth is higher than scientists previously believed. Deborah Gembara reports. Video provided by Reuters
Powered by NewsLook.com
UN Joint Mission Starts Removing Landmines in Cyprus

UN Joint Mission Starts Removing Landmines in Cyprus

AFP (Apr. 23, 2014) The UN mission in Cyprus (UNFICYP) led a mine clearance demonstration on Wednesday in the UN-controlled buffer zone where demining operations are being conducted near the Cypriot village of Mammari. Duration: 01:00 Video provided by AFP
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