Home brew AMSR2 extent & area calculation

[Hyperion]

Better clarity on todays Worldview :
https://worldview.earthdata.nasa.gov/?p=arctic&l=MODIS_Terra_CorrectedReflectance_TrueColor(hidden),VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines&t=2017-07-16&z=3&v=-2830402.4283675756,-712743.4806649983,1363901.5716324244,1413080.5193350017&ab=off&as=2017-04-15&ae=2017-04-22&av=4&al=true

"Melting in Situ" sure looks correct. And it looks like ramping up in the next few days with the heat and rain coming in. Not just there but all fronts.

[Wipneus]

Moderate declines but extent closes the distance with 2012 and 2016.

Update 20170716.

Extent: -74.6 (+55k vs 2016, -486k vs 2015, -262k vs 2014, -147k vs 2013, +84k vs 2012)
Area: -57.0 (+242k vs 2016, -227k vs 2015, -401k vs 2014, -235k vs 2013, +91k vs 2012)

The details (in 1000 km²):


Extent:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                  -12.5                    -2.4                    -4.9
               Kara Sea             Barents Sea           Greenland Sea
                  -22.1                     3.9                    -2.9
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                  -19.3                     0.0                    -7.1
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                   -9.5                     3.3                    -0.7
             Bering Sea          Sea of Okhotsk            Total Extent
                    0.2                    -0.6                   -74.6

Area:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                  -49.4                    29.2                     6.7
               Kara Sea             Barents Sea           Greenland Sea
                  -21.4                     8.7                    -3.5
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                  -20.7                     0.0                     0.2
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                  -34.5                    13.2                    14.4
             Bering Sea          Sea of Okhotsk              Total Area
                    0.3                    -0.3                   -57.0


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

[Wipneus]

No Fram export to speak of. Some of the fast ice has chipped off.

[Wipneus]

Extent drop same as yesterday (~75k), area just a small 15k.

Update 20170717.

Extent: -74.4 (-20k vs 2016, -415k vs 2015, -287k vs 2014, -113k vs 2013, +105k vs 2012)
Area: -15.7 (+268k vs 2016, -120k vs 2015, -393k vs 2014, -184k vs 2013, +207k vs 2012)
 
The details (in 1000 km²):


Extent:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                   -2.8                   -16.0                    -7.1
               Kara Sea             Barents Sea           Greenland Sea
                  -11.9                     2.4                   -13.3
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                    3.5                     0.1                    -0.1
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                   -7.6                    -5.0                   -16.1
             Bering Sea          Sea of Okhotsk            Total Extent
                   -0.2                    -0.3                   -74.4

Area:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                   12.7                   -10.8                    -4.2
               Kara Sea             Barents Sea           Greenland Sea
                   -4.5                     1.3                   -14.3
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                   -4.0                     0.1                     8.5
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                   -9.1                     6.0                     3.0
             Bering Sea          Sea of Okhotsk              Total Area
                   -0.2                    -0.2                   -15.7


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

The detail is the "Barents Bite". Good eyes may spot that some polynya are getting resolved (by the excellent UH sea ice concentration product) for the first time. Single (red) pixels for now, nothing like 2013 yest.

[Wipneus]

Continuing declines, typical for the time of year. Sea ice concentration drops in Laptev, ESS and Chukchi.

Update 20170718.

Extent: -85.3 (-54k vs 2016, -367k vs 2015, -314k vs 2014, -101k vs 2013, +108k vs 2012)
Area: -101.2 (+266k vs 2016, -94k vs 2015, -378k vs 2014, -175k vs 2013, +109k vs 2012)
 
The details (in 1000 km²):


Extent:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                   -7.8                    -1.8                    -2.9
               Kara Sea             Barents Sea           Greenland Sea
                   -5.2                    -6.4                    -2.5
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                   -9.0                     0.0                   -15.9
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                   -9.3                   -13.8                   -11.2
             Bering Sea          Sea of Okhotsk            Total Extent
                   -0.3                     0.6                   -85.3

Area:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                   12.0                   -30.6                   -19.3
               Kara Sea             Barents Sea           Greenland Sea
                   -6.1                    -5.0                    -6.8
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                   20.8                     0.0                   -24.7
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                  -13.6                    -6.8                   -21.4
             Bering Sea          Sea of Okhotsk              Total Area
                   -0.1                     0.5                  -101.2


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

[Wipneus]

Ice in about all possible NW passages turns mobile.

[greatdying2]

Ice in about all possible NW passages turns mobile.

All at once? That doesn't seem normal...?

[JayW]

Looks about the same as last year.

http://forum.arctic-sea-ice.net/index.php/topic,382.msg83770.html#msg83770

[Tigertown]

Ice in about all possible NW passages turns mobile.

That's what I have been saying. Normally the ice in the CAA would have been a backstop for compaction, now it becomes simply another escape route.

 JayW,

Looks about the same as last year.

Except this year, we can't afford it. The shape the ice is in, the whole Arctic will probably flush out like a giant toilet full of crushed ice.

[JayW]

That's what I have been saying. Normally the ice in the CAA would have been a backstop for compaction, now it becomes simply another escape route.

  The shape the ice is in, the whole Arctic will probably flush out like a giant toilet full of crushed ice.

Some toilets are quite powerful too.   

[jdallen]

Ice in about all possible NW passages turns mobile.

I also note Beaufort ice being driven south back across astonishingly warm water.  That won't be good for it.

[seaicesailor]

Ice in about all possible NW passages turns mobile.

I also note Beaufort ice being driven south back across astonishingly warm water.  That won't be good for it.

Exactly, compared to other years where some storms scattered the ice, this year the pack at Beaufort is staying so neatly compacted (yes, it can be fragmented and compacted simultaneously), any dispersion now won't do any good there

[epiphyte]

Ice in about all possible NW passages turns mobile.

I also note Beaufort ice being driven south back across astonishingly warm water.  That won't be good for it.

Exactly, compared to other years where some storms scattered the ice, this year the pack at Beaufort is staying so neatly compacted (yes, it can be fragmented and compacted simultaneously), any dispersion now won't do any good there

...The Beaufort ice has recently been fraying rapidly at the edges - especially toward the CAA. It just doesn't appear that way, unless one looks carefully, because of the combination of rapid clockwise gyration, deceptively high albedo, intermittent cloud cover and continuous southern-ward diffusion, all of which help obfuscate the disintegration of individual floes.

[Wipneus]

Drops in extent and area are big enough to stay close with 2012 and 2016. The ice in the Greenland Sea is dropping because the lack of Fram transport.

Update 20170719.

Extent: -89.3 (-40k vs 2016, -314k vs 2015, -381k vs 2014, -163k vs 2013, +38k vs 2012)
Area: -95.1 (+347k vs 2016, -102k vs 2015, -416k vs 2014, -195k vs 2013, -46k vs 2012)
 
The details (in 1000 km²):


Extent:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                   -2.0                    -6.5                   -14.5
               Kara Sea             Barents Sea           Greenland Sea
                  -12.9                    -5.5                   -23.1
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                   -7.3                     0.0                    -0.5
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                   -9.0                    -7.4                    -0.6
             Bering Sea          Sea of Okhotsk            Total Extent
                    0.1                    -0.1                   -89.3

Area:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                   29.9                   -17.7                   -13.8
               Kara Sea             Barents Sea           Greenland Sea
                  -22.6                     0.6                   -27.9
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                  -27.8                     0.0                    -2.1
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                   -2.0                     0.0                   -11.8
             Bering Sea          Sea of Okhotsk              Total Area
                   -0.1                     0.0                   -95.1



Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

[Wipneus]

Animation of Beaufort ice concentration, compared with 2016. This was the time when "Big Block" broke last year. No need for that now, the blocks are much smaller.

The animation will not start unless you click.

[Shared Humanity]

Given the fragmented nature of the ice and the SST anomalies, I am amazed by the compactness and resilience of the Beaufort as compared to last year.

I have to believe that this compactness serves to protect the ice.

[Andreas T]

Ice in about all possible NW passages turns mobile.

I also note Beaufort ice being driven south back across astonishingly warm water.  That won't be good for it.

the attached image https://go.nasa.gov/2vns6Kn
shows band31 IR overlaid over visible. The purple swirls of colder meltwater coming from the area of ice nearer the coast (ignore the cloud bands even nearer the coast) shows what happens to the ice , on the advancing ice edge of the beaufort gyre no such meltwater plumes show, presumably moving under the ice? This seems to me confirms what JD says, little protection from the sun warmed water for the ice moving south.
I compare consecutive days to help me distinguish slowly moving water plumes from fast moving atmospheric effects.

[seaicesailor]

Given the fragmented nature of the ice and the SST anomalies, I am amazed by the compactness and resilience of the Beaufort as compared to last year.

I have to believe that this compactness serves to protect the ice.

Watchig the weather forecast, there may be a couple of small storms passing just over the Beaufort, if it happens as 2015 and '16, they can be pretty disruptive. Still 60-90 days of bottom melt ahead in the Beaufort sea.

[slow wing]

Thanks again Wipneus for your amazingly informative plots - most recently the comparison between last year and this year of melting until the currrent date in the Beaufort Sea.

I agree, Shared Humanity, the large amount of dispersion last year in the Beaufort Sea was fatal for its sea ice. Indeed, it essentially melted out by the end of July! As far as I know this was earlier than any other year in the satellite record: see year comparison maps for Arctic sea ice at 1 August.

That won't happen this year but, as seaicesailor points out, there will still be a further month-and-a-half for the Beaufort ice to melt out and I expect that to happen.

[Thawing Thunder]

Put ice in a mixer: After the first second or so you'll have big chunks, a real broken up mess. Like 2016. Start the mixer again, and after a while you'll get something smooth an seemingly much more coherent. Like 2017. That's where you make Daiquiri from. But the ice is not really in better shape than the chunky pieces, though it certainly has a higher compactness and a better look. I think we are in Daiquiri times and there's still a lot to happen this season.

[liefde]

Put ice in a mixer: After the first second or so you'll have big chunks, a real broken up mess. Like 2016. Start the mixer again, and after a while you'll get something smooth an seemingly much more coherent. Like 2017. That's where you make Daiquiri from. But the ice is not really in better shape than the chunky pieces, though it certainly has a higher compactness and a better look. I think we are in Daiquiri times and there's still a lot to happen this season.

Exactly. And some seem to be forgetting the fact that the earth has been heating at a rate of 250 trillion Joules per second. 250 trillion Joules per second is equivalent to detonating four Hiroshima atomic bombs per second, or two entire hurricane Sandy's per second. 90% of those 250 trillion J/s go into the ocean. All this heat has to go somewhere, it's not radiating outwards (that's what's already included in this calculation). The ice melting shouldn't surprise us at all.

[Neven]

Even if we all know it's coming, it's still going to be surprising/astonishing to witness the moment when conventional wisdom goes out the door and the ice melts, no matter what the weather conditions are. Again, I'm not convinced this will be the year that happens. But you never know. I do expect something to happen, ie some of the ice to go despite the weather.

Once the piggy bank ice is gone (Baffin and Kara mainly), we'll see if there is a stall or not. Around this same period, back in 2012, I remember the decline didn't slow down when the weather turned. That was such a moment of astonishment, even though it made perfect sense.

But again, just like last year, I think it's safe to say that the Arctic dodged a bullet. Was it the snow on land and ice this time? Is there some negative feedback? Or will that disaster melting season come sooner or/than later, as long as there's no real recovery?

[JayW]

Looks "melty" according to this.
https://ads.nipr.ac.jp/vishop/#/monitor

[Hyperion]

I've been fannyin around with attempts to group what little visible stuff there is on worldview into saneish buckets to give a bit of a grip on what actually is there under the clouds and limited resolution of microwave data acquisition processes.
No scientific repeat-ability here. completely at the mercy of what image enhancement and bias I might have a whim to invoke in trying to filter out clouds and weight the value of slush between obviously coherent solid bergs. What relative value should I try to impose on slush fill between them? Heres an example from 85 nth last week in a mostly gap in the clouds at about 85 nth of fjl. I grayscaled. upped contrast and brightness and after experimenting with this a few times settled on a heavy handed sharpening filter to avoid losing all the between floes slush. Bucketing binary fashion into ice and not is obviously cheap and nasty and neither consistently repeatable in any sort of comparable fashion. Or reputable as any kind of standardized method considering the huge variability of cloud fog and slush density and thickness you gotta look at. So pure experiment really. and a n excuse to play with the rasp-pi and risc-beeb-basic that i was always jealous of my early eighties mates who had the  fortune to be equipped with. Damn I forgot how finicky and resource limited computers back then actually were. I haven't coded for years and memory and processing speed are like trillions of times what I used to enjoy. Anyway. any attempt at a fair count on reasonably clear images is getting me between 15 and 30% coherent floe area. The rest ranging from undeniable open water to slushfields of highly speculative chunk-size, density and longevity.
IMO generous concentration figure from this relatively heavy handed but imo fairly balanced mauling 0.415. and recognizable floe area here and everywhere else I've spanked with this ham 15-25%

[Cid_Yama]

I think we are in Daiquiri times . . .

Make mine a frozen Margarita.   

[Tor Bejnar]

Hyperion,
I like what you are attempting.  I would 'wish', somehow, that the larger floes (maybe 10-20 percent of total area, depending on size criteria) could be made entirely ice-white.  Right now, they are all melty-black speckled, some approaching half-black.  I think this exaggerates how advanced the melt is.

[Wipneus]

A century extent drop makes 2017 extent lowest for the day, just below 2016 and 2012. Kara and Greenland Sea contribute most.

Update 20170720.

Extent: -114.6 (-56k vs 2016, -327k vs 2015, -418k vs 2014, -238k vs 2013, -35k vs 2012)
Area: -56.1 (+373k vs 2016, -77k vs 2015, -380k vs 2014, -199k vs 2013, +135k vs 2012)
 
The details (in 1000 km²):


Extent:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                   -5.9                   -11.6                    -5.5
               Kara Sea             Barents Sea           Greenland Sea
                  -38.6                    -0.3                   -41.4
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                   -8.8                    -0.1                    -1.0
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                   -7.2                     2.4                     3.7
             Bering Sea          Sea of Okhotsk            Total Extent
                    0.0                    -0.1                  -114.6

Area:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                   16.6                   -18.2                    10.9
               Kara Sea             Barents Sea           Greenland Sea
                  -17.0                    -3.8                   -26.5
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                  -22.2                    -0.1                     0.1
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                    7.9                    -1.3                    -2.5
             Bering Sea          Sea of Okhotsk              Total Area
                    0.0                     0.0                   -56.1


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

[Wipneus]

Animation compares the ice concentration in the Greenland Sea with 2016. You can see the mobile ice melting away quick. Less fast ice on the East Greenland coast and more ice around Svalbard in 2017.

Click to start the animation.

[Csnavywx]

Even if we all know it's coming, it's still going to be surprising/astonishing to witness the moment when conventional wisdom goes out the door and the ice melts, no matter what the weather conditions are. Again, I'm not convinced this will be the year that happens. But you never know. I do expect something to happen, ie some of the ice to go despite the weather.

Once the piggy bank ice is gone (Baffin and Kara mainly), we'll see if there is a stall or not. Around this same period, back in 2012, I remember the decline didn't slow down when the weather turned. That was such a moment of astonishment, even though it made perfect sense.

But again, just like last year, I think it's safe to say that the Arctic dodged a bullet. Was it the snow on land and ice this time? Is there some negative feedback? Or will that disaster melting season come sooner or/than later, as long as there's no real recovery?

I really think it has to do with the flip back to a solid +PDO/IPO. That tends to focus ridging away from the pole and weaken the Aleutian low in summer, favoring a +AO state. The only time it could really hurt is during and after a strong Nino (which happens more often in a +PDO state).

The 2007-2012 period was dominated by a moderate to strong -PDO and was Nina dominant. -PDO/2nd-year -ENSO tends to be very bad for the arctic.

Eventually it will get warm enough or a big enough Nino will strike that it'll wipe out ice cover regardless -- but my hunch here is that we might have to wait for that piece of natural variability to flip. It might take 10 years or more to do so. But once it does, it might result in a startlingly fast decline.

[Thawing Thunder]

Hyperion,
I like what you are attempting.  I would 'wish', somehow, that the larger floes (maybe 10-20 percent of total area, depending on size criteria) could be made entirely ice-white.  Right now, they are all melty-black speckled, some approaching half-black.  I think this exaggerates how advanced the melt is.

Yes, this is a very valuable contribution. But Hyperion should not push the contrast too hard. I have a lot of experience with Photoshop and alike: These images after all are pretty low resolution 8bit – there's a point of no return where you loose more than you gain (which, by the way, somehow fits our topic here  ).

[Hyperion]

Hyperion,
I like what you are attempting.  I would 'wish', somehow, that the larger floes (maybe 10-20 percent of total area, depending on size criteria) could be made entirely ice-white.  Right now, they are all melty-black speckled, some approaching half-black.  I think this exaggerates how advanced the melt is.

Yes, this is a very valuable contribution. But Hyperion should not push the contrast too hard. I have a lot of experience with Photoshop and alike: These images after all are pretty low resolution 8bit – there's a point of no return where you loose more than you gain (which, by the way, somehow fits our topic here  ).

Sure. this was just a couple hours of trivial experimentation. It wouldn't be too hard to code a custom filter that did a pass where pixels that were surrounded by high luminosity ones were translated as pure white on a second image. If you tiled it you may be able to estimate rubble concentrations by luminousity comparisons with coherant nearby floes. You could probably also use hue and luminosity to mark melt ponds. It'd be nice to scan terra, aqua, and suomi imagesets with an algorithm that compared their infra red bands to automatically pick out holes in the cloud cover, and combine all the visible windows from the three. But by the time we got very far with it there would probably be no Ice left to look at. Be lovely to be able to estimate total floe area, meltpond area, rubble area for the whole arctic,  and by building up a picture of the whole basin over 1-2 weeks, tracking floe movements .... Lots of fun. But perhaps putting the energy into damage limitation might be better. This year or five from now is big trouble for all life on earth. We know its going. We need to be putting brakes on it and working out how to get it back. Much harder than if we'd acted rather than ostriching in the first place. But Doable.

[Wipneus]

The race in extent continues. Area now in lowest 4th place.

Update 20170721.

Extent: -86.6 (-72k vs 2016, -304k vs 2015, -427k vs 2014, -207k vs 2013, -36k vs 2012)
Area: -56.7 (+306k vs 2016, +24k vs 2015, -356k vs 2014, -173k vs 2013, +307k vs 2012)
 
The details (in 1000 km²):


Extent:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                   -9.5                   -22.8                   -18.1
               Kara Sea             Barents Sea           Greenland Sea
                  -12.6                    -3.4                   -10.0
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                  -10.9                     0.1                    -7.2
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                    2.6                     8.7                    -3.3
             Bering Sea          Sea of Okhotsk            Total Extent
                   -0.2                     0.2                   -86.6

Area:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                  -75.2                    14.7                     2.9
               Kara Sea             Barents Sea           Greenland Sea
                   -8.5                    -5.0                    15.6
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                  -10.7                     0.1                    -5.0
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                    3.6                     0.5                    10.6
             Bering Sea          Sea of Okhotsk              Total Area
                   -0.2                     0.1                   -56.7



Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

[greatdying2]

Sure. this was just a couple hours of trivial experimentation. It wouldn't be too hard to code a custom filter that did a pass where pixels that were surrounded by high luminosity ones were translated as pure white on a second image. If you tiled it you may be able to estimate rubble concentrations by luminousity comparisons with coherant nearby floes. You could probably also use hue and luminosity to mark melt ponds. It'd be nice to scan terra, aqua, and suomi imagesets with an algorithm that compared their infra red bands to automatically pick out holes in the cloud cover, and combine all the visible windows from the three...

I'm surprised that there isn't already someone working on this type of thing at a scientific institution... or is there?

[Wipneus]

The ice in Kara shows how fast it can disappear suddenly.

[magnamentis]

The ice in Kara shows how fast it can disappear suddenly.

yep, the thinner the ice will be over great areas the more often this will happen in various places and i still expect something like that this year, let's see.

[jdallen]

The ice in Kara shows how fast it can disappear suddenly.

The ice generally really is following my expectations.

[Wipneus]

Hmm, rather slow day?

Update 20170722.

Extent: -25.0 (+34k vs 2016, -182k vs 2015, -408k vs 2014, -132k vs 2013, +65k vs 2012)
Area: -43.1 (+376k vs 2016, +156k vs 2015, -273k vs 2014, -135k vs 2013, +254k vs 2012)
 
The details (in 1000 km²):


Extent:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                    0.6                   -11.5                    -8.6
               Kara Sea             Barents Sea           Greenland Sea
                    6.8                    -1.2                   -13.9
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                    0.3                     0.0                    -5.7
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                    2.9                     7.3                    -1.6
             Bering Sea          Sea of Okhotsk            Total Extent
                    0.2                    -0.5                   -25.0

Area:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                   -4.2                     3.5                   -11.2
               Kara Sea             Barents Sea           Greenland Sea
                   -0.2                    -1.6                    -8.8
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                   -0.1                     0.0                    -5.3
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                   -5.9                     4.1                   -13.1
             Bering Sea          Sea of Okhotsk              Total Area
                    0.1                    -0.4                   -43.1


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

[deconstruct]

I'm surprised that there isn't already someone working on this type of thing at a scientific institution... or is there?

The Canadian Ice Service produces a weekly composite image that tries to show as much of the arctic cloud-free in that period of time. The image is generated every wednesday for the preceeding week.

http://www.ec.gc.ca/Glaces-Ice/default.asp?lang=En&n=DFFA2648-1
http://ice-glaces.ec.gc.ca/cgi-bin/getprod.pl?prodid=MODISCOM-F&wrap=1&lang=en

[Neven]

Over on the blog, back in 2012, there was a commenter who then used those images and tried to make them even more cloud-free (see here and here, for instance)

[Thawing Thunder]

The Canadian Ice Service produces a weekly composite image that tries to show as much of the arctic cloud-free in that period of time. The image is generated every wednesday for the preceeding week.

That's great to know! Though this image is lacking resolution. I tried something similar with a part of the Arctic, using world view images. Much more detail. You can see it in the melt thread or on flickr in full resolution:

https://www.flickr.com/photos/153006036@N06/35995358361/in/dateposted-public/

[Wipneus]

The 53k extent loss was mainly in the Greenland Sea. Meanwhile area lost a lot more, also in the Greenland Sea, but also ESS and CAB.

Update 20170723.

Extent: -53.4 (+107k vs 2016, -128k vs 2015, -418k vs 2014, -128k vs 2013, +114k vs 2012)
Area: -172.1 (+275k vs 2016, +53k vs 2015, -341k vs 2014, -260k vs 2013, +197k vs 2012)

The details (in 1000 km²):


Extent:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                   -3.1                    -4.7                     4.9
               Kara Sea             Barents Sea           Greenland Sea
                    7.2                    -6.4                   -40.1
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                   -7.0                    -0.1                    -1.5
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                    3.4                     1.6                    -7.7
             Bering Sea          Sea of Okhotsk            Total Extent
                    0.3                    -0.1                   -53.4

Area:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                  -39.7                   -32.4                    -7.4
               Kara Sea             Barents Sea           Greenland Sea
                   -0.1                    -6.6                   -61.6
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                   -0.2                    -0.1                    -1.9
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                    3.1                   -19.4                    -6.0
             Bering Sea          Sea of Okhotsk              Total Area
                    0.5                    -0.1                  -172.1


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

[Shared Humanity]

Transport through the Fram can start up anytime but, if it doesn't soon, we seem to be heading to a nearly ice free Greenland Sea.

[Tigertown]

Transport through the Fram can start up anytime but, if it doesn't soon, we seem to be heading to a nearly ice free Greenland Sea.

26th-28th has some reverse flow, but the 25th(not long enough to get things going) and 29th onward look like it may be possible.
CLICK IMAGE

[Wipneus]

Serious melting resumes....

Update 20170724.

Extent: -97.7 (+63k vs 2016, -140k vs 2015, -441k vs 2014, -214k vs 2013, +134k vs 2012)
Area: -148.8 (+87k vs 2016, -43k vs 2015, -442k vs 2014, -322k vs 2013, +129k vs 2012)
 
The details (in 1000 km²):


Extent:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                   -5.8                   -15.5                   -11.8
               Kara Sea             Barents Sea           Greenland Sea
                   -4.1                    -3.2                   -10.1
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                  -23.2                     0.0                    -1.7
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                   -7.7                    -5.8                    -9.4
             Bering Sea          Sea of Okhotsk            Total Extent
                    0.0                     0.6                   -97.7

Area:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                  -79.8                   -16.1                   -23.6
               Kara Sea             Barents Sea           Greenland Sea
                   -8.0                    -2.9                    -4.5
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                  -30.0                     0.0                     1.5
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                  -14.2                    23.0                     5.5
             Bering Sea          Sea of Okhotsk              Total Area
                   -0.2                     0.6                  -148.8


Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

[Cid_Yama]

I can't thank you enough.

[greatdying2]

CAB area is finally starting to fall in a serious way.

[Tor Bejnar]

In Wipneus's Delta Map, I note a broad area in the Beaufort Sea with the concentration in the low-concentration ice increasing (>7%) and at its edge concentration dropping below 15%.  This looks like a consolidation process: draw the scattered floes in to the pack and give up the edges to ice-freedom.

I presume this is an example of "high pressure scatters and low pressure gathers" (Now-cast from Climate Reanalyser via ASIG)

[greatdying2]

In Wipneus's Delta Map, I note a broad area in the Beaufort Sea with the concentration in the low-concentration ice increasing (>7%) and at its edge concentration dropping below 15%.

Perhaps, but have a look back at the preceding day's map: this zone is actually blinking (up, down...). Also have a look at these gifs:
http://forum.arctic-sea-ice.net/index.php/topic,1834.msg122226.html#msg122226 .
At least in the zone dominated by the Beaufort gyre over the period shown (5 days last week), it looks like the pack is getting pushed south and melting, not consolidating.

[Wipneus]

The -138k area drop brings area numbers more in line with those of extent: 2017 is very close to 2012 and 2016.
 
Update 20170725.

Extent: -72.3 (+39k vs 2016, -129k vs 2015, -446k vs 2014, -239k vs 2013, +17k vs 2012)
Area: -137.7 (+19k vs 2016, -61k vs 2015, -504k vs 2014, -359k vs 2013, +15k vs 2012)

The details (in 1000 km²):


Extent:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                    1.3                   -22.9                   -15.2
               Kara Sea             Barents Sea           Greenland Sea
                   -5.6                     3.1                   -12.2
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                  -24.3                     0.0                    -2.5
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                   -1.3                     0.6                     6.9
             Bering Sea          Sea of Okhotsk            Total Extent
                   -0.4                     0.1                   -72.3

Area:
   Central Arctic Basin       East Siberian Sea              Laptev Sea
                  -48.0                   -11.5                   -20.2
               Kara Sea             Barents Sea           Greenland Sea
                   -3.5                     2.5                    -6.1
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                  -18.0                     0.0                     1.2
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                   -4.1                   -22.9                    -6.8
             Bering Sea          Sea of Okhotsk              Total Area
                   -0.3                     0.0                  -137.7



Delta map attached: red/blue means the concentration went below/over the 15% cut-off. Reddish/bluish means the concentration decreased/increased by more than 7%.

The detail shown is north and east of Svalbard where some open water between the ice floes can now resolved by the hi-res 3.125km sea ice concentration map.

[gerontocrat]

The -138k area drop brings area numbers more in line with those of extent: 2017 is very close to 2012 and 2016.
 
Update 20170725.

Extent: -72.3 (+39k vs 2016, -129k vs 2015, -446k vs 2014, -239k vs 2013, +17k vs 2012)
Area: -137.7 (+19k vs 2016, -61k vs 2015, -504k vs 2014, -359k vs 2013, +15k vs 2012)

A big divergence from Jaxa  extent data, which says 2017 extent on July 25 is 326 k less than 2012. Is it because Jaxa has a 200k+ extent drop on the 24th July 2012?
Jaxa data is that 2017 goes into a sulk while 2012 went doo-lally.