The 2016 melting season

[werther]

....
In the meantime, it will be quite freightening if today's CB should be followed by others tomorrow etc. If so, a spectacular slide might be in pocket when the ECMWF forecast unfolds....

Within half a day my fear is realizing...
The 120K drop is in part the S Laptev Sea losing ice quickly and the wake of the latest Low in the Beaufort-sector. Today, the Low ends with pressing remaining ice into McClure Sound CAA, while high pressure is building up in the Chukchi-ESS sector.
Tomorrow, compaction starts N of the New Sib Islands.

The numbers? Tomorrow IJIS might produce lower than a CB. But thereafter the IJIS numbers will start reflecting the new weather pattern. Maybe saturday will produce the largest CB for the year.

[slow wing]

Yep, it's a bit of a wild forecast. Shown is the prediction 2 days away from ECMWF, with a 52 hPa pressure difference across the Arctic Basin and all the winds that would bring. A 979 hPa low in front of the Kara Sea is opposed by 1031 hPa in the Beaufort Sea.
http://www.tropicaltidbits.com/analysis/models/?model=ecmwf&region=nhem&pkg=z500_mslp&runtime=2016080300&fh=12&xpos=0&ypos=0
(The Arctic Basin is in the lower right - off centre as I wanted to keep the label in the top left.)

[Neven]

This is the most intense weather forecast I've seen in quite a while. We need friv to describe this one.

[F.Tnioli]

This is the most intense weather forecast I've seen in quite a while. We need friv to describe this one.

May be he's speechless? ><

[Reggie]

GMTA
Right after the word YIKES...Friv was the first thing that came to mind upon seeing that forecast

[Xyrus]

Yep, it's a bit of a wild forecast. Shown is the prediction 2 days away from ECMWF, with a 52 hPa pressure difference across the Arctic Basin and all the winds that would bring. A 979 hPa low in front of the Kara Sea is opposed by 1031 hPa in the Beaufort Sea...

Looks like someone is about to hit "Puree" on the Arctic ice pack.

[Gray-Wolf]

This is the most intense weather forecast I've seen in quite a while. We need friv to describe this one.

With the low concentration at the Greenland coast how much ice could be rammed up against the shore of Greenland/North shore CA? Even with the ice intact it could make quite a dent in the area/extent figures?

Then we have those tell tale 'yellow splodges' in the DMI sst plots for the pole? If the low concentration ice there gets put on a long spin cycle how much should we expect to survive?

[jdallen]

This is the most intense weather forecast I've seen in quite a while. We need friv to describe this one.

Climate Reanalyzer /GFS has 50+ KPH wind at the surface blowing NW across the Laptev *currently*.  Over the week it appears this stream will strafe to the NE ravaging the ESS and Pacific side CAB before setting up to blow from the Beaufort to the Fram along the CAA.

Throughout, local circulation aided by that will be shoving ice into warmer water along the Atlantic front.

It might be my bump up of my September SIE estimate was premature...

(Post script: Similarly worthy of note, the systems in question are dragging along very substantial plumes of moisture.  This will bring rain over the next few days to most of the Laptev and ESS/Chukchi/Pacific CAB. )

[echoughton]

Folks are wondering why the DMI is spiking...they call it unusual....above 80N can't do it when ice is present etc etc. Look over past years and it seems to happen all the time. Check back even into the 60s....spikes all over the place. This year seems to be much more right on the normal line.

http://ocean.dmi.dk/arctic/meant80n.uk.php

[seaicesailor]

Very disappointed with the fact that neither HYCOM ARC nor GLB are producing ice drift predictions since a few days ago. Precisely now.
Fortunately, OSI SAF (a department of EUMETSAT) has a new product in demo phase that consists of ice drift calculation from satellite measurements in the last 48h, working in summer too.
The map (drift from Jul 31 to Aug 2) does not show legend, the arrows represent the real displacement during the two days. Curiously, if the map is right, these last two days have seen  divergence in ESS and toward Fram/Atlantic side. With this drift map, the melting is being monumental, such that even in these conditions extent drops centuries.
For more info (data in netcdf open and all):
http://osisaf.met.no/p/ice/index.html#lrdrift-demo
 OSI-405-c: Sea Ice Motion Maps with 48 hours span, on 62.5 km Polar Stereographic Grid
Description: Next version of OSI-405-b product (see above), but with ice drift vectors in summer, and maps of uncertainties. This is a DEMONSTRATION product, not to be used for OPERATIONAL applications
Data used   SSMIS (91 GHz, DMSP F18), ASCAT (Metop-B), AMSR-2 (18.7 and 36.5 GHz, GCOM-W1)

Edit: The same product is in Neven's ASIG page, map generated by DMI.
http://ocean.dmi.dk/arctic/icedrift_anim/plots/icedrift.arc.d-00.png

[BornFromTheVoid]

The latest 7 day drop for the NSIDC extent (daily) is the 3rd largest this summer, at -786k. That melt rate is only surpassed by 2012 and 2000 for this time of year.

Given current conditions and the forecast, a mega melt week may be possible during the next few days, as warm southerlies move in over the ESS and and Laptev, both melting and compressing the fragmented ice cover, followed by strong cross polar winds toward the Atlantic, further increasing ice compression.

[Bruce Steele]

Seaicesailor, ITP  93  is still working . You could use it to get some calibration of the OSI - SAF drift map. Lat / Long is updated daily so you could calculate drift speed and compare to the length of the arrows in the OSI - SAF  map in the same area as the itp.
 It is also interesting that surface salinity for itp  93 is above 31 and  it looks like it is getting saltier although it is still well within the pack. Freshwater lens is currently missing.



http://www.whoi.edu/page.do?pid=148496

[Andreas T]

ITP89 is also still reporting position although no longer water data.
http://www.whoi.edu/page.do?pid=148096

[seaicesailor]

Seaicesailor, ITP  93  is still working . You could use it to get some calibration of the OSI - SAF drift map. Lat / Long is updated daily so you could calculate drift speed and compare to the length of the arrows in the OSI - SAF  map in the same area as the itp.
 It is also interesting that surface salinity for itp  93 is above 31 and  it looks like it is getting saltier although it is still well within the pack. Freshwater lens is currently missing.



http://www.whoi.edu/page.do?pid=148496

Thank you for the cue Bruce!
I can't compare with the precise data since I can't manipulate netcdf, but at least we can verify if indeed the arrows correspond to something close to the real drift vector or not

The segment of GPS coordinates is given by day 212.5 (31 July 12Z) and 214.5 (02 August 12Z). Jan 1 is day 0 and 2016 is lap-year, hope I got it right.
The resulting distance is 21 km and bearing 171°, almost South direction.
I put the path in Google Earth and compared with the arrow at the same approximate location of the OSI SAF map, same approximate scale. It compares ok. The arrows are too thick for representing anything precise, but I would say they intend to represent the calculated drift, and this may compare well to the measured drift by the buoy. But as I said, they should put a legend or explain what the arrows are!

[seaicesailor]

ITP89 is also still reporting position although no longer water data.
http://www.whoi.edu/page.do?pid=148096

Andreas, thanks, the distance covered by itp89 these two days was 13 km, bearing 42 deg, so no much point in trying to compare with the map in detail. However, the location of the buoy is in the Beaufort ice edge approximately North-East of the big block remains. The drifts shown in this region are smaller than around the itp93 and erratic. So the ipt89 data do not invalidate the product either.

[JayW]

Very disappointed with the fact that neither HYCOM ARC nor GLB are producing ice drift predictions since a few days ago. Precisely now.

Not sure how much this helps, as it only covers the "Pacific side", but NCEP has a polar ice drift model.

First attachment is the 168Hr forecast.
http://mag.ncep.noaa.gov/model-guidance-model-parameter.php?group=Model%20Guidance&model=polar&area=polar&cycle=20160803%2000%20UTC&param=ice_drift&fourpan=no&imageSize=&ps=model

Good gif making weather coming up.  Second attachment is 125 hour loop July29-Aug 3

I thought I'd zoom in a bit on the area northeast of Wrangel island.  Third attachment, Wrangel island in the lower left corner.  All using VIIRS imagery from the university of Alaska at fairbanks

http://feeder.gina.alaska.edu/search?utf8=✓&search%5Bsensors%5D%5B4%5D=1&search%5Bsensors%5D%5B3%5D=1&search%5Bfeeds%5D%5B5%5D=1&search%5Bstart%5D=&search%5Bend%5D=&commit=Search

Hopefully it all works.

[barry]

A contributor at another blog asked a question that got me wondering. Hope this thread is ok to put it to the board:

Which contributes most to Arctic sea ice melt, atmosphere or ocean?

My answer was atmosphere, considering all the ways that sea ice concentration could be affected by temps, winds, storms etc. I suspect that the answer could be different depending on whether you're talking about seasonal or long-term changes. I'm pretty green at this, so would appreciate better-informed views.

(Excellent blogs you host, Neven. I've been a long-time reader of ASIB and occasional dipper into ASIF)

[Tigertown]

Another century plus drop. Not sure how long it will continue to do this, but at this rate of loss, anything is possible. I still do not expect the Arctic to go ice free this year, but as for the record, it could be up for grabs, if only by a margin.

[jdallen]

1.5 Million KM2 of ugly.  Today's image from EOSDIS.  Wrangel in the upper left hand corner.

[budmantis]

Most of that 1.5 million km2 could be gone within a month, given the right weather conditions.

[Rob Dekker]

JayW, that "NE of Wrangel" animation is just scary.
That ice is gonna go, and with the current weather forecast, I think "a month" is a gross overestimate. That area is going to show some serious "flash melt" events in the coming week.

[werther]

Aww... minus 116K for a transition day. On which I didn't suspect the chain of CB's to be sustained...

Have to see on MODIS where that one came from. Probably Laptev- and Beaufort-sector. From what's available now, the High and Low are in position and winds are picking up to 'bite the bite'.

[Rob Dekker]

werther, Wipneus reported this on the AMSR2 thread :

Update 20160803.

Extent: -149.0 (-138k vs 2015, -686k vs 2014, -581k vs 2013, +69k vs 2012)
Area: -118.0 (-185k vs 2015, -998k vs 2014, -788k vs 2013, -240k vs 2012)
 
You will find the updated graphs in the top post

(extent losses in CAA (-37k), Laptev (-28k) and ESS (-27k)

[Thawing Thunder]

 ...

[Neven]

Awesome animation. 

[werther]

That's for sure, Neven!
TT, what's  fuelling it...let me guess...

[echoughton]

I love science!   

[seaicesailor]

HYCOM (ARC+CICE) has updated its drift forecasts, which makes for a colorful animation.
Note the impact on ESS in general. The bite is going to grow a lot.
But note also the export toward the Atlantic front. I estimate 100 km x 1000 km = 100,000 km2 of extent will go toward the front. This extent will be melting for some time, not inmediately.

[Thawing Thunder]

That's for sure, Neven!
TT, what's  fuelling it...let me guess...

100% solar.

[werther]

Then it is... good??

[F.Tnioli]

Then it is... good??

Depends on who's asking. Carrington event - solar storm of 1859, - was extremely very good for astronomers, in particular good mr. Carrington. But those telegraph operators shocked and burned alive? Not so good.

So, well, kinda same here - depends on who's asking.

[seaicesailor]

The elongated line of melt at Chukchi sea ice edge, north of Wrangel (and that hole along the line, way inside the pack toward the Pole) stays put in the same location after two weeks of agitated weather.
We'll see next week. It is a very interesting feature, due to ice melt/drift no other one remains as steady as this one.

[AbruptSLR]

Then it is... good??

Essentially, all of global warming (and associated Arctic sea ice loss) is fueled by solar power, it is just facilitated by anthropogenic GHGs.

[Gray-Wolf]

When I look at the navy model for drift I have to keep reminding myself of the state of the ice under that high forcing. Are we to see faster transport due to ice condition or are we to see swells generated and overwash/tumbling becoming an issue?

Also if we do see heavy weather and floes do get flipped will their base be darkened with algae so lowering albedo?( I know solar is low but would a sudden drop in albedo show enhanced melt for the time of year?)

What I'm trying to say is 'is this significantly different an event to similar ones over past years due to the highly fragmented pack?'

[RoxTheGeologist]

Then it is... good??

Essentially, all of global warming (and associated Arctic sea ice loss) is fueled by solar power, it is just facilitated by anthropogenic GHGs.

Well, it's all fission or fusion. Nuclear power is good for life.

[Gray-Wolf]

When we were getting ready for GAC12 didn't we already know that a sizable portion of the pack would be gone by seasons end even without the intervention of that storm? Are we not in an even worse position, as far as ice condition is concerned, today than then?

I know what is happening up there at present isn't as GAC12 but then the ice is worse and the ocean is warmer so should we not be looking at as similar level of losses over the coming week?

[Reggie]

@Thawing Thunder

I shamelessly stole that gif and posted it (with credit) on twitter.

[A-Team]

Here is the end game for 2015. The date range is 03 Aug to 15 Sept with a few dates omitted because of mask glitches and blank files at the UHH AMSR2 archive. The August 3rd still is appended below the 2015 animation.

I'll add 2013 and 2014 animations to this post as time permits. To get at 2016 -- which obviously hasn't happened yet so isn't in the archive -- the 'forward melting momentum' technique described earlier (where blueish color bins are gradually pushed up the palette) can be balanced by the 'backwards freeze-up momentum' (whitish color bins are pushed down the palette).

Applying this method to 2013-15 (which have known outcomes), confidence in the 2016 estimation can be assessed. The freeze-up of 2015 can be seen clearly towards the end of the animation below as the intermediate concentration blues whiten up.

http://forum.arctic-sea-ice.net/index.php/topic,762.msg85483.html#msg85483 more on methods

[seaicesailor]

Being a warmer Atlantic side in 2016, one can still notice from A-team's image above the great amount of transport to the atlantic front in the last 2-3 weeks (and more coming). All that diffuse area was not there in Sep 2015 or 3 weeks ago. It will be gone by September again. This transport has to be quantified in the future and compared to regular Fram export.

[seaicesailor]

The tongue of acvected warm air from East Siberia reaches the Pole as we speak.

[Paddy]

The August 3rd update of NSIDC's Arctic sea ice news makes for interesting reading, especially the EASE data on ice direction: http://nsidc.org/arcticseaicenews/

[Ice Shieldz]

Anyone have ideas about how all this compaction will effect the ice given its condition?  What end products would one expect?  Perhaps this needs to go under the thread Stupid Questions.

[seaicesailor]

Imo it is not a stupid question although I'd say that compaction is the effect.
I am as curious to know how it develops, especially how long it lasts.

[A-Team]

Here is the end game for 2013. The date range is 01 Aug to 25 Sept. Dates are in frame names if gif is downloaded. Details over at NW Passage #225.

[JayW]

August 1-4, roughly 80 hours.

Alaska in lower right

http://feeder.gina.alaska.edu/search?utf8=✓&search%5Bsensors%5D%5B4%5D=1&search%5Bsensors%5D%5B3%5D=1&search%5Bfeeds%5D%5B5%5D=1&search%5Bstart%5D=&search%5Bend%5D=&commit=Search

[slow wing]

Thanks to SeaIceSailor for post above with link to ice drift map:
http://osisaf.met.no/p/osisaf_hlprod_qlook.php?prod=LR-Drift-demo&area=NH.

Thanks also to OSI SAF for presenting the ice drift data.

Was trying to determine the spacing of the points on the grid.

Just eye-balling, there are about 17.3 grid units going from the North Pole to the 80 degrees latitude line, i.e. 17.3 units = 10 degrees latitude.
=> 1 grid unit = (10/90 * 10,000 km)/17.3 = 64 km.

I don't know why it isn't a round number & anyway the distance will presumably vary a bit over the gridded region.

However, if the drift direction happens to be vertical or horizontal and the arrow spans from its origin to the next grid point then presumably the ice has travelled about 64 km over the 2 days, which is 32 km/day. That would be a relatively large drift distance.

The most recent drift map shown is an active one:

[seaicesailor]

Thanks to SeaIceSailor for post above with link to ice drift map:
http://osisaf.met.no/p/osisaf_hlprod_qlook.php?prod=LR-Drift-demo&area=NH.

Thanks also to OSI SAF for presenting the ice drift data.

Was trying to determine the spacing of the points on the grid.

Just eye-balling, there are about 17.3 grid units going from the North Pole to the 80 degrees latitude line, i.e. 17.3 units = 10 degrees latitude.
=> 1 grid unit = (10/90 * 10,000 km)/17.3 = 64 km.

I don't know why it isn't a round number & anyway the distance will presumably vary a bit over the gridded region.

However, if the drift direction happens to be vertical or horizontal and the arrow spans from its origin to the next grid point then presumably the ice has travelled about 64 km over the 2 days, which is 32 km/day. That would be a relatively large drift distance.

The most recent drift map shown is an active one:

Slow Wing, thanks, it is a lot but I am not sure where are you saying this specific drift happens. They are very strong in general (forget about the anomalous ones obviously).
There's been a lot of transport towards Beaufort and Svalbard... that may explain the 'small' IJIS drop. This ice will be melting gradually.

[slow wing]

That drift distance is just an example. However, you can see similar distances happening on that map, e.g. along the longitude lines for 135 degrees West and also 135 degrees East. Arrows there can be seen to span the distance between adjacent grid points, indicating where the ice has travelled at least 64 km over the 2 days.

That's 64 km/48h = 1.3 km/h. Assuming a reasonable ice speed ratio of ~5% of the wind speed (it varies, as you know better than I do) that would be driven by moderately strong winds of say 25-30 km/h, as have indeed been observed over the past two days in those locations. So the ice drift there looks consistent with the winds shown by e.g. Nullschool.

[Thawing Thunder]

@Thawing Thunder

I shamelessly stole that gif and posted it (with credit) on twitter.

Feel free and go ahead - while I keep on stealing brainpower here 

[Darvince]

Here is the end game for 2013. The date range is 01 Aug to 25 Sept. Dates are in frame names if gif is downloaded. Details over at NW Passage #225.

I think the poor quality of the ice internal to the pack just shows how bad 2013 could have been if the weather that year had been conducive to melting, truly showing that weather is everything, especially now that the ice pack has entered such a poor state.