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Messages - TenneyNaumer

Pages: [1] 2
1
Arctic sea ice / Re: The 2019 melting season
« on: April 10, 2019, 06:11:33 AM »
The Arctic Oscillation Index is now pretty negative, which used to mean that melting slowed (during March, April, and May), but it's still heading south.  But the polar jet is crazier than ever.  If the Index stays negative and the melt continues apace, we are truly in new territory. 

2
Arctic sea ice / Re: Latest PIOMAS update (May mid-monthly update)
« on: June 01, 2018, 09:20:53 PM »
so I'm not sure what Tenney's on about.

Glad I am not the only one.  I did wonder if we were just talking past each other.


How are you ruling out slow rate of decline now the MYI is down to minimal levels (and FYI replaces itself each winter) and some natural variability?

I am not taking your point, crandles.  I have been saying for many years that PIOMAS cannot be right, that the increases in volume from the low must be due to problems with the algorithms.  Of course, there might have been some increase due to natural variation, but the consistent increase over several years cannot have been right, IMO. Tell me how the water-logged slush can be measured in the same way that a similar section of tightly compressed multi-year ice can?  Further, slushy ice cannot be same temperature.  And, there is the stuff that resembles swiss cheese.  How is that being handled?

This seems based on assuming a rapid rate of decline and therefore does not appear to address the issue at hand of how to rule out slow rate of decline and some natural variability.

http://psc.apl.uw.edu/wordpress/wp-content/uploads/schweiger/ice_volume/BPIOMASIceVolumeAnomalyCurrentV2.1.png

3
Arctic sea ice / Re: Latest PIOMAS update (May mid-monthly update)
« on: May 30, 2018, 08:29:03 PM »
I do not agree that common sense would tell us that sea ice volume would go consistently up for 5 straight years when we know that the temperatures in the Arctic have also been going up.  Is it also common sense that PIOMAS shows the sea ice increasing over the past few months?  In any case, by the end of this summer, I think we'll have some answers.

http://psc.apl.uw.edu/wordpress/wp-content/uploads/schweiger/ice_volume/BPIOMASIceVolumeAnomalyCurrentV2.1.png

4
Arctic sea ice / Re: Latest PIOMAS update (May mid-monthly update)
« on: May 30, 2018, 05:04:00 AM »
Re: PIOMAS

The high volume for 2009 and 2015 are nearly the same on the graph.

Doesn't stand to reason.

How are you ruling out slow rate of decline now the MYI is down to minimal levels (and FYI replaces itself each winter) and some natural variability?

[Or does this sound like cognitive dissonance: I was expecting a crash and it hasn't happened but I don't want to change my views and admit the rapid Arctic ice free sceptics were right.]

I am not taking your point, crandles.  I have been saying for many years that PIOMAS cannot be right, that the increases in volume from the low must be due to problems with the algorithms.  Of course, there might have been some increase due to natural variation, but the consistent increase over several years cannot have been right, IMO. Tell me how the water-logged slush can be measured in the same way that a similar section of tightly compressed multi-year ice can?  Further, slushy ice cannot be same temperature.  And, there is the stuff that resembles swiss cheese.  How is that being handled?

5
Can anyone get a high-res shot of the calving fronts of Jakobshavn for April 10?  Appears to be something going on there, looking at EOSDIS (looks too big to be a cloud's shadow):

Thank you Tea Light, must be a cloud after all!

Did you mean the 9th April like your link? The dark blob is the shadow of a low cloud. A later date is not yet available.

6
Arctic sea ice / Re: Latest PIOMAS update (May mid-monthly update)
« on: May 27, 2018, 08:11:17 AM »
Re: PIOMAS

The high volume for 2009 and 2015 are nearly the same on the graph.

Doesn't stand to reason.

Further, ice in 2009 was fundamentally different from the slush of 2015. 

And...  the average temperature of the ice has to be much higher than it was 9 years ago. 

There is something way off in their algorithm and has been for years.

But I repeat myself.

8
Yeah, I think so, now, too. Must be visible now due to a further decrease in elevation in that area -- at least their persistence in the same shape and position would seem to indicate that.

Did Jakobshavn Isbrae undergo a wave from upstream, or what is going on?

I am thinking those waves are more a result of the underlying topography.

9
Did Jakobshavn Isbrae undergo a wave from upstream, or what is going on?


11
Sidd's the best!

12
That's such a great map.

You know where you have the -200 on the north edge of the south branch?

Looks like something might be going on there, perhaps, judging by today's NASA Worldview.

It would be the most vulnerable spot right now, wouldn't it?

13
Arctic sea ice / Re: The 2016/2017 freezing season
« on: January 09, 2017, 12:11:45 AM »
Tigertown, if you want to see the storms entering the Arctic, they can be seen here:

https://weather.gc.ca/data/satellite/hrpt_dfo_ir_100.jpg

14
Arctic sea ice / Re: The 2016/2017 freezing season
« on: January 07, 2017, 03:38:35 AM »
Meltwater runoff from the ice sheet itself is at the point of bypassing, or already has, glacier outflow in contributing to decreasing mass balance. That will only continue as the altitude of the ice sheet decreases and is exposed to warmer temperatures.  I don't believe the topography of Greenland is going to be much of a restraint on meltwater runoff.

15
Arctic sea ice / Re: The 2016/2017 freezing season
« on: December 25, 2016, 05:15:30 PM »
Bairgon, please could you tell me how you access these images?  Is there a page where one can pick the latest photos by location?

Thanks much!

Tenney

I believe the storm has made itself felt.

The leads at the head of Nares have collapsed indicating that the ice has not formed a rigid bridge between Greenland and Ellesmere.

Compare NOAA picture from 23rd Dec at http://ocean.dmi.dk/arctic/images/MODIS/Lincoln/201612231322.NOAA.jpg with the most recent clear picture from 19th Dec at http://ocean.dmi.dk/arctic/images/MODIS/Lincoln/201612191227.NOAA.jpg

The Sentinel 1 pictures of the straight show that export is still happening: 22nd Dec at http://ocean.dmi.dk/arctic/images/MODIS/Kennedy/20161222s01a.ASAR.jpg vs 23rd Dec at http://ocean.dmi.dk/arctic/images/MODIS/Kennedy/20161223s01a.ASAR.jpg shows movement down the channel, particularly on the northern side.

16
Thanks, Terry!

We know those ice shelves aren't coming back for eons -- it does make one feel a bit sad.

17
Thanks, Terry.  A nice discussion.  Unfortunately, many links now broken.  Is there evidence on how old the Ward Hunt remnant is?

19
Thanks for posting that photo, johnm33 -- perturbing. 

20
79N and Zachariae are endlessly fascinating.  I remember seeing Ian Joughlin's ice velocity map back in 2007 or so, and when I saw that the northeast ice stream went southwest hundreds of miles and the inclination was pretty steep, it really grabbed my attention. That map is here:  http://static.skepticalscience.com/pics/Figure6.jpg

Do we know if the velocity has increased since 2006 and by how much?

I also have to admit I like the shapes of the calving fronts. 

The other thing is that there used to be an enormous land-fast ice shelf right there that buttressed these glaciers.  I remember it breaking up pretty dramatically in July 2007.  I suppose it probably did that in earlier years, but I was not paying any attention before the winter of 2006-07.  Remember when the sea ice would flow out all down the eastern coast of Greenland? 

21
I think I should have phrased my question about the calving front differently.

I'm pretty interested in how much area has been gobbled up along the north wall of the south branch -- JI is far wider, now, isn't it? 

And the same is true of the north branch -- it used to be very noticeably narrower than the south branch. 

22
How far has the calving front of the southern branch retreated since this time last year?

23
Uh, do I need the download with binaries or without?  What do they do?

24
Thank you so much, sidd!

25
I did download SNAP and it seems to work, insofar as it let's download .jp2 images that I cannot open.  I have heard there are apps for that, but really haven't wanted to experiment by downloading any of them because I don't want to download possible threats to my laptop.

I don't need to manipulate the photos, and I don't care if they are really large files.  I just want to look at the details.

Oh, I guess I should say that I really hate Win10's photo viewer, so am very open to replacing it with something better. 

My needs are simple.  I used to do everything I wanted with the Office Suite accessory Picture Manager.  'course Microsnot thinks better, and got rid of it.

26
I've got a Dell laptop with a 4K screen, 16 Gb and a Core i7 processor.  Seems adequate, no?

I've wanted to get a Mac for years but still can't afford one.

I might try to finance a Mac around Black Friday in November, so I guess I just have to wait to see these images.




27
Extreme neophyte that I am, I don't know how to open a .jp2 file.  Any hints would be appreciated!

28
I keep trying to figure out how to download WEB22 images via ESA SNAP, but I still don't have a clue how to work the thing, so I will just point out that the melt ponds mostly up and drained today, and it appears that something has gone on north and to the west of the calving front of the south branch, as in it looks like there was a lot of movement, such that even that dirty line coming out of the north branch was diverted. 

(And, btw, what is that dirty line, anyway?  It is so persistent, one could even speculate that it was an oil slick.  How can it be coming out black (or dark) like that for so long?  Maybe y'all have already discussed this somewhere, but I missed it.)

29
Somebody please tell me there is something wrong with this image
http://ocean.dmi.dk/arctic/images/MODIS/Disko/20160615s01a.ASAR.jpg

30
Sure wish there was a high res sentinel image of what is going on down the south branch:

http://ocean.dmi.dk/arctic/images/MODIS/Disko/20160604s01a.ASAR.jpg

31
So, solartim, did that calving front at the south branch move back to a new record?

I don't think anything big happened at the north branch -- looks like clouds.

32
Those are some images of incredible melting for this time of year, A-Team!

Wish I knew how to do what you do!

Thanks for doing it for us!

33
Never mind.  The depressions are the remnants of melt lakes from last year.

34
Sorry, I don't have access to high-res photos, but wanted to point to the two rather large depressions to the east of Jakobshavn (which can be seen in photo above) -- might this have been collapse of firn?

35
Arctic sea ice / Re: Latest PIOMAS update (March)
« on: March 13, 2016, 05:26:36 PM »
Instead of focusing on models, you should be focusing on the actual sea ice.  It is not solid -- it is full of large holes like swiss cheese.  The ice now is nothing like it was in 2012. 

We've been getting plenty of information that it is soft like butter.  It used to be very solid and hard.

It is simply not the same animal. 

36
Arctic sea ice / Re: The 2015/2016 freezing season
« on: March 13, 2016, 05:21:43 PM »
Here is a perfect example of what happens when the Arctic Oscillation Index goes positive -- we're going to see some big melt on the Atlantic side as the warm air pushes into the Arctic:

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao_index.html

You can see it going in here:

http://mp1.met.psu.edu/~fxg1/SAT_NHEM/animw.html

37
Arctic sea ice / Re: The 2015/2016 freezing season
« on: March 06, 2016, 06:07:46 AM »
Sure, heat heads toward the Arctic directly from the Equator via the water vapor streams.

In 2006, the year after Katrina, there were many hurricanes in the Atlantic and typhoons in the Pacific.  However, very few were land-falling.  Most ran into the water vapor streams along the east coast of Asia and the east coast of North America and were sucked up and most of their energy went directly to the Arctic via the Bering Strait and the North Atlantic.  It seemed to me that the big melt in 2007 was partly the result of this "priming."

Interestingly, we've had some early rapid melting (usually in May) for the past few years.  Note that the Arctic Oscillation Index has been positive at these times.  Then, when the Index goes negative, the water vapor is deflected away from the Arctic in the North Atlantic, and the melt lessens or the ice may even grow. 

You can see that right now:

http://mp1.met.psu.edu/~fxg1/SAT_NHEM/animwjap.html

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao_index.html

38
Arctic sea ice / Re: The 2015/2016 freezing season
« on: March 05, 2016, 07:14:23 AM »
So back to topic - yes, the lack of export of heat out of the Arctic this winter is very alarming, and may in fact be a state change signal.  Interestingly, I don't think that state change is in the Arctic itself, but rather is in global heat circulation and the disintegration of discrete cellular circulation in the atmosphere (Hadley Cells, Ferrel Cells, Arctic Cells).  Long term, decreased ice will cause that particular signal to amplify, and perhaps add a new "limb" to our "pendulum".

I have been very interested in the changes in the atmospheric circulation in the NH, particularly since the end of 2010. 

I've sort of addicted to watching the animations of water vapor via:

http://www.ssec.wisc.edu/data/geo/index.php?satellite=west&channel=wv&coverage=fd&file=gif&imgoranim=8&anim_method=flash

and http://www.ssec.wisc.edu/data/geo/index.php?satellite=coms&channel=wv&coverage=fd&file=gif&imgoranim=8&anim_method=flash

There used to be 5 to 7 distinct "streams" heading from the Equator to the Pole, going from the southwest toward the northeast

There was a noticeable, albeit small, change in late 2010, that grew ever larger with the passage of time, until now you can easily see that there are only 3 main "streams" (very broad ones), and they flow toward the east, and much less toward the northeast.

You can observe this better here:

http://mp1.met.psu.edu/~fxg1/SAT_NHEM/animwjap.html

The circulation in the Southern Hemisphere has also begun to go off its "normal" rails, but since Antarctica is huge and can maintain its cold much better, the effect nowhere nearly as extreme as what is going on in the north.

jdallen, you are the first person I have seen mention this.  Surely there are some articles about it by now.

39
Arctic sea ice / Re: The 2015/2016 freezing season
« on: February 29, 2016, 01:41:36 AM »
Thanks so much, Jim, but it tells me "Access Forbidden" -- is there a solution?  I have this durned Win 10 laptop now.

If anyone could post the link to the latest manati satellite image of the Arctic, I would be eternally grateful -- I've lost mine.

ASCAT you mean? If so:

http://manati.star.nesdis.noaa.gov/ascat_images/ice_image/msfa-NHe-a-2016055.sir.gif



40
Arctic sea ice / Re: The 2015/2016 freezing season
« on: February 25, 2016, 08:14:56 PM »
If anyone could post the link to the latest manati satellite image of the Arctic, I would be eternally grateful -- I've lost mine.

41
Does anyone think it possible that sea water may have begun to infiltrate the ice in the below-sea-level areas that are in the general area to the east of what used to be the "fork" between the north and south branches? I believe someone posted a map of the topography, and it shows deeper areas in that region.

42
Arctic sea ice / Re: The 2015/2016 freezing season
« on: February 08, 2016, 04:59:04 AM »
Hey Frivolous -- I am originally from Du Quoin!  Nice to see you here!

43
Arctic sea ice / Re: Latest PIOMAS update (February)
« on: February 07, 2016, 07:51:07 PM »
Wouldn't the graph assume certain conditions as, for example, the air temperature above the ice and the water temperature below it?  Possibly it assumes that the temperature of the water is at the freezing point.  What if the water's temperature is actually one or two degrees higher?

The breakup pattern of leads is continuing:

44
Arctic sea ice / Re: Latest PIOMAS update (February)
« on: February 06, 2016, 11:15:12 PM »
Very sorry I don't have images from earlier years -- the qualitative difference is quite stark. 

Wipneus's second graph at Reply 823 is very telling.  PIOMAS would have you believe the ice volume in Nov 2014 was as high as in 2008.  This defies credulity.  We know the ice has changed fundamentally since 2008.

I have been downloading these satellite photos since early 2007... <snippage>

All in all, not qualitatively that much different than what we are seeing now, from what I can tell.

Best guess is, 2016 is acting in accordance with what has been typical since 2010.

45
Nice chunk fell of the northeast, too.

46
Arctic sea ice / Re: Latest PIOMAS update (February)
« on: February 05, 2016, 05:29:07 AM »
I have been downloading these satellite photos since early 2007 (unfortunately, I did not backup the old laptop most of them were on -- now I keep them on a USB drive).  That's 9 years of peering at these images.   In 2007, the ice only barely began to break up at the end of May, and by breakup, I mean that a crack appeared along the edge of the entire Canadian archipelago.  The ice was incredibly thick compared to what we have now.  Recall that land-fast ice shelves existed, some 120-feet thick.  Those all broke away and disappeared in the years after 2007.  Some of these ice shelves covered areas that had not seen open water in 14,000 years.  Those ice shelves had acted as a sort of break on the movement of the sea ice.  Further, although an increasing number of storms were entering the Arctic, during the winter months, this was still a rare occurrence.  Not anymore.

And you have only to look at the speed of the sea ice.  By about 2009, the speed had doubled over the long-term average.  Lord only knows how fast it is moving these days compared to the 1980s, for example. 

Further, the entire character of the sea ice is radically different -- you might as well be discussing the difference between cucumbers and artichokes.  In the past, the ice was very dense and strong, now it is like Swiss cheese made of spongy slush.

Here are some satellite photos from other years (2012 and 2013) at this time:











47
Arctic sea ice / Re: Latest PIOMAS update (February)
« on: February 04, 2016, 05:37:22 PM »
PIOMAS is hopelessly wrong.

The sea ice is right now undergoing its breakup pattern, normally seen in late March ("normal" in the last few years; pre-2007 it was in May-June).

The ice is so thin that the normal currents are breaking it up.  (Not to mention that the ice has been beaten to death by storms entering the Arctic all winter long.)

You can watch it here:  https://weather.gc.ca/data/satellite/hrpt_dfo_ir_100.jpg

48
Nope. I'm gonna go out on a limb and speculate that the northeastern edge of the south branch has collapsed even more.  The southern edge is bound by solid rock, looks like.

Hasn't the eastern side of the south branch sort of "crept up the hill" and now the south branch is much wider?

Isn't Espen's animation (post 1223) clear enough for you on this? Seems to me there is a big step back after the island, widening the South branch as you suggest. I assume bright swathes of white indicate where the ice starts gaining height and it is just floating melee in that stepped back area. Let me know if you think I am wrong which is entirely plausible.

There seems little difference between
http://ocean.dmi.dk/arctic/images/MODIS/Disko/20160104s01a.ASAR.jpg
and
http://ocean.dmi.dk/arctic/images/MODIS/Disko/20160128s01a.ASAR.jpg
at the calving areas. 10 Jan event brightened channel and it has largely remained that way - not sure if that means anything. I am unable to see any effect at calving area and behind that.

Any guesses for how big the island is or how far back the calving front will move by Oct/Nov this year, or any other date for which you would want to hazzard a guess?

49
Would love to see what you guys think of the changes to the eastern sides of the north and south branches.  Hasn't the eastern side of the south branch sort of "crept up the hill" and now the south branch is much wider?

http://ocean.dmi.dk/arctic/images/MODIS/Disko/20160202TERR.jpg

which is also interesting in light of this:

http://ocean.dmi.dk/arctic/images/MODIS/Disko/20160201rs02.ASAR.jpg

50
You know, there is still some serious mass balance loss going on today in almost the same locations.  This can't be normal in January.  Or rather, this can't have been normal in January.  We are in the no-analogue world.

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