Feeds

Satellite shows Greenland's ice sheets getting thicker

All down to more snow falling, it seems

Next gen security for virtualised datacentres

While the edges of the glaciers are melting, the ice sheets in Greenland's interior are getting thicker, according to satellite data collected over the last 11 years. On average the ice sheets have got thicker by about six centimetres each year, the researchers say.

The researchers, based at Norway's Nansen Environmental and Remote Sensing Center (NERSC), say that this is probably because snowfall in the region has increased, due to a weather pattern known as the North Atlantic Oscillation (NAO).

The research was conducted using the European Space Agency's ERS satellites. These carry radar altimeters that send 1800 radar pulses to Earth each second, and record how long they take to return to the satellite. The sensor can time this journey down to the nanosecond, ESA says, meaning that the instrument is accurate to within two centimetres.

In total tens of millions of data points were collected. The results were then compared to the known fluctuations in the NAO over the period. The researchers found a strong relationship between changes in the height of the ice sheet and the strong positive and negative phases of the NAO.

Professor Ola Johannessen of NERSC says that the results suggest that the role of the NAO in ice thickness is more significant than previously thought, making it something of a wildcard in climate modelling.

"There is clearly a need for continued monitoring using new satellite altimeters and other observations, together with numerical models to calculate the Greenland Ice Sheet mass budget," Johannessen commented.

It is just the kind of work that the CryoSat mission would have taken on, had it not been lost during its launch.

The NAO was first identified in the 1920's, and is an imbalance in atmospheric masses between the high pressure of the subtropicals the low pressure of the northern polar regions. The size of the difference influences the weather across the whole of the northern hemisphere, and is much more important in the winter months.

Finding out whether or not the Greenland ice sheet is shrinking overall is important because it is so large. While plenty of data has been collected on the retreating glaciers and thinning edges of the ice sheets, much less in known about the interior.

If the Greenland ice sheet were to melt entirely, it would raise global sea levels by seven metres. The addition of such a large quantity of fresh water to the oceans would also disrupt familiar ocean currents, such as the gulf stream, which could have a huge knock on effect on weather systems.

The research was published in Science Express late last month. ®

Secure remote control for conventional and virtual desktops

More from The Register

next story
Our LOHAN spaceplane ballocket Kickstarter climbs through £8000
Through 25 per cent but more is needed: Get your UNIQUE rewards!
LOHAN tunes into ultra long range radio
And verily, Vultures shall speak status unto distant receivers
NASA to reformat Opportunity rover's memory from 125 million miles away
Interplanetary admins will back up data and get to work
SpaceX prototype rocket EXPLODES over Texas. 'Tricky' biz, says Elon Musk
No injuries or near injuries. Flight stayed in designated area
EOS, Lockheed to track space junk from Oz
WA facility gets laser-eyes out of the fog
Volcanic eruption in Iceland triggers CODE RED aviation warning
Lava-spitting Bárðarbunga prompts action from Met Office
LOHAN Kickstarter push breaks TWELVE THOUSAND POUNDS
That's right, folks, you've stumped up OVER 9,000 beer tokens - and counting
prev story

Whitepapers

Endpoint data privacy in the cloud is easier than you think
Innovations in encryption and storage resolve issues of data privacy and key requirements for companies to look for in a solution.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Advanced data protection for your virtualized environments
Find a natural fit for optimizing protection for the often resource-constrained data protection process found in virtual environments.
Boost IT visibility and business value
How building a great service catalog relieves pressure points and demonstrates the value of IT service management.
Next gen security for virtualised datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.