Subscribe free to our newsletters via your
. Space Industry and Business News .




ICE WORLD
A cataclysmic event of a certain age
by Staff Writers
Santa Barbara CA (SPX) Jul 29, 2015


This map shows the Younger Dryas Boundary locations that provided data for the analysis. Image courtesy UCSB.

At the end of the Pleistocene period, some 13,000 years ago a cosmic impact triggered an abrupt cooling episode that earth scientists refer to as the Younger Dryas. New research by UC Santa Barbara geologist James Kennett and an international group of investigators has narrowed the date to a 100-year range, sometime between 12,835 and 12,735 years ago. The team's findings appear in the Proceedings of the National Academy of Sciences.

The researchers used Bayesian statistical analyses of 354 dates taken from 30 sites on more than four continents. By using Bayesian analysis, the researchers were able to calculate more robust age models through multiple, progressive statistical iterations that consider all related age data.

"This range overlaps with that of a platinum peak recorded in the Greenland ice sheet and of the onset of the Younger Dryas climate episode in six independent key records," explained Kennett, professor emeritus in UCSB's Department of Earth Science. "This suggests a causal connection between the impact event and the Younger Dryas cooling."

In a previous paper, Kennett and colleagues conclusively identified a thin layer called the Younger Dryas Boundary (YDB) that contains a rich assemblage of high-temperature spherules, melt-glass and nanodiamonds, the production of which can be explained only by cosmic impact. However, in order for the major impact theory to be possible, the YDB layer would have to be the same age globally, which is what this latest paper reports.

"We tested this to determine if the dates for the layer in all of these sites are in the same window and statistically whether they come from the same event," Kennett said. "Our analysis shows with 95 percent probability that the dates are consistent with a single cosmic impact event."

All together, the locations cover a huge range of distribution, reaching from northern Syria to California and from Venezuela to Canada. Two California sites are on the Channel Islands off Santa Barbara.

However, Kennett and his team didn't rely solely on their own data, which mostly used radiocarbon dating to determine date ranges for each site. They also examined six instances of independently derived age data that used other dating methods, in most cases counting annual layers in ice and lake sediments.

Two core studies taken from the Greenland ice sheet revealed an anomalous platinum layer, a marker for the YDB. A study of tree rings in Germany also showed evidence of the YDB, as did freshwater and marine varves, the annual laminations that occur in bodies of water. Even stalagmites in China displayed signs of abrupt climate change around the time of the Younger Dryas cooling event.

"The important takeaway is that these proxy records suggest a causal connection between the YDB cosmic impact event and the Younger Dryas cooling event," Kennett said. "In other words, the impact event triggered this abrupt cooling.

"The chronology is very important because there's been a long history of trying to figure out what caused this anomalous and enigmatic cooling," he added. "We suggest that this paper goes a long way to answering that question and hope that this study will inspire others to use Bayesian statistical analysis in similar kinds of studies because it's such a powerful tool."


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only


.


Related Links
University of California - Santa Barbara
Beyond the Ice Age






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








ICE WORLD
Mammoths killed by abrupt climate change
Adelaide, Australia (SPX) Jul 28, 2015
New research has revealed abrupt warming, that closely resembles the rapid man-made warming occurring today, has repeatedly played a key role in mass extinction events of large animals, the megafauna, in Earth's past. Using advances in analysing ancient DNA, radiocarbon dating and other geologic records an international team led by researchers from the University of Adelaide and the Univer ... read more


ICE WORLD
Cages offer new direction in sustainable catalyst design

Controlling phase changes in solids

Researchers predict material with record-setting melting point

World's most powerful laser fired in Japan

ICE WORLD
Harris replacing satellite communications terminals

Lockheed Martin set to advance RF sensors development

Navy engineer invents new data transmission system

Fourth MUOS arrives in Florida for August launch

ICE WORLD
Payload fit-check for next Ariane 5 mission

SMC goes "2-for-2" on weather delayed launch

China tests new carrier rocket

Arianespace inaugurates new fueling facility for Soyuz upper stage

ICE WORLD
Russia develops national high-end navigation system

ISRO is hoping its 'BIG' offering would gain popularity in the market

China launches two satellites as it builds GPS rival

Russia, Brazil to track space junk with GLONASS

ICE WORLD
US delivers F-16s to Egypt ahead of Kerry visit: embassy

Engine fed steady diet of volcanic ash

Could 'Windbots' Someday Explore the Skies of Jupiter?

Harris enhancing targeting capabilities Navy aircraft

ICE WORLD
Quantum networks: Back and forth are not equal distances

New chiral property of silicon, with photonic applications found

New type of modulator for the future of data transmission

This could replace your silicon computer chips

ICE WORLD
NASA satellite images Alaska's scorched earth

California 'Rain Debt' Equal to Average Full Year of Precipitation

Space-eye-view could help stop global wildlife decline

Satellites peer into rock 50 miles beneath Tibetan Plateau

ICE WORLD
Playing 'tag' with pollution lets scientists see who's 'it'

Synthetic coral could remove toxic heavy metals from the ocean

Degrading BPA with visible light and a new hybrid photocatalyst

Researchers discover how to cut worrying levels of arsenic




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.