Greenland 2012

[The_Global_Warmer]

http://www.meltfactor.org/blog/

[PhillipS]

Just not at the shoreline............

Oddly enough, if one were to speculate in Greenland real estate today's shoreline is exactly where you should look if you want 'beachfront' property after the ice sheet melts. The reason for this is that as the Greenland ice sheet melts the sea level around Greenland will drop by tens of meters. Counter-intuitive, right? I confess it was for me.

There are two major processes that act to lower sea levels around Greenland. The first is the gravitational attraction of the mass of the ice sheet. The ice sheet has a huge mass and that mass pulls a 'bulge' of seawater closer to Greenland's shores. How big is that bulge? Well, the volume of the Greenland ice sheet is about 2.6M km3, the specific gravity of ice is about 0.9, so an comparable mass of seawater would be roughly 2M km3. Distributed around Greenland that volume elevates the shoreline sea level by many meters. As the ice sheet melts, the gravitational attraction lessens and the shoreline recedes as a corresponding amount of seawater dissipates.

Here is a good video by

of Harvard that discusses this phenomenon. The whole video is well worth watching, but the portion on Greenland's ice sheet starts about 12:45 into the talk. We generally think of sea level in terms of the 'bathtub model' with sea levels being at the same height everywhere, but we've known for a long time that reality is more complicated than that. Greenland is one example of where sea level isn't level after all.

The second process that will lower Greenland's sea level is isostatic rebound. The mass of the ice sheet is so great that it has depressed the Earth's crust under Greenland and as the ice sheet melts the Earth's surface will rebound. I think we're all familiar enough with this effect that there's no debate about it.

If you decide to speculate in Greenland real estate please leep us updated on how that turns out.

[TerryM]

Beautifully clear images of Nares Strait on MODIS today. We can hope that the MYI now north of Hall Basin stays in place until Dr Muenchow is safely back in Thule.

The increasing flow through Fram Strait has effectively sealed off Independence Fiord, but it's still far ahead of where it was last year at this time & I'm sure it will open this year.

My own pet project of King Christian IV Glacier hasn't done a lot, but the darkness of the ice and melt ponds don't bode well for the future.

Summit highs were -2C - very warm, but not enough for another complete melt. Max temp for Greenland was up to 20C again in the last 24 hours and baring an Icelandic Volcano I can't imagine this year not breaking all previous melt records.

Terry

[The_Global_Warmer]

Beautifully clear images of Nares Strait on MODIS today. We can hope that the MYI now north of Hall Basin stays in place until Dr Muenchow is safely back in Thule.

The increasing flow through Fram Strait has effectively sealed off Independence Fiord, but it's still far ahead of where it was last year at this time & I'm sure it will open this year.

My own pet project of King Christian IV Glacier hasn't done a lot, but the darkness of the ice and melt ponds don't bode well for the future.

Summit highs were -2C - very warm, but not enough for another complete melt. Max temp for Greenland was up to 20C again in the last 24 hours and baring an Icelandic Volcano I can't imagine this year not breaking all previous melt records.

Terry

Sea Levels through April didn't take the normal decline. of course they dropped for seasonal variation. The peak is typically September. So we will see how it reacts this year, if there is a real noticeable difference. 720Gt = 2MM, 1080GT = 3MM.

We will in my guess loss 750-900 GT of ice this year in Greenland, just summer loss not total net from the warm and cool seasons.

[TerryM]

Meltfactor is reporting that albedo below 1,500M (5,000 ft.) is at its lowest for the year - and since recording began. The melt continues.

Terry

[The_Global_Warmer]

Terry, this is truly an epic happening. Just imagine how much more ice is melting this year than 2010 and 2011. We might end up 10-15x higher than the 2000-2011 seasonal average which I believe is in the 50-70GT range. However I believe we top this within 3 years. because albedo issues will not just go away.

[Jonger]

Terry, this is truly an epic happening. Just imagine how much more ice is melting this year than 2010 and 2011. We might end up 10-15x higher than the 2000-2011 seasonal average which I believe is in the 50-70GT range. However I believe we top this within 3 years. because albedo issues will not just go away.

Something new had to be introduced to the snow cover. This is just too much of a sudden change. I wonder if there was a layer of ash that finally got exposed.

[SVT450R]

Aerial Photos Reveal Dynamic Greenland Ice Sheet: Ice Sheet Has Recently Retreated Then Restabilized

http://www.sciencedaily.com/releases/2012/08/120802141523.htm

[bluewave]

You can track the Arctic/Greenland warming over recent Julys.

[TerryM]

Aerial Photos Reveal Dynamic Greenland Ice Sheet: Ice Sheet Has Recently Retreated Then Restabilized

http://www.scienceda...20802141523.htm

Ice on the west coast of Greenland is effected by flow through Fram Strait. Through the 1980 and 90's there was a huge loss of ice. As Fram increased, ice again built against the coast that is only now melting back - but this time it's melting even with strong advection through Fram.

One of the areas I'm interested in is Independence Fjord north of Flade Isblink. It was open in 2002, last year and opened sometime last night if I'm seeing through the clouds properly. There's been a lot written about ice loss further down the coast, but much of this is simply getting back to 1990's levels.

Today's MODIS is showing a plume of ice in Kane Basin from near the horn of the Humboldt Glacier. I know this thing is grounded, but with recent rains in the area I'd expect volume loss.

What has changed is the albedo across the whole ice sheet, and the only thing that will reverse this is snowfall that makes it through the summer. It will happen at the highest elevations, but probably not further down the slope. A few days ago it was mentioned that this could be the 2007 for Greenland - I couldn't agree more. Skier pointed me to a graph of particulate matter in the atmosphere that peeked in the 50's. I think what has happened is that we've melted through the succeeding 60 years of relatively less ash and soot, and are uncovering the really dirty layers beneath. The stuff is cumulative so the exposed surface is darker with each melt.

When the figures come out for this year I think we'll find that Friv has nailed it - massive ice loss dwarfing 2010.

Terry

[TerryM]

On another blog it's been reported that Ryder Glacier calved earlier this month. I don't think that is correct as the MODIS image from 09/03/2011 seems to show it just as it is.

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r03c03.2011246.terra.250m

and for yesterday

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r03c03.2011246.terra.250m

Rutgers shows this July to be the lowest for NH snow since they began monitoring it in 1967

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r03c03.2011246.terra.250m

which isn't too surprising. The heavy rains in Greenland in the past few days can't be helping the albedo, and things are a little too cloudy today to make out many details.

The Flade Isblink ice cap seems to have shrunk back some in the last few years. It had melted off completely during the Holocene Thermal Maximum 6-8K yrs ago, with temperatures not unlike those we're now experiencing. Might be something to keep an eye on going forward.

Terry

[PhillipS]

Dr Jason Box and his colleagues had a new research paper coming out at the AGU conference. The abstract is at meltfactor.org, and here is an excerpt:

Greenland ice sheet mass loss has accelerated responding to combined glacier discharge and surface melt water runoff increases. During summer, absorbed solar energy, modulated at the surface primarily by albedo, is the dominant factor governing surface melt variability in the ablation area. NASA MODIS data spanning 13 summers (2000 – 2012), indicate that mid-summer (July) ice sheet albedo declined by 0.064 from a value of 0.752 in the early 2000s. The ice sheet accordingly absorbed 100 EJ more solar energy for the month of July in 2012 than in the early 2000s. This additional energy flux during summer doubled melt rates in the ice sheet ablation area during the observation period.

Abnormally strong anticyclonic circulation, associated with a persistent summer North Atlantic Oscillation extreme 2007-2012, enabled 3 amplifying mechanisms to maximize the albedo feedback: 1) increased warm (south) air advection along the western ice sheet increased surface sensible heating that in turn enhanced snow grain metamorphic rates, further reducing albedo; 2) increased surface downward shortwave flux, leading to more surface heating and further albedo reduction; and 3) reduced snowfall rates sustained low albedo, maximizing surface solar heating, progressively lowering albedo over multiple years. The summer net infrared and solar radiation for the high elevation accumulation area reached positive values during this period, contributing to an abrupt melt area increase in 2012.

A number of factors make it reasonable to expect more melt episodes covering 100% of the ice sheet area in coming years: 1) the past 13 y of increasing surface air temperatures have eroded snowpack ‘cold content’, preconditioning the ice sheet for earlier melt onset. Less heat is required to bring the surface to melting; 2) Greenland temperatures, have lagged the N Hemisphere average in the 2000s, need to increase further for Greenland to be in phase with the N Hemisphere average. 3) Arctic amplification of enhanced greenhouse warming is driven by albedo feedback over sea ice, terrestrial environments, and through autumn-winter heat release from open water areas. Likely melt area increases is despite a second order negative feedback operating in the accumulation area identified statistically from more summer snowfall (brightening effect) in anomalously warm summers. Without this negative feedback, the accumulation area complete surface melting may have happened sooner than in 2012.

For any readers not familiar with Dr Box or his work, there is a trove of good information at the meltfactor.org website.

[TerryM]

Behind PII-2012

Dr. Muenchow aboard the Henry Larsen has just spent a day in Petermann Fjord, between the new ice island and the face of the glacier. It's the first ship into Petermann Fjord since the 2010 calving event.

Follow his adventure at

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

In successfully retrieving his instruments from a previous expedition he's poised to add hugely to our understanding to the currents in Nares Strait, and I think all will find his writings and those of others in his party to be riveting.

They also plan to set up a weather station on Joe Island - named for the Inuit who along with Han (with another island named for him) kept an abandoned party alive until they drifted far enough south to be rescued. With Weather stations on Joe and Han islands conditions in Nares Strait can be measured rather than estimated.

Terry

[TerryM]

The high pressure and low temperatures over central Greenland increase the chances of Katabatic winds or Piteraq as they are locally known. These fast moving cold winds aren't usually picked up by weather stations as they follow the lowest valleys to the coast. Similar to the Santa Anna winds in Southern California you can be standing in a ravine and almost be blown over, or move up the slope a short distance and find calm weather.

I fancy that I can see the effects when ice suddenly moves offshore, as it is be doing now in the Cape Morris Jessup area. Recent movements may have more to do with south westerlies coming from the west coast however.

Independence Fjord has opened significantly earlier than last year & the MYI off Princess Margrethe's Island has had a bite taken out. In 2002 the Fjord was open, but this MYI had survived. If a strong Piteraq does hit the area, this could join the floe through Fram Strait and one more ice shelf will be relegated to the history books.

If you aren't following Dr Muenchows adventures you're doing yourself a disservice ( the link is above). He and the team all appear to be accomplished writers as well as researchers.

Nothing new from Dr Box, but I'd expect an albedo update soon.

Terry

[Snow_Miser]

From my point of view, there are three are three contributing factors that pop into my mind that could have contributed to the Greenland Albedo decline.

1) As Jonger had previously said, melting snow could have exposed an area of dust/black carbon from the disgustingly polluted 1960s which may have accelerated ice and snow decline in Greenland.

2) We have had a -NAO for most of the summer, and are forecasted to go more negative, which surges warmth into Greenland:

3) The amazingly warm SSTs near Greenland.

[TerryM]

Snowlover

Interestingly, comparing your NAO charts and Box's albedo charts, the albedo drops off just when the NAO is seen to rise to normal levels. Seems counter intuitive.

Terry

[Snow_Miser]

Snowlover

Interestingly, comparing your NAO charts and Box's albedo charts, the albedo drops off just when the NAO is seen to rise to normal levels. Seems counter intuitive.

Terry

The NAO remaining at low levels throughout the summer is key, not daily fluctuations in the NAO.

[The_Global_Warmer]

The NAO remaining at low levels throughout the summer is key, not daily fluctuations in the NAO.

There is no doubt the NAO helps but there is definitely a much larger role player taking shape. Now the NAO being negative this much might have a large accumulative effect on reaching the dirty layer that has taken the melt through albedo to a whole new level.

2008 NAO index for May, June, and July.

-1.55 -1.09 -1.24

2009 NAO index for MJJ:

1.61 -0.91 -2.11

2010: NAO index for MJJ:

-1.33 -0.52 -0.39

2011: NAO index for MJJ

-0.01 -0.98 -1.48

2012 NAO index for MJJ:

-0.79 -2.25 -1.29

Now the problem is, it's just about impossible to prevent Greenland from having low 2012 like albedo for about half the sheet even under way more ideal conditions for a summer.

And if we have a couple more 2012's, then we might see something epic.

[left_gulley]

The record for the most melt in one season has already been set in Greenland, with four weeks or so of melting still to go.

http://neven1.typepad.com/blog/2012/08/greenland-melting-breaks-record-4-weeks-early.html

[TerryM]

Dr Box's albedo charts have been updated and indicate the recent cold temperatures and snowfall have brought the albedo back up t0 2011 levels, still a standard deviation below normal, but much improved when compared to the July numbers. The ice core samples indicate that we're experienced the warmest summer in Greenland since at least 1150AD - an 862 year record.

At another blog a major calving of Glacier 79 has been announced - I can't find evidence of this due ti the cloud cover. If it happened it's a big deal, but I don't think it did from what I've seen (however the poster accesses images that I don't.)

It will be interesting to see the final melt figures after the huge albedo drops so close to the solstice.

http://www.meltfactor.org/blog/?p=725

Terry

[TerryM]

The record for the most melt in one season has already been set in Greenland, with four weeks or so of melting still to go.

http://neven1.typepa...eeks-early.html

Sorry about the cross post - I hadn't caught this yet at Nevens - Breaking yearly records this early has to be unprecedented - WOW

Terry

[Jonger]

Dr Box's albedo charts have been updated and indicate the recent cold temperatures and snowfall have brought the albedo back up t0 2011 levels, still a standard deviation below normal, but much improved when compared to the July numbers. The ice core samples indicate that we're experienced the warmest summer in Greenland since at least 1150AD - an 862 year record.

At another blog a major calving of Glacier 79 has been announced - I can't find evidence of this due ti the cloud cover. If it happened it's a big deal, but I don't think it did from what I've seen (however the poster accesses images that I don't.)

It will be interesting to see the final melt figures after the huge albedo drops so close to the solstice.

http://www.meltfactor.org/blog/?p=725

Terry

With the buildup of carbon from made mad sources, it might be tough to ever get albedo back to previous levels. We need a volcano to bring well below normal temps in order to glaciate some thick snow/ice over the soot.

[A-L-E-K]

Oddly enough, if one were to speculate in Greenland real estate today's shoreline is exactly where you should look if you want 'beachfront' property after the ice sheet melts. The reason for this is that as the Greenland ice sheet melts the sea level around Greenland will drop by tens of meters. Counter-intuitive, right? I confess it was for me.

There are two major processes that act to lower sea levels around Greenland. The first is the gravitational attraction of the mass of the ice sheet. The ice sheet has a huge mass and that mass pulls a 'bulge' of seawater closer to Greenland's shores. How big is that bulge? Well, the volume of the Greenland ice sheet is about 2.6M km3, the specific gravity of ice is about 0.9, so an comparable mass of seawater would be roughly 2M km3. Distributed around Greenland that volume elevates the shoreline sea level by many meters. As the ice sheet melts, the gravitational attraction lessens and the shoreline recedes as a corresponding amount of seawater dissipates.

Here is a good video by

of Harvard that discusses this phenomenon. The whole video is well worth watching, but the portion on Greenland's ice sheet starts about 12:45 into the talk. We generally think of sea level in terms of the 'bathtub model' with sea levels being at the same height everywhere, but we've known for a long time that reality is more complicated than that. Greenland is one example of where sea level isn't level after all.

The second process that will lower Greenland's sea level is isostatic rebound. The mass of the ice sheet is so great that it has depressed the Earth's crust under Greenland and as the ice sheet melts the Earth's surface will rebound. I think we're all familiar enough with this effect that there's no debate about it.

If you decide to speculate in Greenland real estate please leep us updated on how that turns out.

This was a fun and informative video, thanks

[TerryM]

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

[Vergent]

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

Terry,

Have you looked at the ice core data for sodium, from the end of the last inter glacial? I found quite a bit of relief there.

Sodium is the proxy for wind.

http://www.ncdc.noaa.gov/paleo/icecore.html

Also, we had assumed that current levels were the highest in recent geo past. But isn't the 20th century being erased from Greenland? A clathrate bomb with a significant forcing would easily erase itself with its feed backs, wouldn't it?

Verg(:-)

[Vergent]

Sorry,

forgot how that site wasn't easy to navigate.

ftp://ftp.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/gisp2/chem/iond.txt

Verg

[TerryM]

Sorry,

forgot how that site wasn't easy to navigate.

ftp://ftp.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/gisp2/chem/iond.txt

Verg

Thanks for the new link - the last one had left me wondering.

I thought I'd spend some time this winter trying to make sense of all the core sample data. Some of the findings that I've come across weren't what I would have surmised and I'm curious as to how the northern cores differ from those from Summit and the Saddle. Flade Isblink, while not cored down to bedrock, might have a surprise or two also.

Things have been happening too fast this year to keep up with, let alone trying to get up to speed in a related field.

Do you happen to be aware of any CH4 spikes present about 8k BP? There was that huge clathrate blow out off the continental shelf out from Norway & it would be interesting to know if they have an exact date. A friend does cores of varved lake sediments here in Ontario, and I'm intrigued by the precision of the dating that he gets. He once located the site of a large Iroquoian village after identifying pollen from a weed that's uniquely found in corn fields - the core also showed pollen from portulaca that predated European contact. Prior to his find it was assumed that this was a European weed introduced sometime after Columbus.

Terry

[Vergent]

Terry

Interesting questions. I'll reply later. Do you know when that core data I linked you to became available as a continuous data set? As I recall it came out in frustratingly short bits and pieces.

Verg

[TerryM]

Petermann Ice Island 2012

PII2012 has managed to escape the Hall Basin Gyre and is now past Joe Island - the island that broke PII 2010 in two. It's now into Kennedy Channel and the area that Dr. Muenchow was in just days ago recovering his data recorders. Unless it gets hooked on Han island it will probably leave Nares Strait in one piece.

Dr. Muenchow has the first helicopter photos of the new island at his blog site,

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

as well as the first photo of the new face of Petermann Glacier.

Terry

[Vergent]

Thanks for the new link - the last one had left me wondering.

I thought I'd spend some time this winter trying to make sense of all the core sample data. Some of the findings that I've come across weren't what I would have surmised and I'm curious as to how the northern cores differ from those from Summit and the Saddle. Flade Isblink, while not cored down to bedrock, might have a surprise or two also.

Things have been happening too fast this year to keep up with, let alone trying to get up to speed in a related field.

Do you happen to be aware of any CH4 spikes present about 8k BP? There was that huge clathrate blow out off the continental shelf out from Norway & it would be interesting to know if they have an exact date. A friend does cores of varved lake sediments here in Ontario, and I'm intrigued by the precision of the dating that he gets. He once located the site of a large Iroquoian village after identifying pollen from a weed that's uniquely found in corn fields - the core also showed pollen from portulaca that predated European contact. Prior to his find it was assumed that this was a European weed introduced sometime after Columbus.

Terry

ftp://ftp.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/gisp2/gases/gisp2-8200-gas-iso.txt

m yrs B1950 ch4

1372.025 7715.6 641.0 635.8 646.1

1374.025 7732.0 615.2 625.5 604.8

1376.475 7752.9 628.6 612.5 644.7

1378.025 7766.4 637.1 626.4 647.8

1380.415 7790.4 643.8 649.4 638.1

1382.075 7804.4 638.0 618.5 657.4

1384.025 7821.9 647.0 632.3 661.7

1386.025 7838.6 628.3 624.5 632.1

1388.025 7856.0 629.7 625.4 633.9

1390.025 7874.0 659.2 653.3 665.1

1392.025 7890.9 656.7 650.7 662.7

1394.025 7912.9 654.8 637.1 672.5

1396.025 7934.4 657.2 663.6 650.7

1398.025 7955.5 637.6 640.7 634.4

1402.025 7998.2 650.4 638.8 662.0

1404.025 8020.8 643.9 643.7 644.1

1406.025 8041.5 635.2 629.8 640.6

1408.025 8065.9 608.5 595.7 621.4

1410.03 8091.6 602.3 590.5 614.0

1410.53 8097.7 581.1 578.4 583.8

1411.14 8105.3 576.7 575.7 577.7

1411.53 8110.2 598.9 589.4 608.3

1412.03 8116.3 573.1 568.0 578.1

1412.53 8121.8 575.7 574.6 576.8

1413.03 8127.4 584.4 587.7 581.1

They do not show a methane spike, but they sample every 2m so a 50gt event could be hiding. But I think there is a melt between 7998 and 7955. They skipped an extra two meters for a reason. Or, maybe they got really off the wall values and thru the data out like they do with the flasks. There is a general rise at that time maybe it was a slow process.

Verg

p.s. you have mail