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Messages - Tor Bejnar

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1
Arctic sea ice / Re: The 2019 melting season
« on: June 13, 2019, 07:33:03 PM »
The attached piece of a graph posted by Gerontocrat in the 2019 sea ice area and extent data thread makes me think Poseidon intends to thread this needle for a while longer.  But what will happen July 5 (or then-abouts) when the 'needle' closes up?  Not worth a poll, but fun to watch.  (I know Oren commented on this possibility maybe weeks ago.)

2
Arctic background / Re: Arctic Maps
« on: June 11, 2019, 01:21:05 AM »
I usually do know the difference between "Arctic" and "Antarctic", but cross-posts are [something]. :)

And for those who like to see where things are, here is a nice map of the various seas in Antarctica as used in these graphs.

3
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: June 10, 2019, 07:15:45 PM »
Hans Island is mostly steep-sided limestone or dolomite, so it likely erodes mostly from the sides.  Ice floes will basically cause below water line erosion, while freeze-thaw action, chemical weathering and surface runoff will affect the subaerial surface.  Per the internet chemical weathering of maybe "one-twentieth of a centimeter every 100 years" could be expected, but this would be in a more temperate climate, so I'll guess a 0.25 to 0.5 cm of loss this past 2,000 years from chemical weathering.

I'm really just guessing, but 500 good bumps or scrapes per year, so in 2,000 years, what, on the order of a centimeter or two? 




4
Antarctica / Re: Antarctic Icebergs
« on: June 10, 2019, 05:55:58 PM »
A68-A is rotating around a different center now.  I thought it would be closer to the island/peninsula, but it is also 'moving out'.  New PolarView image ('added' to the previous GIF) is from June 8.

5
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: June 10, 2019, 04:07:30 PM »
Quote
… Hans can crack 1 million floes without taking a scratch.
Tor, help me here!
Sorry, B_, but have you heard of glaciers (made of ice) turning "V" shaped valleys into "U" shaped valleys?  It's because the ice, with entrained bits of rock, gouges out the rock.  So the million or so hits taken by Hans Island has eroded Hans Island, sand grain by sand grain - a little faster, probably, than if it was only water flowing past its shores.  (Freeze-thaw processes will be significant in loosening the surface for further erosion.)  I'm sure some of the 'thumps' can be felt by those who visit the island, and those mini- and micro-earthquakes will very slowly take their toll as well (but tiny compared with freeze-thaw).  I don't, however, expect to see any changes to Hans Island except on the hand-specimen level.

6
I'm quite willing to believe you, Hap.  Pity it wasn't a sailboat.   ;D

7
Expect a very heavy calving next!!!!!
As promissed:
Just don't promise us an ice-free Arctic Ocean! :o

8
Arctic sea ice / Re: Sea Ice Melting Affected by Microplastics?
« on: June 09, 2019, 05:20:12 AM »
The Arctic Ocean as a dead end for floating plastics in the North Atlantic branch of the Thermohaline Circulation
Andrés Cózar, et al. - Science Advances  19 Apr 2017
Quote
Abstract
The subtropical ocean gyres are recognized as great marine accummulation zones of floating plastic debris; however, the possibility of plastic accumulation at polar latitudes has been overlooked because of the lack of nearby pollution sources. In the present study, the Arctic Ocean was extensively sampled for floating plastic debris from the Tara Oceans circumpolar expedition. Although plastic debris was scarce or absent in most of the Arctic waters, it reached high concentrations (hundreds of thousands of pieces per square kilometer) in the northernmost and easternmost areas of the Greenland and Barents seas. The fragmentation and typology of the plastic suggested an abundant presence of aged debris that originated from distant sources. This hypothesis was corroborated by the relatively high ratios of marine surface plastic to local pollution sources. Surface circulation models and field data showed that the poleward branch of the Thermohaline Circulation transfers floating debris from the North Atlantic to the Greenland and Barents seas, which would be a dead end for this plastic conveyor belt. Given the limited surface transport of the plastic that accumulated here and the mechanisms acting for the downward transport, the seafloor beneath this Arctic sector is hypothesized as an important sink of plastic debris.
Images (below) from the on-line PDF of Supplementary Materials

9
Consequences / Re: Sea Level Rise Projections and Maps
« on: June 09, 2019, 03:37:35 AM »
I could only see a sliver of the top of the sketch, so I went to the site, pretended to be able to agree to something in Dutch, and found the sketch, mostly reproduced below (I hope). Interesting article (in English).  Edit:  Now I can see the sketch above, so I'm deleting my version...

10
Arctic sea ice / Re: The 2019 melting season
« on: June 08, 2019, 06:03:05 AM »
There was a comment in the Nares thread about how much snow appears to top the floes moving through the strait.  I wonder if one component of "less apparent melt ponding" is thicker snow cover.

11
Quote
Good morning America, how are you?
Still dwelling in yesterday.

The train used to go through Tallahassee on its way to New Orleans, but a hurricane years ago put an end to that.  :'( (But they say it's coming back!  :))

12
Arctic sea ice / Re: The 2019 melting season
« on: June 02, 2019, 03:30:29 PM »
Ice in the Barents marching to it's demise.  I'm guessing this is still being counted as extent?
...
Looks like mass desertion to me.  :'(

13
Arctic sea ice / Re: The 2019 melting season
« on: June 02, 2019, 06:58:28 AM »
Quote
the area above Ellesmere and Greenland (is that what gets called the CAB)?
yes.  In the upper right corner of this page is a link to the ASI Graphs.  Click it, then click the "Regional graphs" tab.  There you'll see the Cryosphere Today based map of the Arctic showing the several (main) areas in the Arctic.  (They ignore the Baltic Sea, for example.)  Click on the map for an enlargement.  Once on the ASIG, you can spend hours (months, years even) studying the maps and graphs and links.

14
Science / Re: 2019 Mauna Loa CO2 levels
« on: June 01, 2019, 06:46:59 PM »
Wolfpack's graph suggests the CO2 rate of change changes sinuously (albeit with much noise) on a ~3-4 year cycle since 2008, at least.  I didn't find anything with a quick internet search.  Am I missing something?

15
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: May 31, 2019, 04:40:55 PM »
Here, for history's sake (B_ is faster than a speeding bullet), is an animated enlargement of First being stuck on Hans Island, 'enlarged' to 61% of full resolution.

16
This part of Petermann Glacier has earlier melt ponds in 2019 than in 2016, '17 or '18.  GIF made from images "dated" May 30 from these four years.  (Date of actual Sentinel-hub Playground image may be earlier, as the 2019 image is actually May 29.  I note the 2016 image has a 'different' shadow.)  You certainly can see the glacier tongue moving year by year!

17
Arctic sea ice / Re: Basic questions about melting physics
« on: May 29, 2019, 06:39:39 PM »
Sorry for the aside, but there can be a problem with
Quote
you would not consider a human inside of a building to be part of the building
   When calculating the energy needs of a building (e.g., heating and A/C), the humans can be a significant component.  (Years ago I did public building energy audits.)

I have no clue, however, about salt water freezing and 'fresh' ice thawing issues.

18
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: May 28, 2019, 05:06:21 PM »
This GIF uses DMI Sentinel images from May 24, 26 and 27 (no 25th image available) and shows the "First" floe (crudely outlined) getting stuck on fast ice above Hans Island.  It doesn't block the channel, however.  As it is 'surely' made of MYI, I expect it to just sit there awhile.  For me the question is what happens with regard the "Second" floe.  When it hits First, will either shatter?  Will First get nudged along?  Will they block the Kennedy Channel?  If so, for how long?  (It could be until July.)

So much for my "they always shatter" experience (maybe).  :o ::) :P

19
Arctic sea ice / Re: Northwest Passage thread
« on: May 24, 2019, 05:23:27 PM »
I'm reminded of Matt Rutherford's record-setting circum-Americas voyage. (See August 9, 2011 comment on ASIB)  I followed Matt's voyage from then, but hadn't visited the http://solotheamericas.org/ website since about 2014, so I didn't know about the movie “Red Dot on the Ocean". 

20
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: May 22, 2019, 05:04:54 PM »
DMI Sentinel images from Kane, Kennedy and Lincoln folders for May 17, May 19 and May 21 are stitched together and into a GIF.  3 floes 'marked' to aid viewing, and dates are in the Lincoln Sea. 

Flow is straight forward in Lincoln Sea and Hall Basin (by Petermann Fjord), but in Kane Basin, there is an eddy.  I suspect the yellow-outlined floe was fast ice that grew within Kane Basin.  There are a couple of floes 'following' the marked one while on the Ellesmere (Canadian) side of the basin the ice bits zoom southward. [I'm sure it will need a click.]

Note that just off of NNW Greenland the ice moved a little between May 17 and 19, but not at all between May 19 and 21.

21
Arctic sea ice / Re: The 2019 melting season
« on: May 22, 2019, 02:53:10 PM »
Worth looking at this to compare
My IE shows this as a little box with an X.  The link is
https://www7320.nrlssc.navy.mil/GLBhycomcice1-12/navo/beaufortictn_nowcast_anim30d.gif
"Security" is bad, but I go to this Navy site with peace of mind.

22
Rich,
Go to the upper right corner of this web page and type "ozone" in the search field. Several postings that mention the word will be listed, and some of them may answer your question.  (Hope this is helpful.)

23
You need to zoom in on this gif from hycom to see the impressive outburst of freshwater from Jakobshavn around the 11th
For the casual viewer who is not certain where Jakobshavn Glacier is located (thanks to Wikipedia):

24
Greenland and Arctic Circle / Re: The 'Very Big Chunk' poll
« on: May 15, 2019, 09:42:28 PM »
Without moving a muscle! :o ;D :P

25
Antarctica / Re: Antarctic Icebergs
« on: May 14, 2019, 09:39:50 PM »
A68A is mostly rotating between April 15 and May 14: today's PolarView compared with last month's composite.

26
Arctic sea ice / Re: Arctic Image of the Day
« on: May 14, 2019, 08:14:06 PM »
Hey, the perennially open door is closed!

27
Greenland and Arctic Circle / Re: The 'Very Big Chunk' poll
« on: May 14, 2019, 06:28:23 PM »
Surprise, surprise: it shattered. (Today's DMI Sentinel image)

28
The rest / Re: Is Man the "Unnatural Animal?"
« on: May 14, 2019, 05:16:04 PM »
It is natural to take care of one’s needs.  (I’m thinking Maslow’s hierarchy of needs).  At an evolutionary level, it made sense to live longer, the ‘grandmother hypothesis', where we became better at transferring knowledge from generation to generation.  Once we learned how to write and read, this ‘ability to take care of our needs’ was extended.  All quite natural.

What we got with the ‘good stuff’ were the questions: “Who are we?”, How’d we get here? “Why did we survive?”  And Bingo:  religion.

Even mundane things get immortalized “religiously” [see this Snopes article].  On some concepts, we get truly stuck, such as with “Be fruitful, and multiply, and … subdue [the Earth]: and have dominion over …every living [thing] …” (Genesis 1:28).  I intentionally left out (where the first ellipsis is) “and replenish the Earth”, because it is ignored while the rest is held as “God’s Truth” (by ‘western civilization’ for about 4 thousand years, and who knows for how long by other ‘civilizations’).
 
So I suggest “unnatural” is when we don’t get the message straight [edit: accurately] from our ancestors – where we go by ‘belief’ and not ‘understanding’.

I am religions, but my faith is based on experience (mine and my forebears) and upholds understanding and questioning (and minimally on ‘rites’), as does the scientific method.  [Included ‘rites’ include style of worship service, tools for engagement and a shared vocabulary.]

29
Different from the post above, these two SentinelHub Playground images are 28 days apart showing Petermann Glacier is moving about 3 meters per day (at this location).  The orange lines are in the dip of the mid-glacier stream valley on the April 14 and May 12 images.

30
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: May 14, 2019, 01:28:35 AM »
Welcome, Maven, to the ASIF!
I hope you are as likeable as you are liking.  :)

31
This is in line with publications that show that global temperatures are over 100% caused by humans:
Quote

the IPCC’s implied best guess was that humans were responsible for around 110% of observed warming (ranging from 72% to 146%), with natural factors in isolation leading to a slight cooling over the past 50 years.

Similarly, the recent US fourth national climate assessment found that between 93% to 123% of observed 1951-2010 warming was due to human activities.

These conclusions have led to some confusion as to how more than 100% of observed warming could be attributable to human activity. A human contribution of greater than 100% is possible because natural climate change associated with volcanoes and solar activity would most likely have resulted in a slight cooling over the past 50 years, offsetting some of the warming associated with human activities.

32
Antarctic Tectonics post #104
Quote
Scientists discover 91 volcanoes below Antarctic ice sheet
This is in addition to 47 already known about and eruption would melt more ice in region affected by climate change

33
Antarctica / Re: PIG has calved
« on: May 11, 2019, 05:22:21 PM »
Someone with the know-how could update the Wikipedia page with a link to an image and "Credit: Arctic Sea Ice Forum"    :)

34
Arctic sea ice / Re: Arctic Image of the Day
« on: May 10, 2019, 07:43:20 PM »
Says the floe:  I liked being called an iceberg: made me feel big and strong!  And what are those 'see-thingies' that are used to look where one is going?  I thought life was like a waterpark at night.

Says Tor: wonderful image, B_!

35
Quote
a recent resumption of global warming after a hiatus in the 2000s
from a few posts up
Tamino says there was no global warming pause in the first decade of this century (for example, here) and regularly shows the math (or 'maths' if you're not American) to prove the statistical insignificance of what is called a pause.  Anybody who says there was was pause should pass their proof on to Tamino, I think.

36
I searched the ASIF Glossary for most of the acronyms AbruptSLR used in his recent posts, and if not found, gathered them (with definitions I knew or slewthed) into a single post.  If you are looking for a (scientific-related) acronym's meaning, first look in the first post of the Glossary (Neven adds Arctic-related terms regularly), then use the Search feature on that thread (upper right corner of webpage).  If not found, figure out what the acronym means (Abrupt's context may help, or search this thread for previous use) and post it into the Glossary. Obviously, if I got a definition wrong, please let me know so I can correct my post.

Edit:  if definitions are included within the post, I don't look further.  (For example, Abrupt's next post - an abstract - uses lots of acronyms, but all are defined.)

37
Arctic sea ice / Re: Glossary ... for newbies and others
« on: May 07, 2019, 06:59:39 PM »
Terms frequently used by AbruptSLR in discussions about Antarctica ice shelf melt (and not explained elsewhere in the Glossary).

AABW - Antarctic bottom water
ABW - Arctic bottom water
ASE - Amundsen Sea Embayment - is roughly the size of the state of Texas and the area is known as the Amundsen Sea Embayment (ASE); it forms one of the three major ice drainage basins of the West Antarctic Ice Sheet, the others being the Ross Sea Embayment and the Weddell Sea Embayment (from Wikipedia)  - the ASE includes Pine Island Glacier (PIG) and Thwaites Glacier (at the base and to the west of the Antarctic Peninsula)
CDW - Circumpolar Deep Water
GIS - Greenland Ice Sheet [or course, this is in the Arctic!]
MICI - marine ice cliff instability
MISI - marine ice-sheet instability
PIIS - Pine Island Ice Shelf
SAM - Southern Hemisphere Annular Mode (Wikipedia)

38
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: May 07, 2019, 05:43:19 PM »
In the Kane Basin these days, a floe has moved 40 km in 3 days.  (Floe outline is approximate.)  (annotated DMI Sentinel images)

39
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: May 07, 2019, 02:47:00 PM »
I'm grateful to those who have introduced us to the effects of tides in the Nares Strait/Lincoln Sea region.  I had previously presumed it was all wind.  (I learn something new every other day.)

40
Greenland and Arctic Circle / Re: The 'Very Big Chunk' poll
« on: May 04, 2019, 08:05:14 PM »
DMI Sentinel image from today:  VBC, apparently, is an amoeba, and has split in two!  Plenty of size for either to get stuck, but do they have the will?  [Sorry to those who are bothered by the anthropomorhizing of unsuspecting bits of inorganic ice.]

41
Policy and solutions / Re: Carbon Capture and Storage (CCS)
« on: May 03, 2019, 04:42:19 PM »
Renewables ‘Have Won the Race’ against Coal and Are Starting to Beat Natural Gas

By Joe Romm, originally published by Climate Progress (April 4, 2019)
Quote
… according to a report released this week by Bloomberg New Energy Finance (BNEF).

42
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: May 02, 2019, 08:18:19 PM »
Not only is there the crack B_ identifies, there is about 9 km (at least in one place) of movement in the once stable 'triangle' on the NNW coast of Greenland.  Yellow "x"es approximately mark several identifiable locations.  A couple of ovals show pieces associated with the "Very Big Chunk" (VBC) spreading apart (whether part of the original VBC, I have no opinion) even as most of this Lincoln Sea ice moves toward Ellesmere Island (left edge).  [Images from DMI - May 1 and May 2]

Edit:  Yes, some of the 'triangle' (not viewed here) remains. not hardly any!

43
Greenland and Arctic Circle / Re: The 'Very Big Chunk' poll
« on: May 02, 2019, 03:33:19 PM »
I also 'love' polls like this that get us to look closely (as a community) at floe behavior.  I imagine 30 or 50 posts about a single floe in the Nares Strait thread would be tedious to someone not interested in this minutia.  Besides, there are links in each thread pointing to the other, so the 'interested person' won't miss what they don't want to miss.

And besides, watching a horse race can be plain fun if you are not overly invested in a particular outcome.  A 'floe' horse race (usually) has no particular consequences for The Big Picture, and so lets us laugh a little - something that is surely needed, given the grave Big Picture.

44
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: April 30, 2019, 05:05:23 PM »
JAXA ARCTIC EXTENT :- 12,359,667 km2(April 29, 2019)
...
Including 2016 [2015-16] in the "JAXA ARCTIC Extent Gain (+) Loss (-) in Km2" chart would give a feel for the horse race these next two months.  [2018 is so 'last year'  :P ::) 8) :o ;D]

45
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: April 30, 2019, 04:42:15 PM »
The (relatively) warm weather in Greenland is reflected in a further spike in the melt extent:
...
I was curious to compare Ben's chart with 2012 - the year of the big melt.  NSIDC gives the comparison with their interactive map (with 2012 and 2019 pre-selected!)  I selected the years with notable early melt to put 2019 into perspective (below).  Note that the 'grey zones' hardly register until May.

46
Further to what Thomas posted above concerning a crevasse on the NW side of the glacier, the mid-glacier crevasse has also widened over the course of a year.  Images are from Sentinel-hub Playground (April 2018 and April 2019).  The date bars are 150 meters wide and about 38 meters tall.  The location of the crevasse is near the bottom of the image in this post.

47
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: April 29, 2019, 07:11:07 PM »
Another view of the very temporary blockage by Petermann Fjord shows the large floe started breaking up 'right away'.  DMI-Sentinel images dated April 26, 27, 28 and 29. (Slight pause on first and last images).

I find it interesting that the floe appears to have not affected the fast ice opposite Petermann Fjord.

48
an Unidentified Identified Object?
:)

50
Arctic sea ice / Re: The 2019 melting season
« on: April 27, 2019, 03:42:23 PM »
According to the NSIDC chart, sea ice extent has been recovering, albeit minutely, in the past couple of days. How does this gel with the weather discussion here? Does it mean anything? Should we expect to see a rapid drop in the next few days?
...
Welcome Maplike to the ASIF (Arctic Sea Ice Forum)!
When the Arctic weather appears to be 'bad' and extent doesn't drop, some interpret this to mean the ice is breaking up and spreading, allowing SIA (sea ice area) to decline while maintaining SIE (sea ice extent).  [For frequently used abbreviations, see Glossary.]

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