Featured Research

from universities, journals, and other organizations

Cosmic Dust In Ice Cores Sheds Light On Earth's Past Climate

Date:
July 28, 2006
Source:
The Earth Institute at Columbia University
Summary:
Each year nearly 40,000 tons of cosmic dust fall to Earth from outer space. The first successful chronological study of extraterrestrial dust in Antarctic ice has shown that this amount has remained largely constant over the past 30,000 years, a finding that could help refine efforts to understand the timing and effects of changes in the Earth's past climate.

The antarctic ice cap ia a perfect archive for precipitation and dust particles. Therefore even with blue sky you find precipitation of ice particles at Kohnen station in Antartica which can build a halo. Besides terrestrical mineral dust also extraterrestrical dust is deposed. On the top left a extraterrestrical dust particle of a few micrometers size is installed.
Credit: Johannes Freitag & Hubertus Fischer, Alfred Wegener Institute

Each year nearly 40,000 tons of cosmic dust fall to Earth from outer space. Now, the first successful chronological study of extraterrestrial dust in Antarctic ice has shown that this amount has remained largely constant over the past 30,000 years, a finding that could help refine efforts to understand the timing and effects of changes in the Earth's past climate. The same study also used an improved analytical technique to show that dust carried to Antarctica from continental sources changed depending on climate.

Related Articles


The study, which appears in the July 28 issue of the journal Science, involved researchers from the Lamont-Doherty Earth Observatory, a part of The Earth Institute at Columbia University, and the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, Germany. The depth of the core they examined corresponded to the period between 6,800 and 29,000 years before the present day--a span that includes the height of the last glacial period, and the transition to warm conditions similar to today.

The scientists collected particulate matter from the EPICA (European Project for Ice Coring in Antarctica) ice core and measured the concentration of helium-3 (3He), a rare isotope that is plentiful in the sun's solar wind and is carried to Earth imbedded in cosmic dust particles measuring just a few thousandths of a millimeter in diameter. These dust particles carry their exotic helium load to the Earth's surface where they are preserved in the snow and ice of the polar ice caps, among other places.

Because ice cores from the polar caps provide a high-resolution temporal record of the past, the researchers were able to measure fine variations in the rate of cosmic dust accumulation between glacial and interglacial periods as well as the helium isotope characteristics of these rare particles. They found that the accumulation of cosmic dust did not change appreciably as the Earth emerged from the last great Ice Age and entered the current warm period, a fact that is likely to bolster the use of cosmic dust measuring techniques in future climate studies.

In addition, this was the first study to examine both cosmic and terrestrial dust using the same helium-isotope technique. As a result, they also found that the composition of mineral dust particles carried by wind from the southern continents to Antarctica changed considerably as the Earth's climate changed.

"The terrestrial dust coming down on Antarctica during the Ice Age obviously is not the same as that during warm periods," said Gisela Winckler, a Doherty associate research scientist at Lamont-Doherty and lead author on the study. "This may be due to the mineral dust originating from different regional sources or to changes in the process responsible for producing the dust."

The project was supported by the Comer Science and Education Foundation.


Story Source:

The above story is based on materials provided by The Earth Institute at Columbia University. Note: Materials may be edited for content and length.


Cite This Page:

The Earth Institute at Columbia University. "Cosmic Dust In Ice Cores Sheds Light On Earth's Past Climate." ScienceDaily. ScienceDaily, 28 July 2006. <www.sciencedaily.com/releases/2006/07/060727180833.htm>.
The Earth Institute at Columbia University. (2006, July 28). Cosmic Dust In Ice Cores Sheds Light On Earth's Past Climate. ScienceDaily. Retrieved April 1, 2015 from www.sciencedaily.com/releases/2006/07/060727180833.htm
The Earth Institute at Columbia University. "Cosmic Dust In Ice Cores Sheds Light On Earth's Past Climate." ScienceDaily. www.sciencedaily.com/releases/2006/07/060727180833.htm (accessed April 1, 2015).

Share This


More From ScienceDaily



More Fossils & Ruins News

Wednesday, April 1, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Giant Amphibian Fossils Found in Portugal

Giant Amphibian Fossils Found in Portugal

Reuters - Light News Video Online (Mar. 31, 2015) — Scientists discover a new species of giant amphibian that was one of the largest predators on earth about 220 million year ago. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
Ancient Egyptian Beer Making Vessels Discovered in Israel

Ancient Egyptian Beer Making Vessels Discovered in Israel

AFP (Mar. 30, 2015) — Fragments of pottery used by Egyptians to make beer and dating back 5,000 years have been discovered on a building site in Tel Aviv, the Israeli Antiquities Authority said on Sunday. Duration: 00:51 Video provided by AFP
Powered by NewsLook.com
Party Like It's 3000 BC: Egyptian Beer Vessels Unearthed in Tel Aviv

Party Like It's 3000 BC: Egyptian Beer Vessels Unearthed in Tel Aviv

Reuters - Light News Video Online (Mar. 30, 2015) — Israeli archaeologists unearth ancient Egyptian beer vessels in downtown Tel Aviv. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
New Arthropod Fossil Might Be Relative Of Spiders, Scorpions

New Arthropod Fossil Might Be Relative Of Spiders, Scorpions

Newsy (Mar. 29, 2015) — A 508-million-year-old arthropod that swam in the Cambrian seas is thought to share a common ancestor with spiders and scorpions. Video provided by Newsy
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