Featured Research

from universities, journals, and other organizations

From Icehouse To Hothouse: Melting Ice And Rising Carbon Dioxide Caused Climate Shift

Date:
February 27, 2007
Source:
University of Michigan
Summary:
Three hundred million years ago, Earth's climate shifted dramatically from icehouse to hothouse, with major environmental consequences. That shift was the result of both rising atmospheric carbon dioxide concentrations and the melting of vast ice sheets, new research by University of Michigan paleoclimatologist Christopher Poulsen shows.

Three hundred million years ago, Earth's climate shifted dramatically from icehouse to hothouse, with major environmental consequences. That shift was the result of both rising atmospheric carbon dioxide concentrations and the melting of vast ice sheets, new research by University of Michigan paleoclimatologist Christopher Poulsen shows.

Poulsen will discuss his findings in a symposium titled "Geosystems: Climate Lessons from Earth's Last Great Icehouse" at the annual meeting of the American Association for the Advancement of Science in San Francisco.

The changes occurred during the period of Earth's history when the continents were consolidated into a single supercontinent, Pangaea. Toward the end of the Paleozoic Era, tropical regions of Pangaea became much warmer and drier, winds in the region shifted direction, and tropical flora drastically changed. At the same time, atmospheric carbon dioxide increased and the enormous ice sheets that blanketed Gondwana---the landmass that eventually broke up to become present-day South America, Africa, Antarctica, India and Australia---began disappearing.

"There's lots of evidence for large changes in climate and vegetation, but there's been no clear hypothesis for why those changes occurred," said Poulsen, who is an assistant professor of geological sciences. A few notions have been floating around: some researchers have suggested that the uplifting or erosion of mountain chains might have caused the climate shift; others think the motion of the plates that make up Earth's outer layer played a role. But Poulsen had a different idea. "I wondered whether the melting of the Gondwana ice sheets and/or the rise in atmospheric carbon dioxide could explain these documented climate and vegetation changes," he said.

Poulsen and coworkers used theoretical climate models to experiment with different combinations of carbon dioxide concentrations and glaciation.

"The modeling simulations showed that as Gondwana deglaciated and carbon dioxide rose, the tropics became more arid and the vegetation was fried and replaced with desert," Poulsen said. "Our results also showed that deglaciation and rising carbon dioxide contributed about equally to the observed climate and vegetation changes."

In addition, the model, which relied on estimates of carbon dioxide concentrations, produced more warming than geological evidence actually indicates. This may suggest that carbon dioxide didn't rise quite as much as has been estimated, Poulsen said.

Poulsen is cautious about applying his conclusions to current climate concerns.

"The climate change I'm studying happened a long time ago, so you have to be a little careful, but certainly this work shows there is a very strong connection between carbon dioxide increase and warming," he said. "Another interesting aspect is that for a long time people have thought that the tropics aren't really susceptible to large climate changes. This work shows that the tropics are susceptible."


Story Source:

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


Cite This Page:

University of Michigan. "From Icehouse To Hothouse: Melting Ice And Rising Carbon Dioxide Caused Climate Shift." ScienceDaily. ScienceDaily, 27 February 2007. <www.sciencedaily.com/releases/2007/02/070220011358.htm>.
University of Michigan. (2007, February 27). From Icehouse To Hothouse: Melting Ice And Rising Carbon Dioxide Caused Climate Shift. ScienceDaily. Retrieved April 17, 2014 from www.sciencedaily.com/releases/2007/02/070220011358.htm
University of Michigan. "From Icehouse To Hothouse: Melting Ice And Rising Carbon Dioxide Caused Climate Shift." ScienceDaily. www.sciencedaily.com/releases/2007/02/070220011358.htm (accessed April 17, 2014).

Share This



More Earth & Climate News

Thursday, April 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Change of Diet Helps Crocodile Business

Change of Diet Helps Crocodile Business

Reuters - Business Video Online (Apr. 16, 2014) Crocodile farming has been a challenge in Zimbabwe in recent years do the economic collapse and the financial crisis. But as Ciara Sutton reports one of Europe's biggest suppliers of skins to the luxury market has come up with an unusual survival strategy - vegetarian food. Video provided by Reuters
Powered by NewsLook.com
How Mt. Everest Helped Scientists Research Diabetes

How Mt. Everest Helped Scientists Research Diabetes

Newsy (Apr. 15, 2014) British researchers were able to use Mount Everest's low altitudes to study insulin resistance. They hope to find ways to treat diabetes. Video provided by Newsy
Powered by NewsLook.com
The Walking, Talking Oil-Drigging Rig

The Walking, Talking Oil-Drigging Rig

Reuters - Business Video Online (Apr. 15, 2014) Pennsylvania-based Schramm is incorporating modern technology in its next generation oil-drigging rigs, making them smaller, safer and smarter. Ernest Scheyder reports. Video provided by Reuters
Powered by NewsLook.com
In Washington, a Push to Sterilize Stray Cats

In Washington, a Push to Sterilize Stray Cats

AFP (Apr. 14, 2014) To curb the growing numbers of feral cats in the US capital, the Washington Humane Society is encouraging residents to set traps and bring the animals to a sterilization clinic, after which they are released.. Duration: 02:29 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