And the picture isn’t pretty.
In the last decade, two of the largest three glaciers draining that frozen landscape have lost enough ice that, if melted, could have filled Lake Erie.
The three glaciers – Helheim, Kangerdlugssuaq and Jakobshavn Isbrae – are responsible for as much as one-fifth of the ice flowing out from Greenland into the ocean.
“Jakobshavn alone drains somewhere between 15 and 20 percent of all the ice flowing outward from inland to the sea,” explained Ian Howat, an assistant professor of earth sciences at Ohio State University. His study appears in the current issue of the journal Geophysical Research Letters.
As the second largest holder of ice on the planet, and the site of hundreds of glaciers, Greenland is a natural laboratory for studying how climate change has affected these ice fields.
Researchers focus on the “mass balance” of glaciers, the rate of new ice being formed as snow falls versus the flow of ice out into the sea.
The new study suggests that, in the last decade, Jakobshavn Isbrae has lost enough ice to equal 11 years’ worth of normal snow accumulation, approximately 300 gigatons (300 billion tons) of ice.
“Kangerdlugssuaq would have to stop flowing and accumulate snowfall for seven years to regain the ice it has lost,” said Howat, also a member of the Byrd Polar Research Center at Ohio State.
Surprisingly, the researchers found that the third glacier, Helheim, had actually gained a small amount of mass over the same period. It gained approximately one-fifteenth of what Jakobshavn had lost, Howat said.
The real value of the research, however, is the confirmation that the new techniques Howat and his colleagues developed will provide scientists a more accurate idea of exactly how much ice is being lost.
“These glaciers change pretty quickly. They speed up and then slow down. There’s a pulsing in the flow of ice,” Howat said. “There’s variability, a seasonal cycle and lots of different changes in the rate that ice is flowing through these glaciers.”
Past estimates, he said, have been merely snapshots of what was going on at these glaciers in terms of mass loss. “We really need to sample them very frequently or else we won’t really know how much change has occurred.
“This new research pumps up the resolution and gives us a kind of high-definition picture of ice loss,” he said.
To get this longer-timeframe image, Howat and colleagues drew on data sets provided by at least seven orbiting satellites and airplanes, as well as other sources.
“To get a good picture of what’s going on, we need different tools and each one of these satellites plays an important role and adds more information,” Howat said.
The next step is to look at the next-largest glaciers in Greenland and work their way down through smaller and smaller ice flows.
“Currently, the missing piece is ice thickness data for all of the glaciers, but a NASA aircraft is up there getting it. When that’s available, we’ll be able to apply this technique to the entire Greenland ice sheet and get a monthly total mass balance for the last 10 years or so,” he said.
Along with Howat, Yushin Ahn, a postdoctoral fellow at Ohio State’s Byrd Polar Research Center; Ian Jouglin of the University of Washington; Michael van den Broeke and Jan Lenaerts, both of Utrecht University in the Netherlands, worked on the project.
The work is supported in part by the National Aeronautics and Space Administration and by the Climate, Water and Carbon Program at Ohio State.Contact: Ian Howat, (614) 247-8944; Howat.firstname.lastname@example.org
Ian Howat | EurekAlert!
Diving robots find Antarctic winter seas exhale surprising amounts of carbon dioxide
15.08.2018 | University of Washington
Algorithm provides early warning system for tracking groundwater contamination
14.08.2018 | DOE/Lawrence Berkeley National Laboratory
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur
What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...
08.08.2018 | Event News
27.07.2018 | Event News
25.07.2018 | Event News
15.08.2018 | Physics and Astronomy
15.08.2018 | Earth Sciences
15.08.2018 | Physics and Astronomy