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Messages - binntho

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1
Arctic sea ice / Re: Arctic energy balance
« on: Today at 07:13:09 AM »
Tables are convenient. One last thing is wind front. 5 m = 0.005 km. And we have 0.1% in result.

10-14 kg/m2 of water vapor is a high number for the Arctic. May begins with below 5 kg/m3 usually.

Considering thicker layer, strong WAA contains enough energy to melt 200 km3/day. It does not mean that only the WAA did 200 km3 per day. But there is a way to transfer significant part of this energy to make the ice darker and more vulnerable for visible light. Combined effect of the WAA and clear sky seems to explain extreme melting that day.

Having said that, I am pretty sure that radiative thermal transfer of air only starts to become significant in comparison to conduction at much higher temperatures than are found in the atmosphere.
looking at the main image here, conduction is actually negligible compared to radiation.

I can see that you found the error that I feared in my dreams!

The only real contention in all of this is the thickness of the air used in the calculation, and that in the end rests on the relative effects of conduction vs. radiation.

At "weather" temperatures, radiation is truly a wimp when it comes to transferring heat. You can test this on your self - you do not feel heat radiating from a window even if it's freezing inside and 20 degrees outside. But you feel the temperature of the air as soon as you touch it.

You do not feel the heat of thermal radiation from a hot tub of water - but you do feel the heat of the steam settling on your skin. You do start to feel the heat of radiation from the sides of a freshly boiled kettle, but still not enough for you to stop touching it by mistake and then fealing the real heat transfer of conduction.

So if you think that thermal radiation from a 15 degree C body of air in one day is enough to melt any ice at all, let alone any significant amount, then please show some evidence!

2
Arctic sea ice / Re: Arctic energy balance
« on: June 02, 2020, 03:47:13 PM »
Do you not understand that heat is thermal radiation?

No, heat is not thermal radiation. Your question shows a lack of undersanding of thermodynamics. But I must admit that I have been using the word "heat" with lack of precision.

So let us split it into more formal categories / definitions:

1) Heat transfer is the transfer of energy from one system to another. There are basically two methods of transferring thermal energy, radiative transfer and conduction (some Americans add friction as a method of transferring heat, but that's of no consequence).

Radiative transfer of energy is how the sun warms the earth (and our skin when we are out in the sun). Conduction is how air (and water) primarily transfer heat internally and to other bodies, although some radiative transfer is always ongoing (and grows with added energy, but it needs well above "weather" temperatures before radiative heat transfer overcomes conductive heat transfer).

Heat transfer is sometines referred to with the single word "heat" only. So in that sense, thermal radiation is "heat" but not the other way around, since conduction is another form of heat transfer, and the use of "heat" can mean more than heat transfer.

2) The energy contained in a system, and which we measure by e.g. sticking a thermometer into it (which by the way works by conduction) is also called "heat". As in if air is at this and this temperature then it contains so and so amount of heat.

Strictly speaking we should use the word "energy" here, and in all my calculations when I use kJ
 (kilo Joules) for latent heat or specific heat and the melting potentiality of air at this or that temperature, it is in fact "energy" we are talking about.

3) In my calculations I have shown that the Warm Air Advection contains nowhere near enough "heat" (meaning energy) to have any significant effect on melting. The paper that you have linked does not claim that the energy carried by the WAA has done any melting. So the paper does not disagree with my calculations.

4) The paper claims that the WAA created circumstances whereby the efficiency of the thermal radiation from the sun was kicked into overdrive. That may or may not be true, I have no idea, but I do question the use of "moist" air when Nullschool shows dry air, comparable to the Sahara at the same time. Perhaps they are right, and the air was "moist" (although where did the moisture come from?), or perhaps Nullschool has it wrong, or perhaps I am misunderstanding Nullschool. Makes no real difference to this discussion.


3
Arctic sea ice / Re: The 2020 melting season
« on: June 02, 2020, 03:19:21 PM »
The record breaking NSIDC sea ice area gains continue. This is the third record breaking daily increase in the last 8 days (5.25,5.31, and 6.1).
Could you please indicate if this is an artifact or if the ice is really freezing exceptionally fast at this moment? The latter seems very unlikely, given the current temperatures in the Arctic.

4
Arctic sea ice / Re: The Arctic for Amateurs and Newbies
« on: June 02, 2020, 02:56:14 PM »
Freegrass, I assume that you are aware of the fact that the Western seaboard of Europe and N.America is much warmer than it should be given their latitude. The standard explanation is that the warm North Atlantic Current and the North Pacific Current respectively keep the Western margins of the continents warmer.

In my understanding, the mechanism by which this happens is by primarily by heat transfer via low pressure areas (storms).

I agree with your assumption that the low pressure areas and storms that form in warmer latitudes will lose their heat when they travel north over colder waters. When they travel over warm currents, the low pressure areas lose less heat than when they travel over "normal" waters. Since due to the coreolis effect, the storm tracks and the currents tend to follow the same east-by-north tracjectory, the two of them together cooperate in transferring southern heat to the northern latitudes.

Basically, when a storm enters the Arctic from the south, it has been prevented from loosing all it's heat by the comparatively warm surface waters of the North Atlantic.

Besides maintining a high temperature due to the warm ocean currents, the stormy winds carry a lot of water in the form of droplets, and their heat capaicity is significantly higher than that of the wind itself. The stronger the storm (effectively, the warmer the ocean area where it was formed), the more precipitable water it will carry. And that makes a very big difference to the ice, making rainy storms from the North Atlantic very efficient carriers of heat into the Arctic.

THe kinetic effect of a storm will be stronger in the latter half of the melting season, when there is more open water, but will never be negligible. But I doubt if the kinetic effect matches the heat effect of a storm at any time, although I may well be wrong.

5
Arctic sea ice / Re: The 2020 melting season
« on: June 02, 2020, 07:10:16 AM »
In June aren't clear skies and forecast warmth just as good as stormy weather to melt out ice?
The sun adds heat to the system. Storms take it away. Because all storms do is they stir up the water, bringing heat to the surface that melts the ice, and vanishes into the atmosphere. Storms add nothing to the energy balance, right?

A storm brings a hell of a lot of warm and wet air from further south. Low-pressure areas form mostly over the N-Atlantic, sometimes as far south as the Gulf region, and flow northwards. They carry massive heat and moisture besides all the kinetic energy that churns the ice up.

Sunny skies vs. strong storm is one of the perennial debates on this forum, opinion seems to me to be that the ice can melt just as easily when battered by a strong storm as it can under direct insolation. But perhaps timing is important here also - a storm at the time of maximum insolation in June an July may cause less melt than clear skies, but later in the season I would guess that a good storm can do much more damage than the sun. Besides, the kinetic factor is probably most effective late in the season when there is more open water to whip up into waves, and easier to push the ice around.

6
Arctic sea ice / Re: Arctic energy balance
« on: May 31, 2020, 06:15:21 AM »
a. Latent heat of ice 333 kJ/kg, specific weight of ice 919 kg/m3, 333 * 919 = 306.027 kJ/m3

Roundly speaking, 3E8 kJ/m3 * 200 km3* 1.000.000.000  m3/km3=6E19 kJ needed to melt 200km3 of ice, 60 billion billion.

b. Windspeed at the time was around 15 km/hour and the Siberian front (EES and Chukchi) is some 2000 km. Ef we generously count the lowest 5 meters of air (assuming some turbulance), we are looking at perhaps 3600 km3 of air in 24 hours.

c Specific heat of air is 1kJ/kg, specific weight 1,3 kg/m3, so specific heat per volume = 0,8 kJ/m3. Temperatures in the EES at the time were around 3 degrees Centigrade, so if we assume that the air loses 5 degrees of heat solely into the melting of ice, the daily volume of air from Siberia would supply 3600 * 1.000.000.000 * 5 kJ = sligtly less than 2E13 J.

d) 200km3 of ice needs 6E19 J to melt, warm air from Siberia supplies 2E13 or 0,00003% of the energy needed.

a. 6E19 J or 6E16 kJ is in result.

b. I think, thicker layer should be considered. Back radiation is comparable with solar globally and more effective to warm up snow or ice.

c. 2E13 kJ or 2E16 J is in result.

d. Very thin layer without water vapor was considered. Yes, It's negligible.

Thanks for pointing out the discrepancies in units. It should have read kJ all the way down. Furthermore I can see that where I say "Chukchi" it should read "Laptev".

The result is so vastly less than anything that could be accounted as likely - i.e. there is no way that the heat wave in Siberia on 10th June 2019 could have melted 200km3 of ice that day, as Phoenix claimed (not suggested, but a straight faced claim).

I am aware that no water vapor was included in my calculation. Nullschool shows that the air was very dry on that day, and anyway the difference in heat capacity of air at varous levels of humidity seems to make hardly any real difference. The specific heat of water wapor is 1.82 kJ/kg compared to ~1 kJ/kg for air. At 5 degrees C and 50% humidity, the proportion of water wapour to air is still very low, less than 1% so making hardly any difference, well within the error margin of ~1 kJ/kg.

The thickness of the air is of course debatable, I used 5 m as a guess, but even if we were include all 10km of the troposhere, the difference is still only 2000 fold, going from 0,00003% to 0,06% of the energy needed to melt 200 km3, totally unrealistic presumption but not getting us anywhere near a real effect.

Also if we raise the temperature, even to the max of 32 degrees, the highest that has ever been recorded within the Arctic circle, the difference is still only 6 fold.

The heatwave in Siberia and the very impressive looking WAA from Siberia in over the EES and  Laptev on 10th of June 2019 had the potential to melt 0,006 km3 of ice. THe EES and Laptev together are around 1.6 million km2, implying a melt of 4mm on that day if all the melt happened in those to seas. Which is not negleglible but nowhere near enough to have any real impact in the Arctic as a whole.

So my conclusion seems to stand: WAA from the continents does not have anywyhere near the capacity to cause any significant melt in the Arctic.

7
Arctic sea ice / Re: DHACSOO - A Durable Arctic Hypothesis
« on: May 30, 2020, 01:04:42 PM »
I am trying to demonstrate that WAA is important because several others have questioned its importance. In the process of exploring that, I've learned a bit from users like Aluminum. 

If you are unable to point out any flaws in my post Arctic energy balance then you will have to give up this WAA hypothesis.

According to my calculations, the amount of heat that can possibly be advected via WAA is so miniscule that it cannot be used to explain anything. This is mostly because of the vast imbalance between the specific heat of air and the latent heat of ice - any amount of warm air that can be advected from Siberia can only melt a miniscule amount of ice.

Unless my math is totally wrong. So please try and work it out for your self. Or accept that your hypothesis is dead in the water.

8
Arctic sea ice / Re: Arctic energy balance
« on: May 30, 2020, 09:51:46 AM »
I think, 7...8 km upward is harder way for photons than 0...1 km downward.

There was strong one in mid-June 2019.



This chart shows a increase in daily melt rate of 200 km3 in response to a well documented Siberian heat wave. Is there any reasonable alternative explanation for the rapid melt increase other than WAA from Siberia ?

How do you know it was in response to a heatwave in Siberia? And have you looked at other explanations? Coincidence is not causation.

Looking at Nullschool and Worldview for the same dates shows winds from Siberia and high air temps over ESS and Chukchi. But also very clear skies over ESS and Chuckhi. The Arctic itself was under a minor low pressure area, but the air seems to have been very dry at the time which may have led to cloud levels that lets a fair bit of solar energy through, and isolates against outgoing infrared radiation as well. I don't know if that was the case, the clouds, as usual, are a wildcard.
 
1. Hypthetical explanation: clear skies and/or high cloud during maximum insolation coincides with a Siberian heatwave and may well share some of the causes, i.e. slow-moving winds and clear skies.

2. Hypothetical explanation: The very real  warm air advection from Siberia clears away the ice  in the ESS and Chukchi (which wouldn't have been there in the first place if it wasn't for being sheltered all winter by Siberia). The appearance of open water under clear skies and massive insolation excelerates melt.

But the biggest problem with your claims Phoenix is that the amount of heat that can concievably be carried by air from Siberia in over the Arctic is far too small to be able to cause the observed melt.

a. Latent heat of ice 333 kJ/kg, specific weight of ice 919 kg/m3, 333 * 919 = 306.027 kJ/m3

Roundly speaking, 3E8 kJ/m3 * 200 km3* 1.000.000.000  m3/km3=6E19 kJ needed to melt 200km3 of ice, 60 billion billion.

b. Windspeed at the time was around 15 km/hour and the Siberian front (EES and Chukchi) is some 2000 km. Ef we generously count the lowest 5 meters of air (assuming some turbulance), we are looking at perhaps 3600 km3 of air in 24 hours.

c Specific heat of air is 1kJ/kg, specific weight 1,3 kg/m3, so specific heat per volume = 0,8 kJ/m3. Temperatures in the EES at the time were around 3 degrees Centigrade, so if we assume that the air loses 5 degrees of heat solely into the melting of ice, the daily volume of air from Siberia would supply 3600 * 1.000.000.000 * 5 kJ = sligtly less than 2E13 J.

d) 200km3 of ice needs 6E19 J to melt, warm air from Siberia supplies 2E13 or 0,00003% of the energy needed.

Of course my calculations could be wildly off, I've been through them a couple of times and I am honestly very surprised to see how little effect the WAA from Siberia has directly according to these calculations. So perhpas somebody could check them.

Phoenix, you should as a minimum be able to do these calculations yourself before making claims such as those above.

9
Arctic sea ice / Re: The 2020 melting season
« on: May 27, 2020, 12:58:57 PM »
Perhaps a bit more effort at content and even calculation, end slightly less emphasis on the condescension.

10
Arctic sea ice / Re: DHACSOO - A Durable Arctic Hypothesis
« on: May 26, 2020, 01:50:49 PM »

Rather than argue, I'll ask a few question.

Let's construct an example. There is a land based heat wave in Siberia near the Laptev Sea with 25C temps over land. The GFS weather map indicates a plume of heat into the Laptev with color coded gradations representing heat in degrees C. Immediately adjacent to the coast is a semicircle which extends 100 km into the Arctic at a temperature of 3C. A bigger area extends beyond to 300 km from the coast at a temp of 2C and a 1C plume extends out to 800 km from the coast.

How do you interpret that?

I see that the sun has warmed the earth and that the warm air from the earth is traveling out over the coast and dissipating as it gets farther away from the coast. Do you see the same thing?

So you give me an imaginary anectdote and want me to say something other than the obvious? Of course there is warm air advection from Siberia to the Arctic at times, and sometimes quite significant, although of course, this is only air moving about, with very low heat capacity, and the reason it gets so hot is that it's not really moving very much in the first place. Because, you see, the sun doesn't shine any harder on continents than other ents.

Heat transfer from the continents is real but is very unlikely to rank higher than at best third place after direct insolation on the ice in first place, and ocean heat absorbtion and transfer (and increasingly, wave action) in strong second place when accounting for ice melt during summer. My own guess would be that third place is taken by low-pressure areas bringing kinetic energy from the southern oceans, stirring up heat from below and bashing the floes together.

The oceans have much higher heat capacity, are much more easy to move around than the continents, and have much lower albedo. So the oceans are the clear winners by far when it comes to collect, store and transfer the heat energy from the sun from anywhere to anywhere when compared to warm air over contintents.

And of course, the flip side of the continental hot summers are the very long and very cold continental winters. Were the Arctic not sheltered in the cold embrace of those massive continents, it would grow much more slowly in winter and disappear easily every summer.

11
Arctic sea ice / Re: What's new in the Arctic ?
« on: May 25, 2020, 01:04:14 PM »
Those pesky rodents get everywhere! Interesting article on glacier mice.

12
Arctic sea ice / Re: The 2020 melting season
« on: May 23, 2020, 07:36:46 AM »
Regarding volume, this year has actually been following 2012 extremely colosely. January had 2012 with slightly more volume than 2020, but February and March had them neck and neck, with April again being slightly in favour of 2012. It's going to be interesting to see what May looks like!

Check out Wipneus' graph.

13
Arctic sea ice / Re: The 2020 melting season
« on: May 23, 2020, 05:59:50 AM »
I would be fascinated to read your interpretation of the factors which determine winter sea ice thickness in which temperature is not an important attribute.

I wont presume to answer for Friv, but speaking for my self, I think that I can easily see a situtation where winter A has lower air temperatures than winter B, but winter B ends up with thicker ice than winter A.

Difference in Fram export is perhaps the most obvious method of ending up with thinner ice in spite of lower temperatures, and ice motion in general is an important factor in determining thickness, and the temperature of the surface waters at the start of the freezing season should also be considered.

The rate of thickening slows down significantly with increased thickness. If there were no winds, waves or currents in the Arctic, and sea surface temperatures were the same going into the freezing season, thickness would be strongly correlated to air temperatues, but even a significant difference in temperatures would only result in a small difference in thickness.

If one year had higher SSTs going into the freezing season, some of the excess heat can presumably be trapped under the newly formed ice, thus hampering the rate of thickening, resulting in thinner first-year ice in spite of lower air temperatures.

And since compaction is the main source of thick multiyear ice, and compaction results not only from movement but also resistance to movement, changes in mobility in general, and direction of movement over time, could make a big difference to how thick the ice ends up being.

And I must agree with Friv, I don't see any bullying.

14
Arctic sea ice / Re: The 2020 melting season
« on: May 21, 2020, 06:37:42 AM »
I realize this measurement could be more accurate, but look at the size of this iceberg which was ejected out of the Fram. It made some rapid progress south and is now just floating off the eastern coast. I will continue to watch it until its eventual demise/

I was going to quibble (as usual) that it was an ice floe and not an iceberg. Then I started to think that in the Antarctic, bigger icebergs than this have been seen. So what about the Arctic, what is the biggest iceberg on record there? Turns out that it is a 100 square mile chunk that broke off Petermann glacier in 2010.

So this is a floe, quite definitely, based on size alone. And if a measurable iceberg were to break off somewhere and start drifting down the Fram I'm sure we would hear about it.

Some 300 miles further south I find a pair of floes, 600 and 400 sqmi respectively, so I guess these big floes are not that unique. But they are good fun, being easy to track.

15
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: May 19, 2020, 04:11:18 AM »
Area loss from maximum this season 2.74 million Km2, 0.45 million (20%) less than the average of 2.29 million km2.

Not that I usually quibble over small mistakes (!) but this made me scratch my head. Isn't it more correct to say that area loss is 20% more than the average to date?

I.e. the average is 2.29, loss to date is 2.74, the difference is 0.45 which is 19.65% of the average.

16
Arctic sea ice / Re: The 2020 melting season
« on: May 17, 2020, 04:21:41 AM »
<snip>  "now we are seeing Swisscheesification of the entire Arctic ..."

      Question 1:  Do those dark areas really indicate low concentration ice or does the sensor get fooled by moisture in the air column between surface and satellite? 

The "swiss cheese" is famous for it's holes, not for any "dark areas". So my comment was only regarding the holes popping up in the ice all around the perifery, much more so than usual at this time of year, as per my feeble and increasingly decrepit memory. And definitely significantly more than 2019 as can be readily seen.

The "dark areas" are of course also much more prominent than usual, or so we seem to think, but I think I've learned the lesson some time ago not to take those too literally. Althogh one does wonder if some sort of Bluecheesefication is underway as well?

17
Arctic sea ice / Re: The 2020 melting season
« on: May 11, 2020, 01:38:05 PM »
Surface temps N of 80N stay close to zero because they are far away from the big heated rocks of Siberia and NA. That's why the ice remains there at the September minimum. Transporting enough heat over long distance to the surface of the CAB ice is not a trivial matter.

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

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

Without the landmasses surrounding the Arcitic Ocean, I'd guess that the ice would disappear every summer. If there was no Antarctic Continent and just open ocean on the South Pole, it would lose all it''s ice every summer (methinks). It's the presence of the vast Antartic landmass that maintains the antarctic sea ice, and the same can be said for the Arctic Ocean, the ice survives by sheltering behind the landmass of America in particular, Siberia to a lesser extent.

18
Arctic sea ice / Re: The 2020 melting season
« on: May 02, 2020, 12:44:08 PM »
Can you see the bear? Anyhow, from the accompanying note posted at nasa.gov, we can read that the bear is, quote, "standing behind Met City near a small lead, likely waiting for a seal". Earlier in the note, we also read that bear, quote, "... sat near a small crack in the ice for almost two hours, likely waiting for a seal to surface".  Seals, i understand, would need open water to come onto the ice, where polar bears could hunt them.

Sometimes when you think something is general knowledge ... but apparently not. Seals nead to breathe. They maintain breathing holes in the ice. Polar bears seek out these breathing holes and wait patiently, up to several hours (often hiding their black snout with a small clump of ice). If the seal does take the change to stick it's nose up for a quick gulp of breath, the waiting polar bear clobbers it and draws it up onto the ice. Seals do NOT crawl onto the ice where polar bears "can hunt them"!

The seal creates breathing holes in the ice as it is forming in the fall, and can maintain them all winter with their paws, sometimes through as much as 2m of ice. But of course, once the ice starts moving and shifting, the seals probably get tempted to use the leads that open op in this way as well, maintaining a short-term breathing hole in a rapidly refreezing lead.

The polarstern people probably were seeing the latter, since they most certainly would have noticed the "aglus" or proper breathing holes if they had been in their vicinity.

19
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: April 18, 2020, 06:51:58 PM »
2) Distance from a large heat advecting land mass. The second criteria is the more dominant variable and has a tad more nuance.

I'm not sure if being close to a landmass is better than being close to open ocean. The oceans absorb much more radiation than land, and the heat transfer of ocean currents has vastly larger potentiality than wind-driven heat transfer by air.

As discussed upstream, the density gradient is a roadblock to ocean heat making it to the surface where the ice is located. The salt in the warm Atlantic ocean water makes it too dense. There's abundant heat in the Arctic Ocean lurking in the subsurface layer below the freshwater lens.


Which is basic knowledge in this forum. And has nothing to do with my (perhaps badly) made point. Which is this:  Open ocean absorbs heat from the sun, no matter what the density. Open land absorbs much less heat.

Your earlier post seemed to indicate that ice being close to a landmass would somehow receive a warming boost because of air advecting over the warmed-up land and out over the ice. But I would say that being far away from a landmass would give added boost to melt during summer, by air advecting over open ocean which, as I've said, absorbs much more heat than dry land and has therefore more heat to give to any passing air (besides being able to transfer the heat itself to some extent).

20
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: April 15, 2020, 04:44:19 AM »
I guess apocoalypticists are constantly seeing signs of imminent collapse. And have been since at least Ramses' time. I on the other hand, who am absolutely certain that our human civilisation will survive both Covid-19 and AGW, see amazing resilience and innovative adaptation everywhere.

21
Arctic sea ice / Re: "Stupid" Questions :o
« on: April 15, 2020, 04:40:08 AM »
I don't think you're wrong. Sublimation requires energy, and if water evaporates (or ice sublimates) into dry air, this leads to a drop in localized temperature.

The Arabs were famous for having flowing water and even small fountains next to their pavilions and maqhaas, as a low-technology air conditioner, utilizing the cooling effect of evaporation.

Same will happen with ice even in cold circumstances - if the air is very dry then some ice will sublimate and the air gets even colder. But of course, warm dry air is a true ice killer (e.g. foehn winds or the Chinook, the adiabatic effect often causing surprisingly hot air to stream over ice and snow), and dry and sunny weather also sees ice and snow disappear very quickly.

22
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: April 14, 2020, 06:44:27 AM »

.....But once Atlantification starts removing the fresh water lense.....


Perhaps you can expand on this piece. My understanding is that the fresh water is the surface layer of the Arctic because it is less dense than warmer Atlantic water because the salinity impacts density more than the temperature difference. Incoming Atlantic water does not generally displace the surface layer, it exists beneath it.

The process of removing the fresh water lens that you refer to isn't clear.

Note: Fresh water exits the Arctic all the time via Fram Strait and enters via river runoff. How would "Atlantification" accelerate the departure of fresh water?

Good points, and I won't pretend that I know more than a smidgeon of any potential answers. But I'll try anyway!

The density of water changes with salt content and temperature. So a cold fresh water layer that competes with a salty warm current is not obviously going to win. The whole AMOC concept of the warm surface currents steadily getting colder until they start to sink does not assume that it is the fresh-water lense that pushes it down. With the ongoing increase in air and ocean temperature, any sinking tendency of the warm surface waters is going to steadily decrease.

"Atlantification" is what scientists have apparently called the changes that have happened in the Barents as it has transitioned from a mostly ice covered sea to mostly ice free. As I understand it, wave and wind action mixes the waters sufficiently to remove the "fresh" water surface that can freeze rapidly.

As for the fresh water lense - in my understanding, this exists under the ice in winter and is added to by summer melt, but once the ice is gone, wave action has the potential to break up this lens and increase mixing from below. This of course is entirely dependent on there being a big enough area of open water to generate decent wave activity, and that bathymetry allows for there to be any significant deeper layers to mix with.

So if we call it "Atlantification" when wave action mixes the surface fresh waters with deeper salty (and warm) waters, then clearly this will not happen over the Siberian shelf or, in any near future, along the CAA coast. But the entire Atlantic front, as well as a decent enough part of the Pacific front, should be open to this process.

So is there a natural barrier to this process of Atlantification along the Atlantic front? Perhaps. Or perhaps it's simply a creeping ongoing change that is steadily working it's way northwards.

23
My experience of snow in Iceland is this: It may snow a lot but if there is any wind at all (which is most ofthe time), the snow gets blown about before settling down and in some cases simply disappearing out over the ocean.

In a snow storm, all the roads close but once reopened, they will need to be constantly cleared for several days while all the snow is still blowing around. Eventually most of the snow "disappears" (blown out over the ocean?) and things settle down.

I used to go skiing in winter, mostly long-run skiing, and even after long periods of lots of snow the average snow cover would be from a few tens of centimetres of snow accumulated in dips and hollows, with bare ground inbetween. And and this part of Iceland is definitely not a desert, recieving upwards of 1000 mm of precipitation every year

In Siberia, the snow can't just "disappear" unless it blows far enough south to simply melt. But average precipiation is very low in many areas, as low as 150 mm per year, so it is easy for me to visualize a tundra where every bump, hillock and tuft of grass is mostly free of snow, with a few centimetres lying inbetween.

If so, the area would be less than totally white in satellite images.  The image posted by Pearscot here shows large areas of northern Greenland with a distinctly yellow brown hue. This is probably exactly the sort of thing I visualize for Siberia.

My Ethiopian internet connection doesn't really allow for satellite image browsing, but I had a (slow) look at yesterdays Worldview and saw what I remember seeing regularly: Most of the "snow-covered" parts of Siberia look deciedly off-color except for maybe a 50-100 km stretch along the coast.

So this white coastal area matches pretty well up with the purplish to orange colors on the snow depth map - i.e. somwhere between 12 and 36 cm. on average. My guess is that snow from further south blows into this area and settles down, Looking at the satellite imagery in Google Maps the same areas seem decidedly flattish, and most of them get very little if any sunlight during the winter months.

24
Arctic sea ice / Re: The 2020 melting season
« on: April 13, 2020, 06:10:18 AM »
I don't get it. How can this scale be in cm? Shouldn't that be decimeter? 72 cm is less than a meter. 70 dm is 7m.

Snow is rarely very thick in flat areas without tree cover. The wind tends to blow it away, but of course there can be very deep accumulations where an obstruction gives some shelter.

The very deepest even snow layer I ever saw was about 2 m, covering a flat valley floor perhaps 2 or 3 km wide. The surrounding mountains were mostsly windswept and bare, so averaging over the entire area would probably be well under 1m.

25
Arctic sea ice / Re: The 2020 melting season
« on: April 12, 2020, 06:05:30 AM »
Good moderating there Oren!

26
Arctic sea ice / Re: Global sea ice area and extent data
« on: April 06, 2020, 08:47:38 AM »
Good one!

If we keep to the Greek naming tradition, then apparently all penguins belong to the sphenisciformae which is a typical greek - latin construct, with spheniscos being Greek for wedge.

So penguins are named "wedgeformed", probably based on the shape of their wings.

And the constellation could be called Spheniscos Minor and the continent Sphenisctica rather than now clearly obsolete Antarctica.

27
Arctic sea ice / Re: Global sea ice area and extent data
« on: April 06, 2020, 06:27:34 AM »
Arktos is the ancient Greek name for bear.  So the Arctic region was named after the polar bear.

The greeks who coined the word had probably never heard of the polar bear. They were familiar with bears in their own mountains and had named the constellation the Great Bear after that animal.

So "arktikos" is probably, according to current thinking, referring to the great northern constellation Great Bear, and by extensions, all northern regions.

"Arktos" on the other hand seems to refer to authority, sharing a stem with "arxo" meaning "command" or "primary", as in "archaic", "archbishop" and "archangel.

28
Arctic sea ice / Re: Tides
« on: April 04, 2020, 08:25:44 AM »
Quote
Let's see if he comes around this time.

Nope. Just keeps spamming.

I'm saddened, blumenkraft. I truly expected better of you. Do you think that honest disagreement, dissemination of information and willingness to debate are "spamming"?

29
Arctic sea ice / Re: Tides
« on: April 02, 2020, 07:56:04 AM »
Moving on from my last post: Of course, as any pedant can point out, the long-term tidal effects are due to the fluctuating nature of the tides.

But in the large scale of things, these fluctuations have almost no impact per se. It is the cumulative impact that is real, but the impact of indivual tidal movement is purely local and temporal, with any movement being almost exclusively up-and-down and back-and-forth, so the net effect is usually zero.

Some people have the pet ideas that they can somehow predict (or explain) daily, weekly or monthly changes in the large scale behaviour of Arctic sea ice by referring to the phases of the moon. Every such claim is unsubtantiated by both basic science and current scientific research.

30
Arctic sea ice / Re: The 2020 melting season
« on: April 02, 2020, 07:43:06 AM »
binntho, there is a thread for that now. You might ignore the science there.
You might try reading what people post!

31
Arctic sea ice / Re: The 2020 melting season
« on: April 02, 2020, 07:27:25 AM »
Bashing peoples' pet theories is never going to make one popular, and having a low silliness tolerance threshold can be a curse.

My current tidal rant started when somebody rambled on about visible changes in Fram export being somehow linked to the tides. Total rubbish in my mind, as are similar claims that have been made previously.

Gifs and anectdotes are not evidence in this case. There is absolutely no science to back up the Fram export/tide effect, there are is no data, there are no chains of causality that can be brought to bear to support such claims.

Somebody mentioned the bathymetry thing above. That was another frequently banded-about pet theory that many people referred to but did not really seem to understand. At least, nobody was able to explain what they were talking about when pushed. Eventually a few of the more knowledgable of the members managed to piece together the scientific evidence and the data (and I did a lot of research myself) and the bathymetry thing was resolved - I accepted that it was a real thing in very many areas of the Arctic, and I hope that some others managed to understand why that is the case. Was forcing people to look at the science behind their claims such a bad idea? Perhaps if this was the forum of a religious cult, yes, but not in a forum for scientific discourse.

The same goes for the tidal debacle. My own research into the matter has not turned up the least iota of support for a large scale and fluctuating tidal effect on ice movement in the open ocean. Nobody on this forum has been able to show any supporting evidence. The ongoing Mosaic expedition would be a prime example - have they ever mentioned tidal effects on the movement of ice around their vessel? Not that I've seen.

Pointing out your previous failure to provide evidence, and me still going on about it, does not make me more likely to accept your claims. I'll move my own rants over to the newly created tidal group, and I look forward to the company of anybody who would want to join me there in the sport of exasperating and irritating each other.

32
Arctic sea ice / Re: The 2020 melting season
« on: April 01, 2020, 09:13:22 AM »
The constant flow of low-pressure areas up the North Atlantic cause the exact same up-and-down movement as the tidal effect, due to changes in pressure. And changes in gravity (i.e. tidal effects) are of course de facto changes in pressure.

Nobody has ever claimed that this constant up and down movement due to low pressures moving over the surface can ever have any effect on the lateral movement of ocean waters (or surface ice), except for the purely coastal effect (the same as the tides).

So how does the tidal effect manage this?

33
Arctic sea ice / Re: What's new in the Arctic ?
« on: February 24, 2020, 06:42:42 AM »
Interesting article published by the Scripps institute about methane in permafrost.

https://scripps.ucsd.edu/news/climate-destabilization-unlikely-cause-methane-burp

Quote
“Anthropogenic methane emissions currently are larger than wetland emissions by a factor of about two, and our data show that we don’t need to be as concerned about large methane releases from old carbon reservoirs in response to future warming,” said Petrenko.  “Instead we should be more concerned about the methane that is being released from human activities now.”

34
Arctic sea ice / Re: "Stupid" Questions :o
« on: February 10, 2020, 02:30:48 PM »
Would microwaving anything sent from China (unless that would damage it) do any good to make extra sure it is safe?
And how on earth would we know? Is this forum suddenly authoritative on virus pandemics and microbiology? My totally uninformed guess is that microwaving would make no difference, unless you soaked the package in water first (microwaves only work on water molecules), probably a good idea to deep-freeze it afterwards in 100 proof Tennesse whiskey!

35
Arctic sea ice / Re: "Stupid" Questions :o
« on: February 09, 2020, 08:57:42 AM »
  If you want to really freak out, read about the first versions of new batch of CMIP6 climate models generating an ECS much higher than the previous generation.  Only a small portion of the CMIP6 models have published output yet, so this is still a developing story.

One at least of the reasons for the higher equilibrium of the new model runs is the inclusion of more robust data on cloud formation - by far the biggest unknown in the whole AGW saga. It turns out that rather than being neutral, cloud formation could well be a positive reinforcement in a warmer world.

An excellent overview is here, from a Yale Universtiy on-line publication.

36
Arctic sea ice / Re: The 2019/2020 freezing season
« on: February 07, 2020, 06:50:16 AM »
Moved from the data thread after a kindly reminder ...  8)

Before we all start to get too expressive about excessive extent, I'd like to point out that we are talking about comparatively small differences between the various years. Random weather effects  such as wind driven export could easily account for all the variation we see in the last decade.

And of course, as much cleverer people than me have decisively shown (I trust ...) there is absolutely no correlation with summer extent. Which tempts me to conclude that there is no correlation with temperatures either - i.e. winter extent will be more or less what we are seing now, with small random variations, until at some point in a (probably) distant future when winter refreezes doesn't manage to fill the entire Arctic.

37
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: February 04, 2020, 01:43:49 PM »
In other words, the 17 years with lowest sea ice extent for the date are among the first 20 years of the 21st Century. A clear perspective of long-term trend of global warming, thanks weatherdude.

Take into account that this is all based on data from 1979 and on. There is no real data from before ( there are some very bad satellite pictures from 1975'ish). Before that there is reported anecdotal data from explorers and locals that in some cases point to low arctic ice.

You might want to look at this 1947 report from DMI on the state of the Arctic Sea Ice.

As you probably know, 1947 was at close height of the mid-19th century warm peak. The August extent in the DMI report is of a similar magnitude to what the winter extent is likely to be this year, so between 2 and 3 times more than this decade.

So any anectodal evidence for low sea ice extent from before 1979 will have to be taken with a ton of salt. Or rather, tied to a rock and thrown overboard. Any and all documentation from before 1979 shows greater sea ice extent than what we are seeing this last decade.

This paper from 2001 shows an estimate for the 20th century. August minimum in 1947 would have been around 12 million km2.

And another paper for 2009 seems to agree roughly, taking the estimate back to 1880, which may well have been the maximum sea ice extent since the last ice age.

Having said that, apparently we have to go at least back to around 1200 CE to see extent similar to what we have been seeing in the last decade.

38
Arctic sea ice / Re: The 2019/2020 freezing season
« on: February 01, 2020, 10:17:25 AM »
grixm: Brilliant! Good statistics, but what's more, actual predictions to add spice to the winter dullness. Can't wait to see how February and March turn out - and of course, to match it up to the eventual September average extent.

Which brings me to a niggle: Your graph for January predicts a September average of 4.3 Mkm2 and not a September minimum of 4.3. Correct me if I am wrong! NSIDC September average for 2012 was an amazing 3.6 but both 2007 and 2019 came in at very close to 4.3.

As for the possible mechanism behind this statistically apparent correlation: The capping of excess ocean heat by an unusally rapid freeze and larger winter extent has already been mentioned. Another mechanism could be to do with weather, in two (possibly related) ways: The same winter weather that produces rapid freezing also results in stronger preconditioning come spring, or alternatively, a bigger extent at maximum increases the changes of stronger preconditioning weather in spring.

39
Arctic sea ice / Re: The 2019/2020 freezing season
« on: January 31, 2020, 03:02:51 PM »
Ah yes, a classic example of cherry-picking the data ...

Here's a graph covering the years 1979-1919 showing March average on Y axis vs. September average on X axis, from NSIDC.

The correlation is very strong but equally meaningless. Both winter max and summer min have trended downwards with time, and the plot says absolutely nothing more than Niall's graph further up.

I.e. it is not possible to predict with any certainty what the summer mininum will be based on the winter maximum that year.


40
Arctic sea ice / Re: What's new in the Arctic ?
« on: January 28, 2020, 09:49:10 PM »
Please edit links down to their normal format:
My bad, being lazy and quite likely pre-senile as well. But I'll strive for improvement!

41
Arctic sea ice / Re: What's new in the Arctic ?
« on: January 28, 2020, 09:11:20 AM »
Interesting article on the effects that the changes in Arctic sea ice cover may be having on tropical weather systems.

Turns out that even if El Ninos do not effect the sea ice, less sea ice may effect the specific location of El Ninos which again has a domino effect on other weather patterns.

https://insideclimatenews.org/news/26012020/arctic-sea-ice-melting-tropical-weather-el-nino-climate-change

42
Arctic sea ice / Re: The 2019/2020 freezing season
« on: January 27, 2020, 01:12:11 PM »
My guess is that, based on my understanding of thermodynamics, more heat is lost in areas with combinations of highest temperature difference and lowest relative humidity (e.g. Arctic regions, which typically have the highest spread between high and low temperatures on any given year). In such areas there is the greatest differential between the heat source (earth) and heat sink (outer space), coupled with the lowest combination of greenhouse gases (water being by far the most important).

So you quote Feeltheburn almost verbatim, only changing the paranthesis:

(e.g. deserts, which typically have the highest spread between high and low temperatures on any given day). 

The point being? But since you seem to dispute Feeltheburn's post (albeit in a rather underhand way), I was tempted to do a Google search on "where does earth lose most heat" and the first link gave me this underlying image, from Nasa.

Seems that Feeltheburn's understanding was spot on, at least for the month of September 2008. And I'd be very much surprised if the Arctic (or the Antarctic for that sake) would show enough heat loss in their respective summers to trump the tropics or the mid-latitude desert bands on an annual basis.

43
Arctic sea ice / Re: The 2019/2020 freezing season
« on: January 23, 2020, 06:49:25 AM »
I'm new and not up to speed on all the intricacies of the Arctic melting and refreezing but wouldn't the salinity concentrations and the dilution of the Arctic seas from the vast amounts of freshwater entering the Arctic from melting glaciers (especially Greenland) cause a significant increase in ice extent since the less saline water freezes more easily (higher temperature) than the albeit thinner and more prone to melting the next melt season?

Well as for the melting Greenland glaciers, along the east coast, the coastal currents would push any meltwaters southwards, then north into Baffin bay where any meltwaters from the Western coast would be added to it and then make it's way west and south again and into the Atlantic. Since this happens in summer, any meltwaters from Greenland would long have disappeared from Arctic waters before areas like northern Baffin start to refreeze (late October / early November)

I'd guess that any glacial meltwater from other sources reaching the Arctic Ocean itself would be hugely dwarfed by the fresh-water rivers that drain into it.

So no - I wouldn't expect glacial meltwaters to have any noticeable effect on ice extent by itself.

44
Arctic sea ice / Re: The 2019/2020 freezing season
« on: January 15, 2020, 09:56:21 AM »
Interesting.

What are the best ways to see cloudiness in the arctic?

https://climatereanalyzer.org/reanalysis/monthly_tseries/

Here is a plot showing the opposite of what is claimed about increasing cloudiness.

Very interesting. Cloud cover is not everything of course, and in the Arctic, low-lying fog is quite common and probably not counted as cloud. I wonder if anybody is qualified to claim anything about changes in fog prevalence in the Arctic?

Also it'd be interesting to see if humidity has changed (or rather, the total amount of water vapor - which I presume has increased).

45
Arctic sea ice / Re: Near Real Time Sea Ice Volume
« on: January 14, 2020, 07:32:39 AM »
Using a preliminary GISS-equivalent temperature for December and filtering out those short-term influences shows 2019 as the warmest year since modern records began.
Ocean temps apparently reached their highest levels yet, according to this article in the Guardian.

2019 shows a marked jump on the year before, also interesting is the apparent change in slope after 1990.


46
Arctic sea ice / Re: The 2019/2020 freezing season
« on: January 05, 2020, 09:30:05 AM »
You still don't get it what we're fighting for, do you? Climate change is gonna kill everyone on this planet. So excuse me for not feeling sorry for a few idiots that would STILL keep those coal mines open after their entire house burned down.
It's not going to kill everybody on the planet. What rubbish. But attitudes as those expressed here are responsible for killing a hell of a lot of people through the ages. The righteousness of the apocalypticists is the biggest threat to human societies everywhere.

47
Arctic sea ice / Re: "Stupid" Questions :o
« on: December 31, 2019, 11:35:26 AM »
Tom, it is "conservation of energy". Matter consists of energy (and not the other way around).

Cassandrists, Malthusians and Luddites are ten a penny at all times and in all societies. We humans seem to have an inbuilt liking for predictions of doom - nobody became famous for saying that it's all going to work out fine, in fact, those who dare voicing any degree of optimism for the future of our species seem to become automatically vilified.

And when it turns out that the world didn't end, you write a book about why not, and find that you made a small error, and the end of the world is next year .. or perhaps the following year ...  So reading a 20 year old book about why predictions made 50 years ago have not become true yet (but will, definitely, within the next 5 years!) is not really my idea of a productive time.

48
Arctic sea ice / Re: "Stupid" Questions :o
« on: December 19, 2019, 08:09:30 PM »
No the days were shorter because the planet turned faster.

Bonus question did years exist before calendars?
Stonehenge is a calendar.
Is it? Well as a minimum it shows that they had celendars back then. But I prefer to see Stonehenge as an early silicon based computer running at 1 Hz / annum.

49
Arctic sea ice / Re: "Stupid" Questions :o
« on: December 19, 2019, 08:06:14 PM »
The sixth power, depending on how you calculate it, is either a squared cube or a cubed square.
And what on earth is "a cube squared" and what has it to do with anything?

50
Arctic sea ice / Re: What's new in the Arctic ?
« on: December 17, 2019, 06:22:45 AM »
I'm hoping the magnetic poles reverse.
Why?

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