The Arctic Shuffle

It’s odd where inspiration comes from sometimes.

I’d been watching this video of Tiny Tim singing “The Ice Caps Are Melting” and got to wondering where he got that idea back in the 1960s during the New Little Ice Age scare. Turns out, the Arctic Ice Cap has had periods of shrinkage at a variety of times (including when various US and Russian Subs surfaced and hung out at the North Pole in clear water). The video is a bit of a ‘hoot’ in any case:

Featured on this site

While I didn’t find his motivation, I did find some other interesting things. Like this nice page that talks about how truly horrific the winds are in Antarctica:

Wind is the movement of air from areas of higher pressure to areas of lower pressure. These pressure differences are caused by differences in temperatures. Generally, colder temperatures develop higher pressure due to the sinking of cold, dense air towards the Earth’s surface. Lower pressure is due to warm air rising from the surface of the Earth. The rotation of the Earth causes these winds to curve as they move from an area of higher pressure to an area of lower pressure.

In Antarctica, the wind patterns observed are part of a larger, global pattern of atmospheric circulation. Due to the round outline of the Antarctic continent, the circulation is relatively uniform with few irregularities to complicate weather patterns.Thus, the continent is ringed by a series of weather “bands”, each of which has its own particular weather conditions.

It then proceeds to describe those different bands. Having that kind of thing change it’s range could really mess up your day!

Inversion Winds
Some of the fiercest and most deadly Antarctic winds are created by temperature inversions on the high interior ice plateau. The Polar Plateau offers a constant source of extremely cold air which settles close to the ground due to the force of gravity. This pool of dense air flows from the high continental interior down toward the coast, just like a river. The Coriolis effect deflects these inversion winds toward the west, creating the coastal easterlies.

Katabatic Winds
Most of the interior surface winds move over a gentle slope. However, indentations and channels in the landscape can force the airflow to converge, like placing a finger partway over a flowing water hose. This strengthening and intensifying effect on air flow creates what are called katabatic winds (katabasis is Greek for descent). Katabatic winds begin as inversion winds. Like inversion winds, they are gravity-driven but they flow down the much steeper slopes of the coastal regions. The winds are surface winds, only reaching heights of about 1500 feet, although this height varies. Wind speeds can accelerate suddenly from quiet conditions to 60 feet per second (40 mph).

The most famous site for Katabatic Winds, and the windiest spot on Earth, is Cape Dennison at Commonwealth Bay. Convergent katabatic flow from the East Antarctic Ice Sheet results in a mean annual wind speed of 50 miles per hour (80 kilometers per hour)!

Golly. MEAN of 50 MPH so it’s a lot faster a lot of the time…

The Science

So, along the way, I run into this excellent paper by Joe D’Aleo and George Taylor:

By Joseph D’Aleo CCM and George Taylor CCM

That points at the AO and AMO as key driving factors. Well, we looked at the AMO just a while ago, but this AO graph is particularly striking. Taken along with the now very cold state of the AMO, I would expect that well find glacier growth picking up again and building Arctic Ice Cap volume and extent over time as the oceans cool up north(they lag several years).

It looks like it dates from about 2007, so perhaps an update will be made sometime soon showing the impact of the present swap to very cold AO and AMO.

Arctic Oscillation Jan 2011

Arctic Oscillation Jan 2011

AO Graph Source

Now that is Quite A Plunge at the end! The graphs in Joe’s paper are from before the AMO and AO fell off a cliff.

An Alternative AO Graph Source as found on:

Here’s the AMO for comparison:

North Atlantic Oscillation upload Jan 2011 data ends November 2010

North Atlantic Oscillation upload Jan 2011 data ends November 2010

NAO Graph Source

Both of these are in a very cold state. This, in keeping with my reading of the D’Aleo paper, means more glacier growth and more Arctic Ice Cap growth in our future.

And what’s happening with the Polar Vortex? Well, it’s running at or beyond the decade average MAX area:

Polar Vortex

Polar Vortex

Original Source

The area of Arctic Air has gotten larger. Much larger. And it’s got a more ‘loopy jet stream’ to spread it around into North America, Europe, and Asia. That will make more ice, more snow, more glacial growth, and more ice cap growth.

An Ozone Connection?

Interesting to note that the “Ozone Hole” (that is actually just a thinning) is also shrinking:

South Pole Ozone "Hole" plot

South Pole Ozone "Hole" plot

Something is afoot with Ozone and it’s NOT due to CFC gas emissions changing. Things are changing way too fast for that.

Original Image from this site:

They also have this interesting UV chart that I’m gratuitously including just because I need to watch my UV exposure and I think it’s a ‘way cool’ chart:

World UV dosage 'live chart'

World UV dosage 'live chart'

Who Needs An Arctic Ice Cap, Anyway

I also stumbled on this plan from the Russians to deliberately melt the Arctic Ice Cap. P.M. Borisov suggested it woud be a good thing. Several other such melting plans are also listed:

This material presents the plan of Petr Mikhailovich Borisov for melting the Arctic ice cap. If the Arctic ice is once melted much less of the sun’s radiation will be reflected out into space and therefore the arctic ice cap will not re-form. An ice-free Arctic Ocean would be a great boon to oceanic shipping, especially between Europe and East Asia. Much land in northern Canada and Siberia would be freed of permafrost and made suitable for agriculture. Borisov believed that an ice-free Arctic Ocean would lead to increased evaporation of water and hence increased rainfall worldwide, including the region of Sahara Desert leading to grass growing there. Borisov considers all of the impacts of the melting of the Arctic ice cap to be beneficial. He asserts that the melting of the Greenland ice cap would raise sea levels at a rate of only 1.5 to 2 mm per year.

Soviet climatologists in the 1950’s and 60’s gave considerable thought to how the melting of the Arctic ice cap could be achieved. Two conferences were held on the topic in Leningrad in the early 1960’s after an initial conference was convened in Moscow by the Presidium of the USSR Academy of Sciences in 1959 on the topic.

The idea of melting the Arctic ice cap goes back at to 1877 when Harvard geologist Nathaniel Shaler proposed channeling more of the warm Kuroshio Current through the Bering Strait. Carroll Livingston Riker in 1912 proposed using a 200 mile jetty off Newfoundland to divert more of the Gulf Stream to the Arctic Basin. Julian Huxley while he was head of UNESCO proposed, in 1946, to use nuclear weapons to break up the Arctic ice cap. Borisov in his article lists the more recently suggested methods for melting the Arctic ice cap.

More at the link…

That article talks about the source as being the Bulletin of the Atomic Scientists, which lead to some Google time, that lead to this article in Google Books where it looks like some other nuclear scientists were proposing that they take nuclear waste, make it into nice little hot vitreous rocks, set it in the middle of Antarctica and let it melt it’s way down to bedrock as a form of self entombment. (I wonder if anyone pointed out that they would still be hot at the bottom and that melting and mixing with hot water was generally “a bad thing” for keeping stuff from wandering off… )

And folks wonder why I don’t trust THIS crop of “experts” any more than I trusted the LAST crop…

Some Speculation

Then there is this little article that seems to think that the change in solar output especially in the UV band has caused our atmospheric shrinkage (that one would speculate then leads to things like expanded vortex paths and changes in AO / AMO / etc.):

I was just going to quote some teasers from it, but they have it ‘tagged’ in such a way that you can’t just ‘mark text and copy’ more than tiny bits; so instead I guess I’ll reproduce the whole thing here. That way if I want to quote bits of it in the future I won’t have to go through the fancier techniques…

Shrinking atmospheric layer linked to low levels of solar radiation
AGU Release No. 10–28
26 August 2010
For Immediate Release

WASHINGTON—Large changes in the Sun’s energy output may cause Earth’s outer atmosphere to contract, new research indicates. A study published today by the American Geophysical Union links a recent, temporary shrinking of a high atmospheric layer with a sharp drop in the Sun’s ultraviolet radiation levels.

The research indicates that the Sun’s magnetic cycle, which produces differing numbers of sunspots over an approximately 11-year cycle, may vary more than previously thought.

“Our work demonstrates that the solar cycle not only varies on the typical 11-year time scale, but also can vary from one solar minimum to another,” says lead author Stanley Solomon, a scientist at the National Center for Atmospheric Research’s High Altitude Observatory. “All solar minima are not equal.” Researchers from the University of Colorado at Boulder (CU) also contributed to the project.

The findings may have implications for orbiting satellites, as well as for the International Space Station. The fact that the layer in the upper atmosphere known as the thermosphere is shrunken and less dense means that satellites can more easily maintain their orbits. But it also indicates that space debris and other objects that pose hazards may persist longer in the thermosphere.

“With lower thermospheric density, our satellites will have a longer life in orbit,” says CU professor Thomas Woods, a co-author. “This is good news for those satellites that are actually operating, but it is also bad because of the thousands of non-operating objects remaining in space that could potentially have collisions with our working satellites.”

The Sun’s energy output declined to unusually low levels from 2007 to 2009, a particularly prolonged solar minimum during which there were virtually no sunspots or solar storms. During that same period of low solar activity, Earth’s thermosphere shrank more than at any time in the 43-year era of space exploration.

The thermosphere, which ranges in altitude from about 90 to 500 kilometers (55 to more than 300 miles), is a rarified layer of gas at the edge of space where the Sun’s radiation first makes contact with Earth’s atmosphere. It typically cools and becomes less dense during low solar activity. But the magnitude of the density change during the recent solar minimum appeared to be about 30 percent greater than would have been expected by low solar activity.

The study team used computer modeling to analyze two possible factors implicated in the mystery of the shrinking thermosphere. They simulated both the impacts of solar output and the role of carbon dioxide, a potent greenhouse gas that, according to past estimates, is reducing the density of the outer atmosphere by about 2 percent to 5 percent per decade.

Their work built on several recent studies. Earlier this year, a team of scientists from the Naval Research Laboratory and George Mason University, measuring changes in satellite drag, estimated that the density of the thermosphere declined from 2007–2009 to about 30 percent less than that observed during the previous solar minimum in 1996. Other studies by scientists at the University of Southern California and CU, using measurements from sub-orbital rocket flights and space-based instruments, have estimated that levels of extreme-ultraviolet radiation—a class of photons with extremely short wavelengths—dropped about 15 percent during the same period.

However, scientists remained uncertain whether the decline in extreme-ultraviolet radiation would be sufficient to have such a dramatic impact on the thermosphere, even when combined with the effects of carbon dioxide.

To answer this question, Solomon and his colleagues used a computer model to simulate how the Sun’s output during 1996 and 2008 would affect the temperature and density of the thermosphere. They also created two simulations of thermospheric conditions in 2008—one with a level that approximated actual carbon dioxide emissions and one with a fixed, lower level.

The results showed the thermosphere cooling in 2008 by 41 kelvins (about 74 degrees Fahrenheit) compared to 1996, with just 2 K attributable to the carbon dioxide increase. The results also showed the thermosphere’s density decreasing by 31 percent, with just 3 percent attributable to carbon dioxide. The results closely approximated the 30 percent reduction in density indicated by measurements of satellite drag.

“It is now clear that the record low temperature and density were primarily caused by unusually low levels of solar radiation at the extreme-ultraviolet level,” Solomon says.

Woods says the research indicates that the Sun could be going through a period of relatively low activity, similar to periods in the early 19th and 20th centuries. This could mean that solar output may remain at a low level for the near future.

“If it is indeed similar to certain patterns in the past, then we expect to have low solar cycles for the next 10 to 30 years,” Woods says.

The study, published in Geophysical Research Letters, was funded by NASA and by the National Science Foundation.

They include directions for getting a copy of the whole paper should you wish.

OK, so by actually looking at stuff (satellites in this case) they find out “the sun did it” and “It’s the UV not the CO2, stupid”.

Somehow I trust Navy guys who have to keep things up and working more than I trust Hansen, Peterson, and the CRU Crew…

In Conclusion

It’s cold. It’s getting colder. It will continue to get A Whole Lot Colder. The drivers are pretty clear at this point, ant the mechanisms are being laid out as well. CO2 has very little say in the whole thing, and more folks are starting to realize that.

A partial list of them is here:

And as a final foot note:

I recently got a call from a friend in Ecuador. Seems there is snow on the mountains, in quantity, and at lower elevations than anyone can remember…. That thinner colder atmosphere is even being felt on the equator… Nothing like a few direct physical observations to point you in the right direction…

For those interested in another little trip to the past, this TIME article from 1974 describes the change in the polar vortex and how it was making for the New Little Ice Age we were all expecting back then. Sounds almost like they are describing now:,9171,944914,00.html

It is also interesting to see how much snow is out there right now. It’s rather a lot:

Current Ice and Snow in the Northern Hemisphere 2 January 2010

Current Ice and Snow in the Northern Hemisphere 2 January 2010

Orginal Image Source

Subscribe to feed


About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
This entry was posted in AGW Science and Background and tagged , , , . Bookmark the permalink.

19 Responses to The Arctic Shuffle

  1. Baa Humbug says:

    I like the fact that data by/from the satellite blokes can’t/won’t be fudged, i.e. out of the cabals reach.

    Inigo Owen Jones predicted the change in climate in 2010 way back over 60 years ago.

  2. ES says:

    There are places in the Antarctica where the wind blows off the plateaus and it forms what is known as blue ice. On these surfaces, called blue-ice runways, you can land a large wheel equipped aircraft instead of having to use skiis. Where this picture is taken the ice is more than 1000 meters thick:

  3. Laurence M. Sheehan, PE says:

    Pity it is that the weather entertainers speak of apparent visual effects, equivalent to “sunrise” and “sunset” instead of relatively easy to explain physics and chemistry. The more difficult to understand fluid dynamics has a part also.

    The planet rotating on its axis, viscosity of air, atmospheric inertia, varying coefficients of friction between surface and atmosphere, density of air under different pressures, temperatures and humidity conditions.

    My high school physics teacher was a fine teacher. Somehow, most students could understand his explanation from a physics standpoint on what causes the winds to seem to “blow”. Took a blackboard to draw diagrams.

    A good many farmers’ teens in the class, and thus a relevant interest in what causes differences in weather and winds.

  4. Tony Hansen says:

    Baa, do you have a link to Inigos stuff?
    I went looking some time back with no luck.
    One of the oldtimers around here showed me a newspaper clipping in about 1990 (carefully kept for decades) in which Inigo correctly predicted, as it turned out, the dry spell in the early 1990’s.
    Not bad for a bloke who died in 1954.

  5. Maxwell says:

    My understanding is that if the outer layers cooled, due say to greenhouse gas increase, then the surface temperature must rise to maintain radiation equilibrium. I thought this was standard GH theory.
    Now it’s being said that the cooling by the lowering of solar UV emissions is far greater than that produced by increased CO2. If this is so then the surface temperature must increase a lot more. Why aren’t we seeing that yet or are we?

  6. E.M.Smith says:


    As near as I can tell, trying to make the “Warmers” radiation driven model make sense of things doesn’t work and just leaves you (and me) confused.

    If you toss it out and look at the world as driven by (the very visible) convection process we see in the weather of the world, it all makes a lot more sense.

    Then if you have colder air “up high” a convection cell will hit more cold sooner and dump it’s heat. Then very cold rain and snow falls to the ground. You effectively moved more heat off the earth and up into very cold air. That then radiates off into space. End of story.

    Less UV, thinner air, colder up top, more convective heat flow.

    Trying to use the “standard GH theory” will just lead to no good… It gives you paradoxes where cooling air has to make you warmer… The convective model just says “hot air rises” and it rises faster if the cold air that is sinking back is even colder…

    So a warm equatorial zone has air rise, And cold polar zones have cold air sink ( I’m leaving out one rise / fall zone in the middle for simplicity). With very cold upper air, the cold air sinking at the poles is much colder, and we get more polar area covered by the Polar Vortex and it spits more of the cold air out further. Thus cold weather and more snow.

    Simple, really. Just drop all the GH nonesense and it flows.

    The lack of a UV heated hot blanket on top means the air down here can get colder, and it does. (As another simple way to see what’s happening).

    Hope that helps.

  7. Verity Jones says:

    Great post – you’ve pulled together a lot of really interesting stuff here. For example I was aware of the Polar vortex area thing and Stephen Wilde’s theories about it, but that graph, well – wow!

    Also I hadn’t taken the time to read Pierre Gosselin’s collection of cooling predictions on NoTricksZone.

    I would say the evidence of cooling is mounting before our eyes and yet somehow [;-0] the analysis of the instrumental record is blind to it.

  8. Pascvaks says:

    As the Arctic cools the Antarctic should warm.
    BUT, if as the Arctic cools the Antarctic gets colder,
    We gonna’ be in a mighty cold pickle barrel.

    Remember, life’s a beach!
    Sometimes even oceans freeze.

  9. David says:

    “The Science
    So, along the way, I run into this excellent paper by Joe D’Aleo and George Taylor:

    By Joseph D’Aleo CCM and George Taylor CCM

    Click to access GLACIERSANDICECAPS.pdf

    That points at the AO and AMO as key driving factors. Well, we looked at the AMO just a while ago, but this AO graph is particularly striking. Taken along with the now very cold state of the AMO, I would expect that well find glacier growth picking up again and building Arctic Ice Cap volume and extent over time as the oceans cool up north(they lag several years).”

    It may not be lagging that much.

  10. Verity Jones says:

    Isn’t it interesting that one set of scientists can propose artificial melting of the icecap to benefit their countries (presumably with a focus on economics) saying that destroying it means it would never reform to the same extent, yet quite another set (with a focus on environmental) issues dire predictions of the effect on Earth when it happens naturally (of course they don’t see it as natural).

    Both sets talk about the effect of the summer solar radiation heating up the Arctic ocean such that the ice would be slower to reform and would be thinner, then easier to melt the next year etc. etc. But life’s just not that simple. Aside from a veil of volcanic dust or a couple of cloudier summers than usual, in the natural cyclic variations in climate, warmer waters forming in the tropics are transported poleward melt ice from underneath the icecap*.

    Now just what is the balance between these two melt mechanisms? Which would win out? I’m pretty certain that the latter is the driving force in the gross ice extent fluctuations that we’ve seen over the last century. Of course what drives that? Again, pretty sure it’s the sun but it is the detail of how that we all continue to debate.

    *OK I left out winds, again weather driven and very pertinent to the AO and polar vortex changes. These scientists have been ‘stuck on’ the AO remaining positive or tending to be more positive due to global warming. So with an AO tending to be more negative, that would tend to keep ice at the pole instead of pushing it down the Greenland coast. I wonder, I just wonder, if we had gone down the articifial route, how long man could have managed to keep the Arctic ice free.

  11. David says:

    Regarding your WUWT post here…E.M.Smith says:
    January 3, 2011 at 4:15 am

    Leif is a good skeptic, yet demands proof of what is admitted conjecture. Mosh demands all numbers now for processes science is just beginning to understand.

    Your post showed one of many observed effects of sublte energies that may well affect not only cloud formation but cloud location or latitude. Whatever the cause of the AO, if it moves jet streams and storm tracks further south it reduces SWR entering the oceans. The atmosphere is forever chasing and failing to catch the ocean temperatures. If the oceans do cool, then the atmosphere will follow. In a 70% water planet SWR rules, it just takes time to manifest.

    BTW Leif and Mosher are far more educated then I. I just think they (and all of us in regard to climate) are like the blind brothers describing the elephant, each brother touching a different part claims his version is correct.

  12. Malaga View says:

    @ David January 3, 2011 at 4:44 am

    Old Age advice: Beware of Greeks bearing gifts

    New Age advice: Beware of Greeks demanding proof

    From my perspective Science is never Settled it just has not been disproved yet…

    @ E.M.Smith January 3, 2011 at 2:20 am
    Simple, really. Just drop all the GH nonesense and it flows.

    Makes sense to me… which seems to confirm my view that Climate Science, as practised by The Team, is an oxymoron… and that Weather is Climate


    Definately not a GREEK as you speak my language… more an HONEST BROKER that keeps on giving… that keeps on observing… that keeps on thinking… long may it last!

    Happy New Year!

  13. Pascvaks says:

    Ref – David on January 3, 2011 at 4:44 am
    …”I just think they (and all of us in regard to climate) are like the blind brothers describing the elephant, each brother touching a different part claims his version is correct.”

    Yes! And it’s funny, as time went by, just how right (in a way) each of them were regarding their own part of the puzzle. Well… considering what they knew and what they could see of course. That’s probably what we’re going to need, a lot more time to see the whole and not just the seperate parts with our very limited modern vision and tools. Funny how blind people can be without even trying. There must be something unique to human progress in all this. We know we’re blind. Most of our relatives don’t seem to know, or care. Let’s hope our next evolutionary change will be a step toward improvement in this regard and not one in another direction.

  14. @Pascvaks

    Then, something must be wrong…..Your know, “The devil is in the details”, why?, just because he wants us to get lost in them. We must return to the more general laws: To the operating “Symbols of the Sacred Science”…but how will we do it, if we are so conceited with entanglements: The more “difficult”, the more”dimensions” the more “intelligent” we are, the more “cool”. Thus we use a synchrotron of billions of dollars where Pythagoras used a Mono-chord and a triangle. :-)

  15. E.M.Smith says:

    So many good comments. And I can’t respond to all of them right now (pressing things to do…) I’ll have to be brief, but I’ve read every one.

    @Verity: Glad you liked it, yeah, record large polar vortex goes a long way to explaining your broken pipes …

    As I remember my Milankovitch, it’s the summer melt at the north pole that is critical. S.pole is always frozen, so has no causal impact. N.Pole winter is always cold enough to make ice. It’s the N.Pole summer that CAN melt, so does to some degree. And that’s a very good thing…. As soon as it does not melt during summer, we’re headed back to Ice Age 101…

    The folks cheering for summer arctic ice at record levels have no clue what they are asking for…

    But yeah, I think we could melt it all in the summer and it would have no impact. Winter would come, and ice starts again…


    Yeah, though I’ve established a ‘relationship’ of sorts with Leif where he accepts that I will flag things as ‘speculation’ and don’t need to be chastened that it’s not proven. Mosh still is too fascinated with the numbers. Does no good to put numbers on part of a process when the rest is a black hole of ignorance…. I like to paint the picture first, then give it a number, he likes to paint by numbers ;-)

    I assume you were talking about comments here:

    I need to add a note about that noctilucent cloud forming from UV impacts to the thread here, but for now this link will have to do…

    @Malaga View:

    That’s what I try to do. Find understanding and truth, put a light on it. Repeat. The hardest part is keeping the misdirection and frankly trash that’s pushed / published out of the brain…


    That’s why I always try to get the understanding first, then the rest can follow. I’ve written bad code and set it loose on a problem, to run for days, then went back and THOUGHT about my code some more. Took a few more hours to polish it. Get the ideas right and the approach cleaner. Then run it to completion in hours or minutes. Then waited a day or too for the “first code” to finish as a cross check on the results.

    Substantially every time it pays off to think more first, then code. Too fast a ‘run for the numbers’ and analysis leads to poor results, in my experience.

    Or as Dad used to say: Measure twice, cut once.

    On reflection, I also remember Dad saying “Don’t dig your post holes ’till you’ve laid out the wood”… after I discovered I’d put three post holes in with 9 feet between each set of two… and 8 foot stringers… Fill one post hole, dig two new ones… I’ve learned that going slower is often the fastest path.

    (Though I do still like to ‘rough plough’ and get some early idea where the good spots are in the field…)

  16. PhilJourdan says:

    One way to ensure the ice caps stay put is to try to melt them. The less that man knows, the more damage he does, and right now our knowledge about Global Climate would not fill a thimble.

  17. P.G. Sharrow says:

    While painting by the numbers sort of works. To really paint by the numbers you need to know how to paint. The numbers have to be correct and in the right places.

    In the old days of engineering design “If it did not look right, then it was not right” no matter what the numbers said. pg

  18. Jason Calley says:

    E.M. says: “The most famous site for Katabatic Winds, and the windiest spot on Earth, is Cape Dennison at Commonwealth Bay. Convergent katabatic flow from the East Antarctic Ice Sheet results in a mean annual wind speed of 50 miles per hour (80 kilometers per hour)!”

    There is a book, “Mawson’s Will” which details the story of the first expedition inland from Cape Dennison. The book is described as “the greatest polar survival story ever written.” It is. No, really. If the thought of 50 mph average wind speed at Antarctic temperatures does not impress you, read the book.

    By the way, E.M., re your “Dad used to say: Measure twice, cut once.” The version heard at my house was “Damn it! I’ve cut this board three times and it’s STILL too short!”

  19. David says:

    Jason Calley
    “By the way, E.M., re your “Dad used to say: Measure twice, cut once.” The version heard at my house was “Damn it! I’ve cut this board three times and it’s STILL too short!”

    Kind of like Lee Trevino, “In all my years of golf I have never had a short put go in the hole.”

Comments are closed.