Greenland 2012

[TerryM]

Verg

Thanks for the response - I really do intend to dig (drill:) into this over the winter - but things are unraveling so rapidly right now that I begrudge the time it would require.

Albedo over Greenland is rebounding, at least to levels seen in other years thanks to the snowfall. We're leaving the period when insolation is as important (Perhaps Dr. Box will provide a chart that merges insolation and albedo change on a monthly basis,).

An interesting feature has been the salinity change in Fram Strait just off the coast where 79 is draining. It's easiest to visualize using the ARC SSS animation.

The Humboldt still appears to be shedding into Kane Basin - It will be interesting to see where the greatest ice mass losses have occurred. For those interested in the minutia of fast ice and glacial movement, the new high def. split zoom feature at Arctic.io is a must. With the split zoom the slight movement of the not quite fast ice south of Flade Isblink becomes apparent, previously it would be easy to assume that it had remained static.

Terry

[Vergent]

Terry

I do not think that CH4 can have high resolution in the core samples, that is why they only sample every 2 meters. Snow is 90% air, the CH4 is in the air fraction and is mobile. For the hundreds of years, before there is sufficient overburden to turn it to ice, there is diffusion and movement within the column.air from underneath is forced through the snow from below as it is compressed. A short spike would be smeared. The best you could hope for is about a 20 year average value. This would be true for all the gas phase constituents. They get pushed up in the column and get smeared.

It struck me that IA wind patterns could be identified in two ways. First, glacier directions. glaciers form on the windward side so glaciers tend to flow toward the wind. Glaciers in Alaska flow west. Glacier national park, east. Yosemite flows west.

[TerryM]

Verg

The event i was trying to get a handle on was the Storegga Slide - They're showing a carbon date of 6100 BCE, so not too far from my remembered 8K yr. BP - unless they're talking uncalibrated radio carbon years. I'd assume that anything big enough to separate England from the continent would have left it's mark in the cores, but as said, it'll be this winter before I get a chance to try to learn something about these. I'm of the opinion that nobody is capable of learning all there is to know about even relatively simple phenomena, let alone something as complex as Arctic ice melt, but this doesn't mean that we can't try.

Terry

[TerryM]

Spring tide

Spring tides wreak havoc on fast ice, and the earliest example for this one is the fjord north of Flade Isblink. MODIS terra r03c03 has a fairly clear view. The ice offshore of Princess Margareth has fractured and is heading south into the Greenland Sea. I don't know whether this is the same ice that in 1951 was found to have been part of the huge ice shelf that extended out from Ellesmere Island, but it had survived the most recent melt in the area back in 2002.

MYI >14 yrs, possibly >3,000 yrs old - anyway it's gone.

It opens up the flow of the northern glacier draining Flade Isblink as well as making room for more ice advecting through Fram Strait.

Terry

[TerryM]

Not exactly Greenland.

Fast ice and ice shelves are one of the things I find fascinating about the Arctic at this time of year. The demise of the gigantic ice shelf that once stretched from Ellesmere at least as far as Flade Isblink is all but gone, with Ward Hunt getting some publicity last year when it split in two. It's in danger again this year, but so is the ice island remnant west of it.

Milne ice shelf blocks the fjord three fjords west of Hunt Ward, and can be seen as a barbell shape on MODIS r03c03.

The open water in Milne Fjord is new this year, and while it still appears firmly attached at the western and eastern sides at some point it will join Serson, Petersen, Ayles, Ward-Hunt and Markham as entries in obscure history books. In 1986 it had an area of 296 square Kilometers, and is the largest of the remaining shelves since Ward-Hunt bifurcated about a year ago.

I apologize in advance for drifting off topic, and my only excuse is that in my lifetime you could walk from Greenland to Milne Fjord at any time of the year.

Terry

[TerryM]

Just rushed over to Neven's to announce the the calving event at Steensby Glacier - only to find someone beat me to it.

Proof that old men should eshew taking naps in the late afternoon.

Terry

addendum

PII2012 looks to have bypassed all the islands that could have fractured it and will probably exit Nares Strait in one piece.

[TerryM]

The Steensby calving event is noted on Dr. Muenchow's blog site. It's smaller than PII2012, but apparently 2 to 3 times thicker.

http://icyseas.org/2012/06/19/nares-strait-ice-bridge-and-arctic-ice-thickness-change/

Dr. Box , noting that albedo changes are worsening again sees melting continuing in what was already the warmest year recorded on Greenland. Lots of charts & graphs at

http://www.meltfactor.org/blog/?p=514

The predictions that Greenland wouldn't melt for a thousand years are as relevant as those that told us the Arctic ice would be OK for a hundred years.

Terry

[TerryM]

The albedo is still heading south according to Dr Box's charts and Dr Pelto has some wonderful images and insights on the Steensby calving event.

http://glacierchange.wordpress.com/2012/08/25/steensby-glacier-calving-event-and-retreat-northern-greenland/#comment-1355

Terry

[TerryM]

Wondering if the 6.6 earthquake just north of Jan Mayen Island might have spawned a tidal wave. Any clathrates in the area might also be at risk.

We're not quite at spring tide, but if even small tsunami coincided with high tide we should be able to see the damage tomorrow.

Terry

[TerryM]

While attention as been diverted by the calving events at Petermann and Steensby and the changes ion the north east coast, Humboldt Glacier has been steadily shedding small icebergs all through the melt season. Today's MODIS images show a bit more around the "horn", but the ablation has been ongoing.

Humboldt isn't a rapidly advancing Glacier, but the front is so wide that even a little off the end adds to large volumes. It will be interesting to see how Humboldt's losses compare to the more spectacular calving events from other glaciers.

Terry

[TerryM]

PII2012 has broken up on the ice sill in Kane Basin.

Dr Muenchow has all the info at:

http://icyseas.org/2012/09/02/petermann-ice-island-2012-breaking-up/

Together with Ranger images, bathymetry of Nares Strait and an explanation of why and how it happened.

Terry

[tacoman25]

Looks like some pretty cold air is starting to move in over Greenland.

[The_Global_Warmer]

Flade Isblink is in danger of bifurcating, probably not this year, but soon. It had melted out some 3k yrs ago, about the time that the Ellesmere ice shelf melted.

I hope the people that stated that the Greenland ice cap would be around for a thousand years weren't the same ones who said that the polar ice was in no danger of melting out for a hundred.

Anyone still think GRACE will show a recovery this year?

Terry

no. The first product to update during the June and July period. This graph is updated through 2012.6140 or about August 5th-8th. The text data shows from where the other three major SLR sources left off 2012.4500. The sea level dropped(this is a seasonal norm) until 2012.5060 and has risen since about 10MM. The peak isn't until around 2012.7800 to 2012.8000. So late September or so.

This could be one of the largest rises in our satelitte record for one yearly cycle.

A few other factors. SST rise during this time, OHC could of rose but AMJ OHC dropped a bit from the winter, but typical rises more in the summer JAS period. but thermal interia is not the driver, maybe more vapor being put back into the oceans after floods but the big driver is Northern Hemisphere Glacial loss and ENSO. That Green line doesn't update all the way yet, the last three readings(10 day blocks were 41.82, 43.38, 42.34) this is running 12-16MM above of 2011 at this time. 2011 peaked at around 34MM at the end of September on this scale last year. So we will likely see 2012 peak around 50MM on this scale.

Overall it's pretty clear the recent large glacial ice losses are catching up with the SLR rise and obviously as things even out will show a temporary increase at least in sea level rise rates.

ENSO is looking decent for a mild to moderate NINO coming up, this will also push SLR upwards.

monthly sst anomaly's are running 0.275C through August. 2010 peaked at 0.320C, this helps rise SLR too.

[PhillipS]

Dr Jason Box has a new post at meltfactor.org on the Ilullssat, also known as Jakobshavn, glacier and its high discharge rates.

In 2012, this glacier front lost an an area of 13 sq km, measured from August 2011 to August 2012. Thi’s year’s area loss is the largest since the 2007-2008 interval. A concern is that this and other major marine terminating glaciers, as they retreat, they accelerate, increasing their global sea level contribution.

Ilulissat is considered the fastest continuously flowing glacier in the world. But instead of calving massive tabular icebergs like Petermann glacier, Ilulissat calves large numbers of angular bergs. Supposedly the Titanic was sunk by an iceberg from Ilulissat. In terms of sea level, since Ilulissat drains a portion of the Greenland Ice Sheet all of its discharge adds to sea level rise.

[The_Global_Warmer]

Dr Jason Box has a new post at meltfactor.orgon the Ilullssat, also known as Jakobshavn, glacier and its high discharge rates.

In 2012, this glacier front lost an an area of 13 sq km, measured from August 2011 to August 2012. Thi’s year’s area loss is the largest since the 2007-2008 interval. A concern is that this and other major marine terminating glaciers, as they retreat, they accelerate, increasing their global sea level contribution.

Ilulissat is considered the fastest continuously flowing glacier in the world. But instead of calving massive tabular icebergs like Petermann glacier, Ilulissat calves large numbers of angular bergs. Supposedly the Titanic was sunk by an iceberg from Ilulissat. In terms of sea level, since Ilulissat drains a portion of the Greenland Ice Sheet all of its discharge adds to sea level rise.

The arctic region is trending out of control

[PhillipS]

There is a new paper, Wang et al 2012, [source] which presents an analysis of the Greenland Ice Sheet as a material science analysis rather than a climatology analysis. Here is the abstract:

Mass-balance analysis of the Greenland ice sheet based on surface elevation changes observed by the European Remote-sensing Satellite (ERS) (1992–2002) and Ice, Cloud and land Elevation Satellite (ICESat) (2003–07) indicates that the strongly increased mass loss at lower elevations (<2000 m) of the ice sheet, as observed during 2003–07, appears to induce interior ice thinning at higher elevations. In this paper, we perform a perturbation experiment with a three-dimensional anisotropic ice-flow model (AIF model) to investigate this upstream propagation. Observed thinning rates in the regions below 2000m elevation are used as perturbation inputs. The model runs with perturbation for 10 years show that the extensive mass loss at the ice-sheet margins does in fact cause interior thinning on short timescales (i.e. decadal). The modeled pattern of thinning over the ice sheet agrees with the observations, which implies that the strong mass loss since the early 2000s at low elevations has had a dynamic impact on the entire ice sheet. The modeling results also suggest that even if the large mass loss at the margins stopped, the interior ice sheet would continue thinning for 300 years

and would take thousands of years for full dynamic recovery.

I found this paper interesting because I've read for years that the Greenland ice sheet will take a very long time to melt so there is no danger of a catastrophic collapse. This despite the geological record that ice sheets can, and have, at time collapsed catastrophically.

Some of the underlying assumptions of the prediction that it will take thousands of years to melt the Greenland ice sheet are that rapid melting can only occur around the margins, that the summit is too high and cold to melt, and that the melting around the margin will not have much effect on the bulk of the ice sheet. Basically that the ice sheet would remain a monolithic block, slowly melting in a warmer world.

What the study found out is that these assumptions need to be revisited. Melting at the ice sheet margins does affect the interior because the marginal ice buttressed the bulk of the ice sheet and with the melting of the margins interior ice moves towards the margins, thinning the interior and bringing more ice into the zone of rapid melting.

Ice as a material has some properties that favor rapid dynamic response to warming and melting. An important one is that as ice approaches its melting point it loses much of its structural strength. Many of us have seen this characteristic in action when icicles that have hung from eaves for weeks of cold weather snap under their own weight as temperatures rise. Another example is ice on a river - ice thick enough to support an adult when the temps are low can disintegrate when the temps rise a few degrees.

The paper also points out that movement within an ice sheet, and movement of the ice over the underlying surface, generate frictional heat that raises the temperature of the ice. One way to think of this is the potential energy of the ice at the top of the ice sheet gets converted to kinetic energy and then to heat as the ice sheet thins and the surface drops.

The third characteristic of ice that is relevant to this discussion is that the melting point of ice drops under pressure. This isn't true of many materials. The best example of this that comes to mind are ice skates - the pressure of the skate blades on the ice melts a film of water that lubricates the movement of the blades. What is the relationship between pressure and melting point? I found a good phase diagram to illustrate this characteristic [source]:

As you can see, at a pressure of 200 MPa ice melts to liquid at about -20 C. But that's a lot of pressure. 1 bar is equal to 0.1 Mpa. If I've done the math right, the pressure at the bottom of a 2,000 m high sheet of ice is roughly 20 MPa. (please feel to correct me if that value is wrong) - so the melting temp for the basal ice would be about -2 to -4 C. Still pretty cold, but remember that all of the meltwater flowing down the moulins is greater than 0 C. So the meltwater is carrying plenty of energy to carve passages through the basal ice - weakening the foundation of the ice sheet.

It will take a lot more research to quantify all of the dynamic processes in action within the Greenland ice sheet - but I think that there is very little evidence for complacency.

[Msalgado]

My understanding is that the estimates for a long period of melt of the ice sheets in Greenland and Antarctica are simply due to their mass. In order to melt that much ice you need to add a great amount of energy to the system and the amount needed to melt that high mass of ice is going to take an incredibly long time to accumulate.

On the subject of previous catastrophically quick melting of ice sheets - I would ask that you provide some scenarios in the past to compare today's situation to. If the scenarios you are thinking of match up and occur at shorter than centennial time scale then perhaps you will have an analogue to compare. However, if the other situations are different (IE they occurred in a different region - specifically on ice sheets that could quickly enter the ocean) and occurred on much longer time scales then you likely can't draw a parallel.

The last point you make about pressure driven melting forgets that ice melted under higher pressure would refreeze upon pressure loss. This same process is why air that rises over a mountain and has water vapor condense due to pressure loss has that same water return to vapor form when it descends and is re compressed.

[TerryM]

My understanding is that the estimates for a long period of melt of the ice sheets in Greenland and Antarctica are simply due to their mass. In order to melt that much ice you need to add a great amount of energy to the system and the amount needed to melt that high mass of ice is going to take an incredibly long time to accumulate.

On the subject of previous catastrophically quick melting of ice sheets - I would ask that you provide some scenarios in the past to compare today's situation to. If the scenarios you are thinking of match up and occur at shorter than centennial time scale then perhaps you will have an analogue to compare. However, if the other situations are different (IE they occurred in a different region - specifically on ice sheets that could quickly enter the ocean) and occurred on much longer time scales then you likely can't draw a parallel.

The last point you make about pressure driven melting forgets that ice melted under higher pressure would refreeze upon pressure loss. This same process is why air that rises over a mountain and has water vapor condense due to pressure loss has that same water return to vapor form when it descends and is re compressed.

How many Joules have you calculated that the GIS will require for meltout?

Terry

[PhillipS]

My understanding is that the estimates for a long period of melt of the ice sheets in Greenland and Antarctica are simply due to their mass. In order to melt that much ice you need to add a great amount of energy to the system and the amount needed to melt that high mass of ice is going to take an incredibly long time to accumulate.

On the subject of previous catastrophically quick melting of ice sheets - I would ask that you provide some scenarios in the past to compare today's situation to. If the scenarios you are thinking of match up and occur at shorter than centennial time scale then perhaps you will have an analogue to compare. However, if the other situations are different (IE they occurred in a different region - specifically on ice sheets that could quickly enter the ocean) and occurred on much longer time scales then you likely can't draw a parallel.

The last point you make about pressure driven melting forgets that ice melted under higher pressure would refreeze upon pressure loss. This same process is why air that rises over a mountain and has water vapor condense due to pressure loss has that same water return to vapor form when it descends and is re compressed.

Let's look at the energy required first. The USGS says that there is roughly 2.6M km3 of ice in the Greenland ice sheet. We know that annually solar insolation adds enough energy to the Arctic region to melt about 15,000 km3 of sea ice, 500 km3 or more of glacial ice, and a lot of snow on land. For discussion purposes I'll round that to an annual melt of 16,000 km3 of ice. That's enough energy to melt the whole Greenland ice sheet in just 162 years. Of course, most of that energy will continue to melt sea ice - but as the sea ice continues to diminish that fraction will diminish, too. And the albedo shift over land and sea will mean less solar energy will be reflected back into space and more will be retained within the Arctic region, raising temperatures and accelerating the melting of the ice sheet. So sufficient energy to melt the Greenland ice sheet in several centuries is present and will contiue to be present in the future. I don't know of research that gives a firm prediction of how quickly the melt can occur - but to flatly assert that a complete melting of the ice sheet will have to take millenia is just wishful thinking.

You asked for examples - well, two recent examples are teh breakup of the Larsen A ice shelf in January 1995, and the breakup of the Larsen B ice shelf in February 2002. I couldn't find the volume of the Larsen A breakup, but Larsen B was about 650 km3. These were both floating ice shelves rather than land ice sheets but they are relevant to my point about Greenland because their breakups were rapid, unexpected, and were caused by previously unknown ice dynamics.

For an example of a catastrophic failure of a land glacier let's go back (about 15,000 years) to the final days of Lake MIssoula - the glacial lake that was about havle the size of modern Lake Michigan. The ice dam was a finger of the Cordilleran Ice sheet - a big finger about 2,000 feet high and many miles across - so it makes a good analog for the Greenland ice sheet. The glacier dam failed abruptly (several times, actually) causing a series of catastrophic floods that traveled all the way across present Washington state to the Pacific. There is a good introduction to this at the University of Wisconsin website [source]. Here is one of their colorful graphics:

Water beneath and within the ice could have enlarged channels by frictional heating, and erosion by surface drainage could also have eroded the ice front. It's possible that breakup of the ice front might have occurred and jokulhlaups began to pluck away at the terminus.

Your final point - that melted basal ice would refreeze once the pressure is reduced - is just wrong. Once the basal ice has received sufficient latent heat (energy) to melt and has become mixed with meltwater, even meltwater at 0 C, it has too much energy in it to refreeze. It adds to the volume of meltwater flowing under the ice sheet and emerging at the margin. A good example of this was the meltwater flood at Kangerllusuaq, Greenland in July of this year. Jason Box posted links to videos of the flooding on meltfactor.org. We can see that the meltwater is carrying a lot of silt which means that melting basal ice was involved because surface meltwater doesn't have any silt.

[Msalgado]

Let's look at the energy required first. The USGS says that there is roughly 2.6M km3 of ice in the Greenland ice sheet. We know that annually solar insolation adds enough energy to the Arctic region to melt about 15,000 km3 of sea ice, 500 km3 or more of glacial ice, and a lot of snow on land. For discussion purposes I'll round that to an annual melt of 16,000 km3 of ice. That's enough energy to melt the whole Greenland ice sheet in just 162 years. Of course, most of that energy will continue to melt sea ice - but as the sea ice continues to diminish that fraction will diminish, too. And the albedo shift over land and sea will mean less solar energy will be reflected back into space and more will be retained within the Arctic region, raising temperatures and accelerating the melting of the ice sheet. So sufficient energy to melt the Greenland ice sheet in several centuries is present and will contiue to be present in the future. I don't know of research that gives a firm prediction of how quickly the melt can occur - but to flatly assert that a complete melting of the ice sheet will have to take millenia is just wishful thinking.

You asked for examples - well, two recent examples are teh breakup of the Larsen A ice shelf in January 1995, and the breakup of the Larsen B ice shelf in February 2002. I couldn't find the volume of the Larsen A breakup, but Larsen B was about 650 km3. These were both floating ice shelves rather than land ice sheets but they are relevant to my point about Greenland because their breakups were rapid, unexpected, and were caused by previously unknown ice dynamics.

For an example of a catastrophic failure of a land glacier let's go back (about 15,000 years) to the final days of Lake MIssoula - the glacial lake that was about havle the size of modern Lake Michigan. The ice dam was a finger of the Cordilleran Ice sheet - a big finger about 2,000 feet high and many miles across - so it makes a good analog for the Greenland ice sheet. The glacier dam failed abruptly (several times, actually) causing a series of catastrophic floods that traveled all the way across present Washington state to the Pacific. There is a good introduction to this at the University of Wisconsin website [source]. Here is one of their colorful graphics:

Water beneath and within the ice could have enlarged channels by frictional heating, and erosion by surface drainage could also have eroded the ice front. It's possible that breakup of the ice front might have occurred and jokulhlaups began to pluck away at the terminus.

Your final point - that melted basal ice would refreeze once the pressure is reduced - is just wrong. Once the basal ice has received sufficient latent heat (energy) to melt and has become mixed with meltwater, even meltwater at 0 C, it has too much energy in it to refreeze. It adds to the volume of meltwater flowing under the ice sheet and emerging at the margin. A good example of this was the meltwater flood at Kangerllusuaq, Greenland in July of this year. Jason Box posted links to videos of the flooding on meltfactor.org. We can see that the meltwater is carrying a lot of silt which means that melting basal ice was involved because surface meltwater doesn't have any silt.

Thanks for the examples. I don't have the required time right this second to look at them but I'll look them over tonight and respond. I believe I have read on Lake Missolua but my recollection is not very clear at all. If indeed it does make a good analogue for Greenland I would completely agree we should be more concerned. As for the Larsen Ice Shelf I do not think a comparison is a good thing because it was a floating ice shelf and not an ice sheet on land. The access to energy from water is of course much greater.

[Msalgado]

How many Joules have you calculated that the GIS will require for meltout?

Terry

I have not made such calculations. It would be interesting to see if there are any calculations out there for such an event in the peer reviewed literature. I will do some searching tonight and this weekend but if you have any sources I would love to see them.

[PhillipS]

Thanks for the examples. I don't have the required time right this second to look at them but I'll look them over tonight and respond. I believe I have read on Lake Missolua but my recollection is not very clear at all. If indeed it does make a good analogue for Greenland I would completely agree we should be more concerned. As for the Larsen Ice Shelf I do not think a comparison is a good thing because it was a floating ice shelf and not an ice sheet on land. The access to energy from water is of course much greater.

Regarding the Larsen ice shelves - their breakup was attributed to the meltwater ponds on the surface enlarging fissures, not any process involving seawater. There is a good NASA EarthObservatory post which describes the breakup with pics to illustrate the stages.

[TerryM]

The breakup of the Laurentide ice sheet & draining of Lake Agassi are also fairly well documented land based collapses.

It's interesting keeping an eye on the shrinkage of the Barnes ice cap on Baffin island - the last remnant still extent. The lake to the east seems to make inroads each year.

Phillip

A feedback you didn't mention is the increasing longwave radiation from an increasingly opaque atmosphere.

I think we'll see some indications that things have really left the tracks when Flade Isblink bifurcates, then melts out. (it was gone during the Holocene Max) It began to look a little shaky this year as I've posted above. It's the second largest ice cap in Greenland, though much much smaller than the GIS.

Another region I've been watching is the ice field above King Christian IV Fjord, it's not huge, but shows very dark albedo, and would split the mountains to the east from the rest of the cap. It won't go in the next few years, but it's definitely on it's way.

If the Saddle region melts out in the next 4-5 decades, the remaining two caps will be melting from all sides. (Probably not stable)

The above are in the order I'd expect to see happen, unless the ground level measurements are wrong and Atlantic waters can undercut the ice cap, or if the bottom is rubble that can be channeled through by melt water and ice.

If that happens things accelerate significantly.

Terry

[Jonger]

I guess Greenland interior hit -30C last night.

Record low.

Sent from my ADR6425LVW 2

[SVT450R]

Summit is sitting at -42F atm did a quick look back on weather underground stats only go back to 04 the earliest below -40f reading was on 9/15/04 which was -42f.

[Jonger]

Summit is sitting at -42F atm did a quick look back on weather underground stats only go back to 04 the earliest below -40f reading was on 9/15/04 which was -42f.

Greenland summit to Terry: "Cool story Bro"

[The_Global_Warmer]

Greenland summit to Terry: "Cool story Bro"

I guess Greenland interior hit -30C last night.

Record low.

Sent from my ADR6425LVW 2

No, it's just meaningless. Terry is older and isn't going to address how this doesn't matter.

early September Greenland ice reflectivity remains low, some melting remains active

September 7th, 2012

While ice sheet average temperatures are declining with the return of the cold season this September, ice sheet reflectivity (a.k.a. albedo) remains anomalously low (Fig. 1). The low albedo values reflect (pun alert) where snow accumulation has not yet covered the darkened surface. There remain some areas where melting remains active at the lowest elevations of the ice sheet (Fig. 2). Melt promotes or maintains low ice reflectivity. Available sunlight in 2012 thus continues to heat the ice and snowpack more than it has in the period of observations beginning in 2000. Less heat will be required to maintain melting or bring the ice to the melting point in the future. It is easy to predict early melt onset in 2013 and a continuation of increasing ice sheet melt rates that contribute to the recently observed net ice loss from Greenland.

The Summit can be -40F this early and set record lows under domes of high pressure with that sinking air sloping down the ice sheet. The perfect radiational cooling box for the summit and most of Greenland. On the 3rd which was 6 days ago now most of the ice sheet was still below normal in reflectivity, of course only the darkest purple/blue area's are still warm enough for melt.

The summit is 10.5K feet above sea level, or at 700mb that is pretty high up.

On Modis we can see melting is still taking place, with warm air sweeping in as I type.

http://en.wikipedia.org/wiki/Summit_Camp The September average low -35C.

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?mosaic=Arctic.2012253.terra.1km

[Jonger]

No, it's just meaningless. Terry is older and isn't going to address how this doesn't matter.

The Summit can be -40F this early and set record lows under domes of high pressure with that sinking air sloping down the ice sheet. The perfect radiational cooling box for the summit and most of Greenland. On the 3rd which was 6 days ago now most of the ice sheet was still below normal in reflectivity, of course only the darkest purple/blue area's are still warm enough for melt.

The summit is 10.5K feet above sea level, or at 700mb that is pretty high up.

On Modis we can see melting is still taking place, with warm air sweeping in as I type.

http://en.wikipedia....ummit_Camp��The September average low -35C.

http://lance-modis.e...12253.terra.1km

September average low? I would assume that figures in the entire month and not the 8th of the month. The average low is pretty flat in "Barrow, AK" during the entire summer and doesn't start moving down much until the 2nd week of September. This was probably 20 degrees below normal, not the most impressive figure, but interesting.

[The_Global_Warmer]

September average low? I would assume that figures in the entire month and not the 8th of the month. The average low is pretty flat in "Barrow, AK" during the entire summer and doesn't start moving down much until the 2nd week of September. This was probably 20 degrees below normal, not the most impressive figure, but interesting.

Dude, Barrow Alaska is 10 Feet above Sea Level and at 71N. Summit Camp is 10,551 Feet above Sea Level sitting at 72N, not to mention on top of a gigantic Ice sheet with recently freshly fallen snow, infact it always has snow, that typically never even melts.

The average low in August is -23C, in July -20C, June -21C. So saying it was 20 degrees below normal means you didn't read the link I sent you.

NOAA/ESRL has September 9th average temp at -16C for 700mb and that station is slightly above that and again is a massive ice sheet with snow on top. Meaning the little solar energy left 85% is being sent back into space, it's a losing proposition for a place like that.

Dec-Feb average lows there are -69C, -72C, -63C. It's amazingly cold, if it was another 5000ft up it would be just crazy to see the kind of cold that would show up there.

I am seriously sorry for constantly sounding like I am harping. Just do a bit of research. I assure you myself and my gang of "warminists" are pretty bright people who care deeply about humanity, life, and the fragile system that we need to keep as un-disrupted as possible if we are going to ascend in the future. Most of us do independent research, end up realizing what is happening, end up collaborating with like minded people, also argue with similar minded people for checks and balances it's not like we come here making up real time science which in turns leads to speculation and prediction that happens to show us being side screwed as many ways as we could be from this.

[Jonger]

I'm not arguing Barrow being similar in temp to the Greenland summit. I'm only saying that the average low temps in the arctic are only starting to decline.