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Messages - Tealight

Pages: [1] 2 3 ... 9
1
Arctic sea ice / Re: "Stupid" Questions :o
« on: October 17, 2019, 11:43:31 AM »
you can clearly see the effect of refraction  in the photo.
The sun should be a round disk in that photo it is an oblong shape suggesting light bending from refraction.

I agree the photo shows just a refraction. If the sun would be above the horizon the ice would also be very bright, but it is dark. You must keep in mind that at 87N you are only surrounded by extremly flat and highly reflective sea ice. No mountains, trees or buildings to block sunlight. If direct sunshine hits the ice at 82N at an angle of 1-2 degrees it gets reflected and travels a few hundred kilometer further through the atmosphere. Clouds can then reflect this reflection back again towards the surface.

I so happen to have webcam footage from McMurdo Station in Antarctica from the 9th August when the sun was equally 4 degrees below the horizon and the phenomena looks the same to me.

2
The southern portion calved today.

3
Arctic sea ice / Re: AMSR2 Snow & Ice Volume/Thickness
« on: September 02, 2019, 06:54:43 PM »
Volume and thickness are the same league as 2012 and 2016, but the minimum might have already happened.

Full size images and August animation at:
https://cryospherecomputing.tk/SIT

4
Glaciers / Re: Barnes Ice Cap / Penney Ice Cap
« on: August 25, 2019, 01:19:07 AM »
Here is a high resolution Sentinel 2 animation of the retreat in the northern part. From Aug 2016 to Aug 2019 retreat ranges from about 50m on land to 130m in the lake. Or 16.6m/yr and 43.3m/yr.

Assuming a 33m/yr melt rate for the widest part it would take 750 years for the ice cap to melt away.

5
Arctic sea ice / Re: AMSR2 Snow & Ice Volume/Thickness
« on: August 02, 2019, 10:03:48 AM »
Volume and thickness were record low until the second half of the month and then lost slightly out to 2012 and 2016.

Full size images and June animation at:
https://cryospherecomputing.tk/SIT

6
Arctic sea ice / Re: AMSR2 Snow & Ice Volume/Thickness
« on: July 02, 2019, 08:41:19 PM »
Volume and thickness crashed to lowest during the second half of June. In the first half melt was apparently below average. The gif shows the Beaufort gyre in action transporting ice into the melt zone.

One should keep in mind that the product doesn't try to calculate actual ice thickness, but average thickness per ice covered gridcell. If you have an even 50/50 split of water and ice than the gridcell thickness is just 50% of the ice floes.

Full size images and June animation at:
https://cryospherecomputing.tk/SIT

7
Arctic sea ice / Re: Albedo-Warming Potential
« on: June 17, 2019, 06:26:31 PM »
Did you submit to the SIPN? The site seems abandoned, no way to know the participants of course...

I did submit my forecast. The June Report is scheduled to be released on the 21 June 2019. It seems like the whole ARCUS (Arctic Research Consortium of the United States) website was taken offline, not just SIPN.

8
Two years ago I spotted quite big icebergs in the lake, but just like you didn't find a name.

old thread:
https://forum.arctic-sea-ice.net/index.php/topic,2149.0.html

9
Arctic sea ice / Re: Albedo-Warming Potential
« on: June 16, 2019, 02:43:51 AM »
You are right. All negative anomaly isn't in regions that affect the central Arctic.

Despite currently eastern winds in the Beaufort Sea, the ocean current aka Beaufort gyre still pushes the warm water west/north-west. In July and August we should see strong bottom melt in the central Arctic north of Wrangel Island. I don't think it quite reaches the North Pole.

I predict the September minimum to match 2012/2016 if AWP continues this way or a mean 2010s area/extent if conditions go worse.

10
Arctic sea ice / Re: Albedo-Warming Potential
« on: June 15, 2019, 10:18:05 PM »
After a short drop 2019 is back to challenge 2016 for 1st place in accumulated AWP. All thanks to the recent melt pond surge. But the Beaufort Sea still leads all regions by a wide margin because open ocean is darker than melt ponds.

The Beaufort seems to have exceeded the Y axis on the daily anomaly graphs, not sure if that value can be easily changed or if this would be problematic for older graphs which have the current Y axis maximum.

It was an easy fix.

11
Tealight, bear in mind that in some years in August the sea ice disappears from the inner bay, and all the icebergs are swept away. I think this happens every couple of years, but haven't done the stats. This is discussed somewhere upthread. My pet theory was that the massive iceberg jam stuck in sea ice could delay calving processes and even possibly slow the glacier down slightly. Never tested it though.

Oren, you are talking about recently calved icebergs. I was talking about icebergs that have already been swept away from the glacier. About 100km further south the icebergs are piling up like Tetris blocks. They just don't magically vanish  once a latitude line is full. There is still around 1800km2 (30*60) of space for new icebergs, but maybe 600km2 has already been tightly piling up.

12
Since the tongue separation in 2012 Zachariae Isstrøm has been continuously pumping out icebergs in the 100m to few kilometer size. Due to it's location behind an island chain these icebergs have very little chance to escape to the open ocean and melt in the North Atlantic. Today I want to share some images of the giant Tetris field Zachariae is creating.

The bottom of this field is over 100km further south and blocked by it's former giant ice tongue. Probably the southern 30km of this space is already full with tightly stacked icebergs and more are coming down every year. For now it doesn't look like the blockage is going to clear out. The only way to prevent further filling up of this space is local melt. If the heavy calving of the glacier continues it might completly clog up this entire space with icebergs over the next decade.

13
Arctic sea ice / Re: Albedo-Warming Potential
« on: June 08, 2019, 01:07:52 AM »
The recent warm temperatures over the central Arctic did not result in a significant albedo drop. I suspect the peak sunshine intensity this far north is just too low to force widespread meltponding. Without imported heat from the south it just stays an iceblock. It's like trying to melt some metal in a common household oven. You can heat it for a few days, but you never melt the surface unlike a few minutes in a furnace.

The absence of importet heat means 2016 won the battle for first place and in a few days begins the dominance of 2012 until the end of the melting season.

14
Arctic sea ice / Re: Updating the ASIG
« on: June 04, 2019, 01:13:32 AM »
There also seems to be a problem with DMI no longer updating the Greenland maps and graphs they had on their website. Polarportal has the same images, but their addresses are dynamic (ie each date has its own file name) and so I can't hotlink to them. I wish I knew how to write scripts...

I haven't used googlesites in a while, but I know how to write html image references with a variable url. The following solution works with a generic html file (copy everything into a text file, rename ending to html and open in a browser)
You can try putting it into an HTML box in google sites and maybe it will work.

Code: [Select]
<html>
<img id="Greenland">

<script>
var today = new Date();
yesterday = new Date(today - 68400000); //set off time in milliseconds
var dd = String(yesterday.getUTCDate()).padStart(2, '0');
var mm = String(yesterday.getUTCMonth() + 1).padStart(2, '0'); //January is 0!
var yyyy = yesterday.getFullYear();

yesterdaystring = yyyy+mm+dd;

var imageid = "http://polarportal.dk/fileadmin/polarportal/surface/SMB_map_LA_day_EN_"+yesterdaystring+".png";
document.getElementById("Greenland").src = imageid;
</script>

</html>

Edit: changed getDate() to getUTCDate() for same execution worldwide

15
Arctic sea ice / Re: What's new in the Arctic ?
« on: June 02, 2019, 01:11:20 AM »
RE Tealight #348
Nice work!  That would be great addition to NSIDC website.

The NSIDC has the sea ice comparison tool, but it takes forever to load. Another issue with it is showing only extent and not sea ice concentration.

http://nsidc.org/arcticseaicenews/sea-ice-comparison-tool/

16
Arctic sea ice / Re: AMSR2 Snow & Ice Volume/Thickness
« on: June 02, 2019, 01:01:30 AM »
Volume continued below the mean, but thickness went up at the end of the month. It looks like the Beaufort gyre compacted sea ice against eastern Siberia and Hudson Bay ice was compacted against the southern coast.

Full size images and May animation at:
https://cryospherecomputing.tk/SIT

17
Arctic sea ice / Re: What's new in the Arctic ?
« on: May 31, 2019, 12:33:55 AM »
I made a quick and lightweight sea ice comparison page for the entire NSIDC data set. At the moment it's just for the 1st of the month, but soon I add the 15th of the month as well.

https://cryospherecomputing.tk/PastSIC

18
Antarctica / Re: Antarctic Icebergs
« on: May 28, 2019, 10:11:01 PM »
A68A rotation continues in the same spot. Animation beween 3rd May and 28th May.

19
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: May 22, 2019, 11:43:21 PM »
Even if we have slightly more melt than precipitation right now. Most losses are happening in June and July. On the attached gif I compared the 10th July 2012 with today. It almost looks like we have no melt right now.

20
Arctic sea ice / Re: The 2019 melting season
« on: May 16, 2019, 05:03:28 PM »
Now in mid-May, we are just over a month away from peak insulation. The time the northern hemisphere has it's greatest warming potential. Including Greenland, snow cover extent is still around 50% more than sea ice extent. From an overall albedo perspective this makes sea ice look less relevant than snow cover. At this time 2012 dived to record low snow extent in June and attacked the ice from all sides with continental heat to force widespread meltponding and eventual record low sea ice extent.

This year seems to have pretty average snow cover more in line with 2015 and 2016, but below 2017 and 2018.

21
Antarctica / Re: Sea Ice Extent around Antarctica
« on: May 15, 2019, 11:59:22 PM »
Nice analysis oren. As in my regional snow cover analysis some charts are very hard to read due to the high year to year variability. To me it looks like the Bellinghausen & Amundsen Sea have a downward trend for day 133 and day 365. The highs of the 2010s are the lows of the 1980s. The lines for day 166 to 274 are just to noisy to see anything.

Can make some 365 day charts showing decade averages? They have less noise and melt events don't have to fit into an exact month or specific day.

22
Antarctica / Re: Sea Ice Extent around Antarctica
« on: May 12, 2019, 06:03:23 PM »
Hi Rich, the current low sea ice extent is caused mostly by the Weddel Sea (see picture below). The Ross Sea is around average. I would say the cause is the current weather pattern. The circumpolar winds are very weak and plenty of mid latitude warmth reaches further south. Somewhere I read that the Antarctic Circumpolar Current is gradually moving south over the last few years, but I can't remember the source.

23
Arctic sea ice / Re: Albedo-Warming Potential
« on: May 05, 2019, 11:18:23 PM »
Thanks everyone. I can confirm it feels good to beat major international organisations like NASA, MetOffice and ecmwf.

Tealight, you derive AWP using sea ice area and then use this as a basis to calculate the energy available to reduce sea ice thickness ? How do you translate reduced thickness into resulting sea ice area and extent? A sea might have remaining ice piled up in one area  or spread out giving a higher extent value due to varying winds and currents?

Technically I keep track of two sea ice concentration values. One to calculate the melt (using SIC from previous years) and another calculated from thickness. The second one is the final model output. The additional thickness step makes the model more robust against flashes of low SIC like short term melt ponds.

For the Antarctic I used the following formula to get the best results:
SIC(%) = (Thickness(m)^1.3) / 0.0155

Thickness(m)   SIC value (%)
1.4   100
1.25   86
1   65
0.75   44
0.5   26
0.25   11
0   0

anything over 1.4m stays at 100% SIC.

24
Arctic sea ice / Re: Albedo-Warming Potential
« on: May 05, 2019, 08:27:26 PM »
Very popular here are the sea ice minimum and maximum polls guessing the correct sea ice extent in millions of square kilometer. A more scientific oriented version of it is the Sea Ice Prediction Network: https://www.arcus.org/sipn
This year was the second time they made a trial run to forecast the Antarctic summer minimum and I participated (as Nico Sun) with a forecast model derived from this Albedo-Warming Potential model. The underlying physics are the same. The major difference is that instead of accumulating an energy value in a grid cell, this energy is used to calculate the sea ice thickness loss. Additionally I added an outgoing infrared radiation variable to get an actual energy balance.

With the post season report released I can proudly claim victory not only in overall area values, but also on a regional scale with the lowest error over the entire 3 month forecasting period. This is in part thanks to the real world usefulness of the AWP model and in part due to the submission deadline of 1st December. Some other team's can only run their models at the beginning of every month and had to use October data for their model initialization. I attached the two most relevant figures, but recommend to read the whole report.

Full 2018-2019 post season report
http://www.climate.be/users/fmasson/SIPN-South_2018-2019_postseason.pdf

General SIPN south website
http://acecrc.org.au/sipn-south/


Sea Ice Loss Formula of the forecast model:

Ed = MJ_inlat,day x (1 - SIC) - MJ_out
z = Ed / Efusion

Ed = Melt energy per day
MJ_in = incoming solar radiation per m2
MJ_out = outgoing infrared emmision per m2
SIC = sea ice concentration
z = thickness loss in m
Efusion = Enthalpy of fusion per m3

25
Antarctica / Re: What's new in Antarctica ?
« on: May 04, 2019, 08:55:08 PM »
The visualization is great but I have some questions:
At what cross-section was the data measured? At the grounding line?
Is PIG really that wide? I thought it was 40km.
And some of the heights seem strange. Petermann, NG and even PIG could float with these heights.

The Grounding line isn't very smooth and changes constantly. I did just draw a line behind the glacier terminus where the bedrock is more or less a valley. Pretty much all of the west antarctic region is below sea level. You can't use below sea level as a definition, because then Pine Island and Thwaties are the same glacier.

Yes, Petermann, NG and PIG all float at the terminus. Do you think another thickness line would fit into the graphs? It's already quite crowded and the thickness data is even more unreliable / out of date.

PIG 40km is about right for the flat floating part, but not the whole valley which includes ice from the sides coming down.

26
Antarctica / Re: What's new in Antarctica ?
« on: May 04, 2019, 06:29:14 PM »
I made some Glacier size comparison charts featuring Greenland & Antarctic Glaciers. I hope it better visualizes how much ice is exposed to ocean water than a Bedrock map. The charts shows the dimensions of the glacier front. Where the x-axis is the glacier width and the y-axis is the glacier height.

https://cryospherecomputing.tk/Glacier-size

(same post as what's new in Greenland)

27
Greenland and Arctic Circle / Re: What's new in Greenland?
« on: May 04, 2019, 06:28:40 PM »
I made some glacier size comparison charts featuring Greenland & Antarctic Glaciers. I hope it better visualizes how much ice is exposed to ocean water than a Bedrock map. The charts shows the dimensions of the glacier front. Where the x-axis is the glacier width and the y-axis is the glacier height.

https://cryospherecomputing.tk/Glacier-size

28
Antarctica / Re: Antarctic Icebergs
« on: May 03, 2019, 08:18:24 PM »
Now A68-A is just 5.5km away from the islands. I wonder if it's actually going to collide with the island itself. According to the Bedrock map the area is quite shallow, but it might be wrong. The small part that broke off early (A68-B) is currently in 40-50m deep waters.

29
Arctic sea ice / Re: AMSR2 Snow & Ice Volume/Thickness
« on: May 03, 2019, 11:29:48 AM »
Another month of low overall gain, but above average thickness.

Full size images and April animation at:
https://cryospherecomputing.tk/SIT

30
Arctic sea ice / Re: Albedo-Warming Potential
« on: May 03, 2019, 02:21:56 AM »
No surprise that we're tracking to get a similar anomaly in the Bering as last year, iirc last years ~250 mj/m2 was basically double any prior year.

Tealight, my understanding of the 'potential' part of AWP is that the calculation doesn't account for weather, correct? A cloudy season and a sunny season with similar extent would produce similar AWP numbers but would experience different actual warming?

You are right that it doesn't account for weather and doesn't calculate actual warming. The data presented here is just a model to rank years against each other instead of a daily or monthly minimum number. It also quantifies the actual surface albedo change in the Arctic. However, the underlying physics are good enough for real applications. Maybe I can give more information tomorrow.

31
Arctic sea ice / Re: Albedo-Warming Potential
« on: May 01, 2019, 01:05:08 AM »
Just in time before the May melt ponds start I created the regional anomaly charts. Just like last year almost all of the early accumulated AWP anomaly comes from the Bering Sea, but this year none of the regions is in the negative.

https://cryospherecomputing.tk/NRTawp

32
Arctic sea ice / Re: Albedo-Warming Potential
« on: April 27, 2019, 07:04:48 PM »
Before working on all region graphs I created another section for the High Arctic. This one should be more useful for determining the record low in September. It only includes the following regions: Kara Sea, Laptev Sea, East Siberian Sea, Chukchi Sea, Beaufort Sea, Canadian Archipelago, Central Arctic.

For the high Arctic 2012 still holds the record high followed by 2016 in second and 2007/2011 tied in third. The far higher average ice cover also significantly increases the gap to a completly ice-free state. On one hand the 2010s just reach 40% of the ice-free conditions compared to 61% for the whole Arctic. But on the other hand the 2010s absorb 32% more than the 1980s. For the whole Arctic it's just 15% more. So the last ten years really impacted the high latitudes more than the lower ones.

https://cryospherecomputing.tk/awp

Note: Before doing this recalculation I increased the ice albedo from 80% to 85% relative to ocean albedo. This is more in line with the values I measured from satellite images. The result is slighly lower absolute values, but hardly any change to anomaly values. The near-real time data will be updated tomorrow.

33
Antarctica / Re: What's new in Antarctica ?
« on: April 23, 2019, 01:49:47 AM »
The Antarctic Bedrock data was over 10 times harder to align than Greenland. There are hardly any landmarks, just plain white and with fast ice or ice shelfs you don't even know where the land begins. I had to use huge area images to align islands and then cut it down to individual glaciers. The bedrock resolution is just 1km/px as opposed to 0.15km/px for Greenland data.

https://cryospherecomputing.tk/Bedrock-Antarctica

34
Greenland and Arctic Circle / Re: What's new in Greenland?
« on: April 22, 2019, 12:08:53 PM »
Did anybody say their favorite glacier isn't featured? No? Well here is all of Greenland Bedrock anyway.

https://cryospherecomputing.tk/Bedrock

35
Arctic sea ice / Re: Albedo-Warming Potential
« on: April 21, 2019, 11:58:18 AM »
Oren I just finished summarizing the regional data. The Bering Sea and Beaufort Sea are already very close to icefree. If I do another central Arctic Graph for the pack ice region then they have to drop as well. In my view the Barents Sea is just like Greenland Sea, mostly for export of central Arctic Ice. The Bering Sea is too far south to affect the Central Arctic, at most it affects southern Chukchi Sea but not more. 2012 has shown that the Pacific side of the Arctic can get a huge melt even with a record bad Bering Sea melt.



36
Arctic sea ice / Re: Albedo-Warming Potential
« on: April 20, 2019, 05:33:12 PM »
Two images to show the current massive regional differences. First a Peak Watt map showing maximum solar intensity at noon. It might be important to get the initial punch to turn snow into a melt pond. The high Arctic never receives this intensity and relies entirely on imported warmth.

For daily averaged energy values the Sea of Okhotsk, closely followed by Bering Sea currently absorbs over ten times more energy than the central Arctic.

Arctic mean: 6.1 MJ/m2

Sea of Okhotsk   18.711
Bering Sea   16.264
Hudson Bay   4.977
Baffin Bay   9.695
East Greenland Sea   8.159
Barents Sea   8.567
Kara Sea   2.753
Laptev Sea   2.387
East Siberian Sea   2.462
Chukchi Sea   3.255
Beaufort Sea   2.598
Canadian Archipelago   2.75
Central Arctic   1.601

37
Greenland and Arctic Circle / Re: What's new in Greenland?
« on: April 20, 2019, 02:50:03 PM »
Just awesome Tealight!

May i suggest using a bigger font and a visual separation (thin line perhaps) between the glaciers and centring of the pics. Would make it even more beautiful imho.

Technically all pictures are centered (if you span the browser over two monitors) The Petermann Glacier has a different aspect ratio and the image overlay code needs a point zero which is set for the widest images. So all image overlays have to begin at the same position.

I try to add a visual separation, but the font is already quite big imo. After loading the webpage from the web and not locally I noticed it has a loading time. With 20MB it's already a decent size. Thus I probably create a separate page for Antarctic Glaciers.

Tealight...you should get an award for this work.

For this? It's just using some web templates, downloading other peoples work and aligning two images in a paint program. All in all two afternoons of work.

38
Greenland and Arctic Circle / Re: What's new in Greenland?
« on: April 20, 2019, 11:37:05 AM »
New Bedrock overlay page for all of Greenlands major glaciers.

https://cryospherecomputing.tk/Bedrock

39
Greenland and Arctic Circle / Re: Bedrock overlay poll
« on: April 20, 2019, 11:34:33 AM »
Thanks everyone for voting. As I suspected both options have a use case. The problem with combining them was that the template for the image overlay slider and the template for the range slider both had "slider" in the name and interferred with another. I solved it by setting the opacity with a number input field and a button.

The test pages are now removed and the overlays have an offical page:
https://cryospherecomputing.tk/Bedrock

40
Greenland and Arctic Circle / Bedrock overlay poll
« on: April 14, 2019, 03:40:48 AM »
I've often seen users asking about a glaciers bedrock elevation to estimate future retreat. Then some veteran users post a bedrock map, but it's still difficult to compare it to current satellite images. Therefore I want to build a bedrock overlay webpage for all major glaciers. However I'm not sure which of the two presentation styles is better.

You can vote for both options if you have no major preference.

Horizontal overlay
https://cryospherecomputing.tk/Test1

Full image Opacity
https://cryospherecomputing.tk/Test2

41
Arctic sea ice / Re: Albedo-Warming Potential
« on: April 11, 2019, 12:11:44 AM »
Some feedback - not sure if you are aware but images don’t seem to load on mobile. When I hold down on the empty space and ask to open image though, it does show up on the next tab.

I still have to upload daily updated images to google drive and insert a shared link into the website. (I don't know yet how put them on the github server)

Oren had the exact same problems and it had something to do with his googleaccount. Can you try opening the webpage in incognito mode?

42
Arctic sea ice / Re: "Stupid" Questions :o
« on: April 10, 2019, 02:25:57 AM »
With the high (relative) levels of melting in the Arctic recently, the flooding that occurred in the NE USA, and the jet stream in that area..... I was wondering whether the water in the clouds came from the melting in the Arctic region, traveled South, then dropped it on the US?

It seems plausible in my head, but is that what happened?

The water generally comes from the warm & wet south, especially in spring. However without cold air from the Arctic the moisture wouldn't come down as heavily and cause flooding. The cold & dense air causes the warm & less dense air to rise, kind of like a mountain. As the warm air rises it cools, can't hold the moisture anymore and develops thick clouds & rain. On earth.nullschool.net I have often seen constant weather front change in the north eastern USA and south eastern Canada. A few days of warm & wet Atlantic air followed by cold air from the Arctic.

Good overview on wikipedia:
https://en.wikipedia.org/wiki/Cold_front

43
Arctic sea ice / Re: Albedo-Warming Potential
« on: April 07, 2019, 10:37:28 PM »
Thanks for the patience and support everybody.

Here is the AWP NRT link:
https://cryospherecomputing.tk/NRTawp

By the way I added a website icon which should be displayed next to the page name in the tab. Right now it's some melting sea ice in Beaufort Sea (2016) at super low resolution. Maybe I make a logo in the future.

44
Arctic sea ice / Re: Albedo-Warming Potential
« on: April 07, 2019, 12:11:26 AM »
The new near-real-time Albedo-Warming Potential script is programmed. If it updates tomorrow as intended I post the website link. The regional data has to wait until I structure the regional data from the previous 40 years.

45
Arctic sea ice / Re: Latest PIOMAS update (April 2019)
« on: April 04, 2019, 01:21:33 AM »
question to the specialists, theoretically i can calculate but there may be hidden traps for a layman, hence i thought to ask:

how much thicker must the ice be to keep the same volume while loosing > 1'000'000km2 in the 2 other dimensions. i assume extent and area won't produce the same result and since i'm not privy with the calculations, i ask that question.

trigger for the question is that each time after a month of steep losses i wonder how it can be that volume could keep level or even increase, is it realistic that the reminder at the same time would grow that much in thickness ?

after all the real area of thickness increase is relatively small, since i think that if the ice is melting at the periphery, there must be some significant range in the midle between the pole and the periphery where ice is melting, just not to zero, keeping thickness and another part where thickness is growing only a little, hence there is not much area left where ice would grow so much to compensate for all the losses.

so much my logics which may be wrong (apparently) and i want to know why i'm apparently erring.

In simple terms the ice that melts at the edge must be replaced by new ice in the centre. The major problem here is that everyone is only publishing average thickness values for the entire Arctic. The ice that was in Bering Sea and Guld of St Lawrence was probably just 10-20cm thick. So 20cm*1million km2 divided by 10 million km2 for the central Arctic gives you a thickness increase of only 2cm.

PIOMAS is really bad at getting the ice edge right, most of all soutwest Greenland which is pretty much never frozen. It's one of the reason why I developed the high resolution "AMSR2 Snow & Ice Volume". It's not as good for the very thick central Arctic, but much better for thin ice and defining an ice edge.

https://cryospherecomputing.tk/SIT

46
Arctic sea ice / Re: Albedo-Warming Potential
« on: April 03, 2019, 01:45:58 AM »
Stumbled on to it while looking at your AMSR2 tab and I have to say it is absolutely beautiful in its presentation.

Please keep up the amazing work and cannot wait for the near real time data additions!

Thanks Viggy, it really means a lot to me. The presentation takes up about 75% of the time, but is also the most important part.

47
Arctic sea ice / Re: Albedo-Warming Potential
« on: April 03, 2019, 01:19:03 AM »
BAM! Two years have gone by without an update.

I finally have the processsing power and coding skills to take the AWP model to where I intended it to be. Instead of only calculating the anomaly of potentially absorbed solar radiation. I now calculate the raw accumulated values, the anomaly and a percentage of the current year to the maximum possible (complete Ice-free conditions). From the 1980s to 2010s this percentage has gone up from roughly 52% to 62%. Generally from August onwards the Arctic is 75% icefree and from September onwards the Arctic is 90% icefree.

Everything is now much better presented with interactive graphs and sliders to compare individual years. The regional data is already calculated, but needs even more work for proper presentation. Near-real time data for 2019 is in the works too.

Fancy new webpage:
https://cryospherecomputing.tk/awp

Still too short documentation of AWP model:
https://cryospherecomputing.tk/doc.


48
Arctic sea ice / Re: AMSR2 Snow & Ice Volume/Thickness
« on: April 03, 2019, 12:49:18 AM »
<snippage>Full size images and February animation at:
https://cryospherecomputing.tk/SIT
Thanks for this Tealight. I carelessly missed the February animation. Can I download it from somewhere?

Sorry, but to keep the update process simple I only create one gif file per month which always replaces the old one.

49
Arctic sea ice / Re: AMSR2 Snow & Ice Volume/Thickness
« on: April 02, 2019, 11:16:09 AM »
Only a moderate thickness increase and a complete volume stall in the second half of March, probably caused by the Bering Sea and Gulf of St Lawrence melt out.

Full size images and March animation at:
https://cryospherecomputing.tk/SIT

50
NOAA snow cover is finally showing heavy losses in western Canada. The southern Rockies however are still snow covered.

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