Brett, the IPCC AR4 WG1 report explicitly states that it had to exclude possible sea level rise due to these effects since there wasn't (and still isn't) a scientific basis for estimating how fast the melt could proceed. Coming up with such an estimate is a complex exercise that involves modeling both ice sheets in detail, and while the glaciologists are working hard on the problem it may be another five years or so before we start seeing the results of that work.

The key point is that it is now uncontroversial among glacologists that the effects of this "dynamical" melting will be substantial. See this paper for a discussion of the situation (I think from about a year ago, but there's nothing more recent with this kind of detail). Note that just a few years ago there was more or less a consensus that the 2001 IPCC assessment that the ice sheets would accumulate mass as warming progressed during the 21st century was still correct, so the field has been a little whipsawed.

Jim Hansen observes (start with this recent note, but see this linked paper for the specific discussion of this point) that under natural conditions this type of rapid ice sheet melting (of the sort seen at the end of glacial periods) is paced by high-latitude insolation increases due to orbital (Milankovitch) changes. These changes are quick in geological terms but slow on a human scale. While on the one hand there is less ice to be melted now than during a natural deglaciation, on the other hand there is no natural "speed limit" of the sort mentioned above.

Old news. From a 2002 article, Further, they suggest that the observed process may also have contributed to the extensive melting of the Greenland Ice Sheet during the last Interglacial period, some 125,000 years ago. According to the U.S. Geological Survey, previous studies have shown that during the last Interglacial period, carbon dioxide (CO2) concentrations in the atmosphere were relatively high, temperatures may have been higher than the present, and sea level may have been approximately 6 meters (19.5 feet) higher. "During this time when the climate was warmer, the ice sheet was less extensive.

What the heck is going on here? This can't be. The present warming is unprecedented, yet this article expects us to believe that CO2 concentrations were high, temperatures higher than present, and sea level 6 meters higher than today.

Was this natural or due to AGW? Everyone knows that any warming can only be attributed to AGW, but what I want to know is how our ancestors managed to pull this off. Alien help?

Obviously, the moulins hate our coastlines for their freedom.

As a non expert in this field but with a very keen interest, i am worried about where all of this fresh water from melting ice in the Arctic is going! Will these large quantities of meltwater effect the thermohaline as has been theorised and mentioned on earlier entries on this site. Whether your a sceptic or not,this must be worrying, wasn't it large amounts of fresh water pouring into the North Atlantic that caused the Younger Dryas at the end of the last glacial?

um, why is it so difficult to grasp the credibility of the connection between extracting and releasing massive amounts of carbon based energy into the atmosphere and rising global temperatures? CO2 concentrations are accelerating NOW, and it's largely due to human influence...there is hardly any lack of consensus on this process.

what's with this argumentative stance that there needs to be absolute certainly on the source of global temperature rise, melting glaciers, etc. before we take proactive measures to protect our future viability?

is it so the "progressives", "liberals", and "Al Gore" types can be proven wrong?

what position or interests are you defending by arguing and suggesting that we do nothing?

Brett,

The article written by Paul Brown of AlterNet is written with all the fervor of a true believer, complete with the looming apocalypse and the seemingly mandatory belittling of all who dare to disagree. For you to say that AlterNet is a "progressive" newsite is exceedingly kind on your part. It is a blatantly in-your-face leftwing rag. You should try to make your postings at least somewhat science-oriented, and from somewhat more neutral sources.

Steve

Reply: Steve, I try, but there are times when it cannot be avoided either way (right or left) in order to get the story.

Paul,

The key word in the link is relatively high.

Over the last 650,000 years, CO2 levels have been found to vary naturally between 180 to 280 ppm.

180 ppm during ice ages.

280 ppm during warm periods.

Current CO2 levels are elevated at about 385ppm.

This provides a warming of the atmopshere and allows it to hold more water vapor (another greenhouse gas).

So, the net result is much greater warming now than before.

Is this amount of melting likely to slow the gulf stream further?

Yep, people started noticing this effect about five years ago. In the intervening period it's gotten a lot more noticable.

Paul, nobody thinks you're that stupid, nor is your rhetorical flopping around going to convince anyone. All you're doing is embarassing yourself.

But just in case you really are confused:

Wait for a warm day and put an ice cube outside in a sunny location. Observe that the ice cube melted due to natural influences.

Take another ice cube and put it in the same location. Let it begin to melt, but then take a good-sized magnifying glass and focus it on the ice cube. Observe that the ice cube melted faster due to the combination of natural and anthropogenic influences.

There you go.

My underwater suspension Tunnel idea prevents this also.

Greenland ice cap melting faster than expected

COPENHAGEN, Oct 11 (AFP) Oct 11, 2007
The ice cap in the northern hemisphere is melting a lot more rapidly that scientists thought, according to new research published Thursday by the Danish National Space Center.

http://www.terradaily.com/2007/071011171235.27npmcyt.html

More Global Warming craziness! How about the arctic, indian (maldives), pacific (tavalu)sea levels are falling! The interior Antarctic Ice sheets are reaching records thicknesses, Scottish mountains just recieved snow a month earlier than normal, there's been significant snow fall in the Alps, we've had record lows in 7 states since the beginning of October, we've had very low hurrican activity, Alaskan glaciers have advanced 1/3 of a mile in less than a year, the glaciers in France and Switzerland are growing, Mount St. Helen's glacier is growing rapidly, ok, I quit...this must be all attributable to global warming...

Brett,

I know that you are an expert on Canadian weather. I've been noticing that it's been quite warm in mainland nunavut over the past couple of days. Is there a simple explanation for their current warm pattern. I plan on watching winter temps in northern Canada/Greenland closely this year, to see if the low ice coverage causes an even greater warm anomaly than has been present over the last few years.

Thanks

Reply: There has been a blocking ridge of high pressure recently in that region keeping things fairly mild.

To be intellectually rigorous, I should say that I will be watching to see if there is a particularly large warm anomaly, which, if it did occur, would support those predictions which state that low arctic ice levels will lead to a significant increase in warming rate up there.

I'll be a bit liberal here in terms of expectations. Show me, at a 65% confidence level:
- Frequency and distribution of moulins in Greenland for the past 150 years
- Average moulin dimensions, same period
- Proxies of moulins for MWP

If these showed something abnormal now, I would get excited. Otherwise, ho hum .....

Charles,

ok, I quit...this must be all attributable to global warming...

Your sarcasm aside, I'm interested to see your information sources. If you have links, will you please post them?

Glaciers on Mount Saint Helens have, of course been growing since the eruption a couple decades ago simply due to the fact that all existing glaciers at the time were either reduced in size or were completely obliterated by the eruption. Water from those glaciers and from snow contributed the moisture to the lahars that swept down the mountain.

I think most people are aware of the amount of precipitation that the Pacific Northwest receives every year (I certainly am). Mount Saint Helens gets roughly 145 inches of precipitation annually, including about 16 feet of snow. Although the region is warming in general, it is still cold enough at higher elevations to support glacier formation. If it wasn't, all the glaciers in the Northwest would have disappeared long ago. On the other hand, the elevation that supports glacial development continues to rise with the temperature; glaciers on nearby Mount Rainier, Mount Hood, and Glacier Peak have been receding for the past few decades.

Changing gears, here is an explanation I found for the decline in Indian Ocean sea level:

http://stephenschneider.stanford.edu/Publications/PDF_Papers/MornerEtAl2004.pdf

And also one for Arctic sea level:

http://www.whoi.edu/science/PO/arcticsealevel/conclusions.html

To sum up, the decline in sea level in the Indian Ocean is possibly attributable to increased evaporation in the region:

In the central Indian Ocean, eustatic sea level lies well below the geoid surface because of an exceptionally high rate of evaporation (Morner, 2000). Therefore, if this evaporation increases further, sea level will fall significantly.

Changes in Arctic sea level are varied depending on the region. The Woods Hole study concludes that Arctic sea levels are rising near the coastlines and falling in the central Arctic Basin.

Also, it might be worth asking how many record highs have been set since the first of the month here in the U.S.A. I don't have the specific data, but looking at the HPRCC graph (linked below), I'd say it's highly likely that more record highs have been set across the country this month than record lows.

http://www.hprcc.unl.edu/maps/index.php?action=update_daterange&daterange=Month

In any case, none of this short term data you and I have discussed is significant unless it is shown to be part of a larger and longer trend. That said, I would still like to see your sources. If you could provide links, that would be much appreciated.

Does anyone know how to pronounce "moulin?" I need to know, for it may become a talking-point at certain parties I attend. And it doesn't matter how valid my points are at such parties; everyone sticks their noses up at me if I pronounce a word incorrectly.

Also Elliot Abrams will need to know, in order to create puns.

I tend to be distrustful of such articals, simply because they are so sensational. I used to get like Chicken Little and run around shouting, "The sky is falling," but I'm getting too old for that. The sky hasn't fallen yet, and the first end-of-the-world theory I subscribed to was back in the 1970's, and stated the end would be in 1980. When Mount Saint Helens blew in 1979 I started stock-piling toilet paper and peanut butter. The only good that came out of it was that I didn't need to buy toilet paper for a long, long time.

Notice how the piece by Paul Brown in Alternet discusses the discovery of the lake under the ice. One gets the impression recent melt-water has created the lake, and the entire icecap is being lifted and floating. In actual fact the radar which discovered the lake was only recently invented, and the lake may have been there for thousands of years.

I recall reading of a huge lake under the ice in Antarctica. I think it was discovered by setting off charges at the surface and listening to the echoes. The Russians were drilling down to investigate it, but were stopped because their drill likely would pollute the water. As I recall that huge lake was something like 100,000 years old.

Anyway, you can call me a bitter, old skeptic if you want, but articals such as this one always get my hackles up. It might be interesting to photograph my face as I read.

With all the things that happen within and below a glacier, how can we still believe in the reliability of ice-core data to estimate past climatic conditions

Jeez, if you're trolling for 'news' on AlterNet, you may as well also post links to more credible sites like Junk Science. Reply: I am not trolling for news on Alternet. That just hapened to be the site in which this story was on. Actuially one of my co-workers meteorologist Jim Andrews heard about the story and told me. Brett

This is a propaganda piece, featuring the usual suspects. If they have new data and new conclusions to advance, let them do so through the sacred "peer-review" process.

That being said, it's nice that ice-penetrating radar has been invented. Hopefully we'll now be able to acquire some reliable data. It's also nice to have these people admit the science is not settled.

Glaciers go through periods where they gallop, and periods when they slow down. Small differences in temperature drive large changes in velocity. It is normal cyclical behavior and a view over 10-20 years is meaningless.

Greenland receives about 2,000 trillion liters of snowfall every year (average snowfall 1m x 2 million km2.) It all either melts, sublimates or accumulates. All studies show that the bulk of Greenland never has any melt, and is thus accumulating snow. How many thousands of Niagara Falls would that quantity of snow fill up, without any impact on sea level?

Hysterics has no place in science.

Patrick Henry

Hysterics has no place in science!

Good point and science has found that there is a net loss from Greenland.

http://www.agu.org/pubs/crossref/2005/2005GL023955.shtml

Likewise, the IPCC has found that both conclusive proof is net loss of snow from both the Greenland and Antarctic ice sheets.

http://ipcc-wg1.ucar.edu/wg1/Report/AR4WG1_Print_Ch04.pdf

Andrew,

Over the last 650,000 years, CO2 levels have been found to vary naturally between 180 to 280 ppm. 180 ppm during ice ages. 280 ppm during warm periods. Current CO2 levels are elevated at about 385ppm. This provides a warming of the atmopshere and allows it to hold more water vapor (another greenhouse gas). So, the net result is much greater warming now than before.

So, 125,000 years ago CO2 concentrations were 280 PPM, temperatures higher than today, and sea level was 6 meters higher than sea levels today with 385 PPM CO2. Explain that one to me one more time. I fail to see the logic there. Seems to me that Greenland's ice cap should have melted about 100 years ago when CO2 concentrations were at 280 PPM.

Unless, something other than CO2 was causing the melting and/or freezing.

Mr. Bloom,

What say ye?

The bulk of Greenland has no melt, eh PH? have you been living in a cave with no communication with the outside world? See here for a nice graphic showing the progression of the melt.

Oh, and pasted below is more on the study the other Patrick linked above. Note that this is just one part of Greenland.

"Greenland is melting at record speed

"The inland ice on Greenland is vanishing much faster than scientists previously believed. This can be seen from new research results from the Danish National Space Center.

"Each year, in the south eastern part of Greenland alone, the glaciers produce a mass of icebergs which is equivalent to a gigantic ice cube measuring 6?km on all sides. And the reduction of the inland ice is accelerating. At the moment, four times as much inland ice is disappearing compared to the beginning of the decade.

"'If this development continues, the melt water from the inland ice will make the world?s seas rise by more than 60 cm this century', says senior researcher Abbas Khan of the Danish National Research Center, who was responsible for the research project. The results were obtained in co-operation with the University of Colorado and have just been published in the international research magazine Geophysical Research Letters.

"The researchers have measured the rate of melting with special, highly sensitive GPS stations placed on the mountains along the inland ice. When a quantity of inland ice disappears, the pressure on the surrounding mountains eases and they therefore rise slightly. This can be measured by the GPS stations. The measurements show that the mountains along the fast glaciers in south east Greenland are rising by 4-5 cm a year. Meanwhile, the rim of this inland ice will be 100 m thinner a year."

This is the bio of the author of the AlterNet story:

Paul Brown was the environment correspondent for The Guardian newspaper for 16 years and has worked in newspaper journalism for more than 40 years. He has written extensively about climate change, population, biodiversity, pollution, energy, desertification, and ocean management. Brown has appeared in and written television documentaries on environmental issues, contributed to books on green politics, and is the author of several books on the environment. www.globalwarningbook.com

Brett, OTOH, has used material from Steve Milloy, who is no scientist and certainly no journalist. Reply: I think I used info. from him one time, and I honestly do not remember what it was. Brett. I'm still waiting for balance.

FYI, Paul, at the time of the Eemian intergalcial the Earth's axis had more tilt such that there was a lot more high-latitude warming. IIRC this boosted the effective Greenland temperature by two or three degrees. All of the Pleistocene interglacials look a bit different due to the variance in this influence.

Interesting. Regardless of sourcing of increased energy to drive this process, its fairly safe to say the effects are accelerating - rapidly. Given the potentially catastrophic effects that severe climate change will likely pose (especially, for ex. in terms of agricultural production/ distribution - for at least a few years, until we adapt) the data coming in for years now is reason enough to tackle this problem ASAP and do what we can to minimize disruptive effects upon human society - and lives. Given that this and worse has happened before (Google Paleocene - Eocene Thermal Maximium, for ex.), might we be better served avoiding political/ personal considerations and opinions, and begin facing the enormity and complexity of a soon likely to be serious problem - and do something constructive?

The ice cores are taken from high-altitude dome locations where ice accumulates with very little melting or movement. See the EPICA site for details.

Interesting. Regardless of sourcing of increased energy to drive this process, its fairly safe to say the effects are accelerating - rapidly. Given the potentially catastrophic effects that severe climate change will likely pose (especially, for ex. in terms of agricultural production/ distribution - for at least a few years, until we adapt) the data coming in for years now is reason enough to tackle this problem ASAP and do what we can to minimize disruptive effects upon human society - and lives. Given that this and worse has happened before (Google Paleocene - Eocene Thermal Maximium, for ex.), might we be better served avoiding political/ personal considerations and opinions, and begin facing the enormity and complexity of a soon likely to be serious problem - and do something constructive?

Paul,

It takes a while to melt an Ice Sheet the size of Greenland.

125,000 years ago, the earths orbit was aligned so that the intensity of the sun at Greenland during the summer was much brighter than it is now. So, the warming from CO2 had to first overcome the lower solar irradiance before starting the melt of Greenland.

AFAIK, Greenland has only had a net loss of mass since the early 90s, but it is accelerating. Not a reason to panic, but a clear sign that it is not just an anomoly.

Be patient!

Hi Steve Bloom,

Always good to hear from you, and I fully understand that you are in love with the concept of Armageddon. But sadly (for you and your ilk) according to NASA the bulk of Greenland never sees any melting.
http://www.nasa.gov/centers/goddard/images/content/178064main_Tedesco1_lg.jpg

Given that most of Greenland is net accumulating snow, it seems unlikely to expect a huge sea level rise any time soon from Greenland melt.

About one trillion liters of water flows over Niagara Falls every month. The melt season in Greenland is about two months. Suppose two trillion liters flow through moulins in Greenland each year. That is maybe 1/100 of Greenland's annual precipitation. Niagara Falls provides some great imagery for the author to try to create panic, but it is still really lousy science.

Greenland Ice Sheet gaining mass.

"below 1500 meters, the elevation-change rate is -2.0 +/- 0.9 cm/year, in qualitative agreement with reported thinning in the ice-sheet margins," but that "an increase of 6.4 +/- 0.2 cm/year is found in the vast interior areas above 1500 meters." Spatially averaged over the bulk of the ice sheet, the net result is a mean increase of 5.4 +/- 0.2 cm/year, "or ~60 cm over 11 years, or ~54 cm when corrected for isostatic uplift."

Johannessen, O.M., Khvorostovsky, K., Miles, M.W. and Bobylev, L.P. 2005. Recent ice-sheet growth in the interior of Greenland. Sciencexpress / www.sciencexpress.org / 20 October 2005.

Note that this is just one part of Greenland.

Cherry picking, eh? As Patrick Henry links, the center ice pack is growing for a net gain in ice mass. And this is from Hansen's homeboys at NASA.

Given the potentially catastrophic effects

Silly logic, but nothing new. It is "potentially catastrophic" for you to take a shower or bath daily, so maybe we should quit doing that too? I mean it is "possible" that we could all slip and break our necks one day, leaving nobody to raise our children, right? So, no more bathing, it's "For The Children!" (TM)

Heh.

and do something constructive?
One of the AGW uber fanatics testified after Gore to Congress. He blew away all the CO2 schemes and pointed to many other issues that could be dealt with at a fraction of the cost of AGW silliness that would correct current problems and help with any potential climactic fallout.

I fully understand that you are in love with the concept of Armageddon.
The problem with AGWers is that they are positing a singularity (an event never before seen in history) where following signals become forcings, the cycle of warming then cooling is to be forever broken and negative feedbacks become positive. In layman's terms, they are claiming there is a miracle about to happen as attested to by their prophets of the great god "Science".

I may have misunderstood... but isn't arguing over the rate and time for the Greenland glaciers to "melt" missing the point? If I understand correctly, it is the increased rate of flow of glaciers into the sea that has the potential for rapid removal of glaciers - which should greatly accelerate the rate of effective "melting". The moulins, removal of the less stable coastal or border glaciers and increasing temp. should continue to accelerate this process. Distinguishing between a basic melt scenario - and one involving massive, rapid deposition of glaciers as a fractioned unit is key; one question I have is - do we have any reliable data/ means to estimate just how fast we can expect loss of mass to peak at?

"but a clear sign that it is not just an anomoly."

Please justify this statement. I am tired of alarmists pointing to short-term data sets and making claims about their significance without any analysis to back them up. Here's another example:

"And the reduction of the inland ice is accelerating. At the moment, four times as much inland ice is disappearing compared to the beginning of the decade."

Wow! That's quite a long-term data set! And no analysis or significance value to back it up.

This is not science. This is alarmism - and I repeat, don't the AGW alarmists always admonish us to pay attention to long-term trends rather than short-term anomalies?

PH clutches those cherry-picked, superceded studies to his breast as if they were a security blanket.

But since you like NASA as a source, here's a new write-up placing the recent trend in context (although it doesn't include anything from the current melt season). Melty, melty. The worst-case consequences are by no means "Armageddon," BTW, just really, really unpleasant. I'd be alarmed if I were you.

Mr. Bloom,

Thank you for pointing out that there are other causes other than the alledged CO2 demon (btw, which has such an excellent correlation with increasing temps (0.22)) that will warm the atmosphere. You would agree, then, that there are others also, eh?

On to the unprecedented melting of the Greenland Ice Cap. As Patrick Henry has pointed out in his posts, the vast majority of the Greenland Ice Cap hasn't seen liquid water for quite some time. The melting that has you and the AGW crowd in such a frenzy is below the equilibrium line at an elevation of approximately 1,200 meters. This equilibrium line is very close to the coast as can be seen in this photo. The vast majority of the 2,000 to 3,000 meter thick ice sheet hasn't seen a moulin since the last interglacial.

Therefore, it would be unwise to panic based on the tabloid-like article Brett has referenced. It will take more than 100 years to melt the 2 to 3 km of ice on Greenland. Especially if CO2 is the "only" driving force.

Any new subglacial lake is certainly not 500 m deep. This is physically possible, I suppose (Lake Vostok within the Antarctic, the largest subglacial lake, is 800 m deep) but it is at least hundreds of thousands of years old.

Quite likely there is new liquid water 500 m below the surface. WHile this is plenty to be worried about, it isn't what you've said.

If I am right, this is a disappointing enough error on a progressive news site but shouldn't be repeated here. Reply: I will try to find out. Brett. It's hard enough developing physical intuition for this stuff without misleading information being propagated.

I'd be alarmed if I were you.

Steve Bloom,

Yes, I can see (from here and other Internet forums) that you are alarmed. That is a difficult way to go through life.

Patrick H,

I went to scienceexpress.org and ran search for the paper you quoted, but the search tool didn't return a title matching the one you gave. I tried by date, and nothing regarding Greenland was publshed on October 20th, 2005. Can you provide a link?

Thanks.

Caleb, it's pronounced MOO-lin.

Paul, I get the feeling that neither you nor PH take any time reading the informative material I go to such trouble to link. Anyway:

Your two links say nothing about altitude, but even if they did they're old enough that they would definitely show a lower melt line. Melt altitude has increased a whole lot lately.

Had you OTOH looked at this prior link, you would have found that the informative graphic has this caption: "Number of the Greenland ice sheet melt days evolution from 1979 to 2006 derived from the satellite microwave data (SMMR-SSM/I) using the ImpXPGR melt retrieval algorithm. This figure shows clearly a expansion in time and space of the Greenland ice sheet melt area. The South-Dome at an elevation of 2900 m is firstly reached in 2005 (See Fettweis et al., GRL, 2007 for more details)." The paper's on the site in case you want to read it.

Is 2900 meters higher than than the 1200 meters above which you state no melting has occurred? I think it might be. I know I'm repeating myself, but this kind of making stuff up only makes you look foolish.

Here's NASA's current Greenland melt season study (from Marco Tedesco).

Steave Bloom,

Thank you for your input, but be careful of falling into actions my elders described as "the pot calling the kettle black." Psychologists call it "projection." IE: We are aware of other's shortcomings because we own those same shortcomings ourselves.

When you describe Patrick Henry as clutching "those cherry-picked, superceded studies to his breast as if they were a security blanket," it adds little to our knowledge, as a group of bloggers.

First, his data was from 2005. The data you
refer to is largely from 2005. Both are undergoing peer review, so it is difficult to say either "supercedes" the other.

I very much appreciate the link you shared: http://earthobservatory.nasa.gov/Study/Greenland/greenland4.html for it allows me to see where you are coming from.

You should be aware that Isabella Veligogna's way of measuring the ice-mass of Greenland by using satellite data is very new. So far the peer review it has recieved is largely from NASA and is friendly. It may yet have some challanges to face.

Assuming her data is correct, it is wonderful that we are able to measure with so little risk to life, using such marvelous satellites.

Her original estimate was that Greenland was losing some 248 gigatons of ice a year. (I think she revised downwards later, to 220 or so.)

This would raise the seas by only half a millimeter a year, according to the artical you linked me to. It is hard to panic about that.

She does not deny the ice is increasing away from Greenland's coasts. She merely suggests her data shows it is melting faster at the coast than it is accumulating inland.

Nor does her study state the reason for the melting. The jury is out on the cause, and I have seen very interesting evidence suggesting that at least part of the melting may be due to the warm cycle of the AMO, and may also be due to the sun's output of irradeciense and cosmic rays, (which, although stable since 1950, have been at unprecidented heights since 1950.)

If you want to see a pretty calm and interesting discussion of such things, check out the thread of comments under Brett's previous entry, concerning global warming increasing world-wide humidity.

However if you simply want to get down and dirty, and to enjoy a wild political free-for-all, check out the thread of comments under Brett's following entry concerning Al Gore. Yowza!

Hi Steve Bloom,

I am so grateful to you for providing those wonderful links and I read them studiously. I'm sure you read them carefully too and can answer these questions.

I'm wondering why you feel that referring to the NASA 2006 record Greenland melt data is "cherry picking?"

Also, I'm curious how vast regions of the Greenland ice sheet which receive about 1m of snow per year and never see any melting, could not be accumulating ice? I would have thought that your man at NASA might have thought that through before publishing this map.
http://earthobservatory.nasa.gov/Study/Greenland/Images/greenland_elev_change_rt.jpg

Perhaps Santa Claus is sucking the excess snow up in his giant vacuum cleaner? Or perhaps neither conservation of mass nor energy is important in AGW theory?

Thx for the entertainment. I really do appreciate it!

Patrick,

Also, I'm curious how vast regions of the Greenland ice sheet which receive about 1m of snow per year and never see any melting, could not be accumulating ice? I would have thought that your man at NASA might have thought that through before publishing this map.

Perhaps that's why he added the caption?

From the explanation provided, found directly to the right of the map:

Using ICESat data, scientists calculated the change in thickness of the Greenland Ice Sheet between 2003 and 2006. Increased melting and faster glacial flow lowered the surface along the margins of the ice sheet (brown), while increased snowfall thickened the ice in the interior of Greenland (blue). This pattern is consistent with model predictions of how global warming will affect the ice sheet.

http://earthobservatory.nasa.gov/Study/Greenland/greenland5.html

Apparently you didn't read studiously enough.

Hi Travis,

If you look at the center of the ice sheet on the NASA map, it shows no thickening. Obviously this is incorrect.
http://earthobservatory.nasa.gov/Study/Greenland/Images/greenland_elev_change_rt.jpg

Also, there is no indication of increased snowfall in Greenland. Ice has been accumulating in the center for a very long time.

I flew over Greenland yesterday and the ice sheet looked amazingly thick and consistent as ever. The only thing I noticed which was unusual was that the ice along the western periphery of the sheet was extremely dirty. The dirt may have blown up from the beaches or perhaps over from Canada. Plenty of new sea ice already forming on the eastern side.

Mr. Bloom,

Had you OTOH looked at this prior link,...using the ImpXPGR melt retrieval algorithm...

I noticed that this algorithm has only been used by Dr. Fettweis and his cohorts. Until it has been used by a few more people, I think I'll remain a bit skeptical of the graphs generated by Dr. Fettweis. Essentially, this algorithm is just another model which we are suppose to accept at face-value. Personally, I'm not sure if we are being Hansened or not.

Is 2900 meters higher than than the 1200 meters above which you state no melting has occurred?

equilibrium line - The boundary on a glacier between the ablation area and accumulation area. No net mass is gained or lost at this location. In the absence of superimposed ice, this line is equal to the snow line at the end of the mass balance year.

Mr. Bloom, I've provided the above definition for your education. This definition is consistent with my previous comment. Even if Dr. Fettweis graphs are to be believed, the number of meltdays above 2900 meters at the South Dome is less than 10 or so. I would not expect the formation of moulins in areas above the equilibrium line. There is just not enough melting. So, my comment still stands.

These scientists don't know what they're talking about. I mean, did you know that Patrick Henry flies over Greenland all the time? He can measure the temperature and the thickness of the ice from his window seat on the plane. He even counts all of the polar bears. NASA is just wasting money on their satellites and NOAA should just scrap their weather stations in Greenland. Why invest all that money when we have Patrick Henry taking those measurements from his window seat while he's munching on some pretzels.

Plenty of new sea ice already forming on the eastern side.

Yes, Patrick, this is what happens when we approach winter in the northern hemisphere. Current Greenland sea ice levels? About normal.

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.5.html

FYI, the negative sea ice anomaly has become even more pronounced since September as a result of the substantially delayed re-freeze. Now it goes off the bottom of the charts (note the new record negative anomaly):
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.anom.jpg

Or for more detail:
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/sea.ice.anomaly.timeseries.jpg

Since I know you'll want to mention the Antarctic sea ice maximum, I'll bring it up for you. The ice has melted faster than normal down south; in just 15 days, the positive 1 million km2+ anomaly has completely disappeared. In other words, Antarctic sea ice is now at normal levels, and if the recent trend continues, we will soon see negative anomalies. In fact, Antarctic sea ice levels are lower than they were at this time last year.

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.365.south.jpg

This highlights what I've been saying for the past few months about how insignificant Antarctic sea ice levels have been. Arctic sea ice has not been above normal since early in 2003. Antarctic sea ice was below normal seven weeks ago. Do you see any difference of significance?

For now I'll grant you the blank spot in the center of the Greenland map. I have no expert explanation for the apparent lack of elevation increase. My best explanation is that the ice accumulation in that region over the past few years has been insignificant compared to accumulation further south and the melt along the coasts.

I consider this especially likely since most of the moisture and storm fronts approach from the south and southwest (Brett, correct me if I'm wrong there), which is where you see most of the ice increase. Compared to the amount of snow this likely generates, a meter of snow per year in the interior is hardly worth mentioning. For comparison: here in Washington, Mt. Saint Helens gets five or six meters of snow per year. Besides, as you have been fond of pointing out, it is very cold in the central interior and as we know, cold air holds very little moisture. At any rate, I'm fairly certain there is not an anti-capitalist conspiracy in the works at EO.

I flew over Greenland yesterday and the ice sheet looked amazingly thick and consistent as ever.

Really? Did the airplane circle the entire island a couple times so you could get a good view? If not, you must have awful good eyesight to see the entire island from the southern tip to the north end 1600 miles north. I typically have a lot of trouble seeing Seattle from LA at 35,000 feet, and that's only 1000 miles.

Having said that, the Greenland ice sheet is not going to disappear within the next 20 years, nor do I find it likely it will go away in the next 100. But I do expect it to continue the trend of net ice mass loss for the foreseeable future. At some point, the natural variability of the earth's climate will cause the NH to cool a bit, but temperatures will likely remain higher than normal in context of that natural variability. Then it will increase again to higher levels than we see today and the melt will accelerate again.

The only thing I noticed which was unusual was that the ice along the western periphery of the sheet was extremely dirty. The dirt may have blown up from the beaches or perhaps over from Canada.

So would that be from the environmentally unfriendly Inuit farming practices, climate scientists holding dune buggy races, or from the burgeoning construction industry on Baffin island?

All kidding aside, if you're blaming this dirt for the anomalous melt, I'd like to point out that this melt has shown a consistent progression for more than a decade. If what you've seen is abnormal, that suggests that the pattern of increased melting we've been seeing for some years now is unrelated to your observations.

Keep trying.

Paul, I know what an equilibrium line is. Recall that your prior post said: "On to the unprecedented melting of the Greenland Ice Cap. As Patrick Henry has pointed out in his posts, the vast majority of the Greenland Ice Cap hasn't seen liquid water for quite some time. The melting that has you and the AGW crowd in such a frenzy is below the equilibrium line at an elevation of approximately 1,200 meters." Wrong, wrong, wrong. But then they don't call it denial for nothing.

BTW, you're absolutely right that there isn't yet a great deal of melting at higher altitudes. The problem is that there is a sharp trend toward much more of it.

Mr. Bloom,

Wrong, wrong, wrong. But then they don't call it denial for nothing.

As I stated in my previous post, "I would not expect the formation of moulins in areas above the equilibrium line." That is exactly the point of origin for the AGW hysterics, moulins. Not if there is insignificant melting at the highest elevations (BTW, less than 10 days/year melting is insignificant.)

So it's the moulins that are important! That would explain all the surveys of moulins that have been done. But, er, Paul, there aren't any such surveys.

Counting the moulins or measuring the flow into them would be a bit like counting the icebergs discharging from the big outlet glaciers. It's connected to the melting, all right, and might even be fun to do, but in and of itself it's not useful in characterizing the mass loss.

Paul, odds are that eventually one of your flights of fancy will turn out to be right. We can but await that day.

Mr. Bllom,

Counting the moulins or measuring the flow into them would be a bit like counting the icebergs discharging from the big outlet glaciers. It's connected to the melting, all right, and might even be fun to do, but in and of itself it's not useful in characterizing the mass loss.

Thank you, my point exactly. I could care less how many moulins are in the glaciers or that they are even forming. However, the AGW fanatics are going nuts over this in the article. Thanks for proving my point.

Mr. Bllom,

So it's the moulins that are important!

If you would read the post instead of objurgating, you would have seen this line:

Well, on a recent trip to Greenland a group of scientists and journalists were alarmed at the size and number of these moulins that they saw on the Greenland ice cap.

Duh, am I going to have to find you a clue? Obviously, you don't have one.

Here, let me point out the key words for you; scientists, alarmed, size, number, moulins, Greenland, ice, cap.

There, got it? Probably not. Now, you be careful up there in that ivory tower that you've built. I wouldn't want you to fall and hurt yourself.

Thank you, my point exactly. I could care less how many moulins are in the glaciers or that they are even forming. However, the AGW fanatics are going nuts over this in the article. Thanks for proving my point.

Paul once again rather stunningly misses the entire point of the thread. This thread is not about (a) CO2 (b) Greenland melting (c) number of moulins or (d) flow into or out of moulins.

This thread is about the mechanism by which the Greenland moulins, which are much larger and more plentiful than expected, accelerate the rate at which Greenland's glaciers slide into the ocean.

From the thread-starter:
Some of the moulins in Greenland run on the scale of Niagra Falls and are helping the glaciers to move at three times the rate that they did previously.

Scientists say the acceleration of melting and subsequent speeding up of giant glaciers could be catastrophic in terms of sea level rise and make previous predictions published this year by the Intergovernmental Panel on Climate Change (IPCC) far too low, according to the article from AlterNet, which is a progressive news website. (emphasis mine)

Let's see that on instant replay:
1) [The moulins] are helping the glaciers to move at three times the rate that they did previously.

2) The acceleration of melting and subsequent speeding up of giant glaciers could be catastrophic in terms of sea level rise.

In spite of Paul's heroic efforts to distract us, the relevant questions for Paul are:

- Do you dispute the claim that these moulins speed the rate at which Greenland glaciers move, and why?

- Do you dispute the resulting claimed catastrophic increase in sea level rise, and why?

bt,

Do you dispute the claim that these moulins speed the rate at which Greenland glaciers move, and why?

Not really, it's called surging and is a normal occurrence in glaciers of all sizes and shapes. The author of the article acts like this is some previously undiscovered fact. I would go into how this works, but given your superior intellect; I'm sure you already know how it works. And since you already know how it works, you also know that surging is a temporary phenomena. This is just another attempt at scaring the unsuspecting public.

Do you dispute the resulting claimed catastrophic increase in sea level rise, and why?

Yes, surging is temporary and cyclic just as the current warming is temporary and cyclic. More scare tactics.

At last we finally seem to be on-topic.

Paul writes:
... it's called surging and is a normal occurrence in glaciers of all sizes and shapes. The author of the article acts like this is some previously undiscovered fact. I would go into how this works, but given your superior intellect; I'm sure you already know how it works. And since you already know how it works, you also know that surging is a temporary phenomena. This is just another attempt at scaring the unsuspecting public.

From the thread-starter:
Professor Robert Correll, chairman of the Arctic Climate Impact Assessment said that newly invented ice penetrating radar showed that the melt water was pouring through to the bottom of the glacier creating a melt water lake 500 metres deep causing the glacier "to float on land. "These melt water rivers are lubricating the glacier, like applying oil to a surface and causing it to slide into the sea. It is causing a massive acceleration which could be catastrophic." Correll stated that one particular glacier puts enough fresh water into the sea in one day to provide drinking water for a city the size of New York for a year.

I'd like Paul to show a peer-reviewed cite or two that shows that a 500M deep melt-water lake is a "normal occurrence" in any glacier, never mind "glaciers of all sizes and shapes".

Yes, surging is temporary and cyclic just as the current warming is temporary and cyclic. More scare tactics.

I'd like Paul to offer a cite showing the distribution of the size, in volume, of these "normal" surges, and where the hypothesized Greenland event fits in that distribution.

In particular, if a particular volume of glacial ice moves from land to sea, perhaps Paul can describe where the displaced sea-water goes if there is no corresponding increase in sea level.

I'd like Paul to show a peer-reviewed cite or two that shows that a 500M deep melt-water lake is a "normal occurrence" in any glacier, never mind "glaciers of all sizes and shapes".

Yoshi!! Lake Vostok in Antarctica comes to mind. From the NSF report convened at Columbia University (is that good enough for you, bt. Maybe I should vet all my references through you from now on. NOT!!): "The water depth varies from approximately 500 m beneath Vostok Station to a few 10's of meters at the northern end of the Lake; the ice sheet thickness also varies by nearly 400 m and is thickest in the north (4,150 m)."

This "lake" is 250 kilometers long by 40 kilometers wide and is 400 meters deep: approximately the size of Lake Ontario! It is thought to occupy a structural basin (you know what that is, eh, bt?)

Lake Vostok is the largest of some 70 to 146 similar lakes beneath the ice in Antarctica. I don't think the Antarctic Ice Cap is in eminent danger of sliding into the ocean, either.

A PowerPoint presentation documents the discovery of at least two subglacial lakes in northeastern Greenland in 2006. The huge subglacial lake referenced in the article associated with this thread is on the western coast of Greenland.

Here's another, Grimsvotn subglacial lake, Vatnajokull, Iceland. Iceland? Who'da thunk that there would be subglacial lakes in Iceland? This lake is only about 200 m deep.

This paper is interesting in that it documents surges in a glacier in East Greenland 495 and 95 years ago.

There is also evidence that many of the large lakes in the Canadian Shield are the remnants of subglacial lakes, many of them quite large. In fact, I wouldn't be surprised if the Great Lakes are the remnants of subglacial lakes from the last few ice ages.

Why have more not been discovered in Greenland? Probably because they haven't been looking due to lack of funding. I'm sure some enterprising glaciologist is writing a grant request for this work as I type. Another possible reason is the lack of structural basins in which the water can collect. In the article above, there is no indication of the structural setting of the lake. If the lake is sitting in a structural depression, there is a good chance that it may not be greasing the skids as the good doctor suggests.

Many subglacial lakes in smaller glaciers have not been recognized or are not in the literature because of their small size. Yet, there is evidence of their existence. Have you ever heard of a jokulhlaup?

This 1987 paper links glacial surge in an Alaskan glacier (this, bt, would be one of the glaciers on the small end of the all sizes and shapes) to backing up of water in cave and tunnel systems beneath the glacier. Technically, any backup of water in a cave or tunnel beneath a glacier is a subglacial lake or pond.

That's all for now. I'll get to the rest of your requests for knowledge a bit later. I'm glad to see that you are becoming inquisitive.

I'd like Paul to offer a cite showing the distribution of the size, in volume, of these "normal" surges, and where the hypothesized Greenland event fits in that distribution.

Here you go, Bubba. This is a paper about one of the Greenland glaciers. Glacier movement in this glacier was "...6,700 m/yr in 1985 to 5,700 m/yr in 1992..., ...9,400 m/yr by 2000 and 12,600 m/yr in 2003..." Does this qualify as surge, bt? If so, I find these remarks by the authors quite interesting,"These changes are consistent with earlier evidence for thickening of the glacier in the early 1990s and rapid thinning thereafter." Wait a minute. Where's the subglacial lake aspect for this glacier?

Then there's this statement towards the end of the paper. "Meltwater input to the bed seasonally affects nearby inland ice speed, but these fluctuations are far smaller than the changes we observe. Although we have only coarse intra-annual sampling, our results suggest a trend of increasing speed starting after 1997, rather than a seasonal pattern of summer speed-up and winter slowdown. The speed-up appears to persist through the winter, so it seems unlikely (emphasis mine) that increased surface-meltwater input to the bed directly caused the acceleration.

I'm going to let you do the rest of your research on your own nickel. If you want an advanced degree, there are couple of schools there in your neighborhood that would gladly take your money.

Anata wa tanoshimu!!

I'm glad to see Paul offering cites with real substance.

Paul's powerpoint cite offers several items of interest.

On page 25 (of 70), it observes that Lake Vostok "is the largest known subglacial lake". About half of it's surface area is on the order of 10M deep. Do we know what the area or volume of the cited Greenland feature is? Are there comparable structural basins under the Greenland ice? Somehow, I doubt it.

Meanwhile, I note that the summary of the same powerpoint says (p69 of 70):

• Detected motions are astonishing in their magnitude, dynamic nature, and spatial extent


• Time-scales for subglacial water transport is short compared with other known drivers of glacial flow variability


• The rapid variation in lubrication conditions provides a mechanism for rapid changes in ice stream behavior

It appears to me that this reference cited by Paul supports, as opposed to challenges, the assertions of the thread-starter. For example, the choice of "astonishing" does not, to me, signal a "normal occurrence in glaciers of all sizes and shapes".

Paul, your last link (to a Nature reprint, I think) appears to be scrambled, can you try again please?

In the meantime, let's please try to stay on-topic. The second question is whether a large surge might result in a catastrophic increase in sea level rise, and why.

I'm going to let you do the rest of your research on your own nickel. If you want an advanced degree, there are couple of schools there in your neighborhood that would gladly take your money.

The assertions were yours, not mine. You claimed that these phenomena were "normal". When I asked you to support that claim, you've responded with cites that seem to instead weaken it.

If you aren't prepared to support your claims, I wonder why you think we should be prepared to accept them.

bt,

Here is the pdf, sorry you can't figure out how to fix the link.

Did you not read anything that I wrote or linked to? Or did you just cherry-pick what fit your preconceived ideas? I know that you and your AGW cheerleaders can only think in terms of the last 30 years or so. Therefore, I wouldn't expect you to accept any evidence from the last glacial epochs. However, for grins and giggles, let's look at some evidence of subglacial lakes over a time span greater than that of your time here on earth.

Lake Vostok has been around anywhere between 15 million and 400,000 years. The first date puts the age at the formation of the Antarctic ice sheet and the second age is the age of the oldest ice prior to hitting the surface of the lake. The Wisconsin glaciation began about 115,000 years ago, so Lake Vostok predates the Wisconsin, Illinoian, and Kansan ice ages and probably predates or was formed at the same time as the Nebraskan ice age. Lake Vostok is an Ice Age relic.

Many, if not all the lakes in the Canadian Shield area are the remnants of subglacial lakes from at least the Wisconsin. For instance, Christie Bay in the NE arm of the Great Slave Lake is a >600 meter deep analog to Lake Vostok.

One other item that I noticed in the thread article is that there is no mention of the age or areal dimensions of the Greenland subglacial lake. They make it sound as though it has only formed in the last few weeks. Somehow I doubt it.

You also state that you doubt if there are any subglacial structural features in Greenland. Well, there you have it. bt has spoken!! Nothing to see here, folk, move along.

As to your second question, no. The mass balance of the ice cap of Greenland is such that the total mass balance is increasing. This has been shown in a satellite survey (I'd have you look it up yourself, bt, but you'd start whining.). So, no, surges aren't going to have much of an overall effect on sea levels.

I wonder what effect the warming during the 1920s and the Medieval Warm Period had on global sea levels? Since you think that this melting is unprecedented, how about providing me with a citation or two on the lack of sea level rise during previous warm periods?

Also, see if you can find out how old the recently discovered subglacial lake is in Greenland?

And while you're at it, please provide some citations on why you doubt that there is any structural basins in Greenland. Until you can provide some citations, I don't think we can accept your claim.

After reading the various posts re natual cycles, I'd like to weigh in with info picked up from Natural History Magazine concerning Milankovich cycles which coincide remarkably well with the cycles portrayed by Gore. Acocrding to these, we should be in a cooling trend.

Far North Science had an interesting article re Greenland melting last month (9/26 if I recall) which showed that melt was 150% HIGHER at higher altitudes. If that water is collecting in a lake beneath the ice, one wonders how much upward pressure is exerted on the ice AND if that water flows out suddenly, what effect will 'isostatic rebound' have on the rest of the ice sheet. I also wonder if that melting is coincident with a deeper indentation in the mantle and if geothermal heat accounts for some of the melt.

Finally, one other 'anecodatal' report, shrubs are moving north with one report saying it is the equivlent of the trimberline rising 650 feet.

This is a fascinating subject and I appreciate the comments given.

Roth