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Messages - grixm

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1
Arctic sea ice / Re: The 2020 melting season
« on: August 04, 2020, 10:22:06 AM »
July 30 - August 3.


Looks like the entire pack is slowly being pulled apart down the middle. You can see it on the drift chart too.

2
Arctic sea ice / Re: The 2020 melting season
« on: July 28, 2020, 02:17:58 PM »
Another quite large daily drop in area. We are now below 4 million km^2.

3
Arctic sea ice / Re: The 2020 melting season
« on: July 25, 2020, 01:50:47 PM »
How is this ice here being so robust? It's very warm in the water and air, there's little other ice around to buffer the heat, and last PIOMAS update the 15th said that the ice was quite thin at that time. Yet it is still there in significant amounts, it almost doesn't look like it has melted much at all in the past week or two.

4
Arctic sea ice / Re: The 2020 melting season
« on: July 23, 2020, 08:06:29 AM »
The ice is compact, I don't understand how that's a controversial statement at all. Like it has been said before, compactness is just area divided by extent. And that figure is very high, as is to be expected after the central basins have experienced compacting winds for weeks on end.

5
Has anyone combined the PIMOAS thickness data with AMSR2 area to create a better volume measurement then?

6
Arctic sea ice / Re: The 2020 melting season
« on: July 19, 2020, 07:43:10 AM »
The animation below is from the laptev and near ESS.

The last 4 days.

We can see major melt out in PLACE...

Now that is pretty interesting. With the constant compacting winds one would expect such gaps to be quickly filled by the ice around it, rather than expand because they melt even faster than new ice can fill them.

7
The forum / Re: Forum Decorum
« on: July 18, 2020, 10:30:26 PM »
I must ask why in the world blumenkraft's comment accusing GSY of making a racial slur was left in the melting thread. It is 1) completely off-topic and derailing, and 2) an unfounded and outrageous attack on his character, at least it looks that way from the outside. It deserved to be deleted as much as any of GSY's posts as it was the root cause of the entire drama. Fellow moderators cannot be given special treatment.

8
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: July 18, 2020, 06:02:08 PM »
I don't think NSIDC area will ever reach zero unless they apply a mask in the Gulf of Ob and the Yenisey Gulf. The NSIDC algorithm thinks ice is present there year-round.

Of course it will if things continue as they are, just maybe not in your lifetime.

He means that it is literally impossible for the NSIDC area to reach zero because the model erroneously but consistently reports ice in areas where there is none, such as the gulf of Ob.

9
Arctic sea ice / Re: The 2020 melting season
« on: July 15, 2020, 08:03:23 PM »
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..

10
Arctic sea ice / Re: The 2020 melting season
« on: July 13, 2020, 08:19:21 AM »
July 8-12.

2019.

It is impressive how a protruding Laptev "bite" is not stretching towards the 80N line like most years, but instead the whole width of the Laptev sea reached 80N at the same time

11
Arctic sea ice / Re: Northern Sea Route thread
« on: July 12, 2020, 10:53:24 PM »
This kind of seeking "official" agains visible, physical and mathematical  facts is part of what
kept us to react to AGW in time, even though my teachers told me it will eventually happen about 60 years ago in school.

The route is navigable, it think we're talking about the development and behaviour of the arctic ice in the first place and not about some russion civil cervants feeling fit to announce something today or tomorrow because it's i.e. Sunday.

While I understand where you are coming from, a sea route opening is not a scientific event, it is shipping-related event. The route is open when the ships can start sailing it. And this does not equate there being no ice in the route, it equates the ships having confidence that there is no ice in the route. Because without this confidence, the ships will not attempt to sail the route, even if it would have worked if they gambled and tried anyway. And such confidence requires confirmation from a better source than just hobbyists peeking at low-resolution cloudy satellite images.

12
Arctic sea ice / Re: The 2020 melting season
« on: July 11, 2020, 10:52:01 PM »
Fun fact: If my calculations are correct then the current rotation of the central basins sea ice due to the anticyclone carries about 2E13 joules of kinetic energy. This must be eventually converted to heat for the rotation to stop, which is enough to melt 60 000 cubic meters of ice. This might sound significant at first but actually it is just the equivalent of around 10 nanometers of ice thickness across the arctic.

13
Arctic sea ice / Re: The 2020 melting season
« on: July 09, 2020, 09:45:37 PM »
This animation seems to show a lot of transport south through the Fram being driven by the GAA.  How does this compare with satellite era averages for the summer months?

Wipneus's regular updates in the PIOMAS model thread includes a graph of fram export volume with the seasonal average: https://forum.arctic-sea-ice.net/index.php/topic,119.msg271734.html#msg271734

14
Arctic sea ice / Re: The 2020 melting season
« on: July 09, 2020, 02:10:35 PM »
While extent continues to drop, area has actually stalled for the last 4 days. More draining melt ponds?


15
Arctic sea ice / Re: The 2020 melting season
« on: July 04, 2020, 10:21:54 PM »
To be completely fair, the stirring should happen in the other direction to promote dispersion,. mechanical breakup of floes and bottom melt... One of the positive aspects of this setup is that it keeps ice compact...
Anyway, the 12z EC is slightly worse in strength and persistence of the 2020 GAH (Great Arctic High)

In my inexperience, I am puzzled by what you write, gandul.  Would there not be dispersion as well as compaction with this clockwise rotation?  It looks like this 'stirring' should result in a lot of of Fram export, starting some possible Nares export, and ice also being spread out into all the open water in the now-warming Laptev Sea and into what is a rapidly melting Chukchi.  I understand that ice might tend to be jammed together along the Canadian side, but wouldn't it also be dispersed further in other areas, where it may well then rapidly melt?  I may be missing something and would be glad to learn.

Ice is generally pushed inwards under anticyclones (clockwise rotation). This is because the wind pushing on the ice actually makes the ice move at an angle further to the right than would be expected, because of the Coriolis effect. Here is a basic diagram on how the ice would move with this setup (probably a bit exaggerated). Of course this is approximate, and also doesn't account for ocean currents, collisions with other ice or land, etc.


16
Arctic sea ice / Re: The 2020 melting season
« on: July 03, 2020, 05:39:22 PM »
Area anomaly. Useful map that for some reason isn't posted very often.

17
Arctic sea ice / Re: The 2020 melting season
« on: July 02, 2020, 06:12:43 PM »
Maybe someone can answer this for me. With 2020 just about going lowest on record today, how come the NSIDC extent line has 2020 8th lowest? According to the NSIDC, 2020 is above 2010, 11, 12, 14, 16, 17 and 19 and whilst for some years the gap is small, in other years its quite a large difference especially with 2010 whilst JAXA has it effectively level, NSIDC has 2010 way ahead.

I know the NSIDC uses a 5 day average and the resolution is lower but we have never been above 2012 on JAXA yet the NSIDC has 2020 above 2012 for a good while now. I don't think I have seen JAXA and NSIDC looking so different before and are usually on the same page.

Well, one reason could be that NSIDC is not as good as JAXA to measure along the coast and gulfs. This is especially relevant now because many river outlets in Russia melted out record early, but the NSIDC extent does not pick up on this. You can see below one such example circled in red. This area is actually completely devoid of ice. But in some other years, like 2017, 2014, 2019, and 2011 out of the years you mentioned, there were still ice here. Yet NSIDC would report the same extent as now, unlike JAXA.

18
Arctic sea ice / Re: The 2020 melting season
« on: July 02, 2020, 02:56:42 PM »
Big daily drop in area today. Won't immediately show up on gerontocrat's 5-day average charts, but if this keeps up the area will be record daily low very soon.

19
Arctic sea ice / Re: The 2020 melting season
« on: June 18, 2020, 09:34:45 AM »
Not to mention that wind drastically increases the thermal conductivity between the ice and air. Just like how a fan cools you down, but with the heat traveling in the opposite direction as long as the air is warmer than the ice. And it is: Even in the middle of the storm most of the surface air is forecast to be above 0C. The wind also makes the ice move faster through the sea, which has the same effect of increasing the thermal conductivity between the water and ice.

So storms melt the ice, even if they block out the sun. But does it melt it faster or slower than a sunny day without wind? I don't know.

20
Arctic sea ice / Re: The 2020 melting season
« on: June 09, 2020, 10:19:54 AM »
A bit of fast ice breakup today, in both the ESS and Laptev sea

21
Science / Re: 2020 Mauna Loa CO2 levels
« on: June 03, 2020, 12:02:21 PM »
We got a new daily record of 418.32 ppm for June 1st

22
Policy and solutions / Re: Bikes, bikes, bikes and more...bikes
« on: May 28, 2020, 06:01:20 PM »
Uber sends thousands of electric bikes to the scrapheap
Quote
Uber is scrapping thousands of electric bikes and scooters worth millions of dollars after selling its Jump unit to mobility start-up Lime earlier this month.

The firm said it decided to “recycle” the older models that Lime didn’t want after concluding that it would be too complicated to give them away due to the maintenance and technical support that they need.

Footage of the distinctive red Jump e-bikes being destroyed at a North Carolina recycling center was shared on social media on Wednesday by user Cris Moffitt, angering bike enthusiasts around the world. ...
https://www.cnbc.com/2020/05/28/uber-bikes-scrapped.html

That is infuriating. It should be illegal.

23
Arctic sea ice / Re: River ice and Discharge
« on: May 27, 2020, 12:23:57 PM »
The ice in the Gulf of Ob seems to have shattered, meaning that essentially the Ob river is free flowing all the way to the arctic ocean.

24
Arctic sea ice / Re: The 2020 melting season
« 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.

25
Arctic sea ice / Re: The 2020 melting season
« 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.




26
Arctic sea ice / Re: Arctic Image of the Day
« on: May 08, 2020, 09:35:31 PM »
This is sea ice near Utqiaġvik, Alaska, in March, after a storm caused it to pile up. This was written about in NSIDC's newest summary: https://nsidc.org/arcticseaicenews/2020/05/storm-damage/

27
Arctic sea ice / Re: The 2020 melting season
« on: May 07, 2020, 09:48:05 PM »
12z Euro

28
Arctic sea ice / Re: DMI Volume
« on: May 07, 2020, 03:06:16 PM »
Cryosat agrees more with DMI at this time in that it shows that the volume is near or at an all time low, unlike PIOMAS. http://greatwhitecon.info/wp-content/uploads/2020/03/NRT-Vol-2020-04-15B.png

Whether DMI hits the top or bottom at the correct time is less interesting than the model's difference between years. If DMI shows that volume bottom one year was lower than another year, that is valuable information regardless of whether that bottom was in August or September. Because even if it is biased, it is biased in the same way, canceling the bias out.

Therefore, it is important information that DMI shows that the current volume is lower than any other year at this time. It is not infallible, no single model is, but it is a piece of the puzzle that should not be ignored. And doubly so since, as I said, Cryosat also says that the volume is near an all-time low.

29
Arctic sea ice / Re: The 2020 melting season
« on: May 06, 2020, 10:09:24 PM »
It looks like last week has been good for the ice. Volume has increased again.

DMI volume is essentially useless for this sort of purpose. See the DMI thread for details of why it shouldn't be used in this way.

I've read that thread but my takeaway is not that it's "useless" for this. If it shows the volume going down or up, there are good reasons for that. The input data for the model isn't just random noise, it's actual weather, meaning that if conditions for the ice is bad, it will show the volume going down, and if conditions are good, it will show the volume going up. The absolute historical values may not be as accurate as f.ex. PIOMAS due to different design goals, but it's still a working volume model and the trend should not be neglected.

30
It seems no one has posted it yet, but official breakup happened May 3rd, 17:03!

Tor Bejnar, Ranman99 and Sebastian Jones guessed the date correctly. Ranman99 was closest with the time 13:45.

31
Antarctica / Re: PIG has calved
« on: May 03, 2020, 12:12:25 PM »
Calving of sR1


32
Arctic sea ice / Re: River ice
« on: May 02, 2020, 10:16:43 AM »
Yenisei river melt is really ramping up. At this pace it will be free of ice all the way to the arctic ocean in less than two weeks. Gif is the last four days.


33
Arctic sea ice / Re: The 2020 melting season
« on: April 30, 2020, 09:39:28 PM »
Hmmm... 🤔


34
Another calving between April 27th and now




35
Arctic sea ice / Re: The 2020 melting season
« on: April 27, 2020, 07:39:25 PM »
According to Nico Sun's area calculations, we are back in spot #1 today.


36
Arctic sea ice / Re: The 2020 melting season
« on: April 24, 2020, 03:09:40 PM »
It looks like the DMI volume may have passed the season maximum.


37
Antarctica / Re: PIG has calved
« on: April 20, 2020, 09:55:30 AM »
The day has finally come.

F


38
Arctic sea ice / Re: River ice
« on: April 15, 2020, 05:41:46 PM »
Meanwhile I've been following the Yenisei river on worldview, and the melt is well underway. Here is a timelapse of the last two weeks.

39
Consequences / Re: Global Surface Air Temperatures
« on: April 14, 2020, 12:53:50 PM »
March 2020 surface air temperature anomaly seems to have been 1.18C.  Only behind 2016.

https://data.giss.nasa.gov/gistemp/maps/index_v4.html

40
Arctic sea ice / Re: The 2020 melting season
« on: April 11, 2020, 01:26:38 PM »
I thought this was kind of cool. The low in the Barents sea currently has four mesovortices, creating a kind of fidget-spinner pattern:


41
The forum / Re: Who would like to take over the ASIF?
« on: April 09, 2020, 10:30:50 PM »
Quote
Define  "offensive," "defamation," "harassment," "obscene," "racist" and "discriminatory" ?

Really, as they are perceived in a common sense. Don't insult people, don't hate on minorities, don't discriminate.

I have already posted an example of you defining racism in a way I completely disagree with. He didn't hate on minorities and yet you practically called him a nazi and said you wish he weren't allowed to post here. Can you comment on that? Will that be the definition you would use while moderating?

I have seen a blog destroyed by overzealous moderation.

So have I. Well, a subreddit, not a blog, but it really sucks and I pray this will not happen here.

42
Lots of action in the past few days, clearing of fast melange, and calvings. Click to play.

43
The forum / Re: Who would like to take over the ASIF?
« on: April 09, 2020, 04:51:14 PM »
And i would like to be allowed to fight (snip) racism (of which there is too much on the forum IMHO).

I think your definition of racism is pretty skewed. Your heart is in the right place but you are hypersensitive about it. I remember the drama in this thread where you ended up calling Archimid a "nazi handmaiden" for merely pointing out the fact that there are certain medical differences between genetic populations, such as sickle cell prevalence: https://forum.arctic-sea-ice.net/index.php/topic,2996.msg249684.html#msg249684

If these are the kinds of posts that you would label as racism and remove, then I am against you being admin, if I am being honest.

44
Arctic sea ice / Re: The 2020 melting season
« on: April 08, 2020, 03:50:55 PM »
We're off to a strong start in terms of albedo warming potential.

45
Greenland and Arctic Circle / Re: Greenland 2020 Melting Season
« on: April 07, 2020, 07:03:46 PM »
NSIDC has started updating their melt extent graph for the season. https://nsidc.org/greenland-today/greenland-surface-melt-extent-interactive-chart/

Aside from a tiny bit on April 1st, no registered melt yet.

Next week there may be some days of positive temperatures along the southwestern coast.

46
Arctic sea ice / Re: The 2020 melting season
« on: April 06, 2020, 03:48:50 PM »
The difference just one week makes in the Beaufort sea. Click to play

47
Antarctica / Re: PIG has calved
« on: April 05, 2020, 10:49:24 AM »
Some stuff has happened since the forum went down yesterday.

Small calving in the north near Evans Knoll (click to play gif).

Discharge/movement near the cork. Also it looks like the small berg in front of the cork has somewhat separated and is no longer connected to the cork, just the ice sheet (barely).

And a new rift on the Southern Ice Shelf, in between the two others.

48
Arctic sea ice / Re: The 2020 melting season
« on: April 03, 2020, 11:19:22 AM »
Extreme Fram export continues:

49
Arctic sea ice / Re: The 2020 melting season
« on: April 01, 2020, 08:19:28 AM »
Has anyone else noticed this odd protrusion between northern greenland and Svalbard island. It has been there for a while and it looks like it should just break off but it hasn't. Or is it normal?

The ice is anchored to the seabed below. In 2012 there was a similar long and relatively thin protrusion, but even as it started to shatter in July, it still held on for a while even as the part connecting it to the mainland broke off: https://worldview.earthdata.nasa.gov/?v=269947.6895835763,-1001118.4511475239,925307.6895835763,-656030.4511475239&p=arctic&t=2012-07-20-T10%3A00%3A00Z

You can see there is an area of shallow water around there too:

50
Greenland and Arctic Circle / Greenland 2020 Melting Season
« on: March 24, 2020, 08:40:12 AM »
Since we clarified that the SMB thread should be for SMB data/discussion only, I am making a general-purpose melting season thread for Greenland like from last year.

I'd like to start by asking wtf is going on in the Freya Glacier webcam? Am my eyes deceiving me or was there a lot of snow melting yesterday despite being March and -20C?

Some resources:

SMB data: http://polarportal.dk/en/greenland/surface-conditions/ (And gerontocrat's thread)
Melt extent data and news: https://nsidc.org/greenland-today/
A webcam: https://www.foto-webcam.eu/webcam/freya1/


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