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Glacierchange.wordpress.com

Been looking forward to this update, I knew it was going to be eye opener. Thanks this will take hours, fun ones at that, to digest.

idunno

Scorchio!

http://www.youtube.com/watch?v=MuSPdsPWit0

WhiteBeard

While the seasonal swing in arctic insolation is most defiantly into its most abundant phase, at the surface it is still relatively puny in absolute terms. Though the sun now is above the horizon continuously in all the areas (except quite a bit of Hudson Bay and a small per cent of Davis Strait) where sea ice is present, people should remember that it’s never very far from the horizon. For only a few noonish hours, at relatively lower polar latitudes, and during a month on either side of the solstice does a billed cap or wide brimmed hat provide relief from the sun-in-ones-eyes experience whenever gazing in its direction.

The affect of that horizon hugging is to greatly increase the surface area that a given amount of radiation is disturbed over when compared to a location on the surface that’s perpendicular to the sun. Further, the effective optical depth, the of number atmospheric molecules between the Sun’s surface and the Earth’s, also is much greater and increases scattering from the GH gas effect on longer wave incoming radiation. The yearly averaged kWh/m^2 a plate set at the latitudinally optimum angle in the lower arctic or sub-arctic receives is less than half that of one set in a mid-latitude desert, and roughly three-quarters the energy of more humid and cloudy mid-latitude areas. Even at the narrow duration peak, it's only about 70-80% of the latter.

It doesn’t get quite as torrid as some of the language being used to describe the Arctic’s irradiance at this time of year. Nevin, it really wasen't you I noticed being overly empurpled, though “there is a huge amount of insolation there, more than anywhere on the planet” is wrong. It was probably some English bred dogs who went mad and got carried away in the comments for the last post or two. ;)

Alberto Silva

WhiteBeard:

In summer insolation in the Poles is bigger than in the equator, according to this NASA article:

http://earthobservatory.nasa.gov/Features/EnergyBalance/page3.php

This is incredible, but true. What keeps the poles so cold even in summer is the high albedo of snow/ice. If they melt, then...

Al Rodger

Alberto Silva.
The "incredible but true" source you link to presents the graphic showing "The total energy received each day at the top of the atmosphere depends on latitude." The numbers off the graphic give Arctic values at the summer solstice of some 47 units & equatorial peak values of 37 units. (Units remain unspecified in the link.)
These measures take account of Arctic day length (which WhiteBeard appears not to in his comment above?) but evidently does not take account of the increased optical depth of the Arctic atmosphere resulting from the low inclination of its summer sunlight.
Even so, the level of surface insolation over the Arctic in mid-summer is impressive, as is its (more obvious) total lack of insolation over a full 6 months of the year.

Greg Wellman

Thanks for that link Alberto. I was initially mislead by the first graph until I carefully read the captions of the first and second graphs to see precisely what they were showing. One caveat though - the second graph takes length of day into account, but it says "top of atmosphere", so the optical depth of the atmosphere may matter as WhiteBeard said. OTOH, scattering mostly just spreads the energy out - only a small amount is entirely back-scattered.

Kris

Do have a look at today's Bremen UNI charts.

Look at the situation of the Northwest Passage .

It's really in an unprecedented state for Juin 15th!

Rob Dekker

Thanks Neven,
Indeed it's like a slaughterhouse out there in the Arctic. Still, a couple of notes are in place :
The low CAPIE index may be caused more by the anomalously high IJIS extent record, and the anomalously low CT area record.
If we look at Arctic Roos area and extent, then it looks like area is low, but not as record-setting as extent, thus suggesting that the Arctic ice pack currently is small and rather 'compact', thus leading to a larger CAPIE index :
http://arctic-roos.org/observations/satellite-data/sea-ice/ice-area-and-extent-in-arctic
That may mean that the melting ponds (which kind of disappear in the course Arctic Roos resolution) are indeed responsible for the drop in CT area, and that actual ice pack is pretty tight right now.

With that situation in mind, and the harsh winter in the West Arctic, I still think that if the Beaufort gyre stops spinning, we may see a significant stall in extent and area. Maybe a very significant stall...

Rob Dekker

With the notion that I have been wrong before with predictions, especially the ones about the future...

idunno

Hi all,

CT area fell by 145k yesterday, which meant that the fall over the preceding week was 1.25M, one of the biggest weekly falls of all time.

Not as much as today. After a fall of 206k, the weekly decline is 1.3M.

The negative anomaly of 1.811M is the largest ever during the vernal half of the solar year.

The earliest that I can find a negative anomaly so large is on day .6000 - which is sometime about July 25.

Scorchio!

Seke Rob

[ot]Saw that sketch... it's funny, but the 'ch' is phonetically not right... we pronounce the ch as a 'k', in Italy that is [which is why this letter has not found it's way into our 21 letter, of old, alphabet] ;>) [/ot]

Scary, the CTGB01 and CTGB02 charts show the globe going off it's rocker... this is the period where actuals for global drop... Arctic goes down more than Antarctic can offset.

Seke Rob

IJIS going in smaller steps now. Last 3 days of actual and prelim:

13th 10346094 10279531
14th 10225000 10116406
15th 10200000 10097031
16th ???????? 10047031

Predicting a final number for the 16th of an even 10150000 +/- 0 for some latitude. Means that the fastest < 11 to < 10 million is no longer possible [stands at 9 for extent], but what to expect if these steps move ever earlier into the year. [was there not a 25th June prediction to drop below 10M, then that I fear is not going to hold.. but it's mostly all current weather dictating]

Derek

Kris. Its interesting to compare the modis images of the NWP with the Bremen charts. Melt pond issues perhaps?

Jim_pettit

CT SIA fell another 205,000 km2 yesterday. That's the eighth century break in a row (of which three have been double century breaks). That's also an eight-day drop of 1.458 million km2--an area larger than Texas, California, and New Mexico combined--and the single biggest eight-day decrease on record*. Sea ice area is now just over 8.2 million km2, which is half a million square kilometers less than second place 2007 had on this date.

"Death spiral" graph here...

* - Over the past several days, we've seen the largest eight-day drop in the CT record; the 3rd and 9th largest seven-day drops; the 5th, 8th, and 9th largest six-day drops; the 9th and 10th biggest five-day drops; the 6th and 10th largest four-day drops; the 8th and 9th biggest three-day drops; and the 12th largest two-day drop.

Kris

Derek wrote:

compare the modis images of the NWP with the Bremen charts.

IMHO it would be more useful to compare Bremen charts with each other.

And the point is we're looking at something "normally" to be seen only from the 1st of July on...

Heraclitus

I've updated my 3D graph showing change in IJIS extent since 2002. This doesn't show as much information as SekeRob's compound bar charts, but I think the visual impact is quite striking. Using major units of 750 000km^2 rather than 1 million or 0.5 million seems to produce the best balance.

I tried playing around with the formatting to see if it looked any clearer: version 1; version 2 (black is obviously much cooler). Not sure they add much.

I also made a version showing the 1979 to 2012 area data.

Apocalypse4Real

Kris and all,

In regard to the NWP and pond melt vs actual ice melt and breakup, the surface temp forecasts for locations along the passage point to continued and likely accelerated melt. Here are some data points:

Pond Inlet Airport - above freezing since 1 June, and is forecase to be around to above freezing through 23 June. Beginning 24 June temps go above normal - forecasted highs of 9-10 C. http://weatherspark.com/#!dashboard;ws=28273

Resolute, CA, been above freezing sine 8 June, and is forecasted to be above freeing through 25 June, with highs reaching 9-10 C some days. See: http://weatherspark.com/#!dashboard;ws=28166

Steffanson Island, CA, temperatures have hovered at or above 0C since 9 June. However, the forecast is for higher temps through 25 June, hitting a high of 17C on the 24th. See: http://weatherspark.com/#!dashboard;ws=28170

Sachs Harbor, CA has been generally above 0C since 26 May, and in the next 10 days will experience increasing temps with a forecasted high of 19C on 25 June. See: http://weatherspark.com/#!dashboard;ws=28375

Farther north, Eurkea, CA has been above 0C since 1 June and is forecasted to remain above freezing through 25 June, with highs some days of 9-10C. See: http://weatherspark.com/#!dashboard;ws=27709

These past and forecasted conditions point to accelerated melt and breakup of NWP sea ice.


Apocalypse4Real

Another indicator of the NWP thaw is Rutgers' snow and ice anomaly chart for 15 June:

http://climate.rutgers.edu/snowcover/chart_daily.php?ui_year=2012&ui_day=167&ui_set=2

Seke Rob

The daily gate closer, MASIE, reported a 55.8K drop from the 14th to the 15th, but also lost 70K on 2011, to now be 108K behind same date, last year. Interesting is that the Greenland Sea rose by 33K, where the Arctic Basin as a feeder, did not move at all [Kara, Laptev, ES, Chukchi, Beaufort sum to slightly reduction as wind/gyre driven feeders to the basin]. [Think] We are looking in general at stretching of the available floating area... the more stretching, the more vulnerable [no revelation]... whilst CT comparison of June 12 is like a Donald Sutherland experience, looking back in Venice [hit by a Trombo last week, ripping off roofs of many a historic building].

Apocalypse4Real

Another view of the rapid sea ice melt - the NCOF imagery. Compare 11 June and 15 June. Very sobering!

http://behemoth.nerc-essc.ac.uk/ncWMS/godiva2.html#

Aaron Lewis

This year, the two big changes are 1) the ice is weak enough to be easily broken up by wind, and 2) there is more water vapor in the atmosphere.

NH circulation patterns have changed. Previously, water vapor from tropic and temperate zones mostly condensed out before the air mass arrived over the sea ice. Now, water vapor is flowing freely over the Arctic from temperate and tropical regions. Even with dense cloud cover, a warm, moist breeze off of the North Atlantic can melt ice faster than a still and sunny day -regardless of melt ponds reducing the albedo effect.

The number to watch is not the local temperature, but the local dew point. When the dew point is above 0C, the ice is melting very fast. If there is any breeze at all, the ice is melting wicked fast.

As I have posted here a couple times this spring, I expect all previous records of sea ice melt to be obliterated this year. The system is moving toward its next stable condition, which is seasonally ice free.

I consider the Arctic "ice free" when there is not enough ice for the seals to pup and the polar bears to hunt.

Artful Dodger

Aaron,

Seasonally sea ice-free is not a stable condition in a warming Arctic. The Arctic ocean will stabilize as either perennially sea ice covered or perennially sea ice-free, depending on forcings.

c.f. Eisenman & Wettlauferb (2008) Nonlinear threshold behavior during the loss of Arctic sea ice

Figure 3 (Bifurcation diagram for the full non-linear model) shows that it takes just an additional 3 W/m^2 to drive the Arctic from seasonally sea ice free to perennially sea ice free.

Seke Rob

"When Graphs Agree", surely someone tried this little ditty before (rough edged): MASIE versus JAXA . Suspect that. in amongst, the wider inclusions [Yellow Sea e.g.] makes for the bigger difference in winter.

Kris

Apocalypse wrote:

Another view of the rapid sea ice melt


And yet another oddity close to the absurd at Station Nord in Greenland:

Nord aws

Max temp the double as average. Minimum temp more as the quadruple as average!

Werther

Thanks Neven, great compilation.
I started CAD counting on r03c03, not very lucky with cloudcover day 160. While busy, I noticed definite change between days 162 and 167 over Nares Strait. Day 162 quite equal white ice, day 167 getting blueish, individual floes showing up . The warmth, measured in Eureka and Alert, is also slashing the Nares ice. There are colour bands in front of Peterman Glacier, one of them white, looks like a band of debris, fed from the glaciers on the fjord bank. Melt ponds are showing up on the Peterman. Day 168 indeed marked 8 dC on Jokelbugt (Station N) and Cape Morris Jessup. The snowline has gone up considerably on the corresponding icesheet. Snow cover on the icefree parts is vanishing.
Buoy 4 is now right in my count area. At 125 km NE of Cape Morris Jessup it shows a respectable pressure ridge and the suggestion of a big lead. Ice went south 60 km in the last week.

Neven

Thanks for the info, Werther. Coincidentally I was thinking about your CAD comparisons. Keep us up-to-date.

It doesn’t get quite as torrid as some of the language being used to describe the Arctic’s irradiance at this time of year. Nevin, it really wasen't you I noticed being overly empurpled, though “there is a huge amount of insolation there, more than anywhere on the planet” is wrong.

Thanks, Whitebeard! So open water in the Arctic is receiving less solar energy in 24 hours than say the equator (not at the top of the atmosphere, but at the surface)? If you or someone else can confirm this, I will tone down my language. :-)

Rlkittiwake

By what mechanism would the Arctic Ocean remain ice-free even in the winter?

Areas such as the Okhotsk Sea have ice on a strictly seasonal basis, and that is normal for them.

Has anyone taken the derivative of a curve such as the CT SIA?

D

The Arctic Sea Ice melting...

It's daily record lows for volume, area, and extent...like 5 or so days in a row now.

15%, 30%, Area, Volume...

incredible.

Steve Bloom

FWIW, just now max insolation at low lats would be approaching the Tropic of Cancer, significantly north of the equator.

Rlk, I'm not well-informed about the details, but I think the idea is that when the Arctic inverted thermocline (with the lens of colder, fresher water at the surface and the warmer, saltier water below kept away from the atmosphere), things will warm up a bunch, even in the winter. Bear in mind the vastly greater thermal capacity of the AO vs. the overlying atmosphere. Even then, though, I would expect relatively shallow, isolated bodies of water, perhaps including the SofO, to freeze over somewhat, as it will take quite a bit more warming before winter is abolished.

Steve Bloom

I see that WTF has weighed in with the predictable Gish Gallop, pretty much just phoning it in.

Steve Bloom

when the thermocline *destabilizes*

Ghoti Of Lod

According to this Natural Resources Canada map ( http://goo.gl/qXso9 ) the Mean daily global insolation for the northern arctic islands is in the range of 6.7 - 8.5 kWh/m2 in June.

Brazil seems to average around 6 kWh/m2 so I'd not discount the power of the sun when looking at ice melt in June.

Kris

Rikittiwake asked:

By what mechanism would the Arctic Ocean remain ice-free even in the winter?
.

By the influence of the Gulf Stream of course.

Remember, the Okhotsk Sea is situated at the Eastern, thus cold side of the Euro-Asian continent. No warm drifts present and always cooled down by the influence of cold streams coming from the Nord, even in summer.

Remember and compare too, the Okhotsk Sea is situated at exactly the same lattitude of the North Sea, which gets never covered with ice in winter. Never.

Albeit sinds the end of the last ice age.

Rlkittiwake

While I appreciate the explanations, I'm still not sold, in part because of the massive distances that these currents are travelling.

By my eyeball of a world map, the difference in latitude between the North Sea and Svalbard is about 25 degrees, which is close to the difference between Anchorage and Tokyo or Anchorage and Los Angeles. (I know this isn't the best comparison, but go with me for a moment here.)

In the northern summer, 27/80 degree water from Japan goes up to the Gulf of Alaska where it cools, and by the time the water gets to LA it's about 17/60 degrees. (People who come to California are often very surprised at how cold the water is here.)

While the Gulf Stream certainly influences the climate in both the North Sea and Svalbard, conditions in Svalbard are very different than those in the North Sea.

Even though the water starts out downright hot in the Caribbean, it's still relatively warm by the time it gets to the North Sea, and it's often warm enough to keep the waters around Svalbard ice-free in the winter, once it gets up that far it cools off quickly, especially in the winter when it's totally dark and the ocean is surrounded by all that frozen land.

Bob Wallace

" once it gets up that far it cools off quickly, especially in the winter when it's totally dark and the ocean is surrounded by all that frozen land"

That warm water is also encountering a lot of ice left over at the end of the melt season right now.

Once "all" of the ice is gone at the end of the summer warm currents will enter much warmer conditions of no ice and higher water temperature as more of the summer heat will have gone to heating water than in the past.

Additionally one shouldn't expect the land masses to be as frozen as they were. Overall there will be less stored "cold" to counteract the incoming warmth. Each year we pull down the reservoir of stored cold.

Aaron Lewis

Artful,

Today the AO exchanges heat with other regions in ways that are not captured in that model. Water vapor from the south now heats the Arctic in the spring, and in the fall, the cooling land masses act as heat sinks.

adelady

H3ll's teeth!

Just did the usual CT comparisons. 14th June, 2010,11,12.
http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=06&fd=14&fy=2010&sm=06&sd=14&sy=2012

and http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=06&fd=14&fy=2011&sm=06&sd=14&sy=2012

Does anyone have the numbers readily available for <60% concentration daily?

This really looks like someone used _real_ butter icing on a cake under the studio lights. It's just thinning, slipping and sliding away.

Artful Dodger

Yes, Aaron. Which is part of the reason crocodile fossils can be found on Ellesmere Island. Paleoclimate data shows a perennially sea ice-free arctic, with a climate stable enough for cold blooded reptiles to expand their range that far North.

Steve Bloom

Rlk, ocean currents are much more than just on or near the surface. E.g., much of the heat currently eating away the ice pack at the Atlantic margin comes from the tropical Indian Ocean via the Agulhas current. That heat is largely retained during its long trip north since it's carried at medium depth. You may have good intuition, but try collecting all the facts before drawing a conclusion.

Account Deleted

Kris,

RE: Bremen UNI charts for the Northwest Passage.

I suspect it is a problem with the sensor and melt ponds rather than an unprecedented state. Look at yesterdays modis image for that area

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r04c02.2012168.terra.500m

Lots of Blue ice, but not much open water - I think this may also be the reason for the rapid decline in SIA for the CA shown by CT

Rlkittiwake

Hi Steve Bloom,

Where have any of us pretended to have any answers? Even the more "expert" people here are generally very cautious when making future predictions.

I certainly don't pass myself off as an expert, just an interested lay person who has watched the ice melt every year since 2007. All of my knowledge of albedo, heat transport, and ocean currents comes from a climatology class I took 10 years ago as part of a degree in watershed management.

If and when I comment on here, it's because I am interested in the discussion, not because I have drawn any particular conclusion.

The only prediction I am willing to bank on?

Scorchio!

Account Deleted

The blue ice problem is also causing issue for Uni Bremen readings for the Kane Basin/Nares Strait

Werther

Day 168 fast ice began breaking up in the Laptev and East Sib Seas. It's strong, watch day 169 near the Lena and Kolyma delta's.

Werther

I don't have any numbers comparable to last year yet. But from what I've been doing in CAD I'd say the ice in the 90K area north of Greenland has continued to be shredded. I have roughly inserted Obuoy4's coordinates. Think it is likely on a 90km2 floe on the south side of the study area. Looks really particled around there, on it's way to Fram. Whether that buoy will float soon, can't tell. But today's image shows the beginning of melt ponding and the open lead in the back right side widening.

Espen Olsen

Colin: The blue ice problem, is similar to what you see Kimmirut, where the ice is covered with melt water.
http://www.kimmirutweather.com/

Espen Olsen

Polarstern left Bremen on June 13 and is cruising along the Norwegian coast towards the Pole, what USCGC HEALY is up to, remains to be seen.

Eli Rabett

Eli may have missed when someone wrote it above, but FWIW a major reducer of energy absorbed at high latitudes is the angle of incidence. At glancing angles the amount of reflection from surfaces goes to 100% (this makes it possible to reflect x-Rays)

Peter Ellis

That's not as relevant as you'd think, given that the sea surface isn't actually flat, and is constantly in motion.

http://snowdog.larc.nasa.gov/jin/Papers/jingrl04.pdf

That's actual measurement of albedo. Look at figure 1 - broadband albedo peaks at between 0.2 and 0.3 (i.e. 20-30% of energy reflected) when cos (solar zenith angle) ~= 0.1, i.e. an angle of 5 degrees above the horizon.

At the moment, the Sun is ~23 degrees above the horizon, and the albedo across the Arctic ocean will be around 0.1 going by that figure. Not hugely significant.

idunno

Hi all,

CT reporting 8.02M, a fall of 174k.

Anomaly now 1.89M.

Tor Bejnar

A big chunk of the ice bridge/arch at Kane Basin disappeared (toward the Canadian side) under the clouds these last couple of days. I wonder if the clouds brought rain. Collapse of this ice bridge seems imminent to me (within a week?).

Neven

CT now 9 century break days in a row. One more and we have a record series? Yes, I'm looking at you, Jim Pettit.

I'm probably being dim here, but can anyone tell me whether open water in the Arctic is currently receiving less solar energy in 24 hours than say the equator (not at the top of the atmosphere, but at the surface)?

Rlkittiwake

I found this insolation graph on the internet:

http://www.physicalgeography.net/fundamentals/images/insolation_latitude.gif

Aaron Lewis

Artful,

I fully agree that the Arctic Ocean will go to a year round, ice free state. A 3 watt/m^2 difference suggests the AO could go from seasonal ice free to year round ice free, without pause. I suggest that it will take at least ten years.

Artful Dodger

Hi Aaron,

The trend given by PIOMAS exponential curve fits also suggests about 10 years to transition from seasonally sea ice-free to perennially sea ice free in the Arctic Basin.

https://sites.google.com/site/arctischepinguin/_/rsrc/1338919799127/home/piomas/piomas-trnd2.png

Wipneus, may I suggest you add one additional graph to your fine arctischepinguin page?

"PIOMAS Yearly Maximum Arctic Ice Volume"

Taak, my friend!

Artful Dodger

Hi folks,

The time series of scientific measurements of solar insolation is well established, as pointed out by our friend Rob Dekker here at the ASI blog on May 24, 2011 at 02:43

Pt Barrow, Alaska has been home to the Naval Arctic Research Laboratory since August 1946. The NARL chart below shows daily measured insolation at the surface at 71.3 N latitude, from 2010. The maximum measured insolation was over 370 watts (remember these are measurements take at the surface by actual scientists ;^)

This time of year, daily total insolation values only increase as you go North. Note that the distance from Pt Barrow to the North Pole is 1,122 nm (2,278 km). At the Pole itself on Wednesday June 20, the Sun will not dip toward the horizon at all. Instead it will do one complete revolution of the horizon while staying at 23° 26′ 16″ altitude the whole day (cool, watt ;^)

Kevin McKinney

"So open water in the Arctic is receiving less solar energy in 24 hours than say the equator (not at the top of the atmosphere, but at the surface)?"

Not true, according to Rikkitiwake's link, above--but in explaining this fact, don't forget that 90 gets 24/7 insolation at this time of year, while the equator is limited to a boring old 12/7, pretty much. So the high Arctic starts with a 2:1 advantage (if you want to call it that) *before* accounting for angle of incidence--which doesn't operate linearly, BTW:

http://en.wikipedia.org/wiki/Albedo#Water

Kevin McKinney

BTW, just saw this comment of Lodger's on the "Fringe" thread, and thought I'd quote it here, as it seems to frame the "perenially ice-free Arctic Ocean" in an understandable way:

The Arctic will be a new lobe of the Atlantic, and will no more freeze in Winter than the North Atlantic does now.

I'd only add that by contrast, you get seasonal ice on *sheltered waters* much, much farther south than anything we normally talk about here--so that the size and insularity (or otherwise) of a body of water also seem to be significant variables to consider in connection with potential freeze-up.

Bob Wallace

The ice is disappearing on sheltered waters as well.

"Ice cover on North America’s Great Lakes–Superior, Michigan, Huron, Ontario, and Erie–has declined 71% since 1973, says a new study published in the Journal of Climate by researchers at NOAA’s Great Lakes Environmental Research Laboratory.

The biggest loser of ice during the 1973 – 2010 time period was Lake Ontario, which saw an 88% decline in ice cover. During the same time period, Superior lost 79% of its ice, Michigan lost 77%, Huron lost 62%, and Erie lost 50%. The loss of ice is due to warming of the lake waters."

http://thinkprogress.org/climate/2012/03/31/455612/great-lakes-ice-cover-down-71-since-1973/

Doug Bostrom

That death spiral graph by Jim Pettit is a very useful visualization, solves some problems with other perspectives.

It's also a nice pun.

Artful Dodger

Agreed, Doug. Very nice job, Jim!

Any chance you could create a version of the chart with time on the Z-axis?

Then the "Death Spiral" will truly pop out!

Cheers,
Lodger?

DrTskoul

Nares ice bridge seems to be receding. Just compared days 165 and 168. Edge of bridge receding (too lazy to compute velocity), but a floe from last year, glued by first year ice, seems ready to go.

Day 165 - 168 comparison

Seke Rob

Noticed on the SST temp chart posted earlier today that the regular featuring Polynya may have shown it's face again in the Fram Strait. Any MODIS or other imagery displaying this?

DrTskoul

Just by eyeballing (..I know what can go wrong with that technique...), it seems that the weakest points of the Nares ice bridge are retreating by about 10 - 30 meters/hr or 8 mm/sec.

DrTskoul

(..I know what can go wrong with that technique...)

Meant to sound sarcastic i.e.

...I know...what can go wrong with that technique???

DrTskoul

(..I know what can go wrong with that technique...)

Meant to sound sarcastic i.e.

...I know...what can go wrong with that technique???

DrTskoul

I maybe completely off...(newbie in Arctic geography)..but MODIS shows and area of open water at the beginning of the farm strait

Farm Strait Polynya???

DrTskoul

And the last graph, the regional decline of MASIE extent from day 82:

MASIE Regional Extent Update for Day 168

DrTskoul

Can somebody notice what is wrong with this picture?

Canadian Archipelago Ice Area from CT

Neven

So SIE is already showing signs of slowing down. When will SIA follow? Or will that big low over Beaufort/Chukchi and those highs over the Siberian coast keep things on the move?

Somehow I don't think that low is going to stay for long. Maybe 4-5 days. The weather forecasts are changing a lot from day to day, so it can go either way.

Wayne Kernochan

@Neven - congratulations on a superb ClimateProgress post.

Can I suggest one naive way of assessing melt ponds? I look at the sea ice concentration map, and then the ARC sea ice thickness map. I take the concentration map light blue colors to be where there may be melt ponds, and the thickness map to indicate how likely they are to be real open water -- and whether they will or will not be real open water at minimum (area).

This would suggest that:

(a) if the Hudson's Bay/Greenland ice is melt ponds now, it's going to be open water at minimum.
(b) based on past history, it's not clear that all of the above-Alaska "open water" will turn out to be real.
(c) the area that seems significantly different from the last few years is above eastern Siberia. There, the melting plus the fact that there appears to be less than 2 meters this early almost all the way to the Pole suggests that while this was not open water at minimum in previous years, it may well be this year.
(d) and we haven't touched the western Russia portion, which is not showing up as melt ponds but which also may melt almost all the way to the Pole.

Summary: I would guess, based on that, that we should keep our eyes mostly on the ice between Russia and the Pole in the next two months, with some attention to the ice above the Bering Sea. The more that shows completely open water near the Pole, the more likely we are to see a major dip in area at minimum.

What did I miss? - w

AmbiValent

I assume with "Greenland ice" in (a) you mean Baffin Bay, not Fram Strait. I'm mostly with you here, as it seems that ice no longer "orbits" the North Pole, but is carried towards the main ice mass at the Canadian Archipelago, and towards Fram Strait from there.

As icebreakers found out last year, the ice around the North Pole was so rotten they could go through at maximum speed, so there's a lot of room for compactification if ice from Siberia is carried towards the Archipelago. Which I guess means the Eastern Hemisphere will see a record melt this year even if the Western one won't.

Kevin McKinney

Bob Wallace, you are quite correct--and actually, I believe I've cited that very paper here in the past!

But even well to the south of the Great Lakes, you get some seasonal freezing, which just reinforces the point I made--the bigger and more open the water, the greater its ability to resist freezing, since the potential for heat to advect in and/or 'mix up' during the winter is greater. That's independent of the fact that ice loss proceeds in all of these cases--which it certainly does, as you point out for the GL case.

BTW, if I'm correct with this idea, one consequence would be that Hudson Bay might possibly be expected to form seasonal ice for a time even after the central Arctic Basin largely ceases to do so.

Account Deleted

DrTskoul
The Modis image doesn't support this rapid decline in SIA in the CA. It appears to be that CT/Uni Bremen and others are confusing melt ponds with open water. So we need to add a couple of hundred thousand Km^2 to the SIA figure.

michael sweet

Doug Bostrom linked this interesting graph from Jim Petit.

http://iwantsomeproof.com/extimg/sia_2.png

Perhaps it could be added to the long term graph page?

Steve Bloom

Hmm, yeah, kind of a ... death spiral.

Chris Biscan

Both the Euro and GFS now go to a Dipole Anomaly again with a backdoor HP torching the Kara and Laptev before the SLP moves from the Canadian Basin back to the Kara as a HP breaks out on the Canadian side.

The result is 20C 850s hitting the Southern Beaufort.

Some of the projected anomalies are 15C+ 850mb that is a torch all the time somewhere up there.


This keeps a general flow towards the Fram. So the ice will compact and melt and melt and melt.

The Beaufort may end up empty like 2007 and 2011 by late July.

We could be seeing a new record in the 3.5-3.8 mil km2 range extent.

If we get a dipole most of the summer, we will see a huge area of arctic ocean open. Which will also be a huge heat release.

Already major heat is in the water up there.


crazy time indeed

Tzupancic1

Chris,

Looking at Euro I see a prominent low pressure system north of Alaska. http://www.wetterzentrale.de/topkarten/fsecmeur.html I don't see an arctic dipole anamoly at all from the Euro forecast. Instead, it looks like the next weather period will be quite distinct from the dipole anamoly just experienced.

Neven

Tzupancic, the 216hr and 240hr forecasts show a renewed dipole, but this is so far out that a lot can change in the meantime.

For the first time since a while I'm not seeing any big day-to-day changes on the UB SIC maps.

Oh, and BTW, that big drop in SIA for the Canadian Archipelago is probably an artifact. It wasn't nearly as low the day before yesterday.

Werther

Hi Neven,
Looks like WindSat and other equipment is fooled by melt ponds and extended meltwater layers everywhere. Not that it matters much; all of these areas are rapidly melting. In the CAA McClure Strait, Prince of Wales Strait, Amundsen Gulf all show first signs of breaking up/melting out.It's just a matter of time. Volume is dwindling...

Tzupancic1

Neven,

Well said. Fact is key Arctic Sea Ice events the next few weeks are very interesting, but not clear, especially given the current change in the weather.

Tzupancic1

Looking at the Arctic Sea Ice melt,heat must be entering this system. The most likely source would be adjacent oceans.

Werther

Look what's going on around the core of the low between Chukchi Sea and Basin:
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r04c04.2012170.terra.250m

My take is that the usual stall in periods of big lows/negative AO during summer doesn't work anymore. The pack is too thin and mobile and warmer waters are easily stirred up.

Seke Rob

Thanks to the various pointing me in the direction to rediscover the MODIS Mosaic http://lance-modis.eosdis.nasa.gov/imagery/subsets/?mosaic=Arctic.2012169.terra.4km . Change the link to the day number [which is how I do this] and drill in... my Fram polynya, the Kane bridge, the Beaufort black hole. Who knows this summer some [more] commercial ship plumes on highest resolution imagery. :(

Parked the link in a very long running denialista thread [of the usual suspects], so the random visitors can home in for themselves and wonder about 'recovery' and 'hidden' decline.

Werther

I've got a serious problem with opposites. I meant big low/positive AO

Chris Biscan

Tzupancic,

No, most of it is coming from ridging creating large HP's and sunny conditions which have caused the main areas of water to open up.


The Beaufort has 5-6C water temps, that is crazy really. That came from the Sun.

Steven Newbury

I'm not convinced the MODIS imagery of the Canadian Archipelago can really discount the accuracy of the drop in concentration. As far as I can see the Alaskan side is showing quite a lot of deterioration. As to the rest, even if there is a large amount of melt-ponding, the ice is now very thin and will likely be breaking up in the next few days.

Account Deleted

The problem is Uni Bremen and others are showing that the CA should be a mixture of open water and ice, but Modis shows that most of the ice is still relatively intact. From Modis it is hard to argue that 1/3 of the CA ice has disappeared - which is what CT is suggesting. I won't be suprised if denialists started to pick up on this apparent discrepency and start making noise. A good case for ground-truthing your remote sensing data.

Seke Rob

Let's see: IJIS/JAXA makes adjustment for melt-ponding and factors this in from early June... would others be daft to not do that? Let's get the facts before more of these 'alarm-ing' ;>) doubt curves throwing. All use multi day averages at that, some up to 5 days. Artifacts are always possible, so I'm looking at series, not individual / isolated outliers [the ol "one is wrong, so everything must be wrong too" knee-jerk lurkers can stick it]. As noted, if Nansen-ARCTIC ROOS is breaking records, some hearts are getting seriously broken too in the not-true camp.

michael sweet

The satellites also have edge effects that affect the ice area. CAA is mostly edge so that might be affecting the result there.

Seke Rob

That's exactly what I was thinking while having my daily power-walk down the hill and up [with 7Kg more in the backpack, in 33C, 49% humidity and forecast of steel blue skies through the next weekend, at least].

DrTskoul

CT area below 8 (7.947) sq.km. Anomaly almost -2 million and we are not at the end of summer yet.

Seke Rob

Whilst, Arctic CT anomaly went to -1.91M with lowest 6 for days 166+167 in 34 years:

Date--------- Day -Anomaly- -Actual.km2- Avrg79-08
15-Jun-2007 166 2007,4548 -1,3104861 8,6103086 9,9207945
16-Jun-2007 167 2007,4575 -1,3185904 8,5394611 9,8580513
16-Jun-2010 167 2010,4575 -1,4253552 8,4326963 9,8580513
16-Jun-2011 167 2011,4575 -1,4118645 8,4461870 9,8580513
14-Jun-2012 166 2012,4548 -1,8908894 8,0299053 9,9207945
15-Jun-2012 167 2012,4575 -1,9107149 7,9473367 9,8580513

Below 8 million actual now (autocue for Jim Pettit ;>)

And the global number went to -1.546M (a record for days 166/167 of the year since 1979). The top (or bottom 5) for these dates in past 34 years:

Date--------- Day -Anomaly- -Actual.km2- Avrg79-08
16-Jun-1995 167 -1,0313485 19,3616447 20,3929939 0,4516912
15-Jun-2007 166 -1,3932407 18,9782925 20,3715324 -0,8887545
16-Jun-2007 167 -1,2948525 19,0981407 20,3929939 -0,8896231
16-Jun-2011 167 -1,1057770 19,2872162 20,3929939 -1,0376556
14-Jun-2012 166 -1,5467937 18,8247395 20,3715324 -0,9360047

Jim_pettit
autocue for Jim Pettit ;>

Cue received. ;-)

As DrTskoul and Seke Rob both noted, with yesterday's drop of "just" 82k km2, CT SIA has fallen to 7.94 million km2. That's the earliest area has fallen below 8 million, and in fact the first time it's ever done so before day 170; the long-term average has been day 186.

The 79 days it's taken area to drop from its maximum to below 8 million this year is by a huge margin the fastest that's ever happened. In fact, it's never before taken fewer than 100 days (1999 and 2003), and has taken as many as 144 days (1992). The 1979-2011 average is 118 days.

Okay, now for the really obscure stats. ;-) Over the past ten days, we've seen the following decreases:

-Ten-day drops: the 2nd & 3rd largest on record
-Nine-day: 1st, 3rd, & 5th
-Eight-day: 1st, 2nd, & 4th
-Seven-day: 3rd, 4th, & 10th
-Six-day: 5th, 8th, & 9th
-Five-day: 9th & 10th
-Four-day: 6th & 10th
-Three-day: 8th & 9th
-Two-day: 12th

The CT SIA record spans 12,221 days.

Kevin McKinney

A wild ride this last fortnight, for sure. And to think that a number of us here were looking for a slowish season just a month or so back! But as we all know, the system appears to just love making ice prophets look foolish--in the short term, that is.

So how will it do that as this season plays out? I'm thinking that the tide is apt to run towards greater rather than lesser losses as we get into August, but that's little more than guesswork and a gut feeling about the general low trop temp trend.

Yet another deeply-felt hat tip to all the folks who take the time and trouble to peer more deeply into the data than I can or will!

Shortfatape

We seem to be getting into a lot of discussion about how the methodologies for CT area (and others) may not accurately reflect reality, actual conditions, ground truth, et al. With remote sensing, that is always a discussion, whether things are looking crazy (like now) or stable.

The real question is whether or not the methodology has changed. If it hasn't, then the current high rate of change is the real discussion, not whether or not the actual numbers are 1% or 5% too high or too low. We presumably always see melt ponds at this time of year, right? The sensors presumably saw them (or didn't see them) as open ocean in past years, right?

...So, can we confirm that CT's methodology is the same? (We know to use a little caution with IJIS because of their sensor switch.)

Aaron Lewis

Artful,
Better to look at the Navy model that includes more latent heat transfers. See http://www.oc.nps.edu/~pips3/spinup_output.html

Dave Leaton

I'd add to Jim's posts that the ten day period ending yesterday was just 4015 sq km short of the 1999 10-day record drop. The 1999 run that holds the record was almost the first 10-day century run on record. The recent run is the third on record (1995, 2010). Drop runs are far shorter than gain runs. The 17-day century gain in 1995 holds that record.

Dave Leaton

amendation: "The recent run" > "The recent nine-day run"

Twemoran

Big Bite out of Nares today.

Terry

Seke Rob

How deceptive light and veiling clouds and shadows can be. Compare 16th with 17th for that cadre, and my untrained eye taking it as if ice was put back [that center big wedge:

http://ocean.dmi.dk/arctic/images/MODIS/Kane/20120616TERR.jpg

http://ocean.dmi.dk/arctic/images/MODIS/Kane/20120617TERR.jpg

[fixed the second link, N.]

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