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 Massive impact crater from a kilometer-wide iron meteorite discovered in Greenland
15.11.2018 | Faculty of Science - University of Copenhagen

nachricht The unintended consequences of dams and reservoirs
14.11.2018 | Uppsala University

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Purdue cancer identity technology makes it easier to find a tumor's 'address'

16.11.2018 | Health and Medicine

Good preparation is half the digestion

16.11.2018 | Life Sciences

Microscope measures muscle weakness

16.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>