Featured Research

from universities, journals, and other organizations

New understanding to past global warming events: Hyperthermal events may be triggered by warming

Date:
April 2, 2012
Source:
University of New Hampshire
Summary:
A series of global warming events called hyperthermals that occurred more than 50 million years ago had a similar origin to a much larger hyperthermal of the period, the Pelaeocene-Eocene Thermal Maximum (PETM), new research has found. The findings represent a breakthrough in understanding the major "burp" of carbon, equivalent to burning the entire reservoir of fossil fuels on Earth, that occurred during the PETM. The work confirms that the PETM was not a unique event - the result, perhaps, of a meteorite strike - but a natural part of Earth's carbon cycle.

These geological deposits make the Bighorn Basin area of Wyoming ideal for studying the PETM.
Credit: Aaron Diefendorf

A series of global warming events called hyperthermals that occurred more than 50 million years ago had a similar origin to a much larger hyperthermal of the period, the Pelaeocene-Eocene Thermal Maximum (PETM), new research has found. The findings, published in Nature Geoscience online on April 1, 2012, represent a breakthrough in understanding the major "burp" of carbon, equivalent to burning the entire reservoir of fossil fuels on Earth, that occurred during the PETM.

"As geologists, it unnerves us that we don't know where this huge amount of carbon released in the PETM comes from," says Will Clyde, associate professor of Earth sciences at the University of New Hampshire and a co-author on the paper. "This is the first breakthrough we've had in a long time. It gives us a new understanding of the PETM." The work confirms that the PETM was not a unique event - the result, perhaps, of a meteorite strike - but a natural part of Earth's carbon cycle.

Working in the Bighorn Basin region of Wyoming, a 100-mile-wide area with a semi-arid climate and stratified rocks that make it ideal for studying the PETM, Clyde and lead author Hemmo Abels of Utrecht University in the Netherlands found the first evidence of the smaller hyperthermal events on land. Previously, the only evidence of such events were from marine records.

"By finding these smaller hyperthermal events in continental records, it secures their status as global events, not just an ocean process. It means they are atmospheric events," Clyde says.

Their findings confirm that, like the smaller hyperthermals of the era that released carbon into the atmosphere, the release of carbon in the PETM had a similar origin. In addition, the warming-to-carbon release of the PETM and the other hyperthermals are similarly scaled, which the authors interpret as an indication of a similar mechanism of carbon release during all hyperthermals, including the PETM.

"It points toward the fact that we're dealing with the same source of carbon," Clyde says.

Working in two areas of the Bighorn Basin just east of Yellowstone National Park - Gilmore Hill and Upper Deer Creek - Clyde and Abels sampled rock and soil to measure carbon isotope records. They then compared these continental recordings of carbon release to equivalent marine records already in existence.

During the PETM, temperatures rose between five and seven degrees Celsius in approximately 10,000 years -- "a geological instant," Clyde calls it. This rise in temperature coincided exactly with a massive global change in mammals, as land bridges opened up connecting the continents. Prior to the PETM, North America had no primates, ancient horses, or split-hoofed mammals like deer or cows.

Scientists look to the PETM for clues about the current warming of Earth, although Clyde cautions that "Earth 50 million years ago was very different than it is today, so it's not a perfect analog." While scientists still don't fully understand the causes of these hyperthermal events, "they seem to be triggered by warming," Clyde says. It's possible, he says, that less dramatic warming events destabilized these large amounts of carbon, releasing them into the atmosphere where they, in turn, warmed the Earth even more.

"This work indicates that there is some part of the carbon cycle that we don't understand, and it could accentuate global warming," Clyde says.


Story Source:

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


Journal Reference:

  1. Hemmo A. Abels, William C. Clyde, Philip D. Gingerich, Frederik J. Hilgen, Henry C. Fricke, Gabriel J. Bowen, Lucas J. Lourens. Terrestrial carbon isotope excursions and biotic change during Palaeogene hyperthermals. Nature Geoscience, 2012; DOI: 10.1038/ngeo1427

Cite This Page:

University of New Hampshire. "New understanding to past global warming events: Hyperthermal events may be triggered by warming." ScienceDaily. ScienceDaily, 2 April 2012. <www.sciencedaily.com/releases/2012/04/120402124442.htm>.
University of New Hampshire. (2012, April 2). New understanding to past global warming events: Hyperthermal events may be triggered by warming. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2012/04/120402124442.htm
University of New Hampshire. "New understanding to past global warming events: Hyperthermal events may be triggered by warming." ScienceDaily. www.sciencedaily.com/releases/2012/04/120402124442.htm (accessed July 23, 2014).

Share This




More Earth & Climate News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Observation Boat to Protect Cetaceans During Ship Transfer

Observation Boat to Protect Cetaceans During Ship Transfer

AFP (July 22, 2014) As part of the 14-ship convoy that will accompany the Costa Concordia from the port of Giglio to the port of Genoa, there will be a boat carrying experts to look out for dolphins and whales from crossing the path of the Concordia. Duration: 01:02 Video provided by AFP
Powered by NewsLook.com
New Orleans Plans to Recycle Cigarette Butts

New Orleans Plans to Recycle Cigarette Butts

AP (July 21, 2014) New Orleans is the first U.S. city to participate in a large-scale recycling effort for cigarette butts. The city is rolling out dozens of containers for smokers to use when they discard their butts. (July 21) Video provided by AP
Powered by NewsLook.com
Shark Sightings a Big Catch for Cape Tourism

Shark Sightings a Big Catch for Cape Tourism

AP (July 21, 2014) A rise in shark sightings along the shores of Chatham, Massachusetts is driving a surge of eager vacationers to the beach town looking to catch a glimpse of a great white. (July 21) Video provided by AP
Powered by NewsLook.com
Spectacular Lightning Storm Hits London

Spectacular Lightning Storm Hits London

AFP (July 19, 2014) A spectaCular lightning storm struck the UK overnight Friday. Images of lightning strikes over the Shard and Tower Bridge in central London. Duration: 00:23 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