Glacier-melting debate highlights importance of satellites

Feb 01, 2010
Surface velocity field for the Baltoro Glacier in Pakistan based on six Envisat Advanced Synthetic Aperture Radar images taken from 2003 to 2008. The analysis of mutli-temporal data such as these allows changes in the glacier velocity pattern to be detected accurately and quickly. Inset: Centreline velocity profile; location as depicted by dashed yellow line in main image. Note the gradual increase in flow with distance from the terminus, as is common on debris-covered glaciers, and the velocity maximum at Concordia, which is associated with the confluence of the two major tributary glaciers, the Godwin Austen Glacier and the Baltoro South Glacier. Credits: Dr Duncan Quincey, Institute of Geography and Earth Science, Aberystwyth University (UK)

The intense public debate on how rapidly the Himalayan glaciers are retreating highlights the necessity for the constant monitoring of glaciers worldwide by satellites.

Since glaciers are among the most reliable indicators of climate change and because they can have a major influence on , knowledge of the recent changes and future behaviour is of great interest for climate scientists and governing bodies. A key to assess these changes or to model their future evolution is the existence of a detailed glacier inventory.

Data from satellites allow scientists to measure glacier extent in detail, providing authoritative evidence of trends. They also allow local measurements to be expanded to a regional scale. Considering the valuable role satellites can play in determining the state of Earth's glaciers, the Global Climate Observing System (GCOS) has called for the systematic monitoring of glaciers by satellites in support of the UN Framework Convention on Climate Change.

In 2007, ESA started the GlobGlacier project as a major effort to develop and apply existing methodologies to monitor glaciers and contribute to a global glacier inventory using satellite observations. GlobGlacier, part of ESA's 'Data User Element', is adding about 20 000 of the estimated 160 000 glaciers worldwide to this inventory to allow their histories to be adequately tracked.

Kashmir, part of the Indian Himalayas, is one of the selected regions where little information is available on overall glacier extent or changes. GlobGlacier is creating inventory data for more than 1000 glaciers in this region.

The inventory combines information on glacier outlines based on archived satellite data from the Landsat Thematic Mapper (TM) and the Enhanced Thematic Mapper Plus (ETM+) instruments with topographic information from the Shuttle Radar Topography Mission and the Global Digital Elevation Model (GDEM) from ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer).

When a time series of suitable images are available for a certain region, changes in glacier length and extent can be calculated. "Such data allow scientists to assess the overall pattern of changes in a larger region for a better determination of climatic change impacts," said GlobGlacier Project Manager Frank Paul from the University of Zurich.

The above animation, based on data acquired by Landsat's TM on 15 November 1990 and by ETM+ on 1 August 2001, illustrates the changes in glacier extents that occurred during this time in the region northeast of the Gangotri Glacier, situated in Garwhal Himalaya.

While most of the smaller and debris-free glaciers show considerable retreat in this period, the larger glaciers with completely covered tongues have not changed much. Several of the pro-glacial lakes have grown. Quite a few glaciers at lower altitudes are nearly free of snow in the August 2001 image, indicating a retreat that year.

ESA's ERS-1, ERS-2 and Envisat Advanced Synthetic Aperture Radar (ASAR) data are providing velocity measurements of selected . The image to the right shows the surface velocity field for the Baltoro Glacier in Pakistan based on Envisat ASAR data from 2003 to 2008.

ESA's new Climate Change Initiative, which will produce robust long-term records of essential climate variables, will build on the results of the GlobGlacier project by further improving the algorithms for glacier monitoring and continually updating the related glacier inventory information.

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User comments : 28

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freethinking
1.7 / 5 (11) Feb 02, 2010
Oh My Word. People, if you still believe in AGW, Jim Jones has some cool-aid for you to drink, and I have a bridge to sell you.

More proof that AGW is false, how about moving weather posts, deleated source data,

http://www.guardi...er-fraud

GrayMouser
2.2 / 5 (10) Feb 02, 2010
Oh My Word. People, if you still believe in AGW, Jim Jones has some cool-aid for you to drink, and I have a bridge to sell you.

More proof that AGW is false, how about moving weather posts, deleated source data,

http://www.guardi...er-fraud

Or "The Bolivia Effect" where you create a temperature for a location by using the "nearest" station?
http://chiefio.wo...-effect/
GrayMouser
2.6 / 5 (10) Feb 02, 2010
I wonder how they calibrated their sensors once the satellites were on-orbit? Without calibration against a known reference the measurement errors would be hard to define.
freethinking
1.4 / 5 (9) Feb 03, 2010
Please dont read the following if you still believe in AGW. Please for the sake of your sanity, for the sake of you belief keep repeating, I believe in AGW, I believe in Al Gore.

http://www.guardi...r-review
JayK
2.6 / 5 (5) Feb 03, 2010
Did you guys have something useful to say about the article or are you just going on and on in your usual denier circle-jerk?
freethinking
1 / 5 (7) Feb 03, 2010
Again, leftist progressives, when shown that their arguments are deeply flawed use the following tactics. Lie, Shout down the apposing view, call names, etc. etc. They dont use facts.

So JayK since you resorted to name calling you are a leftist progressive.

If you have facts that prove AGW, lets have it. Just have the source data, source code, or any real science to backup your claim read.
JayK
4 / 5 (4) Feb 03, 2010
So the answer to my question is no, you have nothing to comment about this article, you're just here to validate your own personal viewpoint.

Thanks for the straightforward answer, but I think the actual comments section are for those that would like to discuss the article in question.
Skeptic_Heretic
2.7 / 5 (3) Feb 04, 2010
One need only watch how you rank others to determine whether you're interested in conversation, JayK.

As for the article above, I agree that satellite monitoring is a very important aspect in determining the truth of climate change. We should bring any and all tools available into the discussion to create the data needed to objectively look at the situation. That is the methodology of science.
freethinking
1 / 5 (6) Feb 04, 2010
jayK,

I did have something useful to say. AGW is bunk and it is proven bunk. I have given links, and many other people have given facts. But for AGW believers, facts don't matter.

I asked you to show me where your facts are? Waiting.....

How about this since you have no facts, what facts would convince you that AGW is a fraud? I asked another AGW believer and he was straight forward, he said nothing could convice him.

What would convice me that AGW existed? Facts. Unfortunately facts and science does not exist on the AGW side. Name calling, lying, deception, persecution, shouting, rating as 1, does not count as facts.
JayK
2.6 / 5 (5) Feb 04, 2010
Skeptic, I have absolutely nothing to say either way. I find that the Dunning-Kruger effect is high in these threads. I also was wondering why people such as yourself and the misnamed "freethinking" waste your time here if all you are going to do is participate in a virtual "circle-jerk" of self-confirmation, much like a mob mentality.

As for freethinking, my facts are spread out everywhere. The raw data itself is all available, and the conclusions of experts is far more than anything you have ever offered. Your previous link to the guardian was so emotionally charged and limited in fact that it clearly explains your need for validation of your opinion.
Skeptic_Heretic
2 / 5 (4) Feb 04, 2010
I also was wondering why people such as yourself waste your time here if all you are going to do is participate in a virtual "circle-jerk" of self-confirmation, much like a mob mentality.

Would you like to point out where I've done that or are you content to troll commentary with adhominem attacks?
freethinking
1 / 5 (6) Feb 04, 2010
JayK,

There are many different points of view here. I call myself freethinker as I am not vested on any point and if the facts show I'm wrong I change my views.

Facts are spread out everywhere, true. Fact are polar bears are not drowning, and their population is increasing.
Fact is source data for AGW Has been deleted.
Fact is Al Gore and AGW proponents are making a fortune on AGW.
Fact is AGW scientists will not release their models program code.
Fact is AGW scientists knew they had bad information and decided to keep it for the express purpose of misleading world leaders.
Fact is AGW scientist would be charged with crimes if the statute of limitations didnt expire.
Fact is AGW models are wrong.
Fact is AGW scientist purposely tried to prevent those with opossing views from publishing their data.
Fact is many Glaciers are growing.
Fact is many temperature stations have moved, been shown inacurate, making their data invalid.

Your facts please?
Skeptic_Heretic
1.5 / 5 (2) Feb 05, 2010
JayK,

You reference the Dunning-Kruger effect. Praytell, what are your credentials that you can speak on these subjects with authority? Could you not be suffering from the same?
rubberman
3.5 / 5 (6) Feb 05, 2010
Nice climate debate.....
The value of satelite monitored changes in glacial conditions is invaluable, regardless of the causes of the changes. If my water supply was glacial meltwater I would definitly feel better knowing that it was being tracked...
Caliban
2.3 / 5 (3) Feb 06, 2010
Rubberman- thanks for having something to say that relates directly to the content of the article.
JayK-glad someone is still fighting the good fight. These denier, circle-jerk clowns don't have anything at all to add to the debate over the reality of climate change, much less the validity of the anthroprogenic hypothesis. The goal on their part at this point is obviously to turn up the noise level and try to overwhelm/aggravate anyone interested in trying to learn more about this topic or make intelligent comment on it. With regard to "freethinking" and "skeptic heretic" they are literal oxymorons, who have taken to the trollpuppet practice of cutting and pasting large segments of their posts, and making cut-paste, blanket, preemptive posts to almost any articles here on physorg relating directly or indirectly to climate change. Paid shills? Possibly. Trollpuppets? Definitely.
Caliban
2 / 5 (4) Feb 06, 2010
Correction. skeptic hasn't yet fallen to the level of cut and paste. My apologies. Knee-jerk denier, yes. Cut and paste, no.
freethinking
1 / 5 (4) Feb 06, 2010
Where is the facts?
Caliban, JayK, I ask again, please show me the science that shows AGW is real? Saying something is real, shouting down others who say it isn't doesnt prove your point.
Right now, please show me the evidence that has not been tainted by shoddy science, moved weather stations, lies, deception, deleted source data, bad models, corrupt scientists?

Waiting.... still waiting....
Caliban
1 / 5 (2) Feb 06, 2010
Stay the course there, freethinking. Shouldn't cause you any difficulty, as it is obviously the only course you are capable of following.
thermodynamics
5 / 5 (1) Feb 07, 2010
OK, I'll bite. Freethinker listed a number of "facts" that he thinks debunk AGW. I'll just pick one to talk about and then I hope he will remove it from his list (although I am pretty sure he won't). He talks about the polar bear increase in population. That is absolutely correct but also disingenuous. I know he has to be smarter than to not understand the numbers. First, recognize that there were only rough estimates on polar bear numbers 60 years ago. Also, the numbers are not precisely known now. Let me give you the numbers: 5000 estimated in the 1950s. 20,000 - 25,000 in 2005. However, what is not said is that the bears had been hunted to near extinction in the 1950 by humans. There was an international treaty to save them. The treaty has been successful, but they are still a small population on the brink of extinction and studies show that they depend on the ice. IF (and I use that word to say I don't know) the ice melts, they are toast. One simple example.
freethinking
1 / 5 (4) Feb 07, 2010
Polar Bears are just one example. If we spend billions on top of billions of dollars on a non-existent problem, there will be no money left to save the Bears.

5000 in 1950, 25000 in 2005 the population is going in the right direction.

Polar bears survived warmer temperatures in the past, in the future when the climate changes (due to natural course of events) they will survive, as long as man has the inclination to save them. If humans are forced to hunt them because environmentalists sent everyone back to the stone age, they will become extinct.

AGW belief has now become like the belief in UFO's. UFO believers are asking people to believe in UFO based on junk science and ask those who doubt to prove them wrong.
Skeptic_Heretic
not rated yet Feb 08, 2010
Correction. skeptic hasn't yet fallen to the level of cut and paste. My apologies. Knee-jerk denier, yes. Cut and paste, no.


Excuse me? How am I a knee jerk denier? I don't know what the truth of the issue is, realistically no one does. I think you need to take a step back and rethink your stance.
Caliban
1 / 5 (1) Feb 08, 2010
Skeptic-
My apologies. You did nothing to deserve that criticism.
I agree with you that the exact truth may be a little evasive, but in this case, with so much- in fact, everything- at stake, we need to err on the side of caution and take immediate steps to eliminate greenhouse gas emissions. It is way past time for us to have completely replaced fossil fuels as an energy source. They are unsustainable, destabilizing, and damaging. And this is what is at the heart of the debate, whether stated or unstated. Just so happens that pretty much all the science supports the proposition, even with some admitted flaws and/or manipulation.
frenchie
1 / 5 (3) Feb 08, 2010
I just have to address some of that nonsense posted by "freethinker."

Facts are spread out everywhere, true. Fact are polar bears are not drowning, and their population is increasing.
-As pointed previously, population increase is due to non-hunting activity and has no affect on proven drowning due to habitat loss/excessive swimming.

Fact is source data for AGW Has been deleted.
-Unproven if not disproven alltogether. In fact you're looking at source data in this article.

Fact is Al Gore and AGW proponents are making a fortune on AGW.
-So does big oil off continuing buisness as usual practices of a fossil fuel economy. As for scientists in the field, much like their counterparts in other RESEARCH fields, the salaries are well below private enterprise.

frenchie
1 / 5 (3) Feb 08, 2010
Fact is AGW scientists will not release their models program code.
- A scientist who has worked for years on ANY matter can hardly be asked to give his work again before publishing a paper nor after. If you find that unacceptable, i would suggest you offer money for said code.

Fact is AGW scientists knew they had bad information and decided to keep it for the express purpose of misleading world leaders.
-That's a fantasy denialists wish were true and tout loud and hard. Maybe you're refering to the tricks used to create graphs. Well I use tricks everyday to achieve my models. To tell the truth 3.1416 works great as a quick trick to calculating anything involving PI. as for c, 3e8 works too.

Fact is AGW scientist would be charged with crimes if the statute of limitations didnt expire.
Fact is AGW models are wrong.
- And your infinite knowledge of article reading has allowed you to say this over decade long researchers how exactly?
frenchie
1 / 5 (3) Feb 08, 2010
Fact is AGW scientist purposely tried to prevent those with opossing views from publishing their data.
-You may have a point there although I haven't looked into it. Thus my lack of knowledge precludes me from saying otherwize. Regardless if true, said scientists would be better served by disproving rather than opposing the papers.

Fact is many Glaciers are growing.
- Yeap during winter glaciers grow, during summer they receed...overall, Glaciers are disappearing. Look at some of the ice shelves in Antartica. Kilimanjaro is nearly free of its perma ice cap of fabled pictures. yet a more disturbing look is the increasing disappearance of chilean glaciers which are the primary source of fresh water in its region. The list goes on.

Fact is many temperature stations have moved, been shown inacurate, making their data invalid.
- No ideas on this.

It says here that brevity is the soul of wit. Such 1 line attention grabbers also seems to be the bane of rational thinking.
Skeptic_Heretic
not rated yet Feb 09, 2010
I agree with you that the exact truth may be a little evasive, but in this case, with so much- in fact, everything- at stake, we need to err on the side of caution
True caution would be adhering to our current non-pollution initiatives and determining the truth of the situation before we act. Without a direction to move in we're just stumbling through the wilderness, and there are many a thing that we don't know about in this equation. I'd rather sit back and take my time to determine how best to address a problem, than run head long into the problem and exacerbate the situation.

It is way past time for us to have completely replaced fossil fuels as an energy source.
Well no kidding. We should have briefcase thorium nuclear reactors that we can plug into our houses and have power for our vehicles and anything else we'd use by now.
GrayMouser
1 / 5 (3) Feb 09, 2010
Did you guys have something useful to say about the article or are you just going on and on in your usual denier circle-jerk?

you mean asking how they calibrate the satellites isn't useful? I would have thought it was critical.
frenchie
1 / 5 (2) Feb 10, 2010
a calibration implies a comparison over a known standard. In LEO satellite in question it is a "Advanced Spaceborne Thermal Emission and Reflection Radiometer." The key here is 2 fold, Thermal Emission and reflection Radiometer. I'm no expert in thermal so i'll focus on the radiometer.
I would assume that the calibration is done by taking measurements over a known area, with known distance, absorbion rate and reflective index. This measurement overs a baseline which can be removed from direct data as noise is.

Example: a measurement is taken over a 0 altitude (with respect to sea level) at a given longitude and latitude with known rock composition for absorbtion. the measurement is repeated at xxx altitude. the difference gives you the loss of that altitude difference assuming similar rock / soil composition. Rinse and repeat.

Maybe my details are 100% spot on but that's the general idea of it and calibrations in general.