Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study Offers Preview of Ice Sheet Melting, Rapid Climate Changes

15.03.2006


The main extents of the Scandinavian Ice Sheet are shown in this digital elevation model of the sampling area outlined in gray. The letters and triangles represent different sampling sites. Image credit: adapted from The Land Processes Distributed Active Archive Center


Behavior of Scandinavian Ice Sheet at the end of the last Ice Age may preview loss of Greenland Ice Sheet due to global warming

The retreat of a massive ice sheet that once covered much of northern Europe has been described for the first time, and researchers believe it may provide a sneak preview of how present-day ice sheets in Greenland and Antarctica will act in the face of global warming.

The study, which appears in the current issue of the journal Science, was led by researchers from the Lamont-Doherty Earth Observatory and Oregon State University and contributed to by scientists from eight European institutes. They conclude that ice sheets in different parts of the world can react quite differently as the Earth warms.



"When we look at the Scandinavian Ice Sheet, we sometimes see it actually growing larger and sometimes rapidly disappearing, depending on whether increased snow offsets melting effects or not," said Vincent Rinterknecht, a post-doctoral research scientist at Lamont-Doherty Earth Observatory who is the study’s lead author and who conducted much of the research while he was a doctoral student at Oregon State. "Our work showed that it actually grew for a long period while the climate was warming but still very cold, and then rapidly disintegrated once the climate warmed even further."

The authors say the same dynamics of climate change and ice sheet growth may be at work today and probably mean that in the face of future global warming, ice across large portions of Antarctica may actually increase volume, but not at a rate that will counterbalance projected losses to the massive Greenland ice sheet. By itself, and without any offsetting mechanisms, a collapse of the Greenland ice sheet would raise global sea levels by about 20 to 25 feet. There is also concern that the rapid injection of large amounts of fresh water into this part of the North Atlantic Ocean may interfere with the ocean circulation system that is responsible for keeping much of Europe warm.

The timing of the ice sheet’s retreat has, until now, been poorly understood because of the relatively few radiocarbon dated sites in the region. In their study, the researchers used a technique to determine the time that rocks have been exposed to cosmic rays from outer space, which pass through the Earth’s atmosphere but cannot penetrate ice to any great depth. Using the method, known as cosmogenic surface exposure dating, Rinterknecht and his colleagues measured the amount of an isotope of the element beryllium, 10Be, formed when cosmic rays strike the surface of a rock. Knowing the rate at which 10Be forms and decays allowed the scientists to accurately determine how long a rock surface has been exposed and, therefore, when the ice sheet likely retreated.

The huge Scandinavian Ice Sheet the scientists studied once covered much of Northern Europe and formed during the most recent Ice Age, which lasted from about 100,000 to 10,000 years ago. At its peak it was about 6,000 feet thick and, after the ice sheet in North America, was the largest in the Northern Hemisphere. The researchers combined climate information, largely obtained from ice cores drilled in Greenland, with sea level records and records of deep-sea sediments to create a larger picture of how the ice sheet fluctuated within a changing climate.

The study was supported by the National Science Foundation’s Paleoclimate Program and the French Institut National de Physique Nuclèaire et de Physique de Particules and Institut National des Sciences de l’Univers.

The Earth Institute at Columbia University is the world’s leading academic center for the integrated study of Earth, its environment and society. The Earth Institute builds upon excellence in the core disciplines — earth sciences, biological sciences, engineering sciences, social sciences and health sciences — and stresses cross-disciplinary approaches to complex problems. Through research, training and global partnerships, it mobilizes science and technology to advance sustainable development, while placing special emphasis on the needs of the world’s poor. For more information, visit www.earth.columbia.edu.

The Lamont-Doherty Earth Observatory, a member of The Earth Institute at Columbia University, is one of the world’s leading research centers seeking fundamental knowledge about the origin, evolution and future of the natural world. More than 200 research scientists study the planet from its deepest interior to the outer reaches of its atmosphere, on every continent and in every ocean. From global climate change to earthquakes, volcanoes, nonrenewable resources, environmental hazards and beyond, Observatory scientists provide a rational basis for the difficult choices facing humankind in the planet’s stewardship.

Ken Kostel | EurekAlert!
Further information:
http://www.ldeo.columbia.edu
http://www.columbia.edu
http://www.earth.columbia.edu

More articles from Ecology, The Environment and Conservation:

nachricht Litter is present throughout the world’s oceans: 1,220 species affected
27.03.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

nachricht International network connects experimental research in European waters
21.03.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

'On-off switch' brings researchers a step closer to potential HIV vaccine

30.03.2017 | Health and Medicine

Penn studies find promise for innovations in liquid biopsies

30.03.2017 | Health and Medicine

An LED-based device for imaging radiation induced skin damage

30.03.2017 | Medical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>