Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers Rethink Massive Iceberg Shifts That Have Occurred In North Atlantic

16.01.2014
Some Heinrich events – periodic massive iceberg surges into the North Atlantic that were previously thought to have weakened the global ocean conveyor belt circulation and sent Earth’s climate into the deep freeze – may actually have been caused by changes in atmospheric circulation patterns, say a team of researchers that includes two Texas A&M University professors.

Matthew Schmidt, associate professor of oceanography, and Ping Chang, professor of oceanography and atmospheric science and director of the Texas Center for Climate Studies, along with colleagues from Georgia Tech, Princeton, the Woods Hole Oceanographic Institution, the University of Cambridge and Germany’s University of Bremen, have had their findings published in the latest issue of Nature Geoscience.

To make this discovery, the researchers studied the chemistry of shells produced by benthic foraminifera, single-celled organisms that live near the sea floor. These benthic foraminifera were collected from sediment cores recovered from the margins of the Florida Straits. By studying the oxygen isotope composition of the shells, the researchers were able to reconstruct past changes in Florida Current transport, which is directly related to the strength of the global conveyor belt circulation.

Researchers have known for years about Heinrich Events, periods of extreme cold in the North Atlantic. These events were named for the geologist who first discovered them, Hartmut Heinrich. They occurred during the last ice age when immense icebergs broke loose from glaciers, and as they melted, deposited ice rafted debris on the sea floor. Six of these Heinrich events have been identified, and they are known as H1 through H6.

“While there is evidence that the last Heinrich Event that occurred around 17,000 years ago was indeed caused by a dramatic reduction in the ocean’s conveyor belt circulation, our new reconstruction of ocean circulation patterns during some earlier Heinrich Events, that occurred during the last ice age between 20,000 and 30,000 years ago, did not reveal significant changes in ocean circulation,” Schmidt explains. “Nevertheless, these Heinrich Events were experienced worldwide, so they must have been transmitted via the atmosphere.”

Schmidt says that the study “has important implications for our understanding of the mechanisms of abrupt climate change in the past. The more we know about how climate changed in the past, the better prepared we will be for predicting future climate variability.”

Matthew Schmidt | Newswise
Further information:
http://www.tamu.edu

More articles from Earth Sciences:

nachricht Tundra study uncovers impact of climate warming in the Arctic
07.07.2015 | University of Edinburgh

nachricht NASA's infrared look at strengthening Typhoon Chan-Hom
07.07.2015 | NASA/Goddard Space Flight Center

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Surfing a wake of light

Researchers observe and control light wakes for the first time

When a duck paddles across a pond or a supersonic plane flies through the sky, it leaves a wake in its path. Wakes occur whenever something is traveling...

Im Focus: Light-induced Magnetic Waves in Materials Engineered at the Atomic Scale

Researchers explore ultrafast control of magnetism across interfaces: A new study discovers how the sudden excitation of lattice vibrations in a crystal can trigger a change of the magnetic properties of an atomically-thin layer that lies on its surface.

A research team, led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter at CFEL in Hamburg, the University of Oxford, and the...

Im Focus: Viaducts with wind turbines, the new renewable energy source

Wind turbines could be installed under some of the biggest bridges on the road network to produce electricity. So it is confirmed by calculations carried out by a European researchers team, that have taken a viaduct in the Canary Islands as a reference. This concept could be applied in heavily built-up territories or natural areas with new constructions limitations.

The Juncal Viaduct, in Gran Canaria, has served as a reference for Spanish and British researchers to verify that the wind blowing between the pillars on this...

Im Focus: X-rays and electrons join forces to map catalytic reactions in real-time

New technique combines electron microscopy and synchrotron X-rays to track chemical reactions under real operating conditions

A new technique pioneered at the U.S. Department of Energy's Brookhaven National Laboratory reveals atomic-scale changes during catalytic reactions in real...

Im Focus: Iron: A biological element?

Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and a half billion years ago.

Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

World Conference on Regenerative Medicine in Leipzig: Last chance to submit abstracts until 2 July

25.06.2015 | Event News

World Conference on Regenerative Medicine: Abstract Submission has been extended to 24 June

16.06.2015 | Event News

MUSE hosting Europe’s largest science communication conference

11.06.2015 | Event News

 
Latest News

Down to the quantum dot

07.07.2015 | Physics and Astronomy

Tundra study uncovers impact of climate warming in the Arctic

07.07.2015 | Earth Sciences

Transition from 3 to 2 dimensions increases conduction, MIPT scientists discover

07.07.2015 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>