New measurements show that the flow of ice in the Greenland ice sheet has been accelerating since 1996 during the summer melt season. The results suggest that the ice sheet may be responding more quickly to the warming climate than previously thought.
In an article published in Science magazines online Sciencexpress June 7, Jay Zwally, an ICESat Project scientist at the NASA Goddard Space Flight Center, Greenbelt, Md., Waleed Abdalati, a Polar Program scientist at NASA Headquarters, Washington, and colleagues report that increases in ice velocity during the summer are correlated with the timing and the intensity of ice sheet surface melting.
Using periodic Global Positioning Satellite measurements from 1996 through 1999, the researchers discovered that the ice flow speeds up from 31.3 cm (12.3 inches) per day in winter to a peak of 40 cm (15.7 inches) per day in the summer when surface melting is largest. "This study demonstrates that surface meltwater travels quickly through the 1200 meter (approx. 3/4 mile) thick ice to the bedrock to make the ice slide faster. This process was known for decades to enhance the flow of small mountain glaciers, but was not known to occur in the large ice sheets," Zwally said.
Rob Gutro | EurekAlert
New research calculates capacity of North American forests to sequester carbon
16.07.2018 | University of California - Santa Cruz
Scientists discover Earth's youngest banded iron formation in western China
12.07.2018 | University of Alberta
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
16.07.2018 | Physics and Astronomy
16.07.2018 | Life Sciences
16.07.2018 | Earth Sciences