Feeds

Satellite shows Greenland's ice sheets getting thicker

All down to more snow falling, it seems

Top 5 reasons to deploy VMware with Tegile

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. ®

Beginner's guide to SSL certificates

More from The Register

next story
LIFE, JIM? Comet probot lander found 'ORGANICS' on far-off iceball
That's it for God, then – if Comet 67P has got complex molecules
Rosetta probot drilling DENIED: Philae has its 'LEG in the AIR'
NOT best position for scientific fulfillment
'Yes, yes... YES!' Philae lands on COMET 67P
Plucky probot aces landing on high-speed space rock - emotional scenes in Darmstadt
HUMAN DNA 'will be FOUND ON MOON' – rocking boffin Brian Cox
Crowdfund plan to stimulate Blighty's space programme
THERE it is! Philae comet lander FOUND in EXISTING Rosetta PICS
Crumb? Pixel? ALIEN? Better, it's a comet-catcher!
SEX BEAST SEALS may be egging each other on to ATTACK PENGUINS
Boffin: 'I think the behaviour is increasing in frequency'
Post-pub nosh neckfiller: The MIGHTY Scotch egg
Off to the boozer? This delicacy might help mitigate the effects
I'M SO SORRY, sobs Rosetta Brit boffin in 'sexist' sexy shirt storm
'He is just being himself' says proud mum of larger-than-life physicist
prev story

Whitepapers

Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Choosing a cloud hosting partner with confidence
Download Choosing a Cloud Hosting Provider with Confidence to learn more about cloud computing - the new opportunities and new security challenges.
New hybrid storage solutions
Tackling data challenges through emerging hybrid storage solutions that enable optimum database performance whilst managing costs and increasingly large data stores.