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Paradoxnl.wordpress.com

Neven,

Again a nice overview!

Apocalypse4Real

Neven,

A very excellent summary.

We can anticipate continued heat over the Canadian Arctic and the Arctic Basin in the next 5-10 days. Forecasted temps in the Canadian Arctic are well above freezing at numerous reporting stations.

The midnight 4 July Koeln max temp map showed no areas below freezing in the Arctic - including Greenland.

Alberto Silva

It seems like a Dipole Anomaly will be forming in the next 7 days:

http://policlimate.com/weather/current/gfs_mslp_nh.html

Given how thin has become the ice in Laptev/East Siberian Sea according to the US Navy model (see here) a big dip in ice area and extent is imminent.

This "forecast" will of course be not accurate if the NCEP GFS weather forecast and US Navy HYCOM ice thickness model are not.

FrankD

One slight problem with the piggybank concept is that you get paid interest when you take out a loan. Any region where ice area is low early gets paid a heat dividend as the dark ocean soaks up more heat - rather than an advance reducing the ability to melt ice later, it increases it.

In Baffin Bay, the extent of open water has soaked up vast amounts of heat compared to previous years due to albedo flip. As Nares opens up to transport, the ice entering BB will first have to cool the water down to ~0 before it can survive long enough to increase area (pay back the loan, as it were). I don't expect the CT area anomaly to get back to zero before the third week in August (when the 30-year average area reaches close to 0). And if Hudson Bay over the last couple of years is any guide, one would expect a later than average freeze up in Baffin Bay this year.

OTOH, my guess is that the Greenland Sea will remain relatively high despite high temperatures. The general CT concentration map shows a rather disturbing picture of much of what remains of a consolidated icecap (say 90%+ concentration) being pushed eastwards towards the Fram Strait. Should that continue, most of the best ice in the Arctic Basin will get punted out into the Greenland Sea where the high SST's will eventually melt it. That would keep SIA in this section quite high, while at the same time being disastrous for the state of the icecap generally.

Seke Rob

Some regions will be banking heat for current and next years, but others I'd not estimate to add much to next years, based on their predominant currents. Baffin is a major water outlet, Fram / Greenland Sea is too. That banking and [deplorable] dividends, compound interest come in places as Hudson.

Rob Dekker

FrankD, I hear you.
But it seems to me that the divident on the loan only applied to areas in direct connection with an ample supply of more ice, such as the Kara and the Laptev and the East Siberian (in short, the entire Siberian coast), which seem to be the main drivers of the 2012 extreme decline. And Neven kind of explicitly excluded these areas from the piggy bank for that very reason.

As for my own assessment, take Hudson and the Greenland Sea and Baffin Bay, then w.r.t. the long term average, there is actually a deficit of some 500 k km^2, and w.r.t. 2011, Hudson and Greenland Sea are almost identical, and Baffin Bay shows a 100 k km^2 deficit.
Not much of a piggy-bank there....

I think the eyes should be on the Chukchi, which has been holding back significantly (some 150 k km^2, presumably due to the cold winter), although not as much as the 'satellite record' cold would have suggested.

Either way, by albedo effect or otherwise, the Chukchi will probably melt away to recent levels by September, and thus may be the biggest piggy-bank in town...

I'm very much looking forward to Neven's post on that area.

Rob Dekker

FrankD, on second thought, maybe I misunderstood your post (on divident on the loan) and we essentially mean the same thing. If so, the piggy-bank is close to empty by now.

Rob Dekker

Alberto, I'm not sure if the dipole will actually form, but that wide-spread-out high North of Greenland seems to have some effect : The ice is moving in clockwise direction, causing reduction in the Beaufort and compaction in the central basin.

As for ice thickness plots, I agree that Hycom is far from ideal (in fact is it shown to be way off on many occasions) and we all would much prefer an Arctic-wide plot of PIOMAS on a day-to-day basis.

RunInCircles

Let me throw this out there and ask the community to help me refine this prediction. For ice that is more than 250 Km from the ice edge the melt for the entire month of July is about 0.75 meters. August and Sept about 0.5 meters. Interpreting the Navy thickness graph as being the maximum thickness and assuming average thickness is 0.5 times what is shown I still come to the following conclusions. The ice north of Alaska barely reaches the 75degree line all the way to the mid Chukchi. The ice north of Eastern Siberia melts all the way to the 80degree line. Any ice west of the New Siberian Islands to Greenland melts to the 85degree line. What do the rest of you think?

Werther

RIC,
What you describe fits well into the Central Arctic Basin and would reach about 3.1MK, that is, for extent minimum.
When I remember correctly (skip the 50 m SwissCamp downfall...) I voted on 3.7MK.
I expected the downfall through june, so I'm sticking with my vote.
I'm going to have a look at the Navy graph, please give the correct link...

RunInCircles

Werther
The bottom row of Neven's graph page right in the center. Just roughly I get a lower limit of 3.8MK extent from my prediction.

Neven

I'm very much looking forward to Neven's post on that area.

I was planning on posting it today, Rob, but due to thunderstorms my internet connection is dead (I'm on the town square right now which has free WLAN). Should be fixed by Friday.

What the post will be about basically is that I think 'thick' MYI that has been transported there will be a strong enough barrier to stop the melting, just like we saw in 2010 (The Arm) and 2011. Especially because the water in the Bering Sea and North Pacific seems cold.

Espen Olsen

Scoresby Sund in East Greenland, the world's longest fjord, 350 km long. Will soon be open for traffic in max a week!

R. Gates

Nice analysis Neven. 2012, 2011, and 2007 have really tightened up at this critical juncture. Several things that favor 2012 staying in the lead over the next few weeks:

1) Overall thickness is much lower now than in 2007, and areas
Like the Kara, Barants , and East Siberian have had less ice earlier with more SW penetration leading to warmer water. MYI diverging into these lower latitudes later this summer from the Arctic basin is going to melt quickly, continuing the overall downward trend of MYI in the Arctic. We are going to see some sharp downward spikes now in PIOMAS later this summer and fall.

2. We've seen a record low CAPIE for this time of year. Lots more melt ponding means more SW penetration is occurring closer to the Arctic basin. This of course is a continuation of the "rotting" ice phenomenon as those areas of melt ponds that don't diverge and melt out completely will freeze back into the Swiss-cheese like rotten ice that David Barber so accurately described a few years back.

3. The next few weeks weather with a low AO index is favorable to higher melt rates.

I will be curious to see your analysis of the cooler Bering sea and its impact on the final summer low. My thoughts are that this will only be factor if that is the direction that a large mass of the MYI heads. A strong dipole will push the MYI toward the very warm Atlantic side where it will be eaten up quickly as discussed above, and the temps of the Bering and western side will not be big factors.

Glacierchange.wordpress.com

A glacier at the southern tip of Svalbard, the Olsokbreen has accelerated in its retreat, retreating over 1 km in the last 10 years. Because it has a calving front it should very susceptible to warm ocean water.

Rlkittiwake

Can I make a request of the ice genie?

I really love this graph:

http://i1255.photobucket.com/albums/hh640/drtskoul/MASIE-Day-152-Update-NewFormat.png

Can the Central Arctic be moved to the bottom and the areas that have already melted moved to the top?

Thanks.

michael sweet

GlacierChange:

When the glacial lakes drain they must be 0C. Any part of the glacier they drain through must also be 0C. Is much of the lower part of the ice cap on Greenland 0C? If lakes are appearing higher on the cap does that mean the 0C area is increasing? How far up through the ice thickness is the temperature near 0C? Can you give me a reference for this information so I can learn more? I know that measurements of the ice temperature in cores is used to estimate past climate so the entire ice sheet must have complex temperature gradients.

Thanks.

ThE SnYpEr AzZ

When the Greenland lakes drain, some of the water makes its way to the oceans, while some descends through the ice sheet and refreezes. I believe that experiments have been done by researchers putting instruments and/or substances into moulins. Have any results been published as to what percentage of meltwater reaches the sea ? I believe this could be an important parameter as the number and size of lakes steadily increases.

Glacierchange.wordpress.com

The ice of Jakobshavn below the surface is quite cold. Take a look at page 54 of this Danish Glaciology work that I have utilized. More recently there is work from uwashington. Both indicate how cold the ice. Nonetheless very little of the meltwater leaving the lakes, given its large volume and velocity refreezes.

michael sweet

Glacierchange,
Thank you for the interesting references. I do not understand how water can flow through the glacier without either warming the glacier to 0C or freezing. It must have something to do with the large volumes and flow rates. Not having worked in Greenland it is hard to imagine the scale of the ice sheet.

Good luck on your survey trip this year. I look forward to hearing your reports. I hear they got a lot of snow in the Cascades this year. Hopefully some of it is still left.

Chris Biscan

All of the global models and ensembles are absolutely brutal on the arctic the next 2 weeks.

I do not agree that the Chukchi Ice is safe at all. It's all going to melt if this pattern doesn't stop.

That's a guarentee, if the EURO or GFS verify for the next 10 days. July 14th the Pacific side will be completely falling apart.

11-12C ssts are showing up in the Beaufort along the coast.


Day 179:

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r05c02.2012179.aqua.1km

Day 186:

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r05c02.2012186.aqua


that is ridiculous.

http://www.whoi.edu/page.do?pid=75657


That buoy is smack dab in the Chukchi Sea.

you can see how much heat is under the ice. that is stupid. You can also see how quickly the ice is warming through MYI because there is a lot of FYI or 2YI now that is .50 to 2 meters all over that is being roasted and hurting the overall region.


The Euro and GFS are hinting at 90F being reached along the Siberian Arctic coast as winds blow a large area of 15-20C 850s into the arctic. with an even larger area of 10-20C.

This is just stupid warm.


DrTskoul

Ice genie heard and complied!! :)

Apocalypse4Real

For those interested in a global temperature forecast for July-Sept 2012, the IRI forecast is pretty grim globally and for the Arctic.

http://portal.iri.columbia.edu/portal/server.pt?open=512&objID=944&PageID=7868&mode=2

Peter Ellis

Barrow ice looks to be gone. MODIS shows a few scattered lumps (pressure ridges?) holding on, but the webcam is open ocean, and MODIS has nothing around Point Barrow itself. It's been pretty foggy up there, and the winds have blown the drifting pack ice near the shore, so it's hard to be sure when it actually broke up. The forecast page never came online this year, nor the mass balance buoy. Such a shame.

Reckon it's worth emailing them to ask what the actual breakup date was, and how it fits with previous years?

Espen Olsen

Peter,

But strangely those lakes or lagoons behind Barrow are still ice covered?

Neven

Peter, I had some contact with someone from the University of Alaska, Fairbanks, a couple of days ago and he told me that break-up occurred on June 29. This would have been the earliest since 2004, which was a year when the landfast ice was poorly grounded and broke-up earlier due to wind and ocean currents. They hope to have another break-up forecast next year.

Peter Ellis

Espen: Freshwater lake?

Apocalypse4Real

The CT NH SIA for day 184 just got posted on the graph - 6.21648 km2.

Rlkittiwake

"Ice genie heard and complied!! :) "

Thank you so much!

I was worried it was a slightly rude request, but it looks great! I'll accept it as a great birthday present!

Otto Lehikoinen

the floe obuoy#6 is on looks kind of blue: http://obuoy.datatransport.org/monitor#buoy6/webcam

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