The 2020 melting season

[Viggy]

There are many similarities. Another. Until this summer, in 2011 there was a record of the earliest opening of the Northeast Passage.

Really cool graph and data! Hadn't seen that before!

And I don't disagree that 2020 has some similarities with 2011. But 2011 hit the brakes hard over the next few days and I don't see anything in the forecasts that predict a similar slowdown this year.

[Tealight]

I have two teaser images to share for a new NRT product coming soon to CryosphereComputing.tk

It shows why my SIPN forecast model doesn't expect a record melt like 2012. 2020 just keeps up with 2016 and 2019, though maybe not for long.

Unlike the AWP model this new Ice-Melt-Energy model only considers ice covered regions. Ice-free regions don't contribute any energy towards melting ice. A full explanation of the new model will soon follow in an extra topic.

[Neven]

David Schröder sent me the following:

Just submitted our prediciton based on June data: 4.3 (3.8-4.8 ) mill. km2.
This is just on the observed September trend line and larger than our May prediction (3.3-4.3 mill km2).
In spite of strong melt at the sea ice edge (current sea ice extent is lowest on record for this time of the year), pond formation slowed down during first half of June with air temperature not much above average in comparison to last 15 years.

Note: The accucary of our predictions based on May data has been higher then that based on June data over last 8 years.

Our prediction based on May data (3.8 ) was third lowest:
https://www.arcus.org/sipn/sea-ice-outlook/2020/june

[blumenkraft]

Amazing, Nico. Thank you very much.

[Jim Hunt]

A very unusual image:

https://GreatWhiteCon.info/2020/07/facts-about-the-arctic-in-july-2020/#Jul-15

[be cause]

Indeed  ^^.. a pole with measles .. the remaining larger floes covered in melt ponds ? b.c.

[Pagophilus]

And that would now be a crack visible and widening along the whole coast of northern Greenland, from the Atlantic to the Nares.

Holy guacamole.

Has this happened before?   In July?

The down button on year makes it easy to flip through the 20 years available on worldview and check.

Thank you, interstitial.  I did that (I do it fairly routinely) and saw nothing like this Greenland crack in July.  However, the area is often covered for long periods with clouds, so that is why I went to the experts.

[FishOutofWater]

Nico, I don't understand why there should be such a strong negative anomaly over the past 10 days in ice energy given the clear weather over the pole. I thought that clear skies, like we have had, at the time of peak insolation would lead to a strong positive anomaly. The energy balance is critical to how this year's melting season progresses and your curve shows the opposite from what I would expect. I'm very confused.

Heat going into the open water will have a strong effect on melting as long as the ice pack keeps on spinning and exporting ice into the water covered areas, but that won't apply to the central pack area from the pole to Greenland and the CAA.

Note the outgoing longwave radiation anomaly over the pole in the NOAA Physical Science Lab map. This map indicates clear skies and above normal incoming and outgoing radiation and by difference less cloud-reflected solar radiation than normal. This map shows that our inference, from the weather patterns, that more solar radiation than normal is reaching the surface is a good one.

[Aluminium]

A full explanation of the new model will soon follow in an extra topic.

Looks interesting and useful, though I don't understand something. TJ is almost nothing for the Arctic. Even 1000 TJ is almost nothing. 1 W/m² * 5M km² * 1 day = 432000 TJ.

[Pagophilus]

I have two teaser images to share for a new NRT product coming soon to CryosphereComputing.tk

It shows why my SIPN forecast model doesn't expect a record melt like 2012. 2020 just keeps up with 2016 and 2019, though maybe not for long.

Unlike the AWP model this new Ice-Melt-Energy model only considers ice covered regions. Ice-free regions don't contribute any energy towards melting ice. A full explanation of the new model will soon follow in an extra topic.

Hi Tealight, I respect and value your work and I guess I should await explanation of the new model.  However, the statement that " Ice-free regions don't contribute any energy towards melting ice." must refer just to the model, no?    (LATER EDIT -- I removed some of my excessive wordiness here, thanks Kassy)  You can look on this as puzzled ignorance if you like.  I look forward to learning more.

[kassy]

Off course that just refers to the model and piqued my interest too lets discuss that on Nico´s upcoming thread.

[FishOutofWater]

That image of stunning blue over the pole seems is pretty amazing. If there is a negative energy anomaly for melting at the same time as all that incoming short wave radiation we have written a lot of wrong things about the 2020 melting season on this thread. We need to get the physics right.

[Paul]

I think the similarities with 2011 are quite true in respect the large anticyclone compacted the ice but made extent quite small(as others said, it was record breaking at the time). If the weather changes, the ice starts to spread out and extent slows down but that comes with its own risks also as you start to lose the compaction of the ice and make it weaker in the interior. That is why others are saying a strong low could be bad news for the ice also.

Years with large dispersion tends to have stronger 2nd half's of the melt season because the interior of the pack is broken up and in theory, easier for the open water to make its way through and melt the ice. The supposed compaction of the ice is my only hope regarding this year that we won't break 2012s record but the chances of finishing 2nd lowest and perhaps comfortablely below 4 million is increasing day by day.

[Burnrate]

The difference a day makes

(13th and the 14th, bands 7-2-1 Terra/MODIS)

Click for gif:

[Pagophilus]

Not surprising that the data is causing such a stir. The graph is very much in uncharted territory.

JAXA ARCTIC SEA ICE EXTENT:  7,117,005 KM2 as at 14-Jul-2020

- Extent loss on this day 187k, 89 k more than the average loss on this day (of the last 10 years) of 98k,
- Extent loss from maximum on this date is 7,331 k, 917 k, 14.3% more than the 10 year average of 6,414 k.
- Extent is at position #1 in the satellite record
- Extent is  454 k LESS than 2019,
- Extent is  494 k LESS than 2016,
- Extent is  560 k LESS than 2012
- Extent is  686 k LESS than 2007

Crosspost of Gerontocrat's comments on extent and area thread, with thanks, as ever, to him and Juan for their indefatigable work, graphs and analyses.

Looking at Gerontocrat's and Juan's graphs on the thread, it seems that the loss of extent is about 4 days ahead of any previous year.  That is probably more significant at this time of year since we are still in the period of maximum effective solar insolation/albedo warming potential, and there are continuing clear skies.  It is also perhaps more significant when the ice is compacted, since the warm seas cannot get so readily at the ice right now to melt it and therefore insolation is paramount.  And yet those warm seas are still heating up, biding their time, waiting for a low.

Latest area is still at #3.  That should not be forgotten.     

[marcel_g]

I know this is a stupid thing to say but even if all the ice melts out wont it just come back in Winter like always and be like minus 40c.

Hudson does as do other areas year on year.

Is it the sea level rise that's the problem? The weather is already volatile.

Yes, the ice will reform, but it will be much slower, and will end up with much less volume by the end of the winter. My reasons: open water creates much more humidity, which traps much more heat, slowing losses into space, And this will prevent a strong polar vortex from forming, allowing Much extra warmth coming from lower latitudes. This could create a vicious cycle of thin weak ice in the winter, and early massive melt out in the summer, basically a rapid shift to a new sea ice paradigm, as well as new global weather patterns.

[Aluminium]

I visually compared this moment 2020 with 2019 using nullschool. In 2019 there was more clouds (clear sky/weak clouds: 20/50% in 2019 and 40/90% in 2020) and t850 was colder by 7°C in average.

[Pagophilus]

Nico, I don't understand why there should be such a strong negative anomaly over the past 10 days in ice energy given the clear weather over the pole. I thought that clear skies, like we have had, at the time of peak insolation would lead to a strong positive anomaly. The energy balance is critical to how this year's melting season progresses and your curve shows the opposite from what I would expect. I'm very confused.

Heat going into the open water will have a strong effect on melting as long as the ice pack keeps on spinning and exporting ice into the water covered areas, but that won't apply to the central pack area from the pole to Greenland and the CAA.

Note the outgoing longwave radiation anomaly over the pole in the NOAA Physical Science Lab map. This map indicates clear skies and above normal incoming and outgoing radiation and by difference less cloud-reflected solar radiation than normal. This map shows that our inference, from the weather patterns, that more solar radiation than normal is reaching the surface is a good one.

Also from Cryosphere Computing, using another model...  I realize it takes non-ice covered regions into account...
[/quote]

[Tealight]

.... TJ is almost nothing for the Arctic. Even 1000 TJ is almost nothing. 1 W/m² * 5M km² * 1 day = 432000 TJ.

You are right the unit is actually Exajoule (EJ). Damn km2 to SI unit conversion.

However, the statement that " Ice-free regions don't contribute any energy towards melting ice." must refer just to the model, no?

Yes, just in the current model. But on the maps you will see which Regions have continuously strong melt due to winds/currents pushing ice into warm waters. The Laptev Sea is not one of them.

For the central Arctic the daylight intensity drops in August to below melting conditions for a solid ice pack. Extensive meltponds can delay this point somewhat, but generally not as much as a very dispersed icepack as we have seen in 2012 and 2016. Currently the ice is just compacted against Canada/Greenland as a solid icepack. I wouldn't count on a strong melt in August.

By including heatloss to space the model returns the concept of negative Ice Melt Energy, also known colloquial as freezing.

[ArcticMelt2]

I think the similarities with 2011 are quite true in respect the large anticyclone compacted the ice but made extent quite small(as others said, it was record breaking at the time). If the weather changes, the ice starts to spread out and extent slows down but that comes with its own risks also as you start to lose the compaction of the ice and make it weaker in the interior. That is why others are saying a strong low could be bad news for the ice also.

Years with large dispersion tends to have stronger 2nd half's of the melt season because the interior of the pack is broken up and in theory, easier for the open water to make its way through and melt the ice. The supposed compaction of the ice is my only hope regarding this year that we won't break 2012s record but the chances of finishing 2nd lowest and perhaps comfortablely below 4 million is increasing day by day.

I completely agree. The fact that the ice pack is highly densified is also indicated by the fact that the net area of ice is not in the first place now.

The strong melting of the first half of July is largely due to the melting of the peripheral seas, the Hudson and Baffin. And soon these reserves will end.

By the way, today's picture is from 2011. At that time, there was only ice in the Baffin Sea, but not in the Hudson.

[GoSouthYoungins]

Laptev's bitten 125km in 5 days.

[Pagophilus]

Yes, just in the current model. But on the maps you will see which Regions have continuously strong melt due to winds/currents pushing ice into warm waters. The Laptev Sea is not one of them.

For the central Arctic the daylight intensity drops in August to below melting conditions for a solid ice pack. Extensive meltponds can delay this point somewhat, but generally not as much as a very dispersed icepack as we have seen in 2012 and 2016. Currently the ice is just compacted against Canada/Greenland as a solid icepack. I wouldn't count on a strong melt in August.

By including heatloss to space the model returns the concept of negative Ice Melt Energy, also known colloquial as freezing.

Thank you.  Very helpful to me.  Sounds like a record minimum would then depend on dispersal once August arrives.  Otherwise, the icepack holds together and doesn't melt too much further from the top at least. 

I am puzzled by the Laptev data you cite as the Laptev has melted out rapidly and the extent of Laptev sea ice continues to plummet.  Obviously I am missing something here...  Do you mean that there is relatively little sea ice being pushed into the Laptev by wind action?  Surely if ice were pushed in, it would melt quickly?

[uniquorn]

 osisaf, jul1/3-12/14
A lot of rotation, some signs of compaction (arrows pointing northward). Anything that rotates from ESS towards the Laptev disappears.

Wipneus regional extent, laptev and surrounding, jul13 jul14. CAB extent entering new territory.

[wdmn]

Admitting my ignorance, I don't get the comparisons to 2019. By this time last year melt momentum had clearly fizzled out, as many posters were saying at the time. This year it's been building and building without pause. If 2020 doesn't finish well below 2019, then I think this forum will collectively have to spend the freeze season reconsidering almost all of our assumptions about ice melt.

[ArcticMelt2]

Admitting my ignorance, I don't get the comparisons to 2019. By this time last year melt momentum had clearly fizzled out, as many posters were saying at the time. This year it's been building and building without pause. If 2020 doesn't finish well below 2019, then I think this forum will collectively have to spend the freeze season reconsidering almost all of our assumptions about ice melt.

This year is not at all like 2019. Then the ice melted strongly from Alaska - the earliest melting in the Barrow area. Now it is melting more from Siberia. 2020 is more like 2011 or 2014 but with some more power.

[ajouis]

Admitting my ignorance, I don't get the comparisons to 2019. By this time last year melt momentum had clearly fizzled out, as many posters were saying at the time. This year it's been building and building without pause. If 2020 doesn't finish well below 2019, then I think this forum will collectively have to spend the freeze season reconsidering almost all of our assumptions about ice melt.

This year is not at all like 2019. Then the ice melted strongly from Alaska - the earliest melting in the Barrow area. Now it is melting more from Siberia. 2020 is more like 2011 or 2014 but with some more power.

Not quite, there is much more atlantification and greater melt in the caa, really no recent season resemble each other, they all vary for at least one front in this time of year

[Milwen]

Big ice floes appeared north of Greenland today. 

[ArcticMelt2]

Admitting my ignorance, I don't get the comparisons to 2019. By this time last year melt momentum had clearly fizzled out, as many posters were saying at the time. This year it's been building and building without pause. If 2020 doesn't finish well below 2019, then I think this forum will collectively have to spend the freeze season reconsidering almost all of our assumptions about ice melt.

This year is not at all like 2019. Then the ice melted strongly from Alaska - the earliest melting in the Barrow area. Now it is melting more from Siberia. 2020 is more like 2011 or 2014 but with some more power.

Not quite, there is much more atlantification and greater melt in the caa, really no recent season resemble each other, they all vary for at least one front in this time of year

In the Barents and Kara Sea, in 2019, melting is almost the same as now. The main difference is on the Pacific side, less is the difference on the Siberian side.

[Milwen]

Also HYCOM 7 day forecast. Whole CAA is basically gone. 

[gerontocrat]

You are right the unit is actually Exajoule (EJ). Damn km2 to SI unit conversion.

For the central Arctic the daylight intensity drops in August to below melting conditions for a solid ice pack. Extensive meltponds can delay this point somewhat, but generally not as much as a very dispersed icepack as we have seen in 2012 and 2016. Currently the ice is just compacted against Canada/Greenland as a solid icepack. I wouldn't count on a strong melt in August.

I am glad to see that I am not the only one known to have screwed up with a conversion ratio. 

Attached is the graph of the Central Arctic Sea** concentration, which dropped like a stone and has since recovered. Note it was in 2016, not 2012 , when concentration dropped the most. 2016 minimum area was only 200k greater than 2012, while 2016 extent was 750k greater than 2012.
_________________________________________
Central Arctic Sea** - is the NSIDC defined area of 3.22 million km2, mostly above 80 North.
See map from MASIE attached.
The CAB as used by Wipneus in his PIOMAS output is 4.6 million km2

[ajouis]

arctic melt, I meant 2020 in comparison to 2011

[ArcticMelt2]

arctic melt, I meant 2020 in comparison to 2011

Have you seen the 2011 map of July 14th? The ice boundary in the Kara and Barents Sea is almost equal to today's. A little more ice is only in the Laptev Sea. This year is unique only on the Siberian side.

https://twitter.com/AlaskaWx/status/1283078129787957249

From @NSIDC Sea Ice Index v3, here are the regional #seaice extent rankings (since 1979) on July 13, 2020, 1=lowest, 42 highest. Impact of multi-month Siberian warmth is obvious. Only the Beaufort Sea and Hudson Bay are even close to average. #akwx #Arctic @Climatologist49 @ZLabe

[wdmn]

Looking over the regional seas data, without trying we lose 1.1m km2 in extent by the end of the month, leaving 2020 in a tie with 2019.

Moderate melt gets rid of 1.5m km2 by that date, leaving 2020 about 400k km2 head of second place 2019 as August begins.

[gerontocrat]

Those of you accessing NSIDC from https://nsidc.org/arcticseaicenews/sea-ice-tools/ need to know at the moment they have a problem....

They sent me an email.
_______________________________________________
Thank you for contacting NSIDC. Thank you for catching this issue. We have been experience issues with ingesting the data used for the sea ice analysis for the past two days, and are currently performing planned maintenance. However, it isn't immediately obvious what caused discrepancies in previous months.

I've sent a note the Arctic Sea Ice News and Analysis team, and I'll get back in touch with you shortly.

Best regards,
Nic

[Phoenix]

I have two teaser images to share for a new NRT product coming soon to CryosphereComputing.tk

It shows why my SIPN forecast model doesn't expect a record melt like 2012. 2020 just keeps up with 2016 and 2019, though maybe not for long.

Unlike the AWP model this new Ice-Melt-Energy model only considers ice covered regions. Ice-free regions don't contribute any energy towards melting ice. A full explanation of the new model will soon follow in an extra topic.

Excited to see a new product from you Nico !! A better quantitative understanding of the sea ice is certainly welcome. I look forward to reading the explanation and seeing how it holds up as a predictive tool.

Now that we understand the measurement unit is exajoule (1*10 ^ 18J), my understanding is that an exajoule is roughly the amount of energy required to melt 3 km3 of sea ice. In your explanation, perhaps you can let us know if the model is intended to be an indicator of prospective volume losses.

[Pagophilus]

Big ice floes appeared north of Greenland today. 

Yep.  Huge shards of fast ice breaking off.  Largest piece is about 50km across in its widest dimension.

[Frivolousz21]

I wrote out a very long post.  And after Reading the message I wrote out I realized that being so confrontational isn't productive.  So quickly:

1.  I think the notion that energy in the open Waters that are very warm next to the ice DOESN'T contribute quite powerfully to melting adjacent ice is utter rubbish.

2.  The conclusion that the ice is currently compact is utter rubbish.

There is open water all over the ice pack and huge melt lakes and ponds.

3. The melt momentum lacking compared to other years is utter rubbish.

I am getting triggered again.

These same talking points and bullshit rationalizing took place all over between 07-12 and it really hurt the quality of the group discussion.



Accordingly if 2020 finishes above 4 million km2 on jaxa.

Assuming 250-300k losses in Sept.

The rest of the main melt season will only lose 2.75 km2 BETWEEN now and Aug 31st .

That would be an average of 59,000km2 a day.

If the rest of July sees 1.25 mil km2 loss.  Which would be 78,000km2 a day.

And August would be:  48,000km2 per day.

And I can't buy that.

Below is todays modis. Absolutely massive area of sunny skies roasting the Arctic.

And the July 925mb temps so far which are straight insane.

SAY INSANE MELT MOMENTUM.

[pearscot]

Yeah, it's a bit off putting how all the sudden there's so much chatter about an imminent slowdown upcoming. I'm certainly expecting some days in the forecast with less melting than would be expected, but ONCE AGAIN, the central pack is about 2/3 clear. Other than the Beaufort, pretty much all regions are are in rough shape and I'm becoming increasingly more convinced of a direct correlation between the Greenland mega crack and Laptev warmth/open area (but I'll wait and watch more before saying more).

Either way, I still feel like July has a lot more in store and with the forecast maintaining the high I'm under the assumption that as the pack rotates, ice outside (south) of the 80 degrees latitude will be subject to both top and bottom melt as it's transported into the Laptev.

[Lord M Vader]

In a few days we"ll hopefully get the mid-monthly volume numbers from PSC. By then we should have a clue about what's going on.

One possible outcome for this season is a records low volume but not a record low extent number.

The key to beat 2012 should be Beaufort Sea and I'm not sure there will be enough melting there from now and up to the minimum.

[grixm]

2.  The conclusion that the ice is currently compact is utter rubbish.

There is open water all over the ice pack and huge melt lakes and ponds.

Melt ponds, sure. But open water? I don't really see it. The resolution on sat pics is not great, but still..

[gerontocrat]

Confirmation that NSIDC have got a problem.

[ArcticMelt2]

Confirmation that NSIDC have got a problem.

Did the satellite break down?

[gerontocrat]

Confirmation that NSIDC have got a problem.

Did the satellite break down?

That is always the worry as the satellite is so old, & there is no replacement. (A really bad story lies behind that). Hopefully, the satellite and the sensors just need maintenance. Go back a few posts for the email they sent me.

[igs]

Have to wonder how we will escape disaster now.

There is a high probability that the September minimum of 2012 will stand. In July 2011, on July 20, the ice extent was 400 thousand km2 ahead of 2007, but the 2007 record was not broken.
The current situation does not guarantee a catastrophe in September.

The less extent and thickness we have and the earlier, the greater the risk that any succession of storms that start once the "new cold" and the remaining "heat" will meet next month, will destroy almost any riminder. The amount of open water at a given moment in time plays a significant role IMO.

If this weather and melt continues till end of July even a BOE is possible with decent set of storms that will make the waves, winds und mixing attack the remaining thin ice from all sides possible.

Perhaps CAA will be key because for the CAB I things look catastrophic each day the current conditions persist towards late July.

[igs]

I do think melt will stop this pace in a couple of weeks
It cant melt this much once the high gets dislodged which I presume will happen within next 10 days.

Then the other years will probably start to catch up but with this melt JAXA is now ensured of a place in the top 3 or maybe at the top tree.

Once thickness goes widely spread below 50cm it won't matter what comes next except perhaps when but not anymore "IF"

[pearscot]

One very interesting and somewhat noteworthy feature to cite is the melting of this lake on Ellesmere Island. Please verify my findings on worldview if you would like, but the ONLY year to match the current melting of this is 2012*...

*even then, go forward a few days in 2012 and see that 2020 is virtually ice free where as 2012 had more

What does this mean? I'm not totally sure, but it can certainly be added or at least taken into account that 2020 does share some similarities with 2012, in this region at least. I also think the crack/overall state of the ice in this region indicate just how much warmth has been sustained there. 

[Frivolousz21]

THE EURO HAS A 970MB VORTEX AT HOUR 192.

[blumenkraft]

Remember the 'greyening' earlier this year, Pearscot?

https://forum.arctic-sea-ice.net/index.php/topic,176.msg261819.html#msg261819

[Frivolousz21]

THE EURO HAS A 970MB VORTEX AT HOUR 192.

Although in order for the euro to make this happen two decently strong pieces of VORTICITY phase along a mid level boundary layer.

And this helps aid the new VORTEX bomb out

[Greenbelt]

So ECMWF Days 1-3 strengthens the GAAC from 1029mb to 1034. Days 4-6 shifts the GAAC toward the ESS allowing very warm southerly winds off Siberia to fetch far into the Central Arctic. Then Days 7-8 rapidly develops a sub 980mb low.  That model does not like ice.