Home brew AMSR2 extent & area calculation

[jdallen]

Judging from models, pretty much everything going out the Fram is MYI right now.  Not much new ice left on this side of the basin to export.

Anecdotally, I'd put the export at about 10K KM2/day.

[ghoti]

The newly placed 2014D buoy is heading for the Fram at a good clip so far. We'll see how long it takes to get there.

http://imb.crrel.usace.army.mil/2014D.htm

[Jim Hunt]

The newly placed 2014D buoy is heading for the Fram at a good clip so far. We'll see how long it takes to get there.

I'm not stalking you ghoti, I promise! See also http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/winter-201314-imbs/#2014D which reveals:

[ghoti]

I actually posted that to prod you into showing your buoy tracking! 

[Wipneus]

Bad ice in the Barents Sea, and the ice up to the pole does not look much healthier.

[Wipneus]

Extent and area are bouncing a bit back from the cliff drop in the past days. Exceptions are the ESS and Laptev Sea. This is why:

(click and the pic will animate)

[icefest]

That fast ice isn't looking to flash either.

Is the higher absorption due to water pooling on top, or due to decreased thickness leading to increased translucency?

[werther]

Morning Icefest,
I've been looking at the Laptev fast ice a lot spring '12, '13 and now. Ever since I noticed a 'scintillation' on the ice which could possibly be a sign of methane releases and their mark on the ice. This year no sign of these marks can be seen.
It could be a sign of a thicker than usual snow cover. In that case, the greys on Wipneus' graph might indicate the snow pack getting wetter. The same for the yellows on the UniBremen map.

This fits with temperature records, showing +2 and +4 dC in Tiksi for 20-21 April.

[icefest]

Thank you Werther.

[Wipneus]

Ice is on the move everywhere.

(click the pic to animate)

[jdallen]

Ice is on the move everywhere.

Wow... Isn't it unusual for the Amundsen Gulf to break up like that this early? Doesn't an ice bridge normally form at the exit to the Beaufort?  Seems like conditions have blown right past that stage.

[jdallen]

Unusual but not extraordinary. Pity so much of lance Modis is missing.

Same dates, approximately.
2009 - solid
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r05c02.2009115.terra
2010, not so much...
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r05c02.2010115.terra
Today:
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r05c02.2014115.terra

[ChasingIce]

extraordinary weather has extraordinary results for ice. 

[jdallen]

extraordinary weather has extraordinary results for ice.

Indeed.  The Bering has already mostly disintegrated into a slush of nilas and disconnected floes.

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r06c03.2014115.terra.250m

[Yuha]

It seems that the Amundsen Gulf never properly froze up this winter.
See for example these MODIS Terra images from Feb. 19 and Mar. 15.

[Wipneus]

Update 20140430.

Net extent decreased a little, with area a larger increase. We are still in early spring where freezing conditions exist in the North (so leads get covered with thin ice) and melting in the peripheral regions.
Today's images show two regions where you may speak of a "torch".


Extent: -7.3 (+52k vs 2013)
Area: +73.9 (+115k vs 2013)

The details (in 1000 km²):

Extent:
           Arctic Basin       East Siberian Sea              Laptev Sea
                   -1.6                     2.2                    -2.0
               Kara Sea             Barents Sea           Greenland Sea
                    0.6                     5.9                    -3.0
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                  -20.0                    -0.8                     2.0
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                   -0.7                     6.3                    10.3
             Bering Sea          Sea of Okhotsk            Total Extent
                  -10.8                     4.2                    -7.3

Area:
           Arctic Basin       East Siberian Sea              Laptev Sea
                   15.8                    -2.4                   -18.6
               Kara Sea             Barents Sea           Greenland Sea
                   -1.6                    -0.3                    -0.6
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                   -0.1                    -0.6                    22.3
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                    2.2                    13.0                    15.5
             Bering Sea          Sea of Okhotsk              Total Area
                   24.0                     5.4                    73.9

[Pmt111500]

Noting that your (Wipneus) graph on PIOMAS volume loss has exposure on http://www.dailykos.com/story/2014/05/01/1296055/-Climate-Change

[Frivolousz21]

The Bering is getting smacked.

The Beaufort gets totally back smacked next.

[Shared Humanity]

Wipneus.....Doesn't that view suggest the Bering is seeing more drift than melt?

[Wipneus]

Wipneus.....Doesn't that view suggest the Bering is seeing more drift than melt?

Indeed, the drift shows southern winds that in this time of year will enhance the seasonal melt.

[Wipneus]

Update 20140501.

As Shared Humanity observed yesterday drift is dominating over melt, yet the net figures are negative in the peripheral regions. As images I show the Bering Sea because the pattern is exactly the same as yesterday. Further Barents as an extreme example of lots of ice movements from which you can read the direction of the wind and a small negative total result in extent and area.


Extent: -85.6 (+23k vs 2013)
Area: -52.2 (+148k vs 2013)


The details (in 1000 km²):


Extent:
           Arctic Basin       East Siberian Sea              Laptev Sea
                   -5.3                     0.7                    -4.1
               Kara Sea             Barents Sea           Greenland Sea
                   -1.2                   -10.9                    -2.7
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                   -8.3                    -0.6                     1.2
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                   -2.5                     1.3                    -1.1
             Bering Sea          Sea of Okhotsk            Total Extent
                  -46.0                    -6.3                   -85.6

Area:
           Arctic Basin       East Siberian Sea              Laptev Sea
                   27.2                    22.8                    -9.0
               Kara Sea             Barents Sea           Greenland Sea
                  -13.8                   -14.9                     3.4
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                  -17.6                    -1.6                    10.0
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                   -6.8                     7.3                    -2.7
             Bering Sea          Sea of Okhotsk              Total Area
                  -48.9                    -7.6                   -52.2

[Wipneus]

The march to Fram Strait continues although some ice seems to take a wrong turn and go east of Svalbard.

(click the picture to animate)

[crandles]

The march to Fram Strait continues although some ice seems to take a wrong turn and go east of Svalbard.

Yes it is MYI north of Greenland heading for Fram and lots of ice also pushed past Franz Josef. Barents has gained 200k since just before mid March. This will melt out as always but I think the important observation is where is it coming from? I think that Laptev and ESS are being caused to have very thin ice near coasts which will rapidly melt and get albedo feedback going.

Compare Laptev in

vs

[Wipneus]

In this animation of the last two weeks in Kara the ice mobility is obvious. As the winds have constantly blown from the NE quadrant, the ice has been confined in the Kara region. I can only imagine what happens when a warm southerly will blow.

(click on the picture for the animation)

[Wipneus]

The big crack in the East Siberian Sea is still there, it seems to separate the mobile ice in the Central  Arctic (and other) regions from a big piece of steady (some cracks are visible near the edge though) landfast ice in the ESS and the Laptev Sea.

(must click the picture to start animation)

[werther]

Interesting, Wipneus.
The fastice seems to be limited to the 30 m deepness line on the broad continental shelf. Maybe the Arctic Boundary Current has no effective room to get on the shelf further south?
But it does pass south of Wrangel.

[jdallen]

Interesting, Wipneus.
The fastice seems to be limited to the 30 m deepness line on the broad continental shelf. Maybe the Arctic Boundary Current has no effective room to get on the shelf further south?
But it does pass south of Wrangel.

I suspect currents are playing more of a role than they have previously.  With the system closer to threshold, those inputs will start having more visible influence.

[Shared Humanity]

Interesting, Wipneus.
The fastice seems to be limited to the 30 m deepness line on the broad continental shelf. Maybe the Arctic Boundary Current has no effective room to get on the shelf further south?
But it does pass south of Wrangel.

I suspect currents are playing more of a role than they have previously.  With the system closer to threshold, those inputs will start having more visible influence.

If a more fragile, mobile icepack means currents will have an increasing impact on the ice, what does our existing knowledge of Arctic currents suggest will be the ongoing  impact? I am interested not only in the surface currents but also the deeper currents which include the flow of North Atlantic waters into the Arctic.

[Wipneus]

In this animation of the Greenland and Barents Sea, the Fram Strait transport does not show any slow down. Once through, the ice seems to disintegrate quickly: not much gets past NE Greenland anymore.
In the Barents Sea the ice seems also to be in a disappearing act judging the last few frames.

(click the picture for the animation to start)

[werther]

Morning, Wipneus!
Your animation doesn't roll for me....

[Wipneus]

It should work now.

[Espen]

I wonder when the Belgica Bank / Norske Øer and Danmarkshavn fast ice complex gives in this season?

[LRC1962]

In this animation of the Greenland and Barents Sea, the Fram Strait transport does not show any slow down. Once through, the ice seems to disintegrate quickly: not much gets past NE Greenland anymore.

Wouldn't that because SST's in that area are heading into the 3C + mark? Also would indicate that the rebound of ice may not be that great because the ice created was very poor quality. Seems to me that by the end of 2012 almost all thick ice was gone.
http://earth.nullschool.net/#current/ocean/surface/currents/overlay=sea_surface_temp/orthographic=-72.38,89.47,573
http://neven1.typepad.com/.a/6a0133f03a1e37970b0176172539ed970c-pi
Creating thick ice is one thing. My question would be how long does 2-3M of new ice take to expel most of its salt and air? If it takes multiple years, then all that MYI we are seeing is little better then FYI. IMO from what we are seeing right now the MYI still has a lot of air and salt in it still making very weak.

In the Barents Sea the ice seems also to be in a disappearing act judging the last few frames.

The SST's in that area are warming fast in the last few days which means a lot of heat getting in and all that area has been hit by a lot of surface winds for the last week or 2 adding more 'heat'.

[jdallen]

In this animation of the Greenland and Barents Sea, the Fram Strait transport does not show any slow down. Once through, the ice seems to disintegrate quickly: not much gets past NE Greenland anymore.

Wouldn't that because SST's in that area are heading into the 3C + mark? Also would indicate that the rebound of ice may not be that great because the ice created was very poor quality. Seems to me that by the end of 2012 almost all thick ice was gone.
http://earth.nullschool.net/#current/ocean/surface/currents/overlay=sea_surface_temp/orthographic=-72.38,89.47,573
http://neven1.typepad.com/.a/6a0133f03a1e37970b0176172539ed970c-pi
Creating thick ice is one thing. My question would be how long does 2-3M of new ice take to expel most of its salt and air? If it takes multiple years, then all that MYI we are seeing is little better then FYI. IMO from what we are seeing right now the MYI still has a lot of air and salt in it still making very weak.

In the Barents Sea the ice seems also to be in a disappearing act judging the last few frames.

The SST's in that area are warming fast in the last few days which means a lot of heat getting in and all that area has been hit by a lot of surface winds for the last week or 2 adding more 'heat'.

The Barents has become an ice incinerator, fed by two conveyors feeding it from the Nova Zemla/Franz Joseph gap and the Svalbard/Franz Joseph gap respectively. 

The currents heading north from the Norwegian Sea do not have anywhere to "dive" and I suspect that makes the heat more available.  At +1 to +4 or 5C, that water will chew up the ice at 5-10CM/day, so once the ice progresses sufficiently into the Barents proper, it disappears promptly.

That's been true even in the middle of the winter this year, and part of why the thicker 2nd year and MY ice has been getting replaced by thinner lead ice; the ice heading into the Barents no longer hangs around to "cork" the bottle.

[Wipneus]

Torch in action in Laptev. No, I don't think it is real, but it is spectacular.

(click for animation)

[Frivolousz21]

That is amazing.

It's melt water on the ice.

[Neven]

I would think so too. I made animations of this area back in 2011, and remember the moment when things turn grey/blue.

[jdallen]

I would think so too. I made animations of this area back in 2011, and remember the moment when things turn grey/blue.

DMI and Climate Reanalyzer both agree that it's warm enough, with more heat coming north across Siberia.

[Frivolousz21]

I would think so too. I made animations of this area back in 2011, and remember the moment when things turn grey/blue.

lol, except that was day 158.

It's day 143.


Looking at the models even with them backing off the dipole anomalies that area should melt very quickly this year.

[Yuha]

Torch in action in Laptev. No, I don't think it is real, but it is spectacular.

Could it be soot from Siberian forest fires?

[Frivolousz21]

Torch in action in Laptev. No, I don't think it is real, but it is spectacular.

Could it be soot from Siberian forest fires?

No.

[Jim Hunt]

Something certainly seems to be going on. Aqua 7/2/1 this morning:

[werther]

Underlining the special attraction the Southern Laptev Sea almost always provides, we now have posts on two overlapping threads.
I suggest we stick to the 2014 Melt season-thread to follow this and leave this fine thread to comment on the calculations and presentations that Wipneus provides. For melt news, we can always hop over to the other thread. OK?

[lanevn]

Could it be soot from Siberian forest fires?

less distant shoot of Siberian forest fires.

Looks like at 1:05 who were in burning car really got that award (.

[Wipneus]

It is interesting to see how different microwave sea ice concentration algorithms show the "Laptev Torch".
Here is a comparison between Jaxa's Bootstrap algorithm on a 10km grid and the ASI algorithm, calculated by Uni Hamburg on their 3.125 km grid.

The main difference between the algorithm is the use of the AMSR2 89GHz band while the Bootstrap algorithm uses the 37GHz band and below. This makes the ASI algorithm more sensitive to water vapor and liquid water in clouds. It is rather insensitive to the particular condition of the ice. I have no idea what the influence of smoke is, I cannot rule that out.

[Shared Humanity]

Wipneus...

Obviously, there is more detail in the UHamburg image. Is it real? Is it actually providing a more accurate assessment and , thus, evidence of melt where Jaxa cannot?

[Wipneus]

Wipneus...

Obviously, there is more detail in the UHamburg image. Is it real? Is it actually providing a more accurate assessment and , thus, evidence of melt where Jaxa cannot?

Resolution is real. Accuracy is something else. All algorithms detect water/ice fairly well, treating melt ponds as water. UH has some trouble with the atmosphere, "Nasa Team" (NSIDC uses this algorithm) is affected by different surface conditions. Bootstrap as used by Jaxa is quite well balanced and I think that considering ice concentration, it is the most "accurate" in the images above.

[Wipneus]

Data  for last weekend are still missing, therefore just a short animation of the Fram corner. Movements seem to be minimal (some just north of Greenland) but a favorable wind would change that fast, the pack looks in a bad state.

BTW, I will be disconnected after this and get a temporary internet connection later. In case there are no updates tomorrow that is probably the cause.

[seaice.de]

It is interesting to see how different microwave sea ice concentration algorithms show the "Laptev Torch".
Here is a comparison between Jaxa's Bootstrap algorithm on a 10km grid and the ASI algorithm, calculated by Uni Hamburg on their 3.125 km grid.

The main difference between the algorithm is the use of the AMSR2 89GHz band while the Bootstrap algorithm uses the 37GHz band and below. This makes the ASI algorithm more sensitive to water vapor and liquid water in clouds. It is rather insensitive to the particular condition of the ice. I have no idea what the influence of smoke is, I cannot rule that out.

The darker areas (decreased ice concentration) in the ASI results are probably due to surface melting, see e.g. http://www.seaice.de/Roesel_IEEE_2012.pdf

I can not rule out that enhanced surface melting is induced by soot.

[Wipneus]

Melting now starting seriously?

Update 20140610.

Extent: -145k8 (-381k vs 2013)
Area: -156k5 (-313k vs 2013)

Most of the decline are caused in Greenland Sea, Hudson and Baffin Bays. On the Pacific side Chukchi makes a moderate contribution. Further a the decrease of CAB-area is notable.

The details (in 1000 km²):


Extent:
           Arctic Basin       East Siberian Sea              Laptev Sea
                   -3.7                     2.3                     3.2
               Kara Sea             Barents Sea           Greenland Sea
                   -9.4                    -9.1                   -67.7
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                  -15.2                     0.2                   -31.3
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                   -3.5                    -0.4                   -10.6
             Bering Sea          Sea of Okhotsk            Total Extent
                   -0.5                    -0.3                  -145.8

Area:
           Arctic Basin       East Siberian Sea              Laptev Sea
                  -50.7                     5.5                     4.0
               Kara Sea             Barents Sea           Greenland Sea
                   -3.9                    13.7                   -64.2
Baffin/Newfoundland Bay            St. Lawrence              Hudson Bay
                    2.6                     0.2                   -56.7
   Canadian Archipelago            Beaufort Sea             Chukchi Sea
                    7.6                    -0.3                   -12.9
             Bering Sea          Sea of Okhotsk              Total Area
                   -1.0                    -0.3                  -156.5