Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NASA Scientist Claims Warmer Ocean Waters Reducing Ice Worldwide

27.03.2006


Jakobshavn Glacier Retreat 2001-2003: Jakobshavn Isbrae holds the record as Greenland’s fastest moving glacier and major contributor to the mass balance of the continental ice sheet. Starting in late 2000, following a period of slowing down in the mid 1990s, the glacier showed significant acceleration and nearly doubled its discharge of ice. The following image from the Landsat satellite shows the retreat of Jakobshavn’s calving front from 2001 to 2003. Credit: NASA


Glaciers and ice sheets around the world have a big problem: warmer waters.

According to a NASA scientist, the pieces to a years-old scientific puzzle have come together to confirm warmer water temperatures are creeping into the Earth’s colder areas. Those warm waters are increasing melting and accelerating ice flow in polar areas.

This conclusion appears in an article by Robert Bindschadler, a glaciologist at NASA’s Goddard Space Flight Center in Greenbelt, Md. His article is in the March 24 issue of Science magazine.



Temperatures collected from ships and buoys showed a warming of all oceans. That increase began before satellite sensors detected temperature increases of sea surfaces. Most of the warming was limited to the oceans’ upper 1000 meters (.62 mile), except in the North Atlantic. In the cold North Atlantic waters, heat penetrated even deeper. This warming has increased the melting of sea ice in the North Atlantic. Overall ocean heat content changes are monitored by ocean altimetry missions like TOPEX and Jason-1 and the on site Argo buoy network floats that broadcast measurements to a satellite. These provide information on ocean temperatures.

It has another effect, however, which may potentially be of great significance to sea level rise, and that is that these warm waters are beginning to melt the underside of the floating fringes of the Greenland ice sheet, even at great depths, It is these fringes that have been holding back vast stores of ice locked up in the Greenland ice sheet, and as this ice has been melting, the glaciers have hastened their flow to the sea.

A recent assessment in the changes in speed and the amount of snow and ice around Greenland confirms a large melting of outflow glaciers and acceleration of ice flow. Three large glaciers, the Kangerdlugssuaq, Helheim and Jakobshavns Isbrae have been melting at a rapid rate over the past several years. Jakobshavns, the largest outlet glacier on Greenland’s east coast, has been annually thinning at 15 meters (49.2 feet) since 1997. The other two glaciers have also been thinning. Kangerdlugssuaq at 40 meters (131.2 feet) per year and Helheim at 25 meters per year (82.0 feet), which can’t be explained by normal melting. All of these glaciers have also been accelerating. This isn’t just happening in Greenland, scientists are seeing similar behavior in Antarctica as well.

"Deep outlet glaciers around both major ice sheets are accelerating and thinning means warm water has reached them," Bindschadler said. "I see no process to reverse this and expect increased ice sheet discharge to continue and probably to spread with the result being further accelerations to sea level rise."

"Understanding just how significant these rapid losses are to the overall ice sheet balance requires a comprehensive look at melt, accumulation and flow characteristics over the entire ice sheet," said Waleed Abdalati, head of the Cryospheric Sciences Branch at Goddard. "Various satellite and aircraft observations are providing this critical information and are shaping our understanding of Greenland’s behavior. The story is still unfolding, but the dramatic changes at the margins are quite striking."

The evidence is clear to Bindschadler that increased snowfall predicted in a warmer climate can’t possibly keep up.

While it is true that the piece is opinion, it fits previously disconnected pieces of the climate and ice puzzle together and attempts to draw conclusions. The conclusions cannot be verified without new measurements, and NASA is compiling them with satellites like ICESat. ICESat enables scientists to precisely measure changes in the elevation of ice and snow on glaciers and ice sheets as they respond to a changing climate.

In an effort to understand these changes, NASA continues to monitor sea surface temperatures; and, the behavior of glaciers and ice sheets around the world.

Bindschadler said as sea ice diminishes over time in the Arctic and parts of the Antarctic, warmer waters in polar areas will come closer to the surface. They will reach shallower tidewater glaciers, and increase melting at their bases triggering additional ice flow into the oceans. Over time, the warmer waters also will move northward along Greenland’s coasts initiating acceleration and thinning of additional glaciers, leading to additional sea level rise.

Rob Gutro | EurekAlert!
Further information:
http://www.nasa.gov
http://www.nasa.gov/centers/goddard/news/topstory/2006/ice_puzzle.html

More articles from Earth Sciences:

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

nachricht Modeling magma to find copper
13.01.2017 | Université de Genève

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

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...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

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

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

127 at one blow...

18.01.2017 | Life Sciences

Brain-Computer Interface: What if computers could intuitively understand us

18.01.2017 | Information Technology

How gut bacteria can make us ill

18.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>