On endless ice, searching for clues to our future

Aug 15, 2011 By CHARLES J. HANLEY , AP Special Correspondent
In this July 19, 2011 photo, attached by rope to a waiting helicopter, Arctic researcher Carl Gladish of New York University hammers a steel stake into ice, securing a newly-deployed GPS seismometer, or Geopebble, designed to track glacial movement near the edge of the Greenland ice sheet, atop Jakobshavn Glacier, outside Ilulissat, Greenland. The chief researcher, NYU's David Holland, hopes to eventually deploy scores of the devices to help measure ice loss in Greenland. (AP Photo/Brennan Linsley)

(AP) -- The pilot eased his five-ton helicopter toward the glacier's rumpled surface, aiming for the lightest of setdowns atop one of the fastest-flowing ice streams on Earth.

David Holland's voice suddenly broke in on the intercom.

"Carl doesn't like this!" the scientist shouted. "Carl says it's snow bridges!" - drifts that can hide a deep crevasse.

The chopper pulled up sharply and veered off over the chaotic icescape of white knobs and pinnacles and bluish glints of , on to another, safer landing spot where Carl Gladish, Holland's lanky, ponytailed assistant, stepped cautiously off the skid and onto the , under the thudding , to swiftly carry out his assigned task.

It was one of eight 2-minute touchdowns on which the New York University research team positioned instruments to measure the movement and internal cracking of Jakobshavn Glacier, a risky operation meant to shed light on one more tiny piece of the giant puzzle called Greenland.

Other scientists elsewhere were working on their own pieces, on demanding and often dangerous missions, sometimes in subfreezing temperatures and high winds, sleeping in tents on the ice, isolated for weeks at a time, linked tenuously by .

On this same July day, Alun Hubbard was on a solitary trek to the north coast's spectacular, remote . Liz Morris was in the first hours of a monthlong research traverse along the hump of Greenland's vast, 3-kilometer-thick (2-mile-thick) ice sheet. Asa Rennermalm and her colleagues, at the ice's western fringe, were in their fourth summer of meticulous, tedious sampling of the meltwater flow from the interior.

Scattered across the world's largest island, as big as Alaska and California combined and 80 percent covered by ice, small bands of specialists tended to GPS sites and automatic weather stations, drilled down into the island's frozen cap, and analyzed the air and clouds overhead, working long hours under the midnight sun to help begin answering a crucial question:

How much of Greenland's ice will melt, and how quickly, in a world growing warmer, and warming fastest in the Arctic?

If all the ice eventually slipped into the ocean, it would be enough to raise global sea levels by 7 meters (23 feet). Even a fraction of that would inundate Bangladesh and south Florida, drown small islands, threaten Shanghai and New York.

But as temperatures rise from greenhouse gases in the atmosphere, the answer isn't coming easily. The challenge - scientific, logistical - appears greater than the resources devoted to it.

This Greenland puzzle, and uncertainty over Antarctica's ice, led the U.N.-sponsored Intergovernmental Panel on Climate Change to essentially disregard the impact on oceans of an accelerating polar melt. In its 2007 global warming report, the IPCC projected a sea-level rise of only 18 to 59 centimeters (7 to 23 inches) this century, mostly from water expanding when warmed.

But researchers have since determined that Greenland lost ice in the 2004-2009 period four times faster than in 1995-2000. This May, the eight-nation Arctic Monitoring and Assessment Program forecast a much higher global sea-level rise - of 90 to 160 centimeters (35 to 63 inches) by 2100.

To those best informed, like Cambridge University's Morris, a polar research veteran, melt is inevitable in a place where temperatures over the ice sheet have risen by 2.2 degrees C (4 degrees F) in just 20 years.

"There's no way that you put greenhouse gases into the atmosphere and it won't warm and the ice won't melt," she said before setting out on her snowmobile expedition. "The uncertainty is when."

The "when" hinges on a web of variables in what Morris called Greenland's "massively complex" ice system.

When and where, for example, are warmer southern waters reaching Greenland's fjords, spreading under their glaciers? How effectively is meltwater percolating from the ice sheet's inland surface to its base, lubricating movement toward the sea? How much does snowfall - water drawn from the oceans - offset the melted ice?

Researchers long focused on southern outlet glaciers like the west coast's Jakobshavn, an awesome iceberg producer 6 kilometers (4 miles) wide, believed to be the Northern Hemisphere's biggest single contributor to ocean rise. The ice where doctoral candidate Gladish did his quick work is streaming toward the sea at a rate of 30 meters (100 feet) a day, twice as fast as in the 1990s.

The big melt is now moving northwest. Last year, U.S. and Danish scientists reported that "crustal uplift," the rising of land as the weight of ice melts away, was detected far up the coast.

"There are big red zones, big thinning rates going on in the far northwest, and that's bizarre because it's meant to be very cold up there," said Hubbard, of Wales' Aberystwyth University.

The ruggedly built British glaciologist spoke with a reporter at Kangerlussuaq, a southern research hub, hours before helicoptering off on a one-man mission to collect GPS and other data from Petermann Glacier, just 1,000 kilometers (600 miles) from the North Pole.

A year ago, a 290-square-kilometer (110-square-mile) piece broke off giant Petermann and into the sea - a chunk of ice three times the size of Manhattan island.

But Hubbard, like others, said intensive research is now most needed deeper in the interior, to learn how the main body of ice is reacting to longer, warmer summers, and particularly whether meltwater pouring down to its base might cause "runaway instability" in the ice sheet.

He said the melt has moved inland up Greenland's icy dome to 1,500 meters (5,000 feet) elevation, some 120 kilometers (75 miles) in from the ice cap's edge.

This summer a U.S.-Swiss team was drilling boreholes into the ice sheet northeast of Jakobshavn Glacier to better understand how ice movement detected by GPS stations relates to the "plumbing," the under-ice meltwater system the boreholes find below.

Far up the slope, at the 3,200-meter-high (10,500-foot-high) frigid heart of the ice sheet, the U.S. National Science Foundation (NSF) maintains its remote Summit Station research site, serviced by big New York Air National Guard LC-130 transport planes equipped with ski landing gear for the ice runway.

In small labs bristling with rooftop sensors, American researchers at Summit upgraded their instruments this summer to better study cloud formation and thickness, precipitation, the reflectivity of the snow and ice, and the presence of "black carbon," falling soot, that would dim that reflectivity and absorb warming sunlight.

Snowfall is key, but "we know so little detail about Greenland," said Summit visitor Erica Key, an Arctic program manager for the NSF, a major funder of Greenland research.

"Most models" - computer climate simulations - "block out Greenland as a black box," she said.

It was in Summit's thin air that 64-year-old Morris, her 155-centimeter (5-foot-1) frame bundled in orange cold-weather gear, set out with assistant John Sweeny on a one-month, two-snowmobile mission to supply her piece of the puzzle: measuring the snow density along a 400-kilometer (250-mile) route, to give the new European Cryosat 2 satellite some "ground truth" data to compare and calibrate with its own remote readings of ice thickness.

Those readings are badly needed. The European Union's first ice-surveying satellite failed on launch in 2005, and NASA's ICESAT orbiter stopped working in 2009, not to be replaced until at least 2015.

Any hard-won data emerging on the ice sheet's dynamics would help refine computer models for a better fix on how a warmer Greenland will produce higher seas. But modelers are short not only on satellite readings, but also on ground observations from a too-thin corps of scientists.

Below its gravelly fringe, near Kangerlussuaq, Rennermalm's team was measuring the volume of meltwater gushing down stream beds from the ice sheet - at up to 2.3 meters (7.5 feet) per second. But this was only one spot on a huge white map.

"I want to understand how much water is coming from the ice sheet," said the Danish researcher, a leader of the Rutgers-UCLA project. "But there are very few measurements like this in Greenland. This is a difficult place to do science, a logistical challenge."

Back up at Summit, two young Dartmouth College engineering graduates put one potential answer on display, testing the tiny, tractor-like "Yeti" autonomous robot over the ice. Like humans, Yeti could deploy ground-penetrating radar, meteorological gear and other research tools, say its designers, who envision hundreds crisscrossing Greenland offering up-to-the-minute data.

Someday. For now, NYU's Holland has opted for ringed seals, two sea mammals he fitted with instruments for recording temperature and depth in a southeastern fjord of interest - "researchers" whose findings were transmitted by satellite back to his NYU lab.

But two seals against 44,000 kilometers (27,000 miles) of Greenland coastline still come up short.

Solving the problem, said the veteran glaciologist, means accurately forecasting sea-level rise for particular regions over particular time periods. And "we don't have that capability yet."

He sees gaping holes: a need for new technology to comprehensively measure ocean temperatures; a need for an icebreaker dedicated to research in colder seasons.

"We are making a really noble effort," Holland said. "But if you ask me whether we are making adequate progress at an adequate pace, I'd say no."

The authoritative Arctic Monitoring and Assessment Program, in its May report, seemed to agree. Greenland's ice sheet is expected to melt faster and faster, but the impact remains highly uncertain, it said, and only "more robust observational networks" can change that.

"The Fate of Greenland," a new book co-authored by glaciologist Richard Alley and other leading U.S. scientists, offers stunning photos of an extraordinary white world, and dark words of warning.

"Our lack of fundamental understanding of ice-sheet behavior leaves open the possibility that we could be greatly underestimating the rate of response to warming, with potentially major implications," they write.

The world must pay attention to Greenland, these scientists say, "because in the fate of Greenland lie clues to the fate of the world."

Explore further: Hurricane Edouard right environment for drone test (Update)

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Techno1
1 / 5 (4) Aug 15, 2011
I guess everyone has this mental image of ice on gently sloping terrain gradually melting away, and sea levels gradually rising so that people have time to respond...

Reality might not be happening in quite so benevolent of a fashion.

We could see large chunks of glaciers break away, causing land-slide generated tsunamis as the ice and the suspended rock and soil debris it carries falls off into the water.

If a collosal failure of the entire GLACIER happens, causing a giant tsunami that circles the globe, and also permanently raising sea level by like a FOOT in one day, what will be the consequences of that?
Techno1
1 / 5 (3) Aug 15, 2011
But researchers have since determined that Greenland lost ice in the 2004-2009 period four times faster than in 1995-2000. This May, the eight-nation Arctic Monitoring and Assessment Program forecast a much higher global sea-level rise - of 90 to 160 centimeters (35 to 63 inches) by 2100.


That would suggest the rate of melting for a 5 year period is doubling every 5 years.

This would give an approximate coefficient equal to 2^(1/5), or 1.1487, for the exponential curve, a^n, where a is the coefficient and n is the number of years.

This would mean that in 5 years, greenland will be melting twice as fast as it is now, and in 50 years, it would be melting 32 times as fast as it is now.

This is similar to the regression I calculated, in which the arctic sea ice melts, on average, cumulatively at a rate of abou 3%, or a coefficient of 1.03^n, where n is years, but this was calculated for the 15% extent, which is deceptive, because it doesn't figure how badly...cont...
Techno1
1 / 5 (3) Aug 15, 2011
cont...

It didn't figure how badly the volume was lost due to the shrinking of the sea ice at other benchmarks: 30,50,70,100, whatever.

After visually looking at the sea ice minimums on the actual maps, it's clear the volume of sea is is decreasing significantly faster, on average, as compared to the 15% extent. Infact, it seems the minimum volume sea ice has decrease every year for at least 10 years or so, and the rate of decrease is very high and far along on the curve.

In the end, on the Sea Ice, it doesn't even matter what the coefficient is, 1 or 2 percent only extends the time to the first complete meltdown of sea ice by a year or two.

My low end estimate, based on the 15% extent, had been 15 years, or 2026 for the first complete meltdown, however, the VOLUME of sea ice is actually melting faster than that, or at least has been for the past 10 years, which is shocking.

It may be replenished somewhat by calving in Greenland, but that isn't good either.
Techno1
1 / 5 (3) Aug 15, 2011
So this means that the first complete meltdown of the sea ice will happen on or before September 2026.

At that time, changes in albedo and greenhouse gases will mean Greenland's ice will be melting, on average, at least 8 times faster than it is currently melting.

So this means Greenland will melt slightly more in the next 5 years than it did in the previous 15 years combined...
Techno1
1 / 5 (3) Aug 15, 2011
Above, in my second post, I typed "50" and meant "25".

25 years / 5 years average per doubling = 5

2^5 = 32 times melting rate.

50 years / 5 years average per doubling = 10

2^10 = 1024 times melting rate.

This might seem outrageous at first, considering you might argue the earth would need to warm drastically to get the melting that high. It doesn't.

Once you remove a few square meters of ice, the increased NET solar input in the ocean in the arctic is approximately 160WATTS per meter square.

This is enough extra energy such that if all of it goes into melting ICE, it can melt a CUBIC LITER of ice at 0c to water at 0c in 2063 seconds, or 34 minutes 23 seconds.

Since there are 12 hours in a day for the portions of the season that have daylight (I know its different in the artic where they have nonstop day during summer, but I'm using simple numbers,) then that is 43200 seconds.

43200s / 2063s per liter melt = 20.94 liters per day.
Techno1
1 / 5 (3) Aug 15, 2011
So every square meter of ice that is missing vs the "normal" then allows enough additional net solar input to melt an additional ~21 LITERS of ice during a 12 hours day.

Now if you had 21 liters of ice and it is 1cm thick, a liter is 1000 cubic cm, and a METER of ice at 1 cm thick would be 10,000 cubic cm (100*100*1).

Now 21 liters at 1cm thick is 21,000cubic cm, and divice that by 10,000cubic cm, gives 2.1 square meters melted.

So every 1 meter of area that you start out "below normal" means that you will melt 2.1 more meters of area per day at 1cm thickness, OR 1 more meter per day at 2.1cm thickness.

However, this is itself an underestimate, since you must solve a geometric series, since the ice that is melting reveals some extra surface during the day as it melts.

It turns out, if you solve geometric series, the ice is melting twice as fast as it appears to melt, giving an actual value of 4.2 square meters at 1cm thickness for every 1 square meter missing initially
Techno1
1 / 5 (3) Aug 15, 2011
Now, because of the laws of thermodynamics, any increase in the net thermal input is more likely to go into paying to raise the temperatures of sub-zero ice than the environment around itself, and then any further increase in net thermal input, is more likely to eithe rmelt ice, or raise the temperature of 0c water, than it is to raise the temperatuer of adjacent 1c water.

Therefore, MOST of the excess heat is going into melting ice, which then allows more and more excess heat to get in as solar radiation absorbed by water or land.

I'm sure everyone understands the basic feedback mechanism of decreasing albedo, but it may be that people haven't necessarily seen or done the mathematics of how devastating it actually is.

While the 15% ice extent bounces around a bit due to variations in weather, the rate of melting of the total volume of sea ice and greenland glaciers is pretty much in a runaway meltdown.

A free-fall even...
Techno1
1 / 5 (3) Aug 15, 2011
Now here is a wonder.

If in the past, during the ice age, there was thrice as much area of glacial ice as there is now, yet THAT ice melted in time over thousands of years, in spite of what should have been a significantly higher average albedo for the planet...

Then why should anyone be surprised if Greenland and Antartica ice caps continue to melt, now that the average albedo of the Earth is around 10 points or so lower than it would have been at the peak of the Ice Age?

The "natural" net solar input is higher now than it ever has been in recorded history.

Roughly 2/3rds of the world's ice melted before the Pyramids were even built.

Why would you be surprised if the remaining 1/3rd melts as well?

Why would you be surprised if the rate of melting exponentially increases? It would be an exponential increase in melting even without CO2, simply because of changes in albedo due to the previous melting...
Techno1
1 / 5 (3) Aug 15, 2011
So I would conclude that this melting is natural, and is not man made, because the rate of increase in melting actually recorded (see article above,) agrees, approximately, with a regression that ignores changes in CO2...

So just the positive feedbacks from changes in albedo caused by prior melting is sufficient to explain the increase in further melting, without regards for CO2 at all...

The only thing that keeps the ice from melting within a few years from now is of course the negative feedbacks, and the biggest one of those are here:

1) Night time
2) Winter time
3) A "hot" object radiates heat away faster as IR radiation, so the more the earth warms, the harder it is to keep warming in that regards.

4) Ice is a thermal insulator, which Ironically traps heat in water below itself, making it harder to radiate away heat. Therefore if you melt the ice on the surface, then the effects of 3 above increase, giving even more negative feedback.
Techno1
1 / 5 (3) Aug 15, 2011
However, the change in Albedo is so powerful that all of those negative feedbacks combined are not enough to stop it, even though 3 and 4 above grow more and more as the amount of ice decreases and the temperature rises, but so far, they are not growing as fast as the increase in solar input due to decrease in albedo.

In fact, in the past 10 to 15 years, we seem to have gotten over a "hump" in the curve whereby the change in albedo is actually accelerating away from the change in the negative feedbacks, which can be clearly seen here:

http://nsidc.org/...ure2.png

http://nsidc.org/...icenews/

http://nsidc.org/...ure3.png

You can see here, on figure 3, that if you take the 5 year running average for the past 5 years, it is actually below the blue line for the linear approximation of the 30 years trend, having a value of 8.44 in m km.

This means that the rate of ice loss is accelerating rapidly.
Techno1
1 / 5 (3) Aug 15, 2011
Even if you average the past 7 years, you get a value of 8.53 m km, which is still below the end of blue linear trend line by about 100k km square.

it's clear that if you plotted in terms of 5 year running averages, and if you fit a quadratic regression curve instead of a linear trend, it would show that the rate of annual net melting is accelerating very much...

I wonder what sort of vegetation Greenland will be able to support once all the ice is gone? Will we see forests and such?

I know salt water intrusion will devastate much of Louisiana and the Gulf of Mexico region over the next few decades if the trend continues. Far more than what we've seen in the past. Even in the river basins north of Lake Ponchartrain and Maurepas, rising sea levels will easily bring salt water up to 190 and I-12 in several of the river basins by 2100. This will totally destroy much of the forests and other vegetation which lives on these fresh water rivers which are at low elevation and gradient
Techno1
1 / 5 (3) Aug 15, 2011
I know at least two small rivers north of the lakes which are at only about a half foot to a foot above sea level for their current water level, at least when at "normal" or "below normal" water levels.

This means that if the sea level rises by just 6 to 12 inches, the salt water intrusion will already be as far north as i-12 and highway 190, at least in the river basins...

So mean sea level rise will begin to have an effect on vegetation, fisheries, and wildlife, even that far inland, in as little as 6 to 12 inches...

And for reference, 23 feet of sea level rise would put salt water nearly two feet above the "official" record river flood stages in Livingston and Tangipahoa parish, though it's possible the fresh water was higher than that in the 1983, because the river gauges were probably under water...

Now while this may be decades or centuries away from ever happening, it is a terrible thought to think of how drastically that would change America...
TheGhostofOtto1923
3.4 / 5 (5) Aug 15, 2011
If a collosal failure of the entire GLACIER happens, causing a giant tsunami that circles the globe

So I would conclude that this melting is natural, and is not man made, because the rate of increase in melting actually recorded (see article above,) agrees, approximately, with a regression that ignores changes in CO2...

it's clear that if you plotted in terms of 5 year running averages, and if you fit a quadratic regression curve instead of a linear trend, it would show that the rate of annual net melting is accelerating very much...
Uh, QC/Techno, arent you forgetting one small factor? That you have NO IDEA what you are talking about?

S_TF_UP
Techno1
1 / 5 (1) Aug 15, 2011
Uh, QC/Techno, arent you forgetting one small factor? That you have NO IDEA what you are talking about?

S_TF_UP


Hey otto, anybody can calculate the average net change in albedo, based on publicly known solar constant data, and angle of incidence, and ice quality,etc, you idiot.

And once you compare average albedo of Sea Ice being 0.50 to 0.60, and average albedo of sea water being 0.8, then you can find the average change in solar input per meter squared.

But I guess you don't believe in the basic science then, that's fine.

But then you STFU, because you don't know what you're talking about.

And unlike fools such as yourself, once you know what the difference in heat input is due to changes in albedo, it's easy to figure out the maximum increase in the rate of melting of ice.

So go eat it, otto, and quit harrassing me.

You'll see in a few more years how bad the melting is, it may even be worse than I thought, unless something really big happens to stop.
TheGhostofOtto1923
3 / 5 (4) Aug 15, 2011
Hey otto, anybody can calculate the average net change in albedo, based on publicly known solar constant data, and angle of incidence, and ice quality,etc, you idiot.
But only you would think your rambling scribbles can lead to the sort of valid conclusions that scientists take months of work and hours of supercomputer time to reach.

This has been pointed out to you before. Invariably someone comes along and says 'Hey QC you forgot this simple thing... and this, and this one here...'

You have NO IDEA what youre talking about. This is embarrassingly obvious. Shut the hell up.
Techno1
1 / 5 (1) Aug 15, 2011
http://igloo.atmo...;sy=2011

Look at this, idjit.

There is less Ice now in August 13, 2011 than there was in September minimum of 1996.

There is about 1/4th OR LESS as much pink(70% or greater,) and the extent of 30% or more looks to be down by about 25% or so...

We still have at least another 30 days of melting this year.

How low do you think this is going to go this year?

Personally, I think the Pink is going to completely disapear, and the 15% extent and maybe even 30% extents are going to be below the 2007 September minimum.

http://igloo.atmo...;sy=2011

and

http://igloo.atmo...;sy=2011

I wouldn't be surprised if this year's 15% extent minimum beats 2007 by a half-million km, even though it's currently temporarily above the curve again, it's still at least 30 more days melt
Techno1
1 / 5 (1) Aug 15, 2011
This graph was updated YESTERDAY.

http://nsidc.org/...ries.png

If you'll notice, the 2011's 15% extent is parallel to 2007, so it "looks" as if we might have more ice this year, right?

Wrong!

http://igloo.atmo...;sy=2011

Look where the pink and purple (70% to 100% ice) has already gone!

Disappeared, all but a smidgin.

http://igloo.atmo...;sy=2011]http://igloo.atmo...;sy=2011[/url]

September 2007 minimum vs now.

We have less pink now than the minimum then.

We have barely more extent red and green than the pink was then...

The purple (90 to 100%) well, that just flat out disappeared already. We don't even have any purple. It's all gone.

http://igloo.atmo...;sy=2011]http://igloo.atmo...;sy=2011[/url]

This is going to SHOCK everybody. Even republicans and tea party believe after September...
TheGhostofOtto1923
1 / 5 (1) Aug 15, 2011
Disappeared, all but a smidgin.
And why don't you calculate exactly what that smidgeon represents, in 5 or 6 posts, leaving out of course a few (dozen) major factors which you were unaware of because you have no FREAKING idea what you're doing?

Take your time.
Techno1
not rated yet Aug 16, 2011
The new volume of ice data is in.

http://nsidc.org/...ure5.png

Nothing surprising here.

2011 seems to be officially well below 2007 for same day vs same day.

The end of this data plot, 2011 is even very near, or possibly even below the 2007 volume minimum.

the 2011 curve is, by my estimation, around 2100 cubic kilomters less than 2007.

If the trend continues, this means the grand minimum in September will be at or near 5000 cubic kilometers volume.

The heat of melting to melt only the EXTRA ice that melted this year compared to 2007 is 6.93E20 Joules, and neglecting the specific heat capacity of warming sub-zero ice, and of course, neglecting any other "extra" heat that managed to radiate into space or go to other places in the environment, instead of melting arctic sea ice, etc.

Thus, the amount of energy needed to melt only the EXTRA melted ice volume for 2011 vs 2007 is around 136% as much energy as humans use in an year...