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Messages - Thomas Barlow

Pages: [1] 2 3 4
1
Arctic sea ice / Re: The 2017 melting season
« on: July 27, 2017, 05:23:10 PM »
Let's face it, even a minimum anywhere even close to 2012 or 2016 is still bad news, since we know the oceans are warming and Atlantic surface water is infiltrating, CO2 is still rising.

However, with regard to this season, with the Arctic Ocean at the lowest volume, possibly on record, as far as we can tell (Oren's Inner Basin graphs), I don't see how anyone can think this is a humdrum year. Isn't most peripheral ice irrelevant to what happens in the Arctic Ocean? There are still icebergs in Hudson Bay right now for example.
We'll see, the volume of the Arctic Ocean (AO) could recover to be in the 'near-disasterous' range of 2nd or 3rd lowest for the Arctic Ocean, as Oren predicts.
I personally have no real idea if it will be the lowest volume for AO, but that large area of pretty integrated ice from just NE of Greenland out towards Beaufort and up towards Chucki Sea could save the day (for extent at least).

Our arena has changed and I think people look at the graphs so much they forget. Pretty hard for any post to be conservative here. I'm just glad a few people on the planet are at least paying attention, and talking about it here, wether conservative or slightly alarmist.

It's all in the depth of the dip.
Compare to 1980 (yellow at top), pretty nice reasonable inverted parabola.
(1980 - the year I quit the corporate world and the mainstream world, and went looking for answers, since it was clear governments and industry were incapable of meaningful action or insightful comprehension. Hopefully it's not too late, 35+ years later)

2
Arctic sea ice / Re: The 2017 melting season
« on: July 26, 2017, 04:43:09 AM »
This animation shows only peripheral ice (in black), comparing 2012 and 2017, which, apart from some left over in the CAA, will likely disappear in the next few weeks, affecting volume and extent graphs more than may be being predicted. In other words, the stuff that is most likely to disappear, is the most important part right now as to how it affects extent and volume in the coming weeks. The Pacific side, with extra ice from 2012, may not make up the difference enough.

3
Arctic sea ice / Re: The 2017 melting season
« on: July 26, 2017, 12:28:01 AM »
August 1 2016 on top.
Today, July 25, 2017 on the bottom.
(north of Greenland)
Of particular note is the fjord.  Ice free in 2016 yet still frozen in 2017.
Perhaps the difference in dates creates that artifact. Wait a week until Aug. 1, the date of the 2016 image.

4
Arctic sea ice / Re: The 2017 melting season
« on: July 25, 2017, 07:15:01 PM »
August 1 2016 on top.
Today, July 25, 2017 on the bottom.
(north of Greenland)

5
Arctic sea ice / Re: The 2017 melting season
« on: July 25, 2017, 03:30:52 PM »
A river of mush in the Lincoln Sea yesterday.

6
Arctic sea ice / Re: The 2017 melting season
« on: July 24, 2017, 09:56:10 PM »
Ok, I gave it a go. Didn't seem worth it in the end.
You live and learn.
I could have used their higher quality images, but would have taken too long.
Fram and north.
(Right-click - open image in new window, zoom-in for closer view)

7
Arctic sea ice / Re: The 2017 melting season
« on: July 24, 2017, 07:15:04 PM »
Sentinel 2 images the Beaufort Sea much more frequently than Sentinel 1. The reverse is true for (most of) the CAB however!
Thanks., I always wondered why people don't use Polar View more often.
Is there a magic 'composite view' on Polar View', or do I have to composite several images myself? (sorry, not sure the proper place for this question0

8
Arctic sea ice / Re: The 2017 melting season
« on: July 24, 2017, 04:50:35 PM »

Personally I reckon the risk is still very real on Pen Hadow's planned route!
Yes, going from Alaska seems ambitious. Wouldn't Iceland be a better point, and then past Svalbard somewhere. Maybe too stormy?

9
Arctic sea ice / Re: The 2017 melting season
« on: July 24, 2017, 04:25:19 PM »
You appear to be thinking of Sentinel 2? Sentinel 1 covers most of the Arctic apart from a modest "Pole Hole".
See below for an example. Much higher resolution available via: http://www.polarview.aq/arctic
Guys, please try to keep this forum free of comments that belong elsewhere.

Is this sufficiently on topic? What should one do if folks keep on making misleading remarks in here?
Yes, I meant Sentinel Playground. Is Sentinel 1 updated almost daily? Seems only updated for a certain area once in a while? Sentinel 2 seems more frequent?
For example, on topic, here's part of the Beaufort near Banks island, in Sentinel Playground a couple of days ago. I don't know how to do that with Polar View?
Click for best resolution:

10
Arctic sea ice / Re: The 2017 melting season
« on: July 24, 2017, 02:32:17 PM »
Hi,

Just curious, I've been lurking for a while,  and while I see a lot of pics posted, I don't see a lot posted pulling from the sentinel satilte missions, is there a reason why? ( Or is it and I'm just not realizing it)

In the same vein the sentinel 3 sat data is available now, and when I played around with it in the sentinel toolbox it looks like you could use it to really clean up the swaths and get some very clear images of the ice. I was.mostly just fooling around, but it looked like you could run algorithms against pixels based on the cloud masks. You can also use it to process the sentinel 1 and 2 data the same way. Might be easier than Photoshop. Apologies if this belongs in stupid questions  :)
Liam
I've tried most of these, and I haven't seen a good method that works very well. Although the Sentinel cloud opacity slider seems ok, but I'm not sure it is using the most recent image to do that. It seems to be using a previous (older) image to fill in.
Layering in Photoshop, and very laboriously erasing clouds layer to layer, is the only other way, and often not that satisfactory, except if you are just trying to remove cloud from a couple of days images.

Regarding using Sentinel for Arctic, I'm not sure, but does it really go into the Arctic? Seems to cut off at the top of Greenland and all around that latitude, not really imaging the Arctic Ocean, only the peripheral of it?

11
Arctic sea ice / Re: The 2017 melting season
« on: July 23, 2017, 08:37:18 PM »
So, on balance, I could see the case for a slowdown in extent losses...

Thanks, Cesium. Yet to tie with 2013 and 2014 we would need to see sustained reduction in SIE losses from now till the end of September. The CAB would need to 'hold' its integrity for one.
I think there is more peripheral ice (eg. Baffin Bay, Greenland Sea, Novaya Zemlya) than many previous years, and that will disappear, causing a larger than usual drop in extent, since it is all adding to an illusory extent right now. The CAA may hold out better than usual, as it seem thicker than usual, but if the CAA does get a decent loss, then the overall extent could drop, even if the CAB losses are at a relatively normal rate.

12
Arctic sea ice / Re: The 2017 melting season
« on: July 23, 2017, 08:14:31 PM »
Explorer expects NP to be open water this summer. Plans to sail to the pole in a yacht.

http://www.pressreader.com/new-zealand/the-dominion-post/20170724/282089161833092

13
Arctic sea ice / Re: The 2017 melting season
« on: July 23, 2017, 12:34:08 AM »
What good is extent if thickness is incomparable to 2012?
http://sites.uci.edu/zlabe/files/2017/07/sit_PIOMAS_mask_June17.gif
What's left over is very thin. 95% of 2 meter ice is gone now, 99% of the 3, 4 and 5 meter thick ice too.

This takes that graphic and removes ice below 2 metres, and shows only (June) 2012 and 2017.
What do you guys think?
How much overall thickness loss is possible in 6-8 weeks left? Not 2 metres I wouldn't think.
Maybe 1 metre?

14
Arctic sea ice / Re: The 2017 melting season
« on: July 21, 2017, 05:42:31 PM »
I have marked the region (red oval) which roughly defines the area that is more integrated (unbroken) than some previous years, from looking at Worldview occasional gaps in the clouds in recent weeks. The area is more robust than several previous years (apart from maybe some sticky land-fast ice stuck to coasts this year).
However, the thickness may be low in the region marked.

Conclusion: Mush most places in the Arctic Ocean, with a nice, very large region of robust ice, could almost walk across for 100s of miles, but which is vulnerable due to thin ice status.

(PS. I know DMI changed their methods over the years, but it is not that big a difference, and I do think they are more accurate than the US navy for example. :)  )

15
Arctic sea ice / Re: The 2017 melting season
« on: July 19, 2017, 08:51:10 PM »
Sea ice compactness at this moment seems to be substantially higher than in 2012, 2015 and 2016.
Thomas Barlow
That is some good news at least. Thanks.
Could slow down the rest of the melt-season. A huge area of icepack towards 'west' side of the NP looks somewhat integrated from looking at Worldview.

magnamentis
would be good news if it were true while the exact opposite is the case IMO.
Tigertown
I would have to trust my own eyes on that(compactness of any measure), among other sources.

Here you go.
Shows nearest least-cloudy day in 2016 ( bottom), compare to July 17 2017 (on top),

16
Arctic sea ice / Re: The 2017 melting season
« on: July 19, 2017, 05:23:11 PM »
Sea ice compactness at this moment seems to be substantially higher than in 2012, 2015 and 2016.
That is some good news at least. Thanks.
Could slow down the rest of the melt-season. A huge area of icepack towards 'west' side of the NP looks somewhat integrated from looking at Worldview.

17
Arctic sea ice / Re: Latest PIOMAS update (mid July update)
« on: July 18, 2017, 05:54:51 PM »
Thanks again to Oren for the Inner Basin Graph.
I think this is the most interesting information going on right now.

Just for fun, I did try to make an adjustment (in red) for the CAA, by adding about 100+ km3 more loss, to indicate Arctic Ocean only as of now, and even though it does not make much difference right now, I intuit it does change the potential trajectory a little, which over time, could be a lot.
A lot of the Arctic Ocean is clearly vulnerable, especially if the next 2 months are warmer than usual. ( I consider the Arctic Ocean separate from everything else, since I think that at some point, a phase transition (tipping point - ie. collapse) is reached, because it is an ocean - not a fjord.)

18
Arctic sea ice / Re: Latest PIOMAS update (mid July update)
« on: July 18, 2017, 05:35:59 PM »
An update to the Inner Basin volume chart. The gap to 2012/2011 closed by ~300km3

In any case, my table shows 2017 having some more volume in the CAA. In absolute figures it's 579 km3 vs. 462 in 2012. It's not a huge difference though.
Right, so for the Arctic Ocean, the gap closed in on 2012 by <200km3, not ~300km3 ? :-)
Thanks again !  Great work!

19
Arctic sea ice / Re: Latest PIOMAS update (mid July update)
« on: July 18, 2017, 04:42:44 PM »
Just for comparison here is the CAA at in Sept. 2016

20
Arctic sea ice / Re: Latest PIOMAS update (mid July update)
« on: July 18, 2017, 04:23:26 PM »
An update to the Inner Basin volume chart. The gap to 2012/2011 closed by ~300km3, which is ~200km3 more than expected by my "method" and a sign of lowering probabilities for records. My next extrapolations were shifted upwards accordingly. In my next post I will attempt to find out which region contributed the most to this.
Thanks for the graph! Great to see !
It would be interesting to see if the CAA is making a difference to the overall here ( I think you include CAA?).
On its own the Inner Basin graph may look different without all that thick ice stuck in the CAA this year (compared to 2016 and 2012).
You don't have Baffin Bay in there right?

In other words, there appears to be more volume in the CAA this year than in these other years shown below. So that could skew the main Arctic Ocean volume figure.

DMI - I took out Arctic basin just to focus on looking at CAA
(I know they changed their method over the years, but this is close enough visually.)

21
Arctic sea ice / Re: The 2017 melting season
« on: July 18, 2017, 04:10:52 AM »
I think mentioned already, but Kara mush won't last long.
One of the many peripheral areas that are bolstering the extent a little. I think a lot of the peripheral will be gone real soon.
If the Pacific side does not hold up, things could get close.
Actually think some survival is possible in the Baffin bay. There were still icebergs in the Baffin in Late September last year, and the ice looks to be in better shape there this year and the weather has been quite cold recently. Baffin survival is not unprecedented either, used to happen semi regularly in the 80s and before the satellite record.
Yes, I could see that. The ice is thicker there this year. Although the cold SSTs and air temps appear to be due to ice presence and ice melting more than anything else.
The extra thickness right now, could make a difference, although there really was nothing left to speak of there last year by mid Sept. Judging by clicking through Worldview, August-Sept. last year, I'd be surprised if there would be anything much there by mid-Sept. 2017, but maybe that extra thickness now could make a difference.

22
Arctic sea ice / Re: The 2017 melting season
« on: July 17, 2017, 11:07:00 PM »
I think mentioned already, but Kara mush won't last long.
One of the many peripheral areas that are bolstering the extent a little. I think a lot of the peripheral will be gone real soon.
If the Pacific side does not hold up, things could get close.

23
Arctic sea ice / Re: The 2017 melting season
« on: July 16, 2017, 10:29:09 PM »
For what it's worth, this animation more or less shows the difference in extent for 2016 and 17 for this day (from Polar Portal) A bit rough, but, ie. 2016 extent that 2017 does not have, and 2017 extent that 2016 did not have.

24
Arctic sea ice / Re: The 2017 melting season
« on: July 16, 2017, 09:43:00 PM »
Here's a comparison of DMI SST anomalies for 2012 (left), 2016 (middle) and 2017 (right) for July 15th. I would say that 2017 is well ahead of 2012 on the Pacific side, slightly behind on the Atlantic, and I'm somewhat surprised that no red still hasn't shown up in the Laptev Sea this year. The story for 2017 vs 2016 is the same, except that 2016's lead on the Atlantic side was much larger. But given the current forecast, with persistent high pressure on the Siberian side of the Arctic, 2017 might still catch up.
Hi Neven, did you have those images saved, or is there a way on the site to get the image for 2016? (high quality)
thanks.
http://ocean.dmi.dk/satellite/index.uk.php

25
Arctic sea ice / Re: The 2017 melting season
« on: July 13, 2017, 07:15:48 PM »
If this sliver of green goes in the next week or two, and replaced by blue-purple (basically broken-up 1m ice), the situation becomes dynamic and unpredictable.

Compare the same area in 2016:

26
Antarctica / Re: Rift in Larsen C
« on: July 13, 2017, 02:54:36 PM »
Greetings ASIF, long time lurker here, moved to post by the Larsen C event!

It is fascinating to read the media reaction: many glaciologists seem to be falling over themselves to say there is no reason to think there is any connect to climate change here. I find that weird.

Yes, it would be abnormal if there was no such thing as global warming going on.

27
Greenland and Arctic Circle / Re: Greenland 2017 melt season
« on: July 13, 2017, 02:48:50 PM »
''Low surface ice loss on Greenland this year due to heavy snowfall – consistent with climate warming''
- Jason Box

http://jasonbox.net/low-surface-ice-loss-greenland-year-due-heavy-snowfall-consistent-climate-warming/

28
Antarctica / Re: Rift in Larsen C
« on: July 13, 2017, 02:10:00 AM »

Time to lock this thread....:)?
No. Where will it go? Will it break up? Who owns it?

29
Arctic sea ice / Re: The 2017 melting season
« on: July 13, 2017, 12:22:56 AM »
The Larsen calving is not the defining event of today's state of affairs.
My point exactly. So why did you talk about it here? ... again  :)

30
Does anything think there could be a relationship (conjoining) of these 3 features in the future?
This is from July 8. That seems to be a crack cutting partly across the main central drainage channel, not just another stream flowing into the drain.
(maybe get a better view next time the clouds clear)

31
Arctic sea ice / Re: The 2017 melting season
« on: July 12, 2017, 10:07:12 PM »

32
Antarctica / Re: Rift in Larsen C
« on: July 12, 2017, 02:59:59 PM »
.

33
Antarctica / Re: Rift in Larsen C
« on: July 12, 2017, 02:56:17 PM »

Iceberg twice size of Luxembourg breaks off Antarctic ice shelf

A giant iceberg twice the size of Luxembourg has broken off an ice shelf on the Antarctic peninsula and is now adrift in the Weddell Sea.


Yup. There it goes.
(from my screenshot of NASA Worldview today)

34
Arctic sea ice / Re: The 2017 melting season
« on: July 11, 2017, 05:26:17 PM »
This shows one week of change from DMI.
July 3- 10th

35
Arctic sea ice / Re: The 2017 melting season
« on: July 11, 2017, 04:07:07 PM »
A follow-up to the last post. This is thickness on July 1st, 6th, and 11th. Also, projected thickness for the 16th and 20th. Notice that thickness and volume go down, while extent takes only a minor hit.
CLICK IMAGE


Whoa. That seems very dramatic.

36
Arctic sea ice / Re: The 2017 melting season
« on: July 11, 2017, 04:05:17 PM »
Thomas,
You are right that ACNFS Hycom images are shown often on the forum.
But the year-to-year comparisons are really not that reliable.
For example, I understand that the 2012 image was produced by a different version of the model.
You are comparing apples and oranges with that 2012-2017 comparison.
Yes, I did suspect that. Thanks.
I would go as far as to say 2012 is such an anomaly, all of the research groups were wrong for some reason. They were all still developing (and still are), and I think it was over-blown. Probably still the record, but maybe not as bad as it looked. I think 5 years later, all of the systems will have improved a lot.

37
Arctic sea ice / Re: The 2017 melting season
« on: July 11, 2017, 01:32:50 AM »
One more model from the ESA. For 7-11;2012, 2016, and 2017.
A little different, but still showing the pitifulness of the ice thickness this year.
CLICK IMAGE


Whoa.
Anything can happen.

38
Arctic sea ice / Re: The 2017 melting season
« on: July 10, 2017, 11:27:21 PM »
Is there a peer-reviewed published paper that said that?

39
Arctic sea ice / Re: The 2017 melting season
« on: July 10, 2017, 11:23:20 PM »
Here they are together, to compare side by side.
I feel like the dates must be wrong they are so different. Sorry folks. Double-checked them though.
I guess they're similar if I twist my head around :-)

40
Arctic sea ice / Re: The 2017 melting season
« on: July 10, 2017, 11:17:24 PM »
Here's another one.
Looks completely different, even comparing apples to apples.

41
Arctic sea ice / Re: The 2017 melting season
« on: July 10, 2017, 10:46:04 PM »
Are we sure about ACNFS being such a reliable source to be able to make such comparisons?
I only use it because everyone else here uses it. I think they're pretty rough. But since people seem to like it, there you go.

They are all rough, very inaccurate, and approximations. All of the data sets from every source. Very large margin of error.

42
Arctic sea ice / Re: The 2017 melting season
« on: July 10, 2017, 10:40:59 PM »
Or, put another way...

43
Arctic sea ice / Re: The 2017 melting season
« on: July 10, 2017, 10:37:30 PM »
Are we sure about September?

44
Arctic sea ice / Re: The 2017 melting season
« on: July 06, 2017, 01:43:13 AM »
Yes, the NSIDC chart does a 5 day running average, as has pointed out on occasion.

The Actual daily values for 2017 NSIDC SIE are;                   2012 values.   July 3rd is day 185
x 106 km2

                                                                                   
2017,    07,  01,      9.244                                                   2012,    06,  30,      9.335
2017,    07,  02,      9.154                                                   2012,    07,  01,      9.062
2017,    07,  03,      9.087                                                   2012,    07,  02,      8.971
2017,    07,  04,      8.963                                                   2012,    07,  03,      8.954

Wasn't 2010 was the lowest for this date?
Ah yes, thanks. Forgot to check that. Not for long though maybe?

45
Arctic sea ice / Re: The 2017 melting season
« on: July 05, 2017, 10:12:08 PM »
Should I be worried?
Am I right in saying that for the day, July 4th was within one day's melt (more than 100 thousand  square KMs a day right now) for Day 185, of overtaking 2012 to be the lowest on record for this time of year?

http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/\\ (July

Day 185 - July 3rd and 4th of the respective years

46
Arctic sea ice / Re: The 2017 melting season
« on: July 03, 2017, 05:06:51 PM »
I'm thinking this is going to overtake (or is it 'undercut') 2016 in the the next day or so.
Only 2012 left after that, and real close.

http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/

47
Based on this I have revised upward my guesstimate to 3.0-3.5
---> https://forum.arctic-sea-ice.net/index.php/topic,1834.msg119231.html#msg119231
I still think the icepack is pretty trashy and vulnerable, so still estimating low.

48
Based on this I have revised upward my guesstimate to 3.5-4.0
---> https://forum.arctic-sea-ice.net/index.php/topic,1834.msg119231.html#msg119231
I still think the icepack is pretty trashy and vulnerable, so still estimating low.

49
Arctic sea ice / Re: The 2017 melting season
« on: July 02, 2017, 10:18:49 PM »
just consider that the inner basin currently contains all the remaining thicker ice that was located on the pacific side last year, hence even though the number itself will be interesting, it might as well be a bit misleading when it comes to validation of the thickness. the inner basin and the atlantic side are the only regions that got replenished with slightly thicker ice from the caa and the pacific side

Yes, I think you are right.
Here I deleted all ice about 1m thick. So shows ice over 1m thick.
Just eyeballing 2016 to 2017 at top, to the same day in 2012. Even if this is just very approximate, 2012 looks much worse.
I may have to revise my guestimates for Sept. minimums.
Still looking forward to the next 'Inner Basin' volume chart though.
Looks really bad in the Arctic Ocean 2012.

50
Arctic sea ice / Re: The 2017 melting season
« on: July 02, 2017, 09:01:53 PM »
The main question mark of this stage will be resolved very soon with the end-June PIOMAS data. If the lead is preserved, the race is still on. Should the volume lead crumble to dust in the inner basin, 2017's chances for top finish will crumble as well.
I look forward to the next 'Inner Basin' volume graph !
It's hard to see much here below yet, but considering this shows that the volume for the N. Hemisphere sea-ice is now crowding in on the lowest years for this time of year, and the Arctic Ocean was at lowest volume a couple of weeks back (re. your graph), most of the volume loss being seen for the hemisphere would have to be outside the Arctic Ocean for the 'Inner Basin" graph to slow descent and even out with previous years.
I guess, Hudson Bay, Baffin Bay, Greenland Sea, melting out could cause the hemisphere volume to drop more than previous years, but theoretically the 'Inner Basin' could still not change much.
I think it will still be lowest volume for Inner Basin, and if it is, all bets are off.
I look forward to seeing the results !

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