Support the Arctic Sea Ice Forum and Blog

Author Topic: The 2020 melting season  (Read 1137461 times)

pearscot

  • Frazil ice
  • Posts: 385
    • View Profile
  • Liked: 190
  • Likes Given: 65
Re: The 2020 melting season
« Reply #700 on: May 10, 2020, 09:24:32 PM »
Has transport out of the Fram been higher than normal this year or lately? That's one part of the arctic I know little about.
pls!

Phoenix

  • Guest
Re: The 2020 melting season
« Reply #701 on: May 10, 2020, 09:52:03 PM »
Has transport out of the Fram been higher than normal this year or lately? That's one part of the arctic I know little about.

It has had both fast and slow phases. Wipneus has an excellent chart for that in the PIOMAS thread.

Frivolousz21

  • Nilas ice
  • Posts: 1915
  • Live in Belleville, IL..15 miles SE of St. Louis.
    • View Profile
  • Liked: 598
  • Likes Given: 7
Re: The 2020 melting season
« Reply #702 on: May 11, 2020, 12:23:11 AM »
Been busy.

Just saw the 12Z euro.

Holy mother f***ing s**t!!!

« Last Edit: May 11, 2020, 11:11:25 AM by oren »
I got a nickname for all my guns
a Desert Eagle that I call Big Pun
a two shot that I call Tupac
and a dirty pistol that love to crew hop
my TEC 9 Imma call T-Pain
my 3-8 snub Imma call Lil Wayne
machine gun named Missy so loud
it go e-e-e-e-ow e-e-e-e-e-e-blaow

Glen Koehler

  • Grease ice
  • Posts: 931
    • View Profile
  • Liked: 738
  • Likes Given: 1413
Re: The 2020 melting season
« Reply #703 on: May 11, 2020, 01:14:23 AM »
    Climate Reanalyzer GFS
https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.t2anom
and Earth Nullschool https://earth.nullschool.net/#2020/05/14/0600Z/wind/surface/level/orthographic=-59.54,45.21,332
show
   a) Strong positive temperature anomalies for next week over most of the Arctic Ocean (ArcOc)

   b) Surface temperatures warm enough to advance ice melt over large areas of ArcOc

   c) A persistent high-pressure system over the ArcOc for the next week or more, resulting in what I interpret to be large areas of clear sky -- during mid-May with solar shortwave radiation within 6 weeks of annual max, thus beginning of the 3-month period of highest solar gain.  (The color scheme is subtle but if I remember correctly, the CR creator told me the light blue indicates clear skies over ice.)

   d) A persistent low-pressure system east of NE Greenland that creates a strong windfield on May 10-13 for increased Fram export.

     Any one of these four would be noteworthy on their own.  The combination seems remarkable.   
“What is at stake.... Everything, I would say." ~ Julienne Stroeve

Glen Koehler

  • Grease ice
  • Posts: 931
    • View Profile
  • Liked: 738
  • Likes Given: 1413
Re: The 2020 melting season
« Reply #704 on: May 11, 2020, 01:29:27 AM »
... and add this to the pile
    Check out the forecast change in snow depth at https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.snowd-mslp
    I suppose that happens every May and I don't have the experience to say how the current forecast compares to the normal rate of snow depth decline, but it looks like a big drop over a 10 day period.

    It will be interesting to how this multifaceted weather assault will affect the Extent and Area stats over the coming week.  It also looks like conditions that promote melt pond development which Neven and others have pointed to as a factor that influences that the longer-term melt season.  And it makes me wonder whether the MOSAIC experiments that were left in place will still be there when the Polarstern gets back.

    PS The cumulative precip forecast supports the "clear sky under the high-pressure system" interpretation mentioned previously.
https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.aprcp
« Last Edit: May 11, 2020, 02:12:39 AM by Glen Koehler »
“What is at stake.... Everything, I would say." ~ Julienne Stroeve

Phoenix

  • Guest
Re: The 2020 melting season
« Reply #705 on: May 11, 2020, 02:43:32 AM »
    Climate Reanalyzer GFS

   a) Strong positive temperature anomalies for next week over most of the Arctic Ocean (ArcOc)

   b) Surface temperatures warm enough to advance ice melt over large areas of ArcOc

   c) A persistent high-pressure system over the ArcOc for the next week or more, resulting in what I interpret to be large areas of clear sky -- during mid-May with solar shortwave radiation within 6 weeks of annual max, thus beginning of the 3-month period of highest solar gain.  (The color scheme is subtle but if I remember correctly, the CR creator told me the light blue indicates clear skies over ice.)

   d) A persistent low-pressure system east of NE Greenland that creates a strong windfield on May 10-13 for increased Fram export.

     Any one of these four would be noteworthy on their own.  The combination seems remarkable.   

Certainly some impressive weather conditions. But I'll share the more conservative view.

The euro forecast for >= 0C temps in the Arctic is not as ambitious as the GFS you're sharing. We'll get the facts in a few days.

The extra solar radiation due to clear skies is probably not a game changer with the Arctic Basin still covered in ice and having a high albedo.

The winds set to push ice through the Fram are truly impressive. Forecast peak  is 55 kts. We'll be in turbo mode for some days. Looks like a high intensity, short-medium duration event.

The areas where ice is most likely to remain at the minimum are the deep CAB and the regions of the Beaufort and CAA which are adjacent to the CAB. Those areas are looking better protected than at a similar point in 2019 and shouldn't be substantially impacted by this week's conditions.

So far 2020 is reminding me of the parable about the tortoise and the hare. Some definite sprinting at the moment, but also some extended periods of napping.

oren

  • Moderator
  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: The 2020 melting season
« Reply #706 on: May 11, 2020, 05:51:07 AM »
Snow cover in Alaska has been decimated in the past few days.
https://forum.arctic-sea-ice.net/index.php/topic,2876.msg263656.html#msg263656

Pavel

  • Frazil ice
  • Posts: 263
    • View Profile
  • Liked: 48
  • Likes Given: 9
Re: The 2020 melting season
« Reply #707 on: May 11, 2020, 07:47:29 AM »
The Chukchi sea ice is starting to turning blue, the image of yesterday

Phoenix

  • Guest
Re: The 2020 melting season
« Reply #708 on: May 11, 2020, 07:49:17 AM »
   

It just maybe that over the next week or more we will see Arctic sea ice (and snow cover) under attack on all  fronts at various times - i.e. a major warming event


How will we know if said warming event materializes and the extent of it? Something like DMI 80 ?

bbr2315

  • Grease ice
  • Posts: 580
    • View Profile
  • Liked: 73
  • Likes Given: 77
Re: The 2020 melting season
« Reply #709 on: May 11, 2020, 07:52:39 AM »
This impending dipole may not impact extent and area outright but it could make quite a dent on volume / export....


Phoenix

  • Guest
Re: The 2020 melting season
« Reply #710 on: May 11, 2020, 08:35:24 AM »
windy.com has a nice feature that allows a user to toggle back and forth between GFS and ECMWF forecast models.

They feature is revealing a substantial difference between the models as it pertains to current warmth penetration into higher latitudes. GFS is showing >0 all the way to the north pole while ECMWF is not showing anything remotely close to that.

Please remember to incorporate an appreciation for a level of uncertainty in the forecasts being presented, particularly when there is strong model disagreement. Those Climate Reanalyzer images are based upon the projections of the GFS model. They are not facts.


grixm

  • Grease ice
  • Posts: 699
    • View Profile
  • Liked: 374
  • Likes Given: 131
Re: The 2020 melting season
« Reply #711 on: May 11, 2020, 11:04:32 AM »
windy.com has a nice feature that allows a user to toggle back and forth between GFS and ECMWF forecast models.

They feature is revealing a substantial difference between the models as it pertains to current warmth penetration into higher latitudes. GFS is showing >0 all the way to the north pole while ECMWF is not showing anything remotely close to that.

Please remember to incorporate an appreciation for a level of uncertainty in the forecasts being presented, particularly when there is strong model disagreement. Those Climate Reanalyzer images are based upon the projections of the GFS model. They are not facts.

I suspect this is mostly due to differences in how the models simulate the air very close to the ground, where temperatures will be mostly capped to max near 0 degrees due to interactions with the ice. The 850 hPa temperature anomaly is a pretty good indication of where the ground temperature anomaly wants to be had it not been for the ice, and if you look at that, the GFS and Euro are very similar in intensity. In fact at some frames the Euro looks even warmer over the pole than the GFS does. Below is the GFS and Euro respectively at +48h.




Phoenix

  • Guest
Re: The 2020 melting season
« Reply #712 on: May 11, 2020, 11:33:36 AM »

The 850 hPa temperature anomaly is a pretty good indication of where the ground temperature anomaly wants to be had it not been for the ice, and if you look at that, the GFS and Euro are very similar in intensity. In fact at some frames the Euro looks even warmer over the pole than the GFS does. Below is the GFS and Euro respectively at +48h.

The 850 hPa temperature is somewhere away from the ice. I'm not sure of the altitude, maybe someone with more knowledge than me can provide that.

But it is the temperature adjacent to the ice that is going to impact the ice, not the temperature 1,000 feet above sea level. For the benefit of the lurkers who are reading the thread, I think it's useful to kick the tires and questions some assumptions about the magnitude of the current events.

The heat coming into the Chukchi and ESS and the high winds pushing ice through Fram is quite significant and easily understandable and acceptable. No problem.

Maintaining heat over ice for a very long distance over ice and delivering it to the surface of much of the CAB where it can impact the ice in May is a completely differently animal. Skepticism of this is healthy from a scientific perspective.

 

gerontocrat

  • Multi-year ice
  • Posts: 20376
    • View Profile
  • Liked: 5289
  • Likes Given: 69
Re: The 2020 melting season
« Reply #713 on: May 11, 2020, 11:33:52 AM »
   

It just maybe that over the next week or more we will see Arctic sea ice (and snow cover) under attack on all  fronts at various times - i.e. a major warming event


How will we know if said warming event materializes and the extent of it? Something like DMI 80 ?
Being mid-May, a significant & sustained warming event should show up in extent, area & volume losses greater than average. and in accelerated snow cover extent & snow water equivalent reductions.

Temps North of 80 from DMI is just one of those measures, but this event looks like causing happenings at various times at all points North of 50 as weather systems traverse the Arctic & beyond..

It is 1030 am. & still no JAXA data - patience is a virtue?
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

BornFromTheVoid

  • Nilas ice
  • Posts: 1339
    • View Profile
  • Liked: 679
  • Likes Given: 299
Re: The 2020 melting season
« Reply #714 on: May 11, 2020, 11:53:30 AM »
The 850 hPa temperature is somewhere away from the ice. I'm not sure of the altitude, maybe someone with more knowledge than me can provide that.

But it is the temperature adjacent to the ice that is going to impact the ice, not the temperature 1,000 feet above sea level. For the benefit of the lurkers who are reading the thread, I think it's useful to kick the tires and questions some assumptions about the magnitude of the current events.

The heat coming into the Chukchi and ESS and the high winds pushing ice through Fram is quite significant and easily understandable and acceptable. No problem.

Maintaining heat over ice for a very long distance over ice and delivering it to the surface of much of the CAB where it can impact the ice in May is a completely differently animal. Skepticism of this is healthy from a scientific perspective.

Surface air temperatures over the ice are held close to a 0C maximum due to the latent heat of fusion of ice. This is quite apparent each year on the DMI 80N temperatures. For that reason, using something like the 850hPa temperature (or the less common, 925hPa value) is useful for assessing the relative heat mass over the ice. It's far from perfect, and temperature inversions, fog and such will add more complications, but much of the time in summer, 850hPa temperatures are more useful than surface temperatures.
« Last Edit: May 11, 2020, 01:08:57 PM by BornFromTheVoid »
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

Aluminium

  • Nilas ice
  • Posts: 1463
    • View Profile
  • Liked: 1140
  • Likes Given: 680
Re: The 2020 melting season
« Reply #715 on: May 11, 2020, 11:58:36 AM »
High air affects ice via infrared radiation from thick layer. This power is comparable with sunlight.

be cause

  • Nilas ice
  • Posts: 2441
    • View Profile
  • Liked: 1012
  • Likes Given: 1034
Re: The 2020 melting season
« Reply #716 on: May 11, 2020, 12:06:05 PM »
... and after gfs's improvements last year they are no longer an outlier ( or out'n'out liar :) ) with regard to forecast heat in the Arctic basin .

.. and last year Neven was saying anticyclonic weather in May was no bad thing when it came to ice survival . Good to have another chance to observe .. b.c.
 
Conflict is the root of all evil , for being blind it does not see whom it attacks . Yet it always attacks the Son Of God , and the Son of God is you .

Niall Dollard

  • Nilas ice
  • Posts: 1154
    • View Profile
  • Liked: 460
  • Likes Given: 117
Re: The 2020 melting season
« Reply #717 on: May 11, 2020, 12:32:55 PM »
For temperatures at 2 metres, I have not found the GFS to be particularly accurate across the Arctic basin. These are modelled temperatures and it tends sometimes to err on the positive side. (sometimes too it can go the other way).

Real data is sparse. We do have the Polarstern reporting currently at 83.5 N 13.1 E

Its temperature at 9UTC today was -13.4 C. Using Nullschool, the GFS model is showing a temperature of -9.3 C for same time/location. 

850hPa temps are useful to help show the expected air mass moving in. But it should always be remembered that these are temps at circa 1500 metres, way above the ice.

The Arctic is well known for temperature inversions (as mentioned already by BFTV). Fog/mist and stratus can often form over the surface of the ice keeping temps there cool when the sun is shining only a short distance higher up.



I think this low pressure in the Fram Strait on Wednesday will be very significant for ice export. NE coast of Greenland is expected to be battered by north winds gusting to 120 km/hr, extending well down the Fram.   
« Last Edit: May 11, 2020, 12:40:26 PM by Niall Dollard »

bluice

  • Guest
Re: The 2020 melting season
« Reply #718 on: May 11, 2020, 12:46:29 PM »
.. and last year Neven was saying anticyclonic weather in May was no bad thing when it came to ice survival . Good to have another chance to observe .. b.c.
 
2019 season thread has plenty of discussion about that.

But if my memory serves me right, the conclusion was that sunshine per se is not necessarily that bad for ice in the early season. Albedo is high and surface temperature stays low. This time, however, we are getting a "hot high" with warm air mass that could initiate surface melt thus lowering albedo.

Phoenix

  • Guest
Re: The 2020 melting season
« Reply #719 on: May 11, 2020, 01:08:18 PM »

Surface air temperatures over the ice are held close to a 0C maximum due to the latent heat of fusion of ice. This is quite apparent each year on the DMI 80N temperatures. For that reason, using something like the 850hPa temperature (or the less common, 925hPa value) is useful for assessing the relative heat mass over the ice. It's far from perfect, and temperature inversions, fog and such will add more complications, but much of the time in summer, 850hPa temperatures are more useful that surface temperatures.

Temperatures over the ice surface are not held close to zero everywhere. They are well above zero over the ice near the coast in the ESS and Chukchi at the moment. Seems the latent heat of fusion doesn't work when the ice is near a giant heated rock (Siberia) ??

Surface temps N of 80N stay close to zero because they are far away from the big heated rocks of Siberia and NA. That's why the ice remains there at the September minimum. Transporting enough heat over long distance to the surface of the CAB ice is not a trivial matter.




grixm

  • Grease ice
  • Posts: 699
    • View Profile
  • Liked: 374
  • Likes Given: 131
Re: The 2020 melting season
« Reply #720 on: May 11, 2020, 01:23:21 PM »
Surface temps N of 80N stay close to zero because they are far away from the big heated rocks of Siberia and NA. That's why the ice remains there at the September minimum. Transporting enough heat over long distance to the surface of the CAB ice is not a trivial matter.

Transporting air from the south is not the only way the pole can warm up. High pressure areas, like the one being forecast now, causes sinking air, and air warms as it sinks. Which also increases the relevance of the 850 hPA air temperature, because that air is moving downwards toward the surface.

Phoenix

  • Guest
Re: The 2020 melting season
« Reply #721 on: May 11, 2020, 01:28:40 PM »

Real data is sparse. We do have the Polarstern reporting currently at 83.5 N 13.1 E

Its temperature at 9UTC today was -13.4 C. Using Nullschool, the GFS model is showing a temperature of -9.3 C for same time/location. 

850hPa temps are useful to help show the expected air mass moving in. But it should always be remembered that these are temps at circa 1500 metres, way above the ice.


Marvelous !! Actual surface data showing a 4C discrepancy from the GFS model (which runs hot in this instance).

I found similar discrepancies between the GFS and ECMWF (also a model) on Windy.com. You provide a single corroborating data point regarding the better accuracy of the euro model.

Thank you Niall.

Carex

  • New ice
  • Posts: 58
    • View Profile
  • Liked: 6
  • Likes Given: 30
Re: The 2020 melting season
« Reply #722 on: May 11, 2020, 01:32:55 PM »
Meanwhile, in sub-arctic melt progress, as of yesterday, the Great Lakes are now ice free, despite four consecutive mornings of fresh snow.  Black and Nipigon Bays, Lake Superior gave up the ghost to strong winds while temperatures hovered between -5 and +2.

Jim Hunt

  • First-year ice
  • Posts: 6268
  • Don't Vote NatC or PopCon, Save Lives!
    • View Profile
    • The Arctic sea ice Great White Con
  • Liked: 893
  • Likes Given: 87
Re: The 2020 melting season
« Reply #723 on: May 11, 2020, 01:36:47 PM »
Something like DMI 80 ?

Nope. That's heavily weighted towards the Pole.

What's more at this time of year < 80N is far more relevant than >80N
"The most revolutionary thing one can do always is to proclaim loudly what is happening" - Rosa Luxemburg

binntho

  • Nilas ice
  • Posts: 2193
    • View Profile
  • Liked: 878
  • Likes Given: 235
Re: The 2020 melting season
« Reply #724 on: May 11, 2020, 01:38:05 PM »
Surface temps N of 80N stay close to zero because they are far away from the big heated rocks of Siberia and NA. That's why the ice remains there at the September minimum. Transporting enough heat over long distance to the surface of the CAB ice is not a trivial matter.

Always interesting to read new theories of physics and meteorology in this forum.

I wonder why people think that the landmasses of Alaska and Sibera are more significant sources of heat in summer, than are the open ocean areas surrounding the ice. The open ocean absorbs much more solar energy than does dry land, has a much higher heat capacity, and has the ability to move the heat to the ice directly rather than going through the ethereal media of air.

Without the landmasses surrounding the Arcitic Ocean, I'd guess that the ice would disappear every summer. If there was no Antarctic Continent and just open ocean on the South Pole, it would lose all it''s ice every summer (methinks). It's the presence of the vast Antartic landmass that maintains the antarctic sea ice, and the same can be said for the Arctic Ocean, the ice survives by sheltering behind the landmass of America in particular, Siberia to a lesser extent.
because a thing is eloquently expressed it should not be taken to be as necessarily true
St. Augustine, Confessions V, 6

Niall Dollard

  • Nilas ice
  • Posts: 1154
    • View Profile
  • Liked: 460
  • Likes Given: 117
Re: The 2020 melting season
« Reply #725 on: May 11, 2020, 01:53:08 PM »
Yes Binntho. I suspect as more ice in the periphery goes each summer, it will be bottom melt that will take a signficant toll on the ice >85N.


Phoenix

  • Guest
Re: The 2020 melting season
« Reply #726 on: May 11, 2020, 02:05:35 PM »

Transporting air from the south is not the only way the pole can warm up. High pressure areas, like the one being forecast now, causes sinking air, and air warms as it sinks. Which also increases the relevance of the 850 hPA air temperature, because that air is moving downwards toward the surface.

Not saying that air transport is the ONLY way to get heat to the pole. The ocean will ultimately do the trick if we don't deal with AGW.

But air transport is a seriously important weapon in the current arsenal and distance from hot land is a critical defense mechanism for the CAB. I am a proponent of the possibility that the inner Arctic is much more resilient than most people think.

Bottom line is that there have been quite a few GFS model based charts being shared here the last
few days and a less educated reader might be misled by them. They should not be interpreted as a reliable indicator of surface heat in the CAB.

Freegrass

  • Young ice
  • Posts: 3825
  • Autodidacticism is a complicated word...
    • View Profile
  • Liked: 951
  • Likes Given: 1251
Re: The 2020 melting season
« Reply #727 on: May 11, 2020, 02:18:54 PM »
Five Day Forecast
Wind + Temp @ 1000hPa

Is the 1000hPa as useful as the 850hPa?
90% of the world is religious, but somehow "love thy neighbour" became "fuck thy neighbours", if they don't agree with your point of view.

WTF happened?

Phoenix

  • Guest
Re: The 2020 melting season
« Reply #728 on: May 11, 2020, 02:27:06 PM »

I wonder why people think that the landmasses of Alaska and Sibera are more significant sources of heat in summer, than are the open ocean areas surrounding the ice. The open ocean absorbs much more solar energy than does dry land, has a much higher heat capacity, and has the ability to move the heat to the ice directly rather than going through the ethereal media of air.


You're arguing a completely different point. Yes, the ocean has a higher heat capacity than the land. That's why the ocean retains it's heat and the land contributes heat to the atmosphere where it can slide over and melt the ice at the surface.

The issue in the ocean is completely different. There is a shit ton of heat below the Arctic that can melt it many times over.  The obstacle is a fresh water lens at the top which is less dense than warm salty water below.

Please explain the physics of the ocean overcoming the density gradient.


bluice

  • Guest
Re: The 2020 melting season
« Reply #729 on: May 11, 2020, 03:14:58 PM »
Phoenix, I don't have the knowledge to answer your questions but I think there are more appropriate threads for them than the main one

Maybe you can take a look at one of these for example:
https://forum.arctic-sea-ice.net/index.php/topic,143.0.html
https://forum.arctic-sea-ice.net/index.php/topic,2417.0.html
https://forum.arctic-sea-ice.net/index.php/topic,2709.0.html

oren

  • Moderator
  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: The 2020 melting season
« Reply #730 on: May 11, 2020, 06:05:01 PM »
Thank you bluice.
All, please remember this thread is not to be bogged down in back and forth arguments, so once something becomes a thing take it elsewhere. And please be aware that someone will always disagree, no need to get defensive or personally respond to every point. The melting season knows better than us all and often patience is the best tool in the ice enthusiast arsenal. If you're right, you'll be proven right. If you're wrong, you'll be proven wrong. And if it depends on weather and luck, best not to make big predictions. Let the thread breathe, wait for new data to come in, I promise it will be interesting.

igs

  • Guest
Re: The 2020 melting season
« Reply #731 on: May 11, 2020, 07:41:59 PM »
It is 1030 am. & still no JAXA data - patience is a virtue?



Patience has paid of:


https://ads.nipr.ac.jp/vishop/#/extent


If that's what you meant

oren

  • Moderator
  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: The 2020 melting season
« Reply #732 on: May 11, 2020, 09:41:24 PM »
The ADS website is back up, but the extent data is still only up to May 7th.

thejazzmarauder

  • New ice
  • Posts: 39
    • View Profile
  • Liked: 5
  • Likes Given: 8
Re: The 2020 melting season
« Reply #733 on: May 12, 2020, 01:26:25 AM »
.. and last year Neven was saying anticyclonic weather in May was no bad thing when it came to ice survival . Good to have another chance to observe .. b.c.
 
2019 season thread has plenty of discussion about that.

But if my memory serves me right, the conclusion was that sunshine per se is not necessarily that bad for ice in the early season. Albedo is high and surface temperature stays low. This time, however, we are getting a "hot high" with warm air mass that could initiate surface melt thus lowering albedo.
May 2016 might end up being a good analog; check out the temperature and hPa anomalies over the arctic.

Phoenix

  • Guest
Re: The 2020 melting season
« Reply #734 on: May 12, 2020, 02:51:13 AM »
First sighting of a positive SST in the Beaufort Sea. +1C temperatures in a small region off the Canadian coast, just E of Alaska.

https://www.windy.com/-Sea-temperature-sst?sst,2020-05-21-06,69.119,-137.706,6,m:fATaclQ

Phoenix

  • Guest
Re: The 2020 melting season
« Reply #735 on: May 12, 2020, 03:24:05 AM »
Fairbanks hit 82F (28C) yesterday, record for the date is 84F.

https://www.inquirer.com/weather/philadelphia-weather-record-fairbanks-alaska-polar-vortex-20200510.html

Central Alaska is the primary heat source for the melting event taking place in the Chukchi and ESS. Facilitated by the Arctic high and Bering / Siberia low which is pulling the air from AK toward Siberia.
« Last Edit: May 12, 2020, 04:32:52 AM by Phoenix »

bbr2315

  • Grease ice
  • Posts: 580
    • View Profile
  • Liked: 73
  • Likes Given: 77
Re: The 2020 melting season
« Reply #736 on: May 12, 2020, 03:26:31 AM »
I have a feeling the GFS is overdoing the rapid snow-melt in some regions, as is its typical bias (I think its initialized depth levels are generally too low). This explains the discrepancy between GFS / CMC + EURO. While we are certainly in for a dipole, and it may be unprecedented in both scope and warmth, I do think the GFS may be overdone. The CMC has an excellent handle on Canadian snowcover, from my experience, while EURO is probably best hemispherically.

Frivolousz21

  • Nilas ice
  • Posts: 1915
  • Live in Belleville, IL..15 miles SE of St. Louis.
    • View Profile
  • Liked: 598
  • Likes Given: 7
Re: The 2020 melting season
« Reply #737 on: May 12, 2020, 05:11:54 AM »
I don't mean to be rude but who cares about modeled 2M y
Temps.

Let's take a look at only thing that really matters.

Surface albedo. So for May 11th everything looks as you would expect.

The surface albedo is steadily dropping quickly over the ESS and Chuckchi and that line is marching North.

The thing that stands out to me is how sunny things are.

Man it won't take long under sunny conditions with the current solar insolation levels equal to July 30th for surface albedo to plummet.
« Last Edit: May 12, 2020, 05:39:28 AM by Frivolousz21 »
I got a nickname for all my guns
a Desert Eagle that I call Big Pun
a two shot that I call Tupac
and a dirty pistol that love to crew hop
my TEC 9 Imma call T-Pain
my 3-8 snub Imma call Lil Wayne
machine gun named Missy so loud
it go e-e-e-e-ow e-e-e-e-e-e-blaow

Frivolousz21

  • Nilas ice
  • Posts: 1915
  • Live in Belleville, IL..15 miles SE of St. Louis.
    • View Profile
  • Liked: 598
  • Likes Given: 7
Re: The 2020 melting season
« Reply #738 on: May 12, 2020, 05:27:28 AM »
Just took a look at the 12Z euro.

The huge ridging slowly sliding across the arctic the next 10 days is stunning.


It's going to be 24 hours a day sun.

Granted that's not the same sun as in June.

But there is no way with that kind of wall to wall solar beating the surface albedo won't decay over a large portion of the Arctic basin.

In the biggest melt years like 07, 10, 11, 12, 15, and 16 we didn't see arctic basin albedo really drop until the second week of June or later.

In 2012 IIRC it really plummeted at the end of the first week of June and that was still really early.

Maybe it's not physically plausible yet with the solar elevation angle and what not.

But insolation today between 70-90N is already above 417W/m2 by the 22nd that's about 475w/m2.



This could be the breakthrough. 



Look this is simple.... If by the 20th a large portion of the Arctic basin has seen surface albedo drop from the largely pristine 0.85 dry snow to 0.60 wet snow and 0.5-0.6 bare/wet ice with 10 days left in May.

Like HOLY SHIT!
I got a nickname for all my guns
a Desert Eagle that I call Big Pun
a two shot that I call Tupac
and a dirty pistol that love to crew hop
my TEC 9 Imma call T-Pain
my 3-8 snub Imma call Lil Wayne
machine gun named Missy so loud
it go e-e-e-e-ow e-e-e-e-e-e-blaow

Frivolousz21

  • Nilas ice
  • Posts: 1915
  • Live in Belleville, IL..15 miles SE of St. Louis.
    • View Profile
  • Liked: 598
  • Likes Given: 7
Re: The 2020 melting season
« Reply #739 on: May 12, 2020, 05:38:53 AM »
For May 12th at 75N

You get about 10 hours with the sun above 20° altitude.

The solar altitude peak is 34°

You get about 6 hours at 30°+.

At 81N you got about 10 hours above 20° and 6 hours above 25° peaking at 30°

Obviously everyday that passes the solar altitude increases quickly

I got a nickname for all my guns
a Desert Eagle that I call Big Pun
a two shot that I call Tupac
and a dirty pistol that love to crew hop
my TEC 9 Imma call T-Pain
my 3-8 snub Imma call Lil Wayne
machine gun named Missy so loud
it go e-e-e-e-ow e-e-e-e-e-e-blaow

oren

  • Moderator
  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: The 2020 melting season
« Reply #740 on: May 12, 2020, 05:39:30 AM »
Temps in Pevek (ESS) have been running at record or near-record high for the date in the last 4 days.

pearscot

  • Frazil ice
  • Posts: 385
    • View Profile
  • Liked: 190
  • Likes Given: 65
Re: The 2020 melting season
« Reply #741 on: May 12, 2020, 05:58:43 AM »
The impact of the sun will be very interesting to follow. I was also extremely surprised to see how warm it was in central Alaska. I've been reading the detailed forecast discussion for Barrow to get a better handle on what to expect in that small corner of the arctic. In sum, the aforementioned snow melt is noted with several rivers at elevated flow rates.

Beyond that, I've been surprised with basic visual comparisons of sea ice coverage throughout the entire arctic. The most notable difference, to my eye, is the extent this year into the Bering Sea/north of Alaska. There are also some areas around Greenland which certainly have more robust sea ice in far better condition compared to the same date last year. I'm not sure how much of a difference all of that will make going forward.

One still can't deny the data and realize that while some areas have more ice this year, others have less. The most interesting component of the distribution of ice will be to see how quickly it melts out and if it looks like subsurface melting will be intensified by both Atlantification (and I'm not even sure if Pacification is a term, but that too). So much to focus on right now, but I have a much better handle on the state of the ice now than I did in January.
pls!

charles_oil

  • Frazil ice
  • Posts: 337
    • View Profile
  • Liked: 38
  • Likes Given: 74
Re: The 2020 melting season
« Reply #742 on: May 12, 2020, 06:00:27 AM »

Oren - any chance of some titles for the Pevek graph ?  Not sure what we are seeing …. different sensors / years / averages ?  Tks

Frivolousz21

  • Nilas ice
  • Posts: 1915
  • Live in Belleville, IL..15 miles SE of St. Louis.
    • View Profile
  • Liked: 598
  • Likes Given: 7
Re: The 2020 melting season
« Reply #743 on: May 12, 2020, 06:30:39 AM »
The Kara.  Atleast half of it gets a big time blast of warmth over the next 72 hours.


That will decimate surface albedo there.

The 00z gfs through 192 hours is absurd.

The laptev bite will dramatically open up.

I got a nickname for all my guns
a Desert Eagle that I call Big Pun
a two shot that I call Tupac
and a dirty pistol that love to crew hop
my TEC 9 Imma call T-Pain
my 3-8 snub Imma call Lil Wayne
machine gun named Missy so loud
it go e-e-e-e-ow e-e-e-e-e-e-blaow

aperson

  • Frazil ice
  • Posts: 228
    • View Profile
  • Liked: 100
  • Likes Given: 131
Re: The 2020 melting season
« Reply #744 on: May 12, 2020, 07:11:05 AM »
I agree with friv, and think one additional ingredient here is the amount of ice that will be sent down the death zone past Svalbard and out the Fram strait. We're looking at 4+ days of strong surface winds exporting ice. Just look at how packed the isobars are on this output and how well they are positioned to export ice.
computer janitor by trade

Frivolousz21

  • Nilas ice
  • Posts: 1915
  • Live in Belleville, IL..15 miles SE of St. Louis.
    • View Profile
  • Liked: 598
  • Likes Given: 7
Re: The 2020 melting season
« Reply #745 on: May 12, 2020, 07:58:41 AM »
I agree with friv, and think one additional ingredient here is the amount of ice that will be sent down the death zone past Svalbard and out the Fram strait. We're looking at 4+ days of strong surface winds exporting ice. Just look at how packed the isobars are on this output and how well they are positioned to export ice.

That ain't no joke that is crazy you're going to see open water come in the kara or the laptev because of all this
I got a nickname for all my guns
a Desert Eagle that I call Big Pun
a two shot that I call Tupac
and a dirty pistol that love to crew hop
my TEC 9 Imma call T-Pain
my 3-8 snub Imma call Lil Wayne
machine gun named Missy so loud
it go e-e-e-e-ow e-e-e-e-e-e-blaow

Frivolousz21

  • Nilas ice
  • Posts: 1915
  • Live in Belleville, IL..15 miles SE of St. Louis.
    • View Profile
  • Liked: 598
  • Likes Given: 7
Re: The 2020 melting season
« Reply #746 on: May 12, 2020, 08:04:04 AM »
I agree with friv, and think one additional ingredient here is the amount of ice that will be sent down the death zone past Svalbard and out the Fram strait. We're looking at 4+ days of strong surface winds exporting ice. Just look at how packed the isobars are on this output and how well they are positioned to export ice.

That ain't no joke that is crazy you're going to see open water come in the kara or the laptev because of all this

The Kara gets blasted with straight heat.

However far that warn sector reaches into the Arctic ice albedo is toast.

I got a nickname for all my guns
a Desert Eagle that I call Big Pun
a two shot that I call Tupac
and a dirty pistol that love to crew hop
my TEC 9 Imma call T-Pain
my 3-8 snub Imma call Lil Wayne
machine gun named Missy so loud
it go e-e-e-e-ow e-e-e-e-e-e-blaow

Lord M Vader

  • Nilas ice
  • Posts: 1406
    • View Profile
  • Liked: 60
  • Likes Given: 39
Re: The 2020 melting season
« Reply #747 on: May 12, 2020, 08:38:43 AM »
Kara should implode soon.

Another area that should see damage is the area just north of Svalbard. Hammered by a 961 hpa bomb cyclone in tandem with a 1044 hpa high pressure over the CAB will push some thick ice piled up there out in the Atlantic killer zone. However, this won't last long but should nevertheless have an impact on the ice.

Later in the forecast period, Laptev will take a big hit.

thejazzmarauder

  • New ice
  • Posts: 39
    • View Profile
  • Liked: 5
  • Likes Given: 8
Re: The 2020 melting season
« Reply #748 on: May 12, 2020, 09:08:06 AM »
A year ago to the day, there was forecasted high pressure that resulted in some interesting analysis. Take a look at the 2019 melting season thread from 5/12/19 through about 5/21/19: https://forum.arctic-sea-ice.net/index.php/topic,2591.800.html

Frivolousz21

  • Nilas ice
  • Posts: 1915
  • Live in Belleville, IL..15 miles SE of St. Louis.
    • View Profile
  • Liked: 598
  • Likes Given: 7
Re: The 2020 melting season
« Reply #749 on: May 12, 2020, 09:46:07 AM »
A year ago to the day, there was forecasted high pressure that resulted in some interesting analysis. Take a look at the 2019 melting season thread from 5/12/19 through about 5/21/19: https://forum.arctic-sea-ice.net/index.php/topic,2591.800.html

We had a short lived dipole that helped open water and keep 2019 second lowest extent.

This is different and unprecedented in the modern era.  I'm sure you might find this somewhere in the historical record from Noaa back 200 years.

But this is a potential near basin wide albedo buster.

Look this this ridge.  It's amazing.

And the partial sat image shows the carved out sunny circle.

Similar to June 2007.

We can see the ice albedo is already compromised over the ESS and laptev.

The lighter color in the Arctic basin the last 2 days has started to darken.  Once it turns red the cooling properties of a surface reflecting .85 insolation is gone and a drop to .5-.6 is a HUGE difference


I got a nickname for all my guns
a Desert Eagle that I call Big Pun
a two shot that I call Tupac
and a dirty pistol that love to crew hop
my TEC 9 Imma call T-Pain
my 3-8 snub Imma call Lil Wayne
machine gun named Missy so loud
it go e-e-e-e-ow e-e-e-e-e-e-blaow