Messages

1

The forum / Re: Forum Decorum

« on: September 26, 2020, 05:52:45 PM »

Well that is off topic there since whatever you or A believe is not that important in the grand scheme.
Basically it´s for relevant Tesla news and not all that is posted is that but if it offends you then just skip the thread.

if belief were entirely out of threads then it would be more important to police what threads can be started since belief would be expressed there, as you know this is not the case because knowledge is partial and interpreted both here and more generally, so I don’t think what you described is off topic, unless, of course, only your interpretation of knowledge is the right one

2

Arctic sea ice / Re: Melt Ponds

« on: September 05, 2020, 01:43:45 AM »

The bulk of ice forms with vertical growing ice crystals this plus the exclusion of salt tends to create channels through the ice. If the ice is thicker than 2 meters it is likely stacked but that process has some gaps between layers. The freeze melt cycle will over seasons fill these channels. Freshwater ice is more solid and would not have channels to drain through.

freshwater ice most definitely can be porous and saturated with water, whether waterfall or glacier ice

3

Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask

« on: August 23, 2020, 06:20:59 PM »

what does fractional ice mean?

Wrong question if this https://forum.arctic-sea-ice.net/index.php/topic,2906.msg282135.html#msg282135 contains the answer.

No such thing as a wrong question, it’s in the title of the thread, but the link you gave is mostly what I was looking for, however I am now curious on how the solid layering represented by the ice makes the fractional boe properties differ from an actual boe and whether it should, thereafter, be considered differently, probably a discussion more appropriate in another thread

4

Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask

« on: August 23, 2020, 04:18:40 PM »

what does fractional ice mean?

5

Arctic background / Re: Russian Arctic Exploration

« on: August 23, 2020, 05:19:17 AM »

A video on the first nuclear icebreaker

6

Arctic sea ice / Re: The 2020 melting season

« on: August 22, 2020, 09:38:13 PM »

Another element that this August weather has brought is significant cloudiness especially in the pacific half, which means heat excess retention and enhanced melting.
I’d be surprised if Arctic temperatures in August are not well above average.

You've looked at air temperatures just above the ice? This is either not accurate or a very small effect given the positive temperatures being concentrated on the Svalbard side and the negative ones on the Alaskan side

Air temperature just above ice is capped at the melting point of that ice and won't tell you anything about excess heat retention nor enhanced melting.  Looking at temperatures in the arctic that are not above the ice will give you some idea whether or not Arctic temperatures in August are well above average.

It is not good in general, however in the specific context, the differential is ample enough to show that the cloudiness in Beaufort/ Chucki didn't lead to higher temperatures/ temperatures retention as claimed by Gandul compared to the rest of the basin, which doesn't mean that temperatures are not above average

7

Arctic sea ice / Re: The 2020 melting season

« on: August 22, 2020, 03:52:00 PM »

Another element that this August weather has brought is significant cloudiness especially in the pacific half, which means heat excess retention and enhanced melting.
I’d be surprised if Arctic temperatures in August are not well above average.

You've looked at air temperatures just above the ice? This is either not accurate or a very small effect given the positive temperatures being concentrated on the Svalbard side and the negative ones on the Alaskan side

8

Arctic sea ice / Re: The 2020 melting season

« on: August 21, 2020, 10:46:34 PM »

A very important observation!
IMHO
The major metrics that are currently referenced during this stage of the 2020 melt season VOLUME. AREA and EXTENT may serve little useful purpose; the exceptions are compaction, weather and observations.

In particular, wrt the posting by Bremer, the presumption that the BOE will be a September minima must be challenged. Indeed, October or even November must now be given serious consideration and should this prove to be the actuality the implications for both summer and winter sea ice will be very significant.

+1 for thinking outside of the box

I would challenge this notion in the current arctic, given that darkness sets in above 80N and the smallness of the area of the arctic sea ice, especially outside 80N, in late September, it seems very unlikely that even strong SSTs could delay area gains more than a week at most, let alone continue the thaw. It would be interesting with column mixing, but given the low winter temperatures it would still not amount to much, especially if we are talking about continued thaw, although it could have effects on reduced thickness increase and delayed freezing. Now the Laptev and the ESS are where it’s at, heated at depth, mostly below 80N, but they don’t play a role in a boe or the cutoff between the freezing and thawing season anymore

9

The rest / Re: forums

« on: August 20, 2020, 09:41:16 PM »

What are other forums you know, especially those similar to asif on their scientific focus?

I'm not biting this one, sorry, a dangerous topic, full of holes to fall into, good luck.

Just wanted to say this first instead of sounding smartassy after 

Fair enough, but why?

10

The rest / forums

« on: August 20, 2020, 03:47:49 PM »

What are other forums you know, especially those similar to asif on their scientific focus?

11

Arctic sea ice / Re: The 2020 melting season

« on: August 19, 2020, 09:37:16 PM »

PIOMAS gridded thickness data was updated to day 228 (15/16 August). Calculated volume on that day is 5.14 [1000km³], which means a third lowest place before 2012 and 2019.

Here is the animation for August thus far.

Quite a bit of that ice isn't there anymore, it also accounts for a lot of the weaker thinner ice glennbuck mentioned, so will we be able to trust piomas at minimum? Further if melts happen beyond normal parameters I think we can see how piomas model is like when stretched beyond its capabilities

12

Arctic sea ice / Re: The 2020 melting season

« on: August 19, 2020, 09:33:22 PM »

Yes very warm surface air temps for this time of year in the Arctic Ocean. 2016 surface air temp today vs 2020, 2018 and 2014. Surface Air Temp in green circle. That area is 4C - 6C for the next 5 days.

2014    0.1 C 
2016    0.9 C
2018    2.1 C
2020    6.0 C

Warmer than earlier years, sure, but there's no ice where your circle is. In general even in 2020 there are no areas with ice above freezing except a few areas off the Canadian Arctic Coast. This might slow refreezing in the fall, but record heat notwithstanding, top melt is still basically done.

Not according to the gfs 2m temperature forecast where half the arctic basin is consistently above 0 an there are not many areas wit temperatures below sea water freezing point, note that the areas above 0 change wildly too, leaving the whole basin to at least still get a taste of it
https://sites.google.com/site/arcticseaicegraphs/forecasts

13

Consequences / Re: COVID-19

« on: August 18, 2020, 08:49:51 PM »

The CFR is a terribly misleading indicator. The IFR seems to vary with time and location, several sources place it around 1% for the first wave in mid latitude occidental countries but much lower in countries like India; race, eating habits, vitamin D levels, age distribution and others playing a big role. The IFR goes down as hospital treatment improves too. The IFR is something more related to reality of the illness than the CFR which means nothing to be honest.

CFR is not misleading whatsoever.

...

IFR remains a speculation.  One cannot indicate any number with IFR as we have no reliable way to measure this variable.  The 1% figures are not reliable, nor are the 0.1% figures - without accurate instruments, this is merely speculation.

The only accurate information we have regarding the coronavirus is CFR, from reliable goverments.  For example:  France, Italy, UK, Germany, and prior-to the Trump data massage, the US.

As long as we focus on the available data from reliable governments, we can make a measured conclusion:  This coronavirus is extremely serious.

Let’s agree that the numerator “fatalities” is the same in both cases.

The denominator of IFR is infections, period. If you have a scientific method to infer infections among the population, you have an estimate of IFR.

The denominator of CFR “Cases” can be
- Grossly reduced if the illness is asymptomatic or mild for a significant percentage of infected population that will never become cases.
- Grossly reduced by reducing active testing on purpose (a la Trump)
- Grossly reduced when the wave is peaking, health system is overwhelmed, and only a fraction is tested (happened in Europe almost everywhere at some point).
- Reduced by uninsured people not willing to go to the doctor (an issue in the US mostly and other 3rd world countries)

So WHAT THE HELL ARE YOU TALKING ABOUT HARPY?

the death side of the equation can also be underestimate particularly in countries like India where many deaths are just not counted and do not pass through a centralized funerarium system, or Russia where the criterias to consider a death cover related are extremely restrictive.
Further there is delay between infection and death which can further skew things towards an underestimation of the ifr

14

The forum / Re: Forum Decorum

« on: August 18, 2020, 07:40:56 PM »

Looks like it.

Lovely community vibe here.

We lost a valuable member today

15

The forum / Re: Forum Decorum

« on: August 18, 2020, 07:39:30 PM »

anyways this is the last pm I tried to send him, unfortunately too late, hopefully he will read it, his part redacted for privacy, for context I approached him a couple of hours ago to suggest just blocking pms.

I don't think Oren is doing this on a personal basis, more because of the general amount of bottom notifications this drama created, maybe you should take it up to Neven directly on the matter of your mod retirement with, for example, screenshot proof of your innocence. He is stubborn though so he may not even acknowledge he was wrong. In which case start a different forum thread, so at least it's not pinned to the top and can subside once everything is settled.

[redacted blumenkraft pm for privacy]

I didn't mean take screenshots of him, rather screenshots of your pms showing the absence of conspiracy, but whatever I get why you're uneasy but if you want (if you don't that's fine too) Neven to recognize he was wrong, private messages are a lot better than a public forum where he has acumen and open backing, which never go well with revising your positions. (I don't know what NT means btw)

The harassment was noticeable, even in public, and I don't get why the other mods didn't stick by you more, hopefully it at least gets better now. I am sorry you experienced this, and please remain an Asif member

Not everyone thinks you're an asshole, most people will not even read the thread (thank god), and distanciation should do the trick of him not going after you. However it is not the first time something happened with [redacted for drama avoidance], and that kind of pattern needs to be regulated, which is what I alluded to both in my comments and here. I know you're not a mod anymore, but if it repeats itself again (happened on the cryosphere before) we really need to talk to Neven, because it's not going to get better.

Hoping you're doing better,
regards

PS: I relent any privacy privilege from this conversation so feel free to quote whatever you want, with no incidence on the privacy of your messages of course.

16

The forum / Re: Forum Decorum

« on: August 18, 2020, 07:25:30 PM »

did Blumenkraft just quit?

17

The forum / Re: Forum Decorum

« on: August 18, 2020, 05:44:13 PM »

Freegrass, I didn't say that

18

The forum / Re: Forum Decorum

« on: August 18, 2020, 04:54:56 PM »

when I said self restraint by EVERYONE, I wasn’t kidding, that includes you Neven, as the admin, sure you’re fallible, like all of us, however remember this is a public forum and how you are portraying yourself, would you be proud if a family member saw what you just said? or prominent members of your community for that matter? To reflect poorly on yourself and diminish your office is something beyond a thing you can just not care about, this is shallow and deep down you know you care, we all care, like when other things happened in this forum. Please consider using a tone and content appropriate for your position, it is not just because of trust from the asif members but because you will regret your newfound public persona because of private beef, should I remind this is how future generations will remember you? They may even take cyber museum tours of the forum, given the topic, so rise to the moment and self moderate, everything you say is here forever, it’s the internet after all.

To Freegrass, I don’t think anyone is gaslighting you, if they are, sure that would be bad and shouldn’t be allowed on the forum, otherwise please seek help like talking to closed ones about how you feel or professionals, I have family who has similar thoughts, unsubstantiated, and it gets sour for everyone and alienates you.

To Kessy, hope this was an I am sorry you feel this way comment, I am optimistic so I will say it is, not an arrogant/sarcastic one

19

Policy and solutions / Re: Lessons from COVID-19

« on: August 18, 2020, 11:24:20 AM »

It's not just the masks, but also this idea that the enemy is everywhere around you (which to me is Al Qaeda on steroids) and that the only way to fight this enemy is through mandatory vaccinations, vaccination passports, tracking apps etc. And that anyone who doesn't support this, is an insensitive, dumb person.

One of these days I will try to convey how I would like the presentation to shift (by media and politicians), and make an effort to evade polarizing pitfalls.

The problem is the hoarding of power by governments, it is sensible to have temporary measures in the face of unexpected catastrophe but there needs to be institutional resilience to revert back to normal once it’s over. New Zealand is probably the best example of that, while China is almost the opposite, using routine powers (to them) to impose strict measures

20

The forum / Re: Forum Decorum

« on: August 18, 2020, 11:12:37 AM »

(When I recreated my account 2 days ago, I did it with the intention of explaining more thoroughly my reason for leaving this site. The comment did not pass moderation and I am fine with that. Below is a condensed version.)

1. I was attracted to this site in 2013 by its grounding in science.
2. I am dismayed by persons on this thread for whom I had developed a great deal of respect who have abandoned all science in arguing how inconsequential this disease is.
3. This has caused me to question in a very personal way why I come here.

I hope this comment passes muster.


<I think you are wrong on count 2. Neven chose a category in his description. The actual detail was not really important because it was more about the media in general. One problem is that we make a division when someone foregrounds an issue and then people focus on the less important part as intended by the poster.

If we would all be on voice comms you can ask quick questions to clarify. Here we can´t but we can ask slow questions before jumping to conclusions.

This is a general point not for SH per se.
kassy>

Thank you Kassy for allowing this comment to post.

As for point 2, I am dismayed.

I did not single out Neven and, if I had the time or inclination, (I don't) I could go back into this thread and find numerous persons who have dismissed the data and argued for a ridiculously low IFR and dismissed the science that points to serious health problems for many who recover from the virus, the kinds of health problems you never find from persons who have recovered from the flu.

At any rate, the three numbered points above stand. They accurately and succinctly summarize exactly where I am. While I suspect this is my last comment on this site, I will not hastily delete the account this time. This will allow me to reconsider this decision in the future.

Everyone - Take care and stay safe.


<Another general comment: The main interest for this site is the Arctic ice. You can ignore huge parts of this site and still do things. Or even read AGWiG/C and just ignore covid. kassy>

To me this is clear overreach, being a mod doesn’t allow to hijack good faith level headed comments because they disagree with another mod edit, Oren, which I would consider the gold standard in snipping and editing, only use this to correct behaviour that is moddable and to explain the etiquette for modding not to happen again, whereas this doesn’t qualify to a reasonable criteria and advance the mod interest rather than the community, albeit most likely not on purpose.

I think it is a shame Blumenkraft quit modding, and given the circumstances it happened in, may I suggest for EVERYONE to exercise self restraint, even admins, and also keep in mind more generally that your info might be false or supplied by people who can be intoxicated, mentally unwell or otherwise partial sources, which should be welcomed with open arms on the forum but engaged in a constructive way that doesn’t lend too much credence to hearsay and try to stave off any episode and not play into it.


I am now for guidelines because the complexification of social relationships, especially on non cryoshpere threads, necessitates them for the mods to do a clean job, though I might be biased coming from a civil law nation. This should include safeguarding guidelines on mental health and inclusivity. the mods are not at fault, it is just the natural course of a mini human society.

21

Arctic sea ice / Re: The 2020 melting season

« on: August 18, 2020, 07:40:00 AM »

Another HYCOM prediction. Looks like thicker ice is going to vacation to Beaufort Sea 

Pretty interesting that it predicts both the kara and the greenland sea ice to go poof, although it will be almost certainly untrue for the latter with gusts of over 100 km/h from the 24th turbo driving exports, I think it is missing on the Beaufort disintegration though, it’s looking as ready as the greenland sea ice in places I would say

22

Arctic sea ice / Re: The 2020 melting season

« on: August 08, 2020, 04:23:03 PM »

a Bremen graph that I do not see often and that they don’t seem to publish often

23

The forum / Re: Arctic Sea Ice Forum Humor

« on: August 08, 2020, 04:15:50 PM »

The ice inn

I’d love to pay a visit while we still can

24

Arctic sea ice / Re: Meaningful artifacts in the Arctic data and their underlying causes

« on: August 06, 2020, 02:38:18 PM »

Another day, another anomaly.
I used to post Bremen graphs periodically but recently stopped due to this anomaly.
Bremen amsr2 often disagrees with jaxa and nsidc, because of its higher res, however the departure is now substantial, especially in terms of trends. While extent in low res has kept apace, and area was seeming to pick during the latest gerontocrat update, in high res they have both brutally slowed down.
This seems highly unusual especially with the Beaufort wrecking, and might be a result of cloudiness, either an underestimate during the gaac or an overestimate now, with the sensors recalibrated during the gaac. given how sensible it is to clouds I consider amsr2 more suspect but given the difference and divergence, either 1st or 3rd and already seeming to wrap up the season, it needs to be resolved beyond assumptions.

25

Arctic sea ice / Re: The 2020 melting season

« on: August 05, 2020, 02:26:45 PM »

Are there any opinions on the value and accuracy of the various arctic 10 day forecast animations at weather-forecast.com?  I like the visuals and options but am wondering about the predictive value?

I said before, in another thread, that it cannot be trusted, it is utterly useless, was predicting lows during the long basin wide highs, and routinely predicts patterns contrary and opposite to the main models. If you want to use a weather forecast, here’s good
https://sites.google.com/site/arcticseaicegraphs/forecasts

26

Arctic sea ice / Re: The 2020 melting season

« on: August 03, 2020, 04:08:54 PM »

it seems that I was wrong about continued cab loss, we have had a continuous slow down instead, this must be because of thicker ice because top melt is continuing apace with an unusual continual pulse of warmth along the greenland to laptev cab, already present several days ago, with melt not stopping even at the north pole within 10 days apart from an ess island as well as the laptev edge, although the latter only in the unreliable part of the forecast. Furthermore the euro model seems to start to indicate a high pressure in the beaufort, where insolation is higher due to its lower latitude, this combined with the surface temperature forecast showing some waa towards the thicker parts of the beaufort, means that along with bottom melt, which will be increased after more insolation given the latitude, the ice will keep being attacked from the top. Given the known melt ratios of the beaufort, it is probable most of it will melt out before refreeze, although it might take some time (highest bottom melt in the end of August)(https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2008GL034007). This is even more apparent given the destruction made by the cyclone, as can be seen in the subsequent bremen maps, and should be fully revealed within a week as high pressure takes hold in that region.
The previously mentioned cooling, appearing in the front that was most active (ess, laptev) seems shallow, limited to the ice margins, which means that any plateau or continuous slow down in area or extent  would only mask the thickness loss, which should already become clear with the piomas update due very soon. This masking effect should also stop soon in the caa, where thickness, according to hycom, is deadly low.
Winter is coming, but not before Rome burns.

https://sites.google.com/site/arcticseaicegraphs/forecasts?overridemobile=true

27

Arctic sea ice / Re: Freeform season chatter and light commentary

« on: July 30, 2020, 06:10:27 PM »

https://www.weather-forecast.com/maps/Arctic
I don't know what model this forecast runs on but it is bad, don't use it

28

Arctic sea ice / Re: The 2020 melting season

« on: July 30, 2020, 05:48:17 PM »

I think given that the boundaries still have high pressure (chuchki and eastern cab), that there will be some rain in the low pressures, that the temperatures at the surface are globally still positive and therefore conducing to top melt, especially with the waa north of Greenland and Fram, with continued pronounced positive temperature anomalies in the Siberia to Greenland front, all for the next five days at least, it is not unreasonable to predict that the cab area nosedive will probably continue at the present pace (50 k) for at least a week, putting us in a very good position to beat the record low and affecting both concentration and ice pack integrity (compaction is already back to very low levels), and probably the piomas numbers too as they take the area numbers into account. The run to the pole before refreeze is on

29

Arctic sea ice / Re: The 2020 melting season

« on: July 30, 2020, 05:38:59 PM »

Comparing the last 2 days of AMSR2 sea ice concentrations, we can already see the start of a correction in the Central Arctic and southwestern Beaufort.

I suspect we will continue to see corrections from sensor errors, that are currently showing faux reductions of sea ice concentrations. This will be obvious in the Central Arctic and Beaufort over the next several days.

It is not faux reduction, it is a known effect subsequent to meltponding, similarly the concentration is artificially inflated where the low is compared to reality due to clouds, sensor error makes it seem like a one time thing, which is being adjusted back, it is only the long acknowledged response to certain phenomenons.
Edit added high res amsr2 on the Beaufort you can see the preliminary results of the storm and I think even the clouds that blocked concentration in the real colour image

30

Arctic sea ice / Re: The 2020 melting season

« on: July 29, 2020, 10:14:11 PM »

JAXA arctic sea ice volume

isn't that near boe values for volume (1000 km*km*km)?
does anyone explain the discrepancy with piomas, is it just regular model differences or is there something I am missing?
Anyways I hope this quiets the choirs expecting a relatively muted end of season, when we're first everywhere with incredible preconditioning and almost the worst possible scenario in weather, I really don't see any evidence pointing in the other direction. Hopefully we'll still miss the mark of my prediction down below.

31

Arctic sea ice / Re: 2020 Melting Season Predictions

« on: July 28, 2020, 12:00:38 PM »

weatherdude88 prediction

JAXA and Uni Hamburg data show 2020 as compact, as the most compact years in the data set. NSIDC compactness has moved towards the middle of the pact.



I would be surprised if NSIDC extent finishes in the top 4 this year.

High resolution sea ice extent may no longer be the lowest in the data set within 1-day.



<Removed goading and unnecessary quotes. Focus on data please. O>

32

Arctic sea ice / Re: Meaningful artifacts in the Arctic data and their underlying causes

« on: July 27, 2020, 09:29:59 AM »

Gif courtesy of Unicorn, at the end you can the ce close to the northern Greenland coast going north while the one farther away seems to go south. Could that be an eddy or contradictory winds pushing down ice from the southern CAB and north ice from the Greenland coast?

https://forum.arctic-sea-ice.net/index.php?action=dlattach;topic=3017.0;attach=277528;image

33

Arctic sea ice / Re: Contrails and Aerosols effects on the melt season

« on: July 25, 2020, 05:13:56 PM »

el cid, look at the study, they have divergent findings from that. Besides the other source that the reduction of primary aerosols didn't necessarily mean a net reduction in aerosol because of the increase of secondary product aerosols

34

Arctic sea ice / Re: Contrails and Aerosols effects on the melt season

« on: July 25, 2020, 11:20:49 AM »

el cid, the fact that china was not lockeddown at the same time is major, and several countries only locked down in april-may (south america), very little or not at all (the US), and as I said there would be a delay anyways due to the time it takes for aerosols to degrade.
that’s even more damning

Comparisons among the simulations altering emissions, chemistry, and meteorology reveal that the unprecedented NOx reduction during the COVID 19 does not significantly reduce aerosol formation because of the non-linear ozone and aerosol chemistry

https://science.sciencemag.org/content/early/2020/06/16/science.abb7431

for production I meant compared to the overall gdp loss and on a yearly basis, because aerosols take time to degrade (3 months https://pubs.acs.org/doi/10.1021/acs.est.6b02313# )

yeah environmental law relaxation happened, and look at the date https://www.google.com/amp/s/mobile.reuters.com/article/amp/idUSKBN20X0AG
https://www.google.com/amp/s/www.bloomberg.com/amp/news/articles/2020-03-18/china-may-help-struggling-carmakers-by-relaxing-emission-curbs

All in all, it is logical that the aerosol reduction has not been strongly felt globally temperature wise

35

Arctic sea ice / Re: Contrails and Aerosols effects on the melt season

« on: July 25, 2020, 09:28:38 AM »

I took a look at 2020 monthly temperature anomalies vs 2015-19 average at GISS Temp.

here are the results :
Jan +0,21 C
Feb +0,19 C
Mar +0,07 C
Apr +0,20 C
May +0,17 C
Jun +0,13 C

We had an "amazing", unprecedented and likely unreplicable experiment this year when globally many many factories closed off, airplanes were grounded, cars stoped, etc from roughly mid-march to mid-May, so aerosol emission fell by a lot.

If there were a big aerosol effect then April (and partly March and May) temperatures should have been much higher than  Jan, Feb and June. They are not. And this somewhat proves to me that aerosol effects are not as strong as estimated.

For one aerosol reduction as already been studied, notably the difference after air pollution measures,
and more importantly the covid is not a good event to study aerosol reduction, it has had countries opening and closing at different times, production didn’t take that huge a hit where it matters, and environmental laws were relaxed, compensating aerosol reduction. Besides they take several weeks to decompose, so they might have stayed long enough to be replaced.

36

Arctic sea ice / Re: The science of ice ridging and rafting

« on: July 24, 2020, 07:20:48 PM »

(sure Tor and how old was it?) (edit: next time don’t bury the lead) plus keep in mind the general loss of thick ice in the last few years.

Your experiment is flowed because it doesn’t have the same variables, plus it isn’t even what you originally said. What I quoted is from an engineering perspective so I do think they would have accounted for other forces if there were, anyways show just one source that says it isn’t true or become one (preferably get published) then you can refute the point several sources made.
If you want to pursue the experiment keep in mind that in reality the ice is not much cooler than its environment as opposed to your experiment, plus mechanical movement means the temperature needs to be actually lower than freezing point, of course salt the water.

37

Arctic sea ice / Re: The 2020 melting season

« on: July 24, 2020, 06:30:58 PM »

maybe due to continued area losses?

38

Arctic sea ice / Re: The science of ice ridging and rafting

« on: July 24, 2020, 05:52:05 PM »

Tor, respectfully you didn't understand it, it is a below freezing air requirement, because otherwise no ice to serve as glue. Also I think you are making an hyperbole in how thick how quickly the ice can get because the biggest floe ever recorded was 45 meters thick and 100 years.

39

Arctic sea ice / Re: Contrails and Aerosols effects on the melt season

« on: July 24, 2020, 11:35:14 AM »

are those ground temps or air temps? because aerosol reduction increase the earlier and decrease the latter, which is logical, there is no additional insolation from the sun, it is just no longer stopped in the atmosphere

40

Arctic sea ice / Re: Crowdsourced facts on sea ice for newcomers and people wanting to learn more

« on: July 24, 2020, 10:33:43 AM »

agreed, there is only a couple subjects I can even touch on, I will message some of the more knowledgeable posters to see if they are interested in contributing

41

Arctic sea ice / Re: The science of ice ridging and rafting

« on: July 24, 2020, 08:15:12 AM »

michael yes it says it needs below sea ice freezing air, it considers ridge formation only when there is a combination of block that get glued together by new ice, while consolidation happens in summer when the ice gets less salty and smoother from melt. It technically depends on what you consider ridging but to only consider whether there is rubble makes it a shallow definition, ridging being a source of ice thickening, which can only be true with the mechanism described above. Also you have provided no counter info on ridge formation, or had anything that would have indicated the processes described were only typical, and the source is categorical itself, nit making exceptions or qualifying the processes described as solely typical

42

Arctic sea ice / Re: Crowdsourced facts on sea ice for newcomers and people wanting to learn more

« on: July 23, 2020, 11:53:10 PM »

effects of arctic sea ice changes

43

Arctic sea ice / Re: Crowdsourced facts on sea ice for newcomers and people wanting to learn more

« on: July 23, 2020, 11:39:05 PM »

geographical and local effects on the sea ice

Fast ice

islands

Canadian Archipelago

44

Arctic sea ice / Re: Crowdsourced facts on sea ice for newcomers and people wanting to learn more

« on: July 23, 2020, 11:36:07 PM »

Feedback loops and climate change related to the sea ice

CLIMATE CHANGE

permafrost loss

early river ice break up

FEEDBACK MECHANISMS

Albedo loss

moisture from melt


(image credit to Gerontocrat)

45

Arctic sea ice / Re: Crowdsourced facts on sea ice for newcomers and people wanting to learn more

« on: July 23, 2020, 11:35:31 PM »

arctic water currents, bathymetry, water layers and other oceanic related things

WATER CONDITIONS

SSTs

layering

bathymetry

Atlantification and pacification

WATER MOVEMENTS

arctic currents

gulf stream and related

waves

tides

water mixing

46

Arctic sea ice / Re: Crowdsourced facts on sea ice for newcomers and people wanting to learn more

« on: July 23, 2020, 11:34:35 PM »

arctic weather and atmospheric patterns


ATMOSPHERIC PATTERNS

jet stream

arctic oscillation


WEATHER PATTERNS

pressure ridges

highs pressures

low pressures

dipoles

cloud cover

precipitations

winds

47

Arctic sea ice / Re: Crowdsourced facts on sea ice for newcomers and people wanting to learn more

« on: July 23, 2020, 11:34:07 PM »

mechanisms for ice growth (ridging, physics...)

Ridging, rafting and rubble

Snow cover

physics

sea ice stages

multi year ice

landfast and bottom fast ice

48

Arctic sea ice / Re: Crowdsourced facts on sea ice for newcomers and people wanting to learn more

« on: July 23, 2020, 11:32:35 PM »

Mechanisms for ice melt and loss (insolation, temperature, dispersion, physics...)

MELT

Bottom melt

insolation and Albedo

melt pond

temperature

side melt

mechanical melt and melt physics

EXPORT

dispersion

Fram and Nares

sea ice circuit

garlic press

49

Arctic sea ice / Re: The science of ice ridging and rafting

« on: July 23, 2020, 11:25:57 PM »

the formation of the sea ice ridges, they require freezing (-1.8 ) air temperatures to form.
https://www.eolss.net/Sample-Chapters/C05/E6-178-66.pdf

The initial phase starts during ridge formation and is characterized by the formation of
freeze-bonds. Three different heat fluxes are important: a) the surface flux ( qsur ), into the cold surrounding air, b) the oceanic flux ( qocean ), from the ocean beneath and c) the
internal fluxes ( qre ), in between the cold pieces of ice and the warm water pockets
inside the keel (Figure 3). The surface flux freezes the water pockets from the top and downwards and creates a cold front that defines the consolidated layer. The initial cold content of the ice is partly spent in making freeze bonds and partly consumed by the oceanic flux. The fraction that goes into making freeze bonds depends on the initial ice temperatures, the block thicknesses, the ridge size and the oceanic conditions. When all the ice and water below the cold front is isothermal that is at the freezing point of the surrounding water the initial phase ends.
The rubble beneath the consolidated layer is thermally insulated by the freezing front on top of it, and feels only the water below. Since the conditions are isothermal there is no longer any cold reserve available and the rubble decays continuously. The rubble transforms from individual ice blocks with freeze bonds to an ice skeleton with a hierarchy of pores, from a few centimeters and up to meter(s).
In the decay phase the ridge is heated both from the top and from the bottom. The ridge now either melts completely, or it transforms into a second-year ridge during the summer. Several processes take place. On the surface the warm air and the sun radiation melts the snow and the surface ice and creates relatively fresh melt-water. Its freezing point is above the temperature in the rubble so it will freeze as it drizzles down in the keel. This freezing process release heat and increases the temperatures in the rubble. In this way the decay phase includes both melting and freezing. Freezing can take place as long as there is cold capacity (ice temperature less than the freezing point of the melt water) in the keel. However, another mechanism can contribute to further consolidation. If the pore water salinity is changed cyclically, either by periodic surface melting or by tidally driven river runoff the ridge could actually expel heat into the surrounding water
and contribute to further freezing (consolidation). This mechanism is only shown in laboratory investigations and in simulations. Finally the ridge keel could collapse and in this way decrease the porosity and increase the degree of consolidation. By the end of the melt season the ridge has become a second-year ridge.

50

Arctic sea ice / Re: What's new in the Arctic ?

« on: July 23, 2020, 10:42:27 AM »

the formation of the sea ice ridges, they require freezing (-1.8 ) air temperatures to form.
https://www.eolss.net/Sample-Chapters/C05/E6-178-66.pdf

The initial phase starts during ridge formation and is characterized by the formation of
freeze-bonds. Three different heat fluxes are important: a) the surface flux ( qsur ), into the cold surrounding air, b) the oceanic flux ( qocean ), from the ocean beneath and c) the
internal fluxes ( qre ), in between the cold pieces of ice and the warm water pockets
inside the keel (Figure 3). The surface flux freezes the water pockets from the top and downwards and creates a cold front that defines the consolidated layer. The initial cold content of the ice is partly spent in making freeze bonds and partly consumed by the oceanic flux. The fraction that goes into making freeze bonds depends on the initial ice temperatures, the block thicknesses, the ridge size and the oceanic conditions. When all the ice and water below the cold front is isothermal that is at the freezing point of the surrounding water the initial phase ends.
The rubble beneath the consolidated layer is thermally insulated by the freezing front on top of it, and feels only the water below. Since the conditions are isothermal there is no longer any cold reserve available and the rubble decays continuously. The rubble transforms from individual ice blocks with freeze bonds to an ice skeleton with a hierarchy of pores, from a few centimeters and up to meter(s).
In the decay phase the ridge is heated both from the top and from the bottom. The ridge now either melts completely, or it transforms into a second-year ridge during the summer. Several processes take place. On the surface the warm air and the sun radiation melts the snow and the surface ice and creates relatively fresh melt-water. Its freezing point is above the temperature in the rubble so it will freeze as it drizzles down in the keel. This freezing process release heat and increases the temperatures in the rubble. In this way the decay phase includes both melting and freezing. Freezing can take place as long as there is cold capacity (ice temperature less than the freezing point of the melt water) in the keel. However, another mechanism can contribute to further consolidation. If the pore water salinity is changed cyclically, either by periodic surface melting or by tidally driven river runoff the ridge could actually expel heat into the surrounding water
and contribute to further freezing (consolidation). This mechanism is only shown in laboratory investigations and in simulations. Finally the ridge keel could collapse and in this way decrease the porosity and increase the degree of consolidation. By the end of the melt season the ridge has become a second-year ridge.