Featured Research

from universities, journals, and other organizations

The Dark Ages May Have Really Been Dimmer

Date:
January 4, 2001
Source:
Los Alamos National Laboratory
Summary:
The beginning of the Dark Ages may have been literal, as well as figurative, as the result of a massive volcanic eruption in the 6th century, according to a volcanologist at the Department of Energy's Los Alamos National Laboratory.

LOS ALAMOS, N.M., Dec. 17, 2000 -- The beginning of the Dark Ages may have been literal, as well as figurative, as the result of a massive volcanic eruption in the 6th century, according to a volcanologist at the Department of Energy's Los Alamos National Laboratory.

Related Articles


Ken Wohletz said an eruption in the Indonesian archipelago could have produced a 150-meter-thick cloud layer over the entire Earth, triggering a chain of climatic, agricultural, political and social changes that ushered in the Dark Ages.

Evidence supporting the catastrophe includes tree-ring and ice-core measurements, indications of a huge underwater caldera, and ash and pumice in the same area, said Wohletz, who discusses his work modeling such an eruption today (Dec. 17) at the fall meeting of the American Geophysical Union.

The 6th century was a turbulent, unsettling period in human history. The Roman Empire began to fall; nomads of central Asia migrated to Europe and the Near East; civilizations in Persia, Indonesia and South America collapsed; major religions experienced considerable change as natural events were viewed as omens.

Many of these social transformations resulted from widespread crop failures and the explosion of plague around the globe, which in turn were caused by major climatic changes, Wohletz said. Beginning in about the year 535, according to historical and archeological records, the weather was colder and drier, sunlight diminished, snow fell in summer and regions of persistent drought suffered floods.

Wohletz was a resource for a book postulating that the climate changes resulted from a huge volcanic eruption. The book, "Catastrophe: A Quest for the Origins of the Modern World" by David Keys, was published earlier this year.

Wohletz said he worked with Keys to try to identify a volcano that could produce such dramatic climate change. "We came up with an eruption that would certainly be the largest in recorded history, some four or five times bigger than the (1815) eruption of Tambora, which is usually considered the biggest eruption in the past few millennia," he said.

Such an explosion, he said, would eject some 200 cubic kilometers of material, and one-third to one-half of it would be lofted into the stratosphere, where it would remain suspended for months to years while being carried around the globe.

"It would have produced enough dust and water vapor (in the form of ice crystals) to form a cloud layer 150 meters thick over the entire globe, and that's a conservative estimate," he said, adding that a cloud of particles that thick may have diminished the transmission of sunlight by as much as 50 percent.

Wohletz said tree-ring data collected around the world and ice-core measurements in Greenland and Antarctica support the possibility of a huge eruption in the 6th century. Ocean depth measurements between Sumatra and Java where Krakatoa exploded in a well known 1883 eruption indicate the presence of a caldera up to 50 kilometers in diameter, and a recent survey uncovered evidence of ash and pumice layers formed in the area during the appropriate time frame.

Under a likely scenario, a large volcano, which Wohletz calls proto-Krakatoa, connected the islands of Sumatra and Java. When it erupted and then subsided, it created the Sundra Strait and left a ring of smaller volcanoes, including the present day Krakatoa. The ash, dust and water vapor blown into the stratosphere would disperse across both the Northern and Southern Hemispheres.

"This volcano would have had the potential to be a major player in destabilizing the climate around the world," he said. "An eruption that could produce a caldera 50 kilometers across would have been big enough."

Although definitive evidence for such a catastrophic eruption has not been discovered, the possibility deserves a full-scale field study, Wohletz said, in part because of the potential impact on the world if another such catastrophe happens.

"(Key's book) is the first detailed account of how closely humanity is linked to the natural world," he said. "If the natural world goes through some large upheaval, we'll all be affected."

Los Alamos National Laboratory is operated by the University of California for the U.S. Department of Energy.


Story Source:

The above story is based on materials provided by Los Alamos National Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

Los Alamos National Laboratory. "The Dark Ages May Have Really Been Dimmer." ScienceDaily. ScienceDaily, 4 January 2001. <www.sciencedaily.com/releases/2001/01/010102061812.htm>.
Los Alamos National Laboratory. (2001, January 4). The Dark Ages May Have Really Been Dimmer. ScienceDaily. Retrieved March 5, 2015 from www.sciencedaily.com/releases/2001/01/010102061812.htm
Los Alamos National Laboratory. "The Dark Ages May Have Really Been Dimmer." ScienceDaily. www.sciencedaily.com/releases/2001/01/010102061812.htm (accessed March 5, 2015).

Share This


More From ScienceDaily



More Earth & Climate News

Thursday, March 5, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Keurig Co-Founder Says Company Has A Waste Problem

Keurig Co-Founder Says Company Has A Waste Problem

Newsy (Mar. 5, 2015) Keurig co-founder John Sylvan told The Atlantic he doesn&apos;t even own a Keurig because they&apos;re too expensive and produce too much waste. Video provided by Newsy
Powered by NewsLook.com
Raw: Tourists Visit Rare Grey Whales in Mexico

Raw: Tourists Visit Rare Grey Whales in Mexico

AP (Mar. 4, 2015) Once nearly extinct, grey whales now migrate in their thousands to Mexico&apos;s Vizcaino reserve in Baja California, in search of warmer waters to mate and give birth. Tourists flock to the reserve to see the whales, measuring up to 49 feet long. (March 4) Video provided by AP
Powered by NewsLook.com
Raw: Injured Miners Treated After Blast

Raw: Injured Miners Treated After Blast

AP (Mar. 4, 2015) An explosion ripped through a coal mine before dawn Wednesday in war-torn eastern Ukraine, killing at least one miner, officials said. Graphic video of injured miners being treated in a Donetsk hospital. (March 4) Video provided by AP
Powered by NewsLook.com
Australian Museum Shares Terrifying Goblin Shark With the World

Australian Museum Shares Terrifying Goblin Shark With the World

Buzz60 (Mar. 4, 2015) The Australian Museum has taken in its fourth-ever goblin shark, a rare fish with an electricity-sensing snout and &apos;alien-like&apos; jaw. Mike Janela (@mikejanela) takes a look. Video provided by Buzz60
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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