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Messages - oren

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1
Arctic sea ice / Re: The 2020 melting season
« on: Today at 11:02:23 AM »
It could also mean the ice surface has become very wet, registering as a drop of area but not reaching thresholds for extent to drop.

2
Arctic sea ice / Re: Glossary ... for newbies and others
« on: Today at 04:40:55 AM »
Added.

3
The weird order of things is:
NSIDC extent > AMSR2 extent
AMSR2 area > NSIDC area

I browsed through the data files provided by Wipneus for NSIDC and for UH AMSR2 (not the same as JAXA, but hopefully a good proxy for finding differences from NSIDC). On July 1st this year NSIDC overestimated extent by 725k, while last year on July 1st the overestimate was 665k. The difference seems small but with some years bunched together this may explain the difference in the rankings. There are positive and negative differences in several regions, but it seems the biggest difference is in the Greenland Sea, where last year the overestimate was 37k and this year it's 101k.
Looking at the NSIDC and JAXA extent maps the visual difference does not jump out at me. Of course it does not help that the orientation is upside down. But in any case, I think this is all just noise. The rankings magnify small differences which will evolve through the season in any case.

4
Consequences / Re: COVID-19
« on: July 02, 2020, 10:21:22 AM »
IMHO in a room with masked people, I would personally prefer no forced mixing of the air. IMHO a ceiling fan will increase risk rather than decrease it.
I would also suggest if this is to be developed further it should go into a different thread.

5
Policy and solutions / Re: Renewable Energy
« on: July 02, 2020, 12:22:22 AM »
KF does not cherry pick per se, but his posts are 99% positive. An important service, nothing wrong with that, but don't expect to get the other side of the story.

Primary energy is not a good measure, it will forever undercount renewables which do not produce waste heat.

Re wind and solar only luxury, nah, that's old news. 4h batteries (and pumped up hydro) can do wonders with these sources, and when complemented by dispatchable sources (gas, hydro) renewables save lots of emissions and provide energy reliably.

6
I did vote for July based on the stable arch and cold winter, but given the slow peeling in early June I really thought it was gonna blow. In late June it was a goner but the wind did not cooperate to give it the coup the grace. So funnily enough, my original vote turned out to be correct after all. Even a stopped clock and all that.

7
Arctic sea ice / Re: Nullschool Forecasts
« on: July 01, 2020, 08:26:27 PM »
FG, are you ok? I got hooked on your posts here.

8
Arctic sea ice / Re: The 2020 melting season
« on: July 01, 2020, 07:16:39 PM »
Browsing through Worldview I noticed the situation in Dmitry Laptev Strait. What was still fast ice 5 days ago is now decimated at an alarming rate. I looked at 2005-2019 on this date , and only 2016 had the ice broken and melting along the whole strait, and no year at all had an open passage through the strait.
Click to animate. 28th and 29th removed due to clouds. A lot of ice disappears on the last day - a testament to the crazy temperatures.

9
Arctic sea ice / Re: September predictions challenge 2020
« on: July 01, 2020, 02:37:27 PM »
JAXA: 3.5-4.0 (medium)
NSIDC: 4.0-4.5 (high)
PIOMAS 4.25-4.75 High
July:
JAXA: 3.5-4.0 (high)
NSIDC: 3.75-4.25 (medium)
PIOMAS 3.75-4.25 (medium)

10
Dropped two bins at once to 3.75-4.25. Not sure what the PIOMAS model will do but the Siberian ice is cooked, and the forecast calls for warm sunny weather and some export. Passing 2019 should not be hard, though passing 2012 is a different story.

11
I've taken down one bin to 3.75-4.25. Daring, but I think the current ice condition and forecast call for some daring.

12
I am also keeping 3.50-4.00, but I think the probability of it happening has grown significantly. Higher chance of downside than upside surprise IMHO. However to break 2012's record also requires perfect compaction around the minimum, which I think greatly lowers the probability. I wouldn't be surprised by a new area record though.

13
The site is legit. This issue with https started yesterday, hopefully it will be resolved soon. But I am sure other sites can be used as well for the same purpose.

14
Arctic sea ice / Re: The 2020 melting season
« on: July 01, 2020, 08:24:05 AM »
VAK, while I appreciate your posts, you must remain on-topic in this thread. This discussion/speculation of ice shelves and lake snow effect belongs elsewhere. I will have to take more drastic measures if this continues.

15
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: June 30, 2020, 08:56:36 PM »
So a small patch of ice in the middle of the ocean will melt at the same rate as when the whole ocean is filled up?
I should think higher air temperatures can easily attack the ice in such a case, while OTOH when it is surrounded by other ice it is much more protected. Besides, any movement of the lone patch of ice to a nearby open water region will result in its quick demise. Waves are also an important factor. Thus Arctic melting is not two-dimensional at all, and a lot depends on what goes on in adjacent regions of the Arctic ocean.

16
Arctic sea ice / Re: Glossary ... for newbies and others
« on: June 30, 2020, 07:53:39 PM »
Added both CR and hPa.

17
Most Arctic stations (except some Alaska stations for some reason) provide SYNOP reports and are available via various websites. Some use METAR instead or in addition. Warning: I have no clue what or why this is, I am just a practical user.
I personally use ogimet (a Spanish website) for individual stations. It has a map showing all stations in an area which is quite useful (and works most of the time). However, I am not aware of a list of the special instruments in  various stations.
Link to ogimet map (requires panning, zooming out and selecting desired variable such as max temp, not very friendly):
https://www.ogimet.com/cgi-bin/ogimet_nav?lang=en&lat=75N&lon=-075

Link to the reports by a specific station (Eureka):
https://www.ogimet.com/cgi-bin/gsynres?lang=en&ind=71917&ndays=30&ano=2020&mes=6&day=30&hora=15&min=13

18
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: June 30, 2020, 05:03:43 PM »
Quote
Volume will naturally taper off as it approaches zero, such that both area and volume (and thickness) reach zero simultaneously.
Why would volume naturally taper off as it approaches zero? Just to give area a respite?
It is the opposite. At a certain volume threshold the Arctic becomes practically ice-free. Once the typical thickness of CAB ice is melted during a melting season, area will crash, while some volume may be retained in very thick ice floes (pressure ridges and very old MYI).
As the freezing season becomes shorter and less powerful, and the melting season longer and more powerful, not forgetting the contribution of increased mobility and export, this inflection point is not too far off, probably a decade into the future.

19
Arctic sea ice / Re: The 2020 melting season
« on: June 30, 2020, 10:50:56 AM »
. Daily average reached incredible +28.3°C in Khatanga.

R U sure?

On wikipedia it says that the average June temperature for Khatanga is 5,7 C (average high 9,9  average low 2,6)
As unbelievable as it is, Khatanga at 72N averaged ~28C on June 29th, ~18C above the average for the date which is ~10C. The same happened on June 30th, not yet shown in the chart.
Green line is average temp, light green is climatology.

20
The forum / Re: Forum Decorum
« on: June 30, 2020, 10:19:15 AM »
Thank you gandul for your comment, and you do have a point. My view of it is as Viggy noted, "I kinda view it as misinformation (not as egregious as a denialist) that deserves to be noted as such."
Had bbr not been banned from the forum, I might have been more gentle. As things stand, I have a duty to keep him under a tight leash. Any and all references to ice ages are to be removed or highlighted as nonsense. Hudson Bay sea ice is somehow part of this, so I make sure not to leave such claims uncontested.

21
The forum / Re: Forum Decorum
« on: June 30, 2020, 08:50:56 AM »
I changed the stupid questions thread title to:
"Smart" and "Stupid" Questions - Feel Free To Ask
Hopefully this will be more inviting to newbies and old-timers who have questions to ask.

22
Arctic sea ice / Re: MOSAiC news
« on: June 30, 2020, 08:24:12 AM »
I think 1m was the thickness during deployment, in October.

23
Arctic sea ice / Re: HYCOM
« on: June 30, 2020, 03:08:07 AM »
One thing that PIOMAS does is to model a distribution of ice thicknesses in each grid cell. This enables taking stock of pressure ridges, which contain a lot of volume though only cover a small area. The PIOMAS map shows the average for each cell, but the output files contain the distribution, which Wipneus graphs from time to time.
Looking at the Mosaic buoys, one of them was placed on a 7m thick floe, a real life example of uneven thickness of floes in the same vicinity.
I am sure Hycom models hydrology much much better, but not so sure how well it performs with ice thickness and transport.
Since PIOMAS assimilates NSIDC concentration data, it is rare (but happens) for it to show ice where none exists. I think this mostly stems from coarse resolution and will tend to disappear, so errors don't accumulate. But my knowledge of PIOMAS inner workings is very limited, I just use some of the output provided by Wipneus.

24
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: June 30, 2020, 01:10:14 AM »
I think the main factors are declining winter volume (not listed but affected by Atlantification and Pacification and open water and heat content in September), Mechanical as listed, Albedo/Surface Melt as Listed, plus warming continents (part of Weather).

25
Arctic sea ice / Re: The 2020 melting season
« on: June 29, 2020, 07:52:20 PM »
This should be discussed in another thread.

Arctic wildfires and their effect on sea ice

26
The forum / Re: Forum Decorum
« on: June 29, 2020, 12:44:16 PM »
I think there are certain respectable users who would be encouraged to post more if they had a blog-like thread rather than a free-for-all thread, and who would increase the overall value of the forum, though at some cost to free speech. But this depends on technical capabilities which I am guessing the forum doesn't have.

27
The forum / Re: Forum Decorum
« on: June 29, 2020, 08:39:08 AM »
In any case, Neven runs this forum and has stated clearly he desires the political section to be a part of it (I have argued to the contrary to no avail, so I remember the result well).
For peace of mind, be aware there are some scientists with known identities that post here from time to time, and I doubt a scientist can be held accountable for stuff others post, especially in threads he or she is not even participating in and has never read. Never mind that some radical stuff gets posted from time to time in the science threads and certainly in the policy/solutions/consequences threads, so anyone who is concerned by radical posts would have the same problem after the political section was cast away.

28
Arctic sea ice / Re: The 2020 melting season
« on: June 29, 2020, 08:30:56 AM »
To be clear: PIOMAS is a model but assimilates a lot of measured data. Cryosat is a measurement but relies on a lot of models for interpretation of the radar signals (e.g. unknown snow thickness). Both have their upsides and downsides, but certainly when Cryosat says volume was much lower than PIOMAS this is a very important piece of information. Obviously a biased poster would not be stressing that point, but all are already aware of the bias so should not be discussed here.
I should note the low Cryosat volume was discussed at the time in the "Near Real Time Sea Ice Volume" thread, which I have only discovered after the discussions were over. The mapped comparison with PIOMAS was posted in the "PIOMAS vs. Cryosat" thread.

29
Policy and solutions / Re: Tesla glory/failure
« on: June 29, 2020, 12:49:38 AM »
Quote
There's a little known aspect
I bet speculators and hedge funds are filled to the brim with TSLA shares, waiting for the promised buyers. This can cut both ways.

30
Consequences / Re: COVID-19
« on: June 29, 2020, 12:15:33 AM »
Re US death rates, I will take the other side of that bet. We are still seeing the first wave signal, and it is quite obvious that the initial crest of that wave was much higher than the official data shows. The second wave just started, but the signal should definitely be visible in the second half of July.
Yes, treatment protocols are better, and many older people are protecting themselves, but this will not be enough IMHO.

31
Consequences / Re: COVID-19
« on: June 28, 2020, 05:30:09 PM »
So? Do you expect Deaths and hospitalizations to continue falling?

32
Arctic sea ice / Re: The 2020 melting season
« on: June 28, 2020, 09:56:55 AM »
Add to that Isachsen, on Ellef Ringness Island at the CAA border of the CAB, reporting ~14C and dewpoint ~7C, with the wind at ~13kt from the east.

33
Arctic sea ice / Re: HYCOM
« on: June 28, 2020, 09:46:48 AM »
If I may add, the ice distribution in Hycom is very weird, with all the thick ice up to 5m bunched very near to Greenland and the CAA, and the rest of the CAB at a measly 2-2.5m. I find it very hard to believe this represent a true gradient, and Cryosat-SMOS does not support this either.

It now occurs to me that an ASCAT animation, showing where the old ice is and covering the period leading up to mid-April, could be very useful here as well. There should some animations available that uniquorn has posted through the winter and spring, will look for a suitable one.

34
Arctic sea ice / Re: HYCOM
« on: June 28, 2020, 09:41:27 AM »
Thank you interstitial for the wealth of data.
I edited the comparative post above and added a Cryosat-SMOS map for mid-April. I am having a hard time comparing them directly but maybe you can do the same visual comparison you did between PIOMAS and Hycom.
I am adding here two maps of April monthly anomalies compared to 2011-2018, one from PIOMAS and one from Cryosat-SMOS, provided by the Polar Science Center as part of their PIOMAS April update. These can help in finding the differences. I wish such a map in the same format  would be available from Hycom, but that would be too much to ask.

35
The forum / Re: Forum Decorum
« on: June 28, 2020, 08:45:24 AM »
The trouble is pure political debates rarely lead to agreement and mostly serve to alienate people, who then carry over the resulting bitter feelings to the rest of the forum. Often this leads to enmity and people leaving. It should have been a separate forum with different user names.
The first such thread was Russiagate, which served absolutely no good and had zero correlation with forum scope, but created two very vocal groups who "hated" each other (and TBH lost a lot of respect from other posters in the process).
The climate-related issues mostly have a consensus on this forum (for good reason). The only divisive issue is the Green BAU approach, but that has to be debated within the forum.
This might be water under the bridge at this point.

36
Arctic sea ice / Re: The 2020 melting season
« on: June 27, 2020, 08:15:54 PM »
No new sea ice is created in the ESS in June. Too warm. But why do you think this is refreeze ice? Maybe the recent dispersion into the ESS, caused by the storm, is confusing things?


37
The lesson here is, the Fed will always bail out the stock market because they (still wrongly) think this is what represents the economy.
So very true.

38
The politics / Re: The Trump Presidency
« on: June 27, 2020, 01:34:43 PM »
He will run. Such narcissists are rarely aware when their situation is worsening (if indeed it is).

39
With the average SMB gain at nearly 400GT, it would take a very exceptional year to reach negative territory. So far this year is not showing the signs, but surprises can happen.

40
The rest / Re: The off topic off topic thread
« on: June 27, 2020, 08:24:54 AM »
I strongly dislike beer, mostly because of the bitterness... But I don't consume alcohol except a rare glass of wine.

41
Arctic sea ice / Re: HYCOM vs ASMR2 Imagery
« on: June 27, 2020, 08:16:53 AM »
I have not looked. I would appreciate a posting of Hycom Apr 15th and Cryosat Apr 15th side by side somewhere, maybe in the new Hycom thread. I would look for differences where the anomalies were supposed to be - near Svalbard, in the Beaufort, and in the ESS.

42
Permafrost / Re: Arctic wildfires and their effect on sea ice
« on: June 27, 2020, 08:09:42 AM »
Extreme fires erupt in the Arctic Circle
https://mashable.com/article/arctic-fires-extreme-2020/

Quote
For the second straight year, an unusually large number of intense fires have ignited in the Arctic Circle, the polar region atop Earth.

It's now been anomalously warm in Siberia for nearly six months, and temperatures likely eclipsed triple digits in a Siberian town last weekend — setting a heat record for the Arctic Circle. This streak of warm and hot conditions has set the stage for blazes to torch the dried-out region. Last year, unprecedented fires burned in the Arctic Circle, and new data from Copernicus, the European Union's earth observation agency, show the number and intensity of fires is similar in 2020.

The robust blazes are problematic because burned forests and vegetation release copious amounts of heat-trapping greenhouse gases into the atmosphere (CO2, for example, is a primary ingredient in smoke), particularly when thick mats of decomposed, carbon-rich vegetation, called peat, ignite. Of the 18 years researchers have used satellites to closely monitor Arctic fires, 2019 and 2020 have emitted more CO2 into the atmosphere than the previous 16 years combined, said Thomas Smith, an assistant professor in environmental geography at the London School of Economics.

"The two years together is quite alarming," said Smith. "I don't use that word lightly."

Quote
As the Earth's climate continues to relentlessly warm, the recent fires could be a harbinger of substantially more burning in the Arctic Circle. Yet, the 18-year wildfire satellite record (started via NASA satellites in 2002) is still too short to conclude with certainty that these recent fire years are evidence that the fire regime in the Arctic Circle has dramatically changed. Still, there's growing evidence that change is afoot in forests and tundra atop the globe.

"With confidence, we can say that this does appear to be an increasing trend of fire," said Jessica McCarty, an Arctic fire researcher and assistant professor in the Department of Geography at Miami University. "There’s some shift occurring."

She emphasized that recent fire activity in the region "is an interesting finding," but it will take years of further observation to confirm if it's part of a big, sustained trend. Fire seasons are naturally cyclical, meaning there can be bigger fire years followed by less intense periods as the landscape recovers and vegetation regrows. Additionally, Siberia has been smothered by atypically warm temperatures for nearly six straight months. Some years will inevitably be cooler, which may mean less favorable conditions for flames.

There's a diversity of ecosystems burning in the Arctic right now, according to an analysis by Smith, including forested areas, shrublands, and tundra. Importantly, the ground in some of these burning areas is peat (though it's hard to precisely estimate how much), which means old, thick deposits of carbon are burning and releasing the potent greenhouse gases carbon dioxide and methane into the air.

Quote
An important takeaway from the last two extreme years of Arctic blazes isn't that there's bound to be such intense fire seasons each summer now, but that ever-warming environmental conditions allow for such atypical burning to be possible, or increasingly possible. "We don't expect these fires all the time," said McCarty. "But we know the landscape can burn."

During the spring, some of 2020's Arctic fires may have been zombie fires, or holdover fires, which survive underground during the winter and then reemerge the following year. But overall, some 85 to 95 percent of fires are ignited by humans, either intentionally or accidentally, explained McCarty. Yet lightning strikes often start the biggest Arctic fires, she said, and as the region incessantly warms and the air becomes more humid in the summer, this polar region could see more lightning.

"In the future, we expect more lightning strikes in the Arctic in a warmer climate — thus more potential for Arctic fires," said McCarty.

There will be more burning in the Arctic Circle this summer, as a stagnant, warm weather pattern continues to heat the region. And as with any heat wave today, particularly in the fast-changing Arctic, hot weather patterns are amplified by climate change. This means heat events today are warmer than they would have been without human-caused global warming.

Under these hot and dry conditions, Siberia is an expansive land that's primed to burn. "You’ve got so much dried-out material," said Smith. "It can burn, and burn, and burn."

43
Arctic sea ice / Re: The 2020 melting season
« on: June 27, 2020, 01:03:34 AM »
Is it just me or has it been sweltering in the CAA?? I hate to rely on models so much, however the temperatures as indicated on windy.com have had several of the larger islands in the 50-60f range. I can't say I doubt it that much given the blue hue of the ice, but this entire season is just so strange and lot like the others in my opinion.
r
No need to doubt, the CAA has quite a few weather stations and you can view daily and even hourly temperatures online. Here's a map showing these weather stations and the max temps (C, not F) for June 26th. Sweltering indeed.

44
Arctic sea ice / Re: HYCOM vs ASMR2 Imagery
« on: June 26, 2020, 10:46:25 PM »
Wht not compare Hycom to the Cryosat +SMOS thickness map from April 15th? That map should be quite reliable. This way you can see if Hycom is in the right ballpark, at least for that date before melting begins.

45
Arctic sea ice / Re: The 2020 melting season
« on: June 26, 2020, 03:31:13 PM »
The CAA channels have not been moving, and Hycom is not good with this sort of thing.

46
Consequences / Re: COVID-19
« on: June 26, 2020, 11:28:39 AM »
With 0.25% apparent IFR (assuming no one died at home), it seems Ischgl got it lightly (even considering its young population), and is near to herd immunity in the process. In any case, the numbers are low, but not out of the ballpark.

47
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: June 26, 2020, 11:20:36 AM »
Yes, the wind is holding the whole house of cards in place.

48
Permafrost / Re: Arctic wildfires and their effect on sea ice
« on: June 26, 2020, 08:55:19 AM »
So, is there a trend in Arctic wildfires? Are fires in Siberia indeed increasing in extent? Are they showing up earlier, thus increasing compared to the date? Some data would be helpful in assessing the risk. Saying it will increase from say 1000 to tens of thousands is concerning, but with no data to back this up the discussion is less effective.

49
Arctic sea ice / Re: HYCOM vs ASMR2 Imagery
« on: June 26, 2020, 08:49:01 AM »
I don't tend to rely much on Hycom, I doubt its veracity, but that's just my intuition as I've never done a rigorous verification.

50
Arctic sea ice / Re: The 2020 melting season
« on: June 25, 2020, 11:42:56 PM »
Hi Folks, 
  Complete newbie here, but I've been lurking for a while.  Just a quick question if I might:  why is it that the ice is thickest immediately north of the CAA?  Has this always been the case or is it a recent development?  Thanks!
Welcome KenB. This fits better in the questions thread but the basic answer is yes, it's "always" been the case, there is a general drift from the direction of Siberia towards CAA/Greenland. Watch this video to get the hang of things.

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