Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Baffin Island ice caps shrink by 50 percent since 1950s

30.01.2008
Researchers also find tantalizing evidence that ancient tropical eruptions of volcanoes triggered Little Ice Age

A new University of Colorado at Boulder study has shown that ice caps on the northern plateau of Baffin Island in the Canadian Arctic have shrunk by more than 50 percent in the last half century as a result of warming, and are expected to disappear by the middle of the century.

Radiocarbon dating of dead plant material emerging from beneath the receding ice margins show the Baffin Island ice caps are now smaller in area than at any time in at least the last 1,600 years, said geological sciences Professor Gifford Miller of CU-Boulder's Institute of Arctic and Alpine Research. "Even with no additional warming, our study indicates these ice caps will be gone in 50 years or less," he said.

The study also showed two distinct bursts of Baffin Island ice-cap growth commencing about 1280 A.D. and 1450 A.D., each coinciding with ice-core records of increases in stratospheric aerosols tied to major tropical volcanic eruptions, Miller said. The unexpected findings "provide tantalizing evidence that the eruptions were the trigger for the Little Ice Age," a period of Northern Hemisphere cooling that lasted from roughly 1250 to 1850, he said.

A paper on the subject was published online in Geophysical Research Letters and featured in the Jan. 28 edition of the American Geophysical Union journal highlights. Authors on the study included Miller, graduate students Rebecca Anderson and Stephen DeVogel of INSTAAR, Jason Briner of the State University of New York at Buffalo and Nathaniel Lifton of the University of Arizona.

Located just west of Greenland, the 196,000 square-mile Baffin Island is the fifth largest island in the world. Most of it lies above the Arctic Circle.

The researchers also used satellite data and aerial photos beginning in 1949 to document the shrinkage of more than 20 ice caps on the northern plateau of Baffin Island, which are up to 4 miles long, generally less than 100 yards thick and frozen to their beds. "The ice is so cold and thin that it doesn't flow, so the ancient landscape on which they formed is preserved pretty much intact," said Miller.

In addition to carbon-dating plant material from the ice edges, the researchers extracted and analyzed carbon 14 that formed inside the Baffin Island rocks as a result of ongoing cosmic radiation bombardment, revealing the amount of time the rocks have been exposed, he said. The analysis of carbon 14 in quartz crystals indicated that for several thousand years prior to the last century, there had been more ice cover on Baffin Island, Miller said.

The increase of ice extent across the Arctic in recent millennia is thought to be due in large part to decreasing summer solar radiation there as a result of a long-term, cyclic wobble in Earth's axis, said Miller. "This makes the recent ice-cap reduction on Baffin Island even more striking," he said.

Funded primarily by the National Science Foundation, the study is among the first to use radiocarbon samples from rocks for dating purposes, Miller said. The radiocarbon portion of the study was conducted at INSTAAR and the University of Arizona.

Temperatures across the Arctic have been rising substantially in recent decades as a result of the build up of greenhouse gases in Earth's atmosphere. Studies by CU-Boulder researchers in Greenland indicate temperatures on the ice sheet have climbed 7 degrees Fahrenheit since 1991.

Gifford Mller | EurekAlert!
Further information:
http://www.colorado.edu

More articles from Earth Sciences:

nachricht New Study Will Help Find the Best Locations for Thermal Power Stations in Iceland
19.01.2017 | University of Gothenburg

nachricht Water - as the underlying driver of the Earth’s carbon cycle
17.01.2017 | Max-Planck-Institut für Biogeochemie

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>