A NEW approach to measuring glacier behaviour can keep track of the rapidly changing erosion of ice in south-east Greenland.
Earlier studies focused on two large, rapidly thinning glaciers, but these actually contribute relatively little to total ice loss. Satellite measurements of the island's gravitational field imply a much greater loss than the large glaciers alone can account for.
Now a team led by Ted Scambos of the University of Colorado in Boulder has resolved the disparity by looking at a wider range of glaciers. They used laser altimetry to measure the thinning of inland ice, plus satellite images that show changes at the margins of the ice sheet. Overall, they found that the region is losing more than 100 cubic kilometres of ice a year.
- From issue 2668 of New Scientist magazine, page 16. Subscribe and get 4 free issues.
- Browse past issues of New Scientist magazine
If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.
Have your say
Weight Of The Ice
Sat Aug 09 13:22:25 BST 2008 by Andrew
Has anyone considered the consequences of the redistribution of the weight of the ice across the broader water masses? Presumably Greenalnd is getting lighter as the ice melts and rising? Is anything else going to 'pop' as a result of this?
Weight Of The Ice
Sat Aug 09 14:44:36 BST 2008 by Richard Owen
Also consider this:
The variables are such, that we will never fully understand anything....
They are also the reason why weather
forecasting and computer modelling/simulation
are so inaccurate. R.Owen 05/08/08
Weight Of The Ice
Mon Aug 11 11:24:59 BST 2008 by Craig
Weather forecasting has improved drastically over the last 2 decades and is reasonably accurate.
Weight Of The Ice
Sat Aug 09 14:51:30 BST 2008 by Dr Ray Wills
Yes indeed - the technical phrase you need is isostatic post-glacial rebound - the response of the land mass is slower than the loss of the ice - a lot of information on line.
Weight Of The Ice
Sun Aug 10 11:44:30 BST 2008 by Andrew
So one side of the North American plate is going to have a lot of ice melt and so get lighter, and rise. Now the other side of the North American plate is around the San Andreas fault (?). So is this increasing the likelihood of a big quake along this fault?
Weight Of The Ice
Sun Aug 10 17:02:19 BST 2008 by Bud
I live in Albuquerque, New Mexico the elevation is 5000 ft. Ever since I was a kid we would go fossil hunting in the Sandia Mountains which are about 10,000 ft above sea level. Most prolific are sea shells. Yes, sea shells in the middle of the high dessert. This planet has been here a long, long time and has seen incredible geographical and climatic changes. What I don't understand with the enviromaniac is why do they think that our planet should all of sudden stop having these changes? My suspicion is they are afraid of the unknown. This is understandable but unrealistic. We need to be concerned about clean water and air but we can't panic or big mistakes will be made under false assumptions. Panic never solves any problem.
The improvements we've made over the last 30 or 40 years in cleaning up our water and air is substantial. New methods and technology are not linear they are exponential. The rate at which we are making improvements in cleaner air and water are increasing very quickly but we are not there yet. It would be a huge mistake to make a huge plunge into solar or wind right now. We would literally have to blanket the country in solar cells and wind turbines in order to replace our current energy needs. How are environmentalists going to feel about energy companies tearing up billions of acres to install these solar and wind farms? Imagine the huge battery farms we'll need to store all of this energy.
Currently there are scientists working on major innovations in solar collection that could actually make solar a feasible alternative to oil but itââ¬â¢s not ready now. What we have available right now is nuclear energy. If we could cut all the government red tape and stop the environmentalists from filing lawsuits to stop the development we could have several Nuclear power plants up and running in 5 years. We are on the brink of a feasible electric automobile. We are approaching the time when hydrogen can be produced efficiently. Things are happening but we can't panic and jump on the closest band wagon because it's politically correct for some.
We need to take a deep breath and make the right decisions. The world isn't coming to end any time soon. Think about where we've been and were we are now. Humans always move in a positive direction. Ever since we've been on this planet we've innovated and improved our environment. It's not going to stop now.
.
Weight Of The Ice
Mon Aug 11 07:10:49 BST 2008 by Stew
No one questions the fact that environmental change is inevitable, and actually a requirement for a healthy planet. The problem at hand is the rate of the change. A 150 000 years as opposed to a 150 years is significant I would wager.
The world may not end but at this rate it will become uninhabitable for the likes of you and me within a few generations.
Humans move in a positive direction? How do you call pollution positive? I think it is in the wrong direction and we are only now trying to reverse. We *try* to move in the right direction but sometimes we don't due to ignorance and lack of education. Unfortunately this time we don't have the luxury of time required to turn around this huge inertial mass that is the majority of human population.
We don't need to blanket the countryside with solar panels at all.
http://abc.com.au/rn/scienceshow/stories/2008/2303970.htm
Just read the transcript or listen to the dialog before dismissing solar energy.
And I am not an advocate for any one type of energy, I beleive it will be a combination of many sources. Fusion (if it ever works) would be interesting as is solar, wind and tidal. Clean in that there is far far less waste than nuclear or coal.
Cheers.
Weight Of The Ice
Tue Aug 12 04:35:33 BST 2008 by Bud
Stew,
I'm feel bad for you because you see the world and humanity in such a negatice way. This planet and the people on it are awesome and beautiful. Stop and look around you - look at the sky, look at the people around you. It's miraculous! We are so fortunate to live in this place. Enjoy it! Everything is gong to be okay. We will find the right solution to the problem of dirty air and water. Have faith in your fellow man.
Weight Of The Ice
Mon Aug 11 12:00:21 BST 2008 by Paul
Another 5 nuclear power plants would be great!
Imagine the gas saved. It may even be enough for the average american to upgrade their F150 truck for a hummer.
Keep on truckin!
Weight Of The Ice
Tue Aug 12 20:52:48 BST 2008 by Andyl
I had planned to give you a long winded reply, but all I can say or ask is.... Improved for whom? By what moral compass do you ascertain this value statement. We have surely wrought much change, to the benefit of some, and to the equal and opposite detriment of more, whether our species or some unfortunate other. I am not a pie eyed naive.. I know change and death happen, but if we have made these improvements, how exactly to you measure them. Prove your f'in point. And don't cheat. Don't say its obvious. Is it obvious to all humans, or must they wait their turn? Is it obvious to all species, or are they transiencies in our march towards the better. Give me a break. You clearly think us, the concerned, are naive and stupid and don't think it through, or for that matter love our fellow man the way you do. We do think it though, reason, and debate, and are ready to change our views. It is not impossible that you are in for a surprise when your "improved" position is assaulted. Good luck with that.
Weight Of The Ice
Mon Aug 11 12:16:12 BST 2008 by Jacques Bogaarts
People in the Baltic region know from experience that the land level is still rising as a result of the melting of the ice after the last ice age. Old people living on the Swedish coast remember places that were flooded by the Baltic when the were young and now are dry land.
Weight Of The Ice
Mon Aug 11 23:49:11 BST 2008 by Blue7053
Andrew,
The weight of the 'polar ice' will be transmuted into 'equatorial water'. The ultimate effect will be a transferance of polar squeeze into a gravitational equatorial squeeze.
Result? Probably earthquakes and volcanos.
Ahhum
Sat Aug 09 15:19:02 BST 2008 by Gregory
Oh you have to be so gullible to believe in global warming, the queen is just trying to take control of the world by trying kill africa off... Cough
Ahhum
Sat Aug 09 15:37:57 BST 2008 by Vendicar Decarian
"Oh you have to be so gullible to believe in global warming,queen is just trying to take control of the world by trying kill africa off... Cough "
No.. No.. The Queen is far too busy heading the Illuminati and dealing drugs to raise the money to establish a global communist government run for Lucifer.. Just ask Lyndon Larouche and his American Conservative followers.
Ahhum
Sun Aug 10 14:20:41 BST 2008 by Sophia
It is no longer a question of "beleiving in" global warming, the fact is we don't know what the hell is going on in the climate, whats natural, what isn't, and how these thousand of interconnections between the earth/atmosphere/ocean system connect. Recent ice core, lake sediment and ocean sediment records reveal the climate oscillations of the past but there is so much more to go - this is only the tip of the iceberg - as it were.
Dont know where you're reference to the queen came from? She prob doesn't even know how the climate works and what it would do to africa.
Global Warming
Sat Aug 09 17:17:10 BST 2008 by Keith
If we didn't destroy the world we live in then the ice would not have melted. Leaving the ice sheet heavier, were gravity would have no effect due to the weight of the ice. Of course global warming isn't the reason though, so lets test a few more nukes, keep pumping carcenagins in the air, drop more bombs all over the world, an accelerate it even more. Then when we all live on boats i can say i told you so.
Global Warming
Sat Aug 09 23:37:23 BST 2008 by Jerome
Soooo ... I wonder what caused the demise of the humongous glaciers which covered half of north america 10,000 years ago. Oh, I know. The world got warmer because of those pesky mammoth and yak farts.
Global Warming
Sun Aug 10 16:12:47 BST 2008 by Vladimir
...and that happen in only 100-200 years. Wright?
Global Warming
Sun Aug 10 18:08:12 BST 2008 by Coolgeo56
Actually, it was 13,200 years before present and, yes, it probably happened in a couple of decades. Recent studies by the University of Nevada, Reno indicate that Lake Lahonton, one of the basins in the western US that got filled by the glacial melt, filled very rapidly. Sediment cores and shorelines elevations clearly show a rapid progression.
Another example was the rapid rise in Lake Bonnieville's elevation at that same time. The date of the catastrophic Colombia River floods all suggest a time in the same neighborhood. That flood was caused by the overfilling of the NV-UT basins, however, one basin it filled had an exit to the ocean and the gap by which it flowed through is now called Red Rock Canyon.
Probably equally interesting has been the wild climatic fluctuations since 13ka, three moderate ones and several little ones. The last was a brief cold period that ended in the early 1800s. Remember the very cold winters and cold summers that drove the potato famine? Well, we have been climbing out of the cold spell ever since.
Now it just so happens that it also corresponds to the rapid rise in CO2 and increased industrialization. While increased CO2 has been seen to occur with increased global temperatures in the past, it is not clear if it is the chicken of the egg - that is was it the cause or the consequence? That is the big question, and as Gore points out, we better not be wrong on that one.
As good scientists, we all should understand the facts rather than jump to conclusions pointed out by those less knowledgeable, and those people should learn to rely on us more often.
In my opinion, "global warming" is happening, but what is the real cause? Whether nature or man-made, or some combination thereof, I think it is better described as "global pollution". That is the better phrase, and by god, we have done that quite well.
All comments should respect the New Scientist House Rules. If you think a particular comment breaks these rules then please use the "Report" link in that comment to report it to us.
If you are having a technical problem posting a comment, please contact technical support.
PRINT
SEND
