Support the Arctic Sea Ice Forum and Blog

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - binntho

Pages: [1] 2 3 ... 24
1
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: Today at 06:04:28 AM »
That would be a reasonable request in theory.  In practice, how can we separate the fast ice and icebergs from the surface ice?  The satellite data will treat them all equally.  Also, at what point out from land can we separate fast ice from surface ice, and when does a break in the surface ice transition to an iceberg?  When we discuss radiant energy, does not all ice behave similarly?

i don't think the satellites used for sea ice extent would be ble to see most icebergs, (which btw are all produced by glacier calving). Besides most icebergs in the northern hemisphere  have their origins in Greenland glaciers along the east and west coasts and drift southwards,

Fast ice does not break up into icebergs. And true fast ice is very rare in the Arctic, I doubt that there are more than a few hundred km2 in total. Besides, once faced with an open ocean, the remaining fast ice would probably disappear very quickly.

2
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.

3
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.

4
Arctic sea ice / Re: Tides
« on: April 04, 2020, 11:48:09 AM »
Binntho you keep ignoring the huge difference in depths between bodies of water, even away from your beloved coast

I don't think I do. There is a difference between continental shelves and the deep ocean, of course there is. But the tidal effect is almost all to be found in the deep ocean - both when it comes to area and when it comes to volume and when it comes to sheer energy.

Besides, with the tidal effect being cyclical, expecting any effect to be more than an up-and-down and back-and-forth movement, and therefore essentially zero over any given day  would require a lot of explaining. The tides do cause currents in certain coastal areas, and these currents are able to move ice in one direction in the morning and the other direction in the evening. So what? This is such a collection of basic facts that they should hardly need to be mentioned.

Quote
. You keep repeating the mantra of the "deep ocean", well if all the oceans were uniform some of the effects being thrown around here would not exist. And yet you ignore this and therefore keep being surprised that people claim there is an effect.

I'm not surprised when people claim real effects, effects that all can see and many of us (me included) have experienced directly.

What surprises me is that most of the members of this forum are unable to see that wild claims about "tidal surges" in the deep Arctic, and that Fram export can be linked to the phases of the moon, are so very very wrong.

Quote
Until you acknowledge this no progress will be made.

But I do acknowlege it! I acknowledge all knowledge. I acknowledge all facts. I do not acknowledge wild theories without basis in reality.

The various scientific papers, I acknowledge them all. The gifs that blumenkraft and others have shonw me I acknowledge them all. I have never claimed otherwise.

But I will never acknowledge wild theorizing without any basis in reality. And I am not at all happy with the seeming lack of understanding of basic physics amongst the majority of posters in this forum.

Otherwise, my refusal to admit a moon-phase effect on Fram export would never have lead to this discussion!

5
Arctic sea ice / Re: Tides
« on: April 04, 2020, 10:14:09 AM »
If your DTU Space-derived map is nearly correct, the sea level in the Greenland Sea will be half a meter lower twice a day than sea level North of the 80 degrees parallel in the Fram Strait.

This means that there is an immediate "pull" southwards twice a day, which may contribute to the "fracking" or "cracking" seen these days north of 80N.

It is the "pull" that does it, not the "push" at high tide in the Greenland Sea.

You imagine that because the surface is lower in one place than it is in another, then there should be a gravity-induced pull from one to the other. This is intuitive, but wrong when it comes to tides.

Just to be clear: We are talking about deep ocean, hundreds of km from the nearest shore. So there is no coastal effect.

The tides move up and down due to changes in gravity. So the surface is always at the same "level" of gravity, whether it is one meter higher or lower.

For there to be a gravitational pull (e.g.. down a slope) there has to be a difference in the gravitational pull at the surface at the top of the slope and at the bottom - there has to be a difference in what is often termed "potential energy" of any object on the upper and the lower parts of the slope. But since the graviational pull at the surface is the same (because the surface responds to changes in gravity by going up and down), no potential energy difference exists.

There is therefore no "pull" from the tide-lowered South Greenland sea, just as there is no "push" from the tide-raised South-Greenland sea, when compared to the Fram Strait boundary.

6
Arctic sea ice / Re: Tides
« on: April 04, 2020, 09:16:10 AM »
Binntho, nice to know that you are safely up into the mountains in Africaåq and away from the frigid ocean.

Thanks. It's a little bit strange thinking of this as being "up in the mountains" since I'm sitting next to a huge lake in an extensive flatland surrounded by mountains. But on the other hand, I am at an altitude of almost 2000 meters.

The nearest ocean is not "frigid", in fact, you would have difficulty swimming in the 40+C surface waters due to heat. And in Iceland, we don't usually consider the ocean "frigid" since it is more often than not warmer than the air!

7
Arctic sea ice / Re: Tides
« on: April 04, 2020, 09:12:56 AM »
Please reconsider, whether such a twice-daily "pull" of low water tide in the Greenland Sea would have have any noticable effect on the export of polar sea ice.

What "pull" do you mean. What is pulling on what, and how?

And if a twice-daily "pull" then there must be an equal and opposite twice daily "push"? Leaving us with no net effect at all.

8
Arctic sea ice / Re: Tides
« on: April 04, 2020, 09:00:37 AM »
This whole tidal debate has in my mind always been about coastal vs. total.

The total effect of tides on water movement are totally different from localized, and coastal, effects. Lateral movement is obvious in the latter, negligible in the former.

The most recent example of lack of understanding of how tides work was the claim that the phases of the moon could somehow visibly affect Fram export.

The one before that was when someone talked about a "tidal surge" entering the Arctic Ocean.

What perhaps surprises me most is not that a few simple souls can make such claims, but that the rest of this forum does not understand why those claims are so wrong.

And unfortunately, blumenkraft and other very valuable members of this forum continue to refuse to understand why silly claims about the tides simply cannot be right. There is no tidal surge in the Arctic ocean (nor can there be), and the phases of the moon do not visibly affect Fram export.

9
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"?

10
Arctic sea ice / Re: Tides
« on: April 04, 2020, 08:24:40 AM »
In the prevous post, the tidal component in the Arctic could not really be seen. But a very quick Internet search found the following, which I must say surprised me very much.

There hardly seem to be any tides in the Arctic at all! So I think we can lay to rest once and for all any discussion of whether and how the tides can affect sea ice in the Arctic ocean.

The image is from here.

11
Arctic sea ice / Re: Tides
« on: April 04, 2020, 08:15:47 AM »
Most ocean waves are not pressure waves. Tsunamies are the only large-scale example I can think of.  The tidal "wave" is therefore definitely not a pressure wave as such.

The two daily waves that seem to propagate from west to east every day are caused by the tidal effect being (relatively) static while the Earth rotates underneath (picture 1)

Density of water changes with pressure (see picture 2), and even if the effect is small, the oceans are very deep. So the biggest effect happens over the deep oceans.

But where is the biggest tidal effect felt? This is much more complicated. There is an west-to-east component and even a slight south-to-north (e.g. around Iceland, the tide hits the south-west first, and the north-east last). But the shapes of the oceans, their bathymetry, and the relentlessness of the tidal cycle, results in the tidal effect being very strangely distributed (see picture 3)

12
Arctic sea ice / Re: Tides
« on: April 04, 2020, 07:54:08 AM »
uniqorn - my apologies if I have misconstrued your comments. I have read your posts, and commented on some of them for some time, and you have on occasion commented on mine. But your contributions to this forum outweigh mine by a long shot, it is I who benefit from reading your posts and most likely not the other way around!

Seeing as how you have dregged up some of my earlier contributions, I would like to clarify:

I have "always" (let's say, for the last few decades), been of the opinion that tidal movement is primarily an up-and-down movement caused by changes in gravity.

Ghanges in gravity cause changes in pressure, which causes the water column to expand and contract. Changes in atmospheric pressure also cause changes in pressure within the water column, causing the water column to expand and contract. Hence the two phenomena are linked, and they are also of a similar magnitude.

If we were to put a number on the magnitude of the tidal force on the oceans of the world, then by far the largest number would be put on vertical movement in deep, open water. This does not exclude lateral movement in shallow coastal areas.

Tidal currents in the North Sea, tidal swirls over shallows and in and out of fjords along the Greenland coast, all of these are real and natural and should not surprise anybody. The existence of these does NOT imply that similar forces are at play in the open oceans.

And this is where I think that most of the current misunderstanding of tidal movement stems from: Very many people are aware of, and even have direct experience of, strong tidal movements close to shore. They extrapolate this and think that the 450 km wide Fram strait must have similar tidal currents. Well it doesn't.

13
Arctic sea ice / Re: Tides
« on: April 04, 2020, 07:35:24 AM »
I must begin my post by apologizing for my silence - I am currently isolated in a three-house compound within spitting distance of the source of the Blue Nile, along with 3 "adopted" young men. Internet connectivity here is limited and fluctuating (albeit not with the phases of the moon as far as I can see). My work is heavily dependent on Internet access so most of the available bits have to be utilized for work rather than play.

On other personal notes (since somebody saw reason to wonder), I am an Icelandic national and well acquinted with tidal forces in coastal areas around Iceland that see some of the biggests tidal fluctuations in the world (although nowhere near as impressive as on the Canadan Pacific coast, or so I hear). My experience does include being severely seasick in small vessels during storms,  but the shipboard episodes of my life are thankfully few and far between.

Having lived on the east coast of Sicily for many years has also acquainted me with the strong coastal current that arises every now and then and some say are linked to the tides. But tidal movement in the Mediterranean are mostly very small and complicated, with the Messina current being well established as a tidal current, resulting from the (small but still existant) out-of-phase tidal movements oft he Ionic and the Tyrrhenian seas.

14
Arctic sea ice / Re: Tides
« on: April 02, 2020, 08:29:14 AM »
Full disclosure, this is what i wrote:

Thank you. First I'd like to say that I am not the best at reading what other people write! So cricising you for that was somewhat hypocritical.

I'd like to refer you to uniqorn's "where does the water come from" comment above. Even the best and most valuable of members, that have been providing the rest of us with a constant and positive input (such as yourself) can be totally off when it comes to such basic scientific facts as what a pressure wave actually is.

That is why I dare! Because none of us knows all, but some of us have a better basic understanding of physics than others. This basic understanding can of course lead you into the briar patch, but when something jars against it, I not only dare to respond, but I do.

So silly claims, such as that the phases of the moon can effect Fram export, will be bashed by me now and in the future.

15
Arctic sea ice / Re: Tides
« on: April 02, 2020, 08:12:18 AM »
blumenkraft has sent me a private message taking umbrage at my lack of acceptance of silly claims such that changes in Fram export can be caused by changes in the phases of the moon. Well bless him, but I guess our tempers collective and individual are not what they should be now, these corona virus times!

16
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.

17
Arctic sea ice / Re: Tides
« on: April 02, 2020, 07:44:05 AM »
Quote
In the Arctic sea-ice pack, ice motion is largely a response to local winds and ocean currents (including tides)

Link >> https://www.cambridge.org/core/journals/journal-of-glaciology/article/meso-and-microscale-seaice-motion-in-the-east-siberian-sea-as-determined-from-ers1-sar-data/E0A7D4458296C2D4D0F6A331436EC69D/core-reader

Yes blumenkraft. I've read similar papers online. None of them supports claims such that Fram export can change in accordance to the phases of the mooon.

I'd like to point out what I wrote yesterday:

HOWEVER!!!!!

Long-term movements of ocean currents ARE effected by the tidal pull of the moon. So the effect is not non-existent in the open ocean, but it is NOT a fluctuating effect. In other words, no research i've found indicates that changes in tidal movement on a daily or monthly basis has any discernible effect.

The existence of tides has a constant effect, not a fluctuating effect, changes in the tides on a daily or monthly  basis does not effect the large scale state of the ice in the Arctic Ocean.

18
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!

19
Arctic sea ice / Re: Tides
« on: April 02, 2020, 07:40:42 AM »
ty kassy,

 for backing up, with real evidence, my feeling that tides could influence the melting of Arctic ice in the Nares and throughout the Arctic.

to those who say ' show me where it says', consider yourself as having been shown....

great work, kassy !!!

td

Yes, thanks Kassy. I've read several similar papers. Not one of them supports claims such as the one that set off the current debate: That changes in Fram export that we have seen over the last months are somehow linked to phases of the moon.

20
Arctic sea ice / Re: Tides
« on: April 02, 2020, 07:38:09 AM »
When the tide goes up, where does the water at the bottom come from?

Yes, uniqorn. You are here expressing one of the fundamental misunderstandings of how tidal waves (and pressure waves for that matter also) actually function.

The tide goes up because the water column expands due to changes in pressure, with the change in pressure being caused by gravitational changes.

Same happens when changes in atmospheric pressure cause corresponding changes in sea surface (appr. 1 cm per millibar, see here). Whithin the Northern Atlantic and the Arctic, differences in atmospheric pressure from one place to another can easily exceed 50 mbar, leading to a difference in sea level of half a metre. Again, this is due to expansion and contraction of the water column.

Sea level rise due to the tidal effect is usally at the same or smaller scale as this, with localized exceptions (e.g. south of Iceland and along the European Atlantic seabord, where in excess of 1 metre can be seen).

But  most of the world's oceans only see a tidal fluctuation of less than 50 cm, see here.

EDIT: Expanded slightly.

21
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.

22
Arctic sea ice / Re: The 2020 melting season
« on: April 01, 2020, 09:51:58 AM »
Last time we talked about this i gave you multiple GIFs illustrating and proving my point. You all dismissed them without counterargument. So no, i will not do it again.

I remember those gifs. There was no point in responding to them because they either showed the coastal effect. Which I keep saying is real, but of no importance since it only reaches a very short distance away from the coast. Or they were not really conclusive, more a question of wanting to see something.

Besides, the coastal effect is mostly back-and-forth movement caused by the up-and-down movement in shallow waters, and should therefore have an extremely limited (if any) effect on the movement of ice and water in the open ocean.

The open ocean, thousands of kilometers from side to side, is what we are talking about here. And the lateral movement of ice (and water) in the open ocean does not fluctuate with the tides.

HOWEVER!!!!!

Long-term movements of ocean currents ARE effected by the tidal pull of the moon. So the effect is not non-existent in the open ocean, but it is NOT a fluctuating effect. In other words, no research i've found indicates that changes in tidal movement on a daily or monthly basis has any discernible effect.

The existence of tides has a constant effect, not a fluctuating effect, changes in the tides on a daily or monthly  basis does not effect the large scale state of the ice in the Arctic Ocean.

23
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?

24
Arctic sea ice / Re: The 2020 melting season
« on: April 01, 2020, 09:08:59 AM »
Tidal effects (other than a smooth up-and-down motion) are strictly limited to the narrow coastal strip

You were wrong about this the last X-times you stated it and you are wrong now again. You can't think ice movement without also taking tides into account.

Therefore, the tide movements are absolutely not off-topic in this thread.

So tell me how the tides move the ice! What research has been done on this pheomenon, and what are the particulars of the kinetic transfer from tidal movement to ice movement.

I have never seen anybody give any explanation for their strange fixation on tidal effects, so I will continue to claim that they do not exist.

25
Arctic sea ice / Re: The 2020 melting season
« on: April 01, 2020, 09:06:18 AM »
Good points Glen. My take on the linear vs. exponential (or other curved) declines is that the underlying decline is linear to the extent that it follows the near-as-makes-no-difference linear increase in global temperatures (so far).

On the other hand, I would expect acceleration at some point. So linear now, accelerate later. This is purely intuitive so I won't make any big claims!

26
Arctic sea ice / Re: The 2020 melting season
« on: April 01, 2020, 05:00:28 AM »
We're half-way between peak tides  ...

Tides have no effect on Fram export. Tidal effects (other than a smooth up-and-down motion) are strictly limited to the narrow coastal strip, perhaps 10 meters max into open ocean. Swells and surges can happen in enclosed waters, but only on a scale of a few hundreds of meters.

If you think differently, you can start your own thread and explain your reasoning there.

27
Arctic sea ice / Re: "Stupid" Questions :o
« on: March 29, 2020, 03:14:40 PM »
I don't think we'll ever get back to "the same old". Every year we lose a little more volume, and this year we'll lose a lot more... A BOE will definitely change things forever...
So are you making an inane comment about the self-evidence of nothing ever staying the same? My "same old" was obviously referring to particulate pollution and contrails, which will be back to same levels as before when the current pandemic has run it's course.

And am I reading you correctly in saying that you are predicting "a lot more" loss of volume this year than normal?

Quote
Let's not do the SARS2 discussion here. Many people think that this crisis will end soon. Few know that this is only just the beginning. Nations will soon start to collapse, food production will become even more jeopardized, and selfishness will reign once more as nations fend for themselves...

covid-19 is relevant if people think it will have an effect on the comming melting season. But ridiculously apocalyptic doomsayings have no place in this forum.

[/quote]

28
Arctic sea ice / Re: The 2020 melting season
« on: March 29, 2020, 03:05:11 PM »

"Fram export is not in any way different this winter from other winters, judging by Wipneus' charts."  Concerning Wipneus' charts.  The Info that he provides is of immense value, however, a visual comparison between this year and last shows quite a difference.

No it doesn't.

There is slghtly more extent and more area and the last couple of months have seen slightly more voluminous export, but nothing to shout about and nothing out of the ordinary and it wil not effect this coming melting season in any way.

29
Arctic sea ice / Re: The 2020 melting season
« on: March 29, 2020, 03:00:36 PM »
We all know low arctic sea ice area will weaken the North Atlantic current.

I didn't. Do you have any supportive evidence for this claim? Or any of the below:

Quote
The large sea ice area in Atlantic Ocean will accelerate the ocean current exchange because more salinity and cold temperature. The momentum of ocean current will be helpful in melting the summer arctic sea ice. Together with  the high pressure and temperature in mid latitude will help to form cyclones in North Atlantic arctic region. All these will push more ice from CAB to Barrent Sea and Greenland Sea which will amplify the AMOC current.

30
Arctic sea ice / Re: "Stupid" Questions :o
« on: March 29, 2020, 02:57:42 PM »
Tom, if I understand you correctly, then I would agree that the effexts of particulate pollution are mostly localized and therefore mostly over land. Contrails are presumably also mostly found over land. And to take the thought further, increased insolation over land has a smaller warming effect than over water.

Blumenkraft, I would be surprised if changes in particulate pollution over industrial area would effect lightning strikes over the Siberian tundra - if there's an effet, it's probably very small.

31
Arctic sea ice / Re: "Stupid" Questions :o
« on: March 29, 2020, 01:15:59 PM »
As far as this melting season goes, particulate drop is a second order forcing.
Maybe third order.
Combine less particles with the effect of fewer contrails, and you've got a recipe for disaster IMHO. You can just feel the spring sun shining a lot harder right now here in Belgium. The sky is so clear. And the days are only getting longer...

If the current lock-down conditions continue into summer (which seems to be the most likely scenario) then it will most definitely have an effect, and probably a significant effect. But next year we'll be back to the same old.

However, everybody is very much aware of the huge economic costs this is having. People will start to starve to death in less developed countries (such as the USA) unless the lockdown is lifted. I'll predict that within a couple of weeks, some drug coctail or another will be shown to keep covid-19 symtoms to a manageable level in thos most affected, leading to a rapid slackening of limits on movement.

Another realisation is that at least half the population show no symptoms whatsover, and another quarter hardly any at all. Given that the "official" numbers are understating the real spread by at least a factor of 10, New York probably already has between a half and one million cases, with a doubling every few days. Saturation by the end of the week?

32
Arctic sea ice / Re: "Stupid" Questions :o
« on: March 29, 2020, 04:32:46 AM »
is the reduction in dimming agents playing a significant part?

Absolutely not. What we are seeing at the moment is not even a "melting event". Freezing has stalled but the drop in extent is mostly caused by wind-driven compaction of ice in the peripheral seas on the Pacific side (almost all in the Bering sea).

Other seas are mostly unchanged or "on time" for their annual reduction in extent. There is a drop in extent in the Barents but nothing unusual, and the Okhotsk (which, given it's latitude is probably the only sea experiencing any real melt-driven drop in extent) is only a week or so ahead of other high-extension years in that sea.

Having said that, it should not be unrealistic to expect that the drop in particulate pollution over the most densely habitated areas of the world will lead to som increases in global temperatures above what would otherwise have happened. Timing is also important, the drop in pollution in China happened quite early in the year and if they truly are over the worst of the epidemic, polluton levels will soon get back to normal, and China is undoubtedly the area most affected by particulate cooling in a normal year.

But the first effects of any drop in particulate pollution are going to be local. Trying to find any causal effect between drops in particulate pollution over China and slightly faster melt in the Okhotsk (for example) would be pretty near impossible, any effect being so tiny at this time that it is easily swamped by random changes in weather.

33
Arctic sea ice / Re: The 2020 melting season
« on: March 28, 2020, 02:13:05 PM »
Sounds reasonable if we are talking Fram Export - but why the "relatively warm waters of the eastern GS"?  Where you have floating ice in the Greenland Sea, the surface is at the melting point (-1.8C) and going outside of the ice covered areas, the temps are not really any higher, and nowhere above 0C.

However, looking at the ice edge all the way down from Svalbard to well south of Iceland, rapid melt is obviously ongoing, judginng by the aptly mis-named "froth".

Not that there is anything unusual about this situation, Fram export is not in any way different this winter from other winters, judging by Wipneus' charts.

34
Arctic sea ice / Re: The 2020 melting season
« on: March 28, 2020, 01:50:23 PM »
I'm a bit mystified by the GS mentioned in a few posts above. Is it meant to be short for the Gulf Stream? Doesn't really make sense to me, e.g. "the relatively arm waters of the eastern GS" - where is that?

35
Arctic sea ice / Re: The 2020 melting season
« on: March 24, 2020, 07:14:26 AM »
... I also don't like all the yellow I'm seeing in this graphic.  That concentration is a lot lower than I'd like.

Truly surprising the amount of less-than-full concentration in the Arctic itself.

36
Arctic sea ice / Re: The 2020 melting season
« on: March 16, 2020, 05:59:33 PM »
Binntho,

Please try to goggle "1947 record-breaking" and see what comes up. Europe was record-warm mainly during the summer and North America had record-Breaking snowfall in December. Many more 1947 records were beaten during the last few years, so maybe the Arctic was weird too, although few measurements were taken just after WW II.

Really. How interesting. I thought perhaps 1947 broke the record of not having broken any records. But the reliability of the "previous estimates" is rapidly clarifying.

37
Arctic sea ice / Re: The 2020 melting season
« on: March 16, 2020, 03:10:47 PM »
Binntho:
 
Quote
What previous estimates?

That would be my own estimates in a debate some years ago with a fellow discussant on this site.

Good to know.

Quote
You have yourself delivered a splendid example of a record year (1947) when the Greenland sea in April was nearly full of Arctic sea ice: https://www.pmel.noaa.gov/rediscover/datalist/phpFileTree/dmi_sea_ice_maps/1947/1947.pdf

I wasn't aware that 1947 was a record year ... what records did it break?

38
Arctic sea ice / Re: The 2020 melting season
« on: March 16, 2020, 03:05:40 PM »
Perhaps not the area at the link, but there is indeed less snow at the European side. This is taken from Nico Sun's website. Red areas on the map means less snow.

All the red areas are far to the south of the Arctic, and unlikely to influence temperatures there. But it would not surprise me if parts of Siberia had less snow than usual, the temps there have been extremely high this winter.

But if less snow is to make any difference, then there has to be significant difference in insolation in the Arctic itself. This is not happening yet, but remains one of the things to look out for.

39
Arctic sea ice / Re: The 2020 melting season
« on: March 16, 2020, 02:15:02 PM »
Snow is disappearing rapidly...

https://go.nasa.gov/38RadpN

I'm not seeing any real difference between now and previous years. Easy to scroll between the years for comparison.

40
Arctic sea ice / Re: The 2020 melting season
« on: March 16, 2020, 11:49:43 AM »
PA, no precedent.

But, previous estimates were that prior to the first BOE in the Arctic, the Greenland Sea ice extent would hit one million square kms.

Let's see if we get there this year...

What previous estimates?

41
Arctic sea ice / Re: The 2020 melting season
« on: March 16, 2020, 11:48:46 AM »
Also big... assuming it does reduce consumption, will be a reduction in SO2, which we know produces an increase at energy arriving at sea level.

So I assume you are saying that a decrease in SO2 causes an increase in energy reaching the surface? My first reading of this sentence implied the opposite ...

42
Arctic sea ice / Re: MOSAiC news
« on: March 03, 2020, 06:25:39 AM »
"Dropped anchor" ... how deep is the ocean at the Mosaic site? Four thousand meters?

43
Arctic sea ice / Re: The 2019/2020 freezing season
« on: March 02, 2020, 12:13:11 PM »
Brilliant!

44
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.”

45
Arctic sea ice / Re: "Stupid" Questions :o
« on: February 16, 2020, 06:05:42 PM »
Now that we are near the end of freezing season, I've noticed there are huge swings in daily extent gains, and even losses. Why is the behaviour of sea ice extent so wildly inconsistent around this time of year?

Why would you expect it to be stable? The ice can at this moment only expand into open ocean, where currents and contrary winds can and will cause large fluctuations. By far the biggest difference in extent from one day to another, and indeed from one year to another, during these winter months, is due to the vagaries of winds and have little or nothing to do with temperatures.

46
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!

47
Arctic sea ice / Re: "Stupid" Questions :o
« on: February 10, 2020, 09:05:08 AM »
I wonder if there is any limit to the stupidity, I guess not. The Internet is simply bristling with information, here is what the World Health Organisation has to say about receiving packages from China:

Quote
Yes, it is safe. People receiving packages from China are not at risk of contracting the new coronavirus. From previous analysis, we know coronaviruses do not survive long on objects, such as letters or packages.

48
Arctic sea ice / Re: "Stupid" Questions :o
« on: February 09, 2020, 06:28:24 PM »
If the Corona virus can survive for 9 days. And you order something on-line. And lets say that somebody sniezes on your stuff just before they ship it. It will be anywhere in half a day. Would it be able to survive the conditions in a airplaine ?

Well, I'd give it a try if you're really that curious. Order some used facemasks from the Wuhan hospital and breath through them while sleeping, and see what happens.

49
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.

50
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.

Pages: [1] 2 3 ... 24