Support the Arctic Sea Ice Forum and Blog

Show Posts

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


Messages - AmbiValent

Pages: [1] 2 3
1
Arctic sea ice / Re: The 2019 melting season
« on: August 25, 2019, 10:51:07 PM »
For the first time this year, starting to see some ice formation in the ESRL model: yellows and browns in the figure, on the Asian side to the N of where very strong bottom melt continues.
Strong melt right next to strong freeze looks odd - or rather more like ice movement instead of change. I expect a stronger contrast between whole regions in Start-to-Mid-September.

2
Arctic sea ice / Re: The 2019 melting season
« on: August 25, 2019, 07:55:13 AM »
The ice appears to be retreating or getting weaker at Franz Josef and the Laptev bite, but the numbers are barely moving. Is there already strong refreeze balancing the melting, or are both melt and refreeze weak right now?

3
Arctic sea ice / Re: Are you hoping to witness a BOE?
« on: August 23, 2019, 06:25:20 PM »
A BOE is pretty irrelevant. It will be small beer compared to all the other stuff that happens as and when enough CO2 for a BOE to be possible accumulates. A BOE will simply be a symptom that we are living in a 2-3C world, it won't actually cause anything extra to happen in that world.

If we get there under BAU, I hope to live that long, but I also hope BAU dies in the next decade.
I fear that while a single BOE just barely fitting the requirement might not mean much "extra", but the less sea ice there is to melt, the more we will move from an Arctic that spends the summer around 0C to a warmer one - and some regions will make the transition earlier than the rest. Or rather, we have clearly left the start of the transition behind us and are slowly on the way to the other side.

4
Arctic sea ice / Re: Are you hoping to witness a BOE?
« on: August 23, 2019, 09:01:21 AM »
In which interpretation? Essentially no sea ice or just below 1Mkm^2? Extent or area?

I think the ice trend will continue to go down. An equilibrium that would avoid getting a BOE would be nice, but I find it very unrealistic.

I would prefer a real recovery, at least for some years, stalling the process, but if the question is just "Is it just inside or just outside the definition of a BOE?" (and I fear it will be exactly that) then I'd prefer the BOE.

5
Arctic sea ice / Re: The 2019 melting season
« on: August 14, 2019, 10:21:15 PM »
Looks like a GAC hit the markets today. DJIA melted nearly 3%.

I scurried over to the Glossary before I got that. :-[ Well played, if not OT.  :)
I found "Diakonisches Jahr im Ausland" (for young Lutheran volunteers).

6
Arctic sea ice / Re: When will the Northwest Passage "open" in 2019?
« on: August 14, 2019, 12:10:37 PM »
Go then!!!! Hahaha, you are funny... a real picture with a resolution of a boat ??? From space?? D-K is fully strong in you....
Ummm... are you aware that on pictures from satellites you don't just see cars which are smaller than boats, you can even see the thinner markings separating parking spaces?

7
Arctic sea ice / Re: The 2019 melting season
« on: August 14, 2019, 09:40:55 AM »
Any idea why developments in NSIDC extent and JAXA extent have been diverging this week?

8
Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« on: August 09, 2019, 09:49:21 AM »
ASKING FOR A FRIEND


Why did CO2 go up during the interglacials over the last 800,000 years?

The release of stored CO2 can be both a cause and an effect of global warming.

As for the interglacials, they were started by the Milankovic cycles. Regularly, the changes in Earth's orbit and axial tilt lead to conditions in which high latitudes in the Northern Hermisphere - where there are continents that warm quicker than oceans - get a maximum amount of energy which starts a strong melting.

This melting then starts to set free stored CO2 (and also adds more water vapor to the atmosphere, which is also a greenhouse gas), which makes the melting stronger.

This melting lasts for thousands of years. During this time, the phase of optimal conditions in the Milankovich cycles has already ceased, and the process is no longer driven by them.

Eventually, the warming stops due to a new equilibrium. And since the conditions are no longer the optimal ones, a very slow cooling begins during which CO2 is stored away again. But this storing away takes a much longer time than setting it free. So after the melting at the start of the interglacial, we've had thousands of years of extremely slow cooling, and it was so slow that human civilisations developed their agriculture in this relative stability.

So the greenhouse effect of CO2 did not start the interglacial, but it kept it going long after optimal conditions has passed.

9
Arctic sea ice / Re: The 2019 melting season
« on: August 09, 2019, 09:13:06 AM »
Would that be the West Russian Low moving to the NP?

10
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: August 06, 2019, 07:35:43 PM »
In Wipneus' list in #1968, NSIDC area was on 13th place and extent in 23rd with data from July 31st.

Now area is still in 13th, but extent is now in 14th.

11
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: August 02, 2019, 06:39:54 PM »
That would be rank #20 in Wipneus' list in #1968, jumping 3 ranks in one day.

12
Is there a warm current going north just west of Svalbard, and if so, what happens to this water when it melts ice and cools? (Would it sink to deeper layers?)

13
Arctic sea ice / Re: The 2019 melting season
« on: July 24, 2019, 08:29:03 AM »
With low-concentration ice extending to the pole and the ice in general thin enough that an icebreaker could run through at full speed without taking damage. 
My climate-skeptical friends are pointing out that the Norwegian "Kronprins Haakon" had to return from a planned trip to the North Pole.
https://www.arctictoday.com/for-norways-newest-icebreaker-its-almost-to-the-pole-and-back/
Report says 'decided to turn back after meeting first-year ice measuring up to 1.5 meters thick, patches of multi-year ice and little sign of thawing.' halfway from Svalbard to north pole.  Latest PIOMAS shows volume at record low, and thickness from Svalbard to pole starting near 1m and increasing to about 2m.  The article claims the sea was built to run through ice up to 2 meters.
What I had meant with the icebreaker going full speed with no problem was at the time of the minimum. According to PIOMAS, the ice volume in Mid-July was just below 9000 km^3, and at minimum it will be about half of that. (A lot of extent with lose ice thickness completely, but even the region around the North Pole will see a further reduction in thickness)

14
Arctic sea ice / Re: Latest PIOMAS update (July 2019)
« on: July 23, 2019, 03:28:10 PM »
Gerrit,
I think the increasing fragmentation of Arctic sea ice, even in the CAB, is playing a major role as well, as it increases the surface open to melting.

15
Arctic sea ice / Re: The 2019 melting season
« on: July 17, 2019, 11:01:48 PM »
Neven,

I'm really sorry. Take as much time as you need, and don't force yourself to return. This is a painful time, and we'll all understand that you can't just start working on ASIF again as if nothing had happened.

16
Arctic sea ice / Re: The 2019 melting season
« on: July 15, 2019, 12:05:28 AM »
I don't want to see too much discussion of BOE and its implications. I'm happy no one announced a BOE this year.
Neven: how likely do you think a "Broken Heart" would be? (With low-concentration ice extending to the pole and the ice in general thin enough that an icebreaker could run through at full speed without taking damage. We've had these conditions at least once, depending on how strict you are)

17
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 11, 2019, 03:42:23 PM »
As the CAA has seemed to be holding well so far, is the current area loss in the data real, or is it an illusion caused by melt ponding?

18
I'm not sure if we currently have an active transpolar drift, pushing Fram export. Which sources and graphs would be best to consult?

19
Arctic sea ice / Re: The 2019 melting season
« on: July 04, 2019, 11:05:47 AM »
That is not a real chart of july 3rd. It would mean a BOE within two weeks.
It's not the real thickness. It merely shows how easily the ice will melt (which may still be thick). And it seems right now pretty much every place is vulnerable.

20
Arctic sea ice / Re: The 2019 melting season
« on: July 04, 2019, 12:30:12 AM »
It seems like if the northern CAA eventually would melt this year, there's be no solid ice being pushed in from the north to fix it. Which would mean yet another region added to the list of bad preconditionings...

But things could still change during the melt season, letting thicker ice drift back to the CAA region.

21
Arctic sea ice / Re: The 2019 melting season
« on: June 28, 2019, 07:52:43 PM »
<snip>
So, agreed on the centrality of data.  But I think it is not just fine, but scientifically healthy to make well-reasoned, thoughtfully calibrated predictions.  And if some of those don't turn out to be 'true', that is the way it is with predictions and we are still actively learning ...
I agree, it's scientifically important to continuously test models and prediction to see which ones work best, and possibly which factors played a role in it. This doesn't mean the ones we have right now are bad, but that they can still be improved.

22
Arctic sea ice / Re: The 2019 melting season
« on: June 28, 2019, 05:35:08 PM »
Ummm... I have a question about the discussion of when we should pay attention to data or prediction. Shouldn't we pay prime attention to the present when considering new record bad conditions?

It seems to me that predictions are nice to have, but it's not like they're actual data, and it's also not like we could avert anything by knowing the prediction a few days in advance. And predictions that fail to manifest seem to harm credibility.

On the other hand, looking at data afterwards often comes with comments like "it was bad, but it's getting better now". Gee, usually a new record is followed by a reversal to the mean. But that doesn't mean everything is well, because it's a decreasing mean which means just the regular up and down WILL bring new records, we're just not sure exactly when.

So I think one should look at the present, and note the records. And every new record is more evidence that there can be no true recovery unless the causes for the crisis change.

23
Arctic sea ice / Re: The 2019 melting season
« on: June 26, 2019, 03:24:30 PM »
And the last few winters were at worst bad for freezing, and at best they couldn't reach a level of regeneration that could turn thin, fragmented ice to the solid ice that was the rule a decade or two before.

In the end, the question is, would we continue to be lucky to not get a strong melt season until the ice returns to its previous levels, or would we get a new record low instead. Unfortunately, the second option seems way more likely.
Sorry for double post and kinda off-topic, but this one made me **really** curious! Dear AmbiValent, would you very kindly tell us here, what exactly makes you think that "ice returns to its previous levels" situation would actually happen in any observable future? I have a guess, but i'd really like to hear what you gotta say. And if you'd prefer not to answer this question - then please say so. It'd be hint enough in itself. Thanks!
I thoght I was clear that a new record is far more likely than a return to previous levels, given the last few bad winters.

Edit: From one year to the next, there might be gains, but I don't think the gains would continue until previous ice volume levels are reached. Losses are more likely to win in the end.

24
Arctic sea ice / Re: The 2019 melting season
« on: June 26, 2019, 02:47:25 PM »
And the last few winters were at worst bad for freezing, and at best they couldn't reach a level of regeneration that could turn thin, fragmented ice to the solid ice that was the rule a decade or two before.

In the end, the question is, would we continue to be lucky to not get a strong melt season until the ice returns to its previous levels, or would we get a new record low instead. Unfortunately, the second option seems way more likely.

25
From the looks of it, the volume of the sea ice is badly distributed - instead of a solid block, thicker ice appears to be closer to the edges where thin ice melting will leave the thicker ice open to melting from all sides, plus breaking up. But the melt season is still ongoing... well, hindsight is always 2020 as they say.

26
@Wipneus:

You uploaded the new data here, and gave it to Neven, but the last upload to Arctic Penguin had the data only to the end of March 2019. (Or do you consider Arctic Penguin obsolete now?)

27
@Wipneus: Thanks a lot. The data at Arctic Penguin still has the values from the end of March.

28
Arctic sea ice / Re: The 2019 melting season
« on: May 16, 2019, 02:32:54 PM »
By eyeballing, floe size in the Beaufort seems smaller than in 2016, which would be bad for the ice. But is there an official account of this?

29
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: January 30, 2019, 10:20:21 AM »
JAXA ARCTIC EXTENT 13,474,856 km2(January 29, 2019)

Was there a sensor error on 27th Jan ? The 79k increase on that day was not that unusual

Yes, it was showing as grey "lack of data" in the images of that day.

30
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: January 29, 2019, 12:16:57 PM »
Is the data the two-day average? Then the one-day error data will affect both days' published values, but the 28k increase would be real, since it exchanged a day with error-less data with another such day. And tomorrow the error should be gone completely.

31
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: January 28, 2019, 08:16:28 AM »
This abnormal increase, could be a problem with the sensor today?
Last time, grey areas were counted towards extent, so I think that abnormal increase isn't actually there.

32
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: December 21, 2018, 11:21:57 AM »
I thought, when this happened before, it was solved with the corrected data in a solid line in the main graph, but a dotted line remained showing the originally given data.

33
Arctic sea ice / Re: Latest PIOMAS update (mid December update)
« on: December 19, 2018, 08:47:54 AM »
@Wipneus
It seems you gave the new graphs from beginning of November on to Neven, but not on your arctic penguin page, where the last data is from back then.

34
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: December 18, 2018, 06:52:09 AM »
Uni Bremen, using AMSR2, shows a clear picture now, unlike yesterday.

35
Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« on: December 03, 2018, 09:10:09 AM »
Has the current back-and-forth between periods of rapid ice growth and near standstill always been there (just with more ice), or is it a result of climate change, maybe via weakening the jet stream allowing warmer air to get to the polar region easier?

36
Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« on: November 05, 2018, 03:26:23 PM »
Is there a name for the process in which a tropical cyclone becomes an extratropical one and later a polar one?

And is this connected to heat transport towards the North Pole, or is that rather caused by a specific arrangement of a number of pressure systems, and is there a name for such an arrangement?

37
Arctic sea ice / Re: The 2018/2019 freezing season
« on: November 01, 2018, 09:55:06 AM »
Oscar headed for the polar cell as extratropical cyclone.  GFS responds appropriately.
Is there even a name for such tro-polar cyclones?

38
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: October 18, 2018, 10:41:25 AM »
[ADS-NIPR (JAXA)] ASI Extent.

October 17th:
   2018: 5,772,608 km2, a small drop  :o of -8,089 km2.
   2010's Avg.: 6,490,722 km2, an increase of 121,730 km2
   
2018 is now the 3rd lowest on record.
2018, which has been argued safely away from breaking records, is now below 2012, and just 130k away from the record. We're NOT out of the woods yet.

39
Arctic sea ice / Re: Latest PIOMAS update (October)
« on: October 11, 2018, 03:29:32 PM »
It could be a problem if heat is getting pumped into the Arctic. The winter 2016/17 broke volume minimum records for months, and 2017 dodged a cannonball where it had a long period of less than average melting.

40
Arctic sea ice / Re: The 2018/2019 freezing season
« on: October 08, 2018, 05:41:47 PM »
Is the ice in Fram Strait right now old ice or newly frozen ice?

41
Arctic sea ice / Re: The 2018/2019 freezing season
« on: October 06, 2018, 11:28:22 AM »
October 1-5.
It's amazing. We are into October and the inner basin refuses to seriously freeze anywhere. The only growth is occurring in the Greenland Sea and the Beaufort export terminals. The only real freezing is occurring in the sheltered CAA. Hopefully this will soon be over, but it's still disturbing.
Could it be said that the freezing itself would be on schedule if changed atmospheric and ocenanic patterns wouldn't just keep on pushing in heat essentially from outside the Arctic? (Which in earlier times would have remained outside the Arctic)

42
Arctic sea ice / Re: The 2018/2019 freezing season
« on: September 26, 2018, 07:58:36 AM »
Does the near-zero mass balance right now mean there's already freezing on the Canadian side and in the Central Arctic Basin, but still melting on the Siberian side?

43
Arctic sea ice / Re: Latest PIOMAS update (August)
« on: August 05, 2018, 01:38:35 PM »
Re my previous post.  Could this just be down to less ice being available at (presumably warmer) lower latitudes at the end of the season?

If I read correctly there was less volume loss from this point in 2012 than the 80's average, despite the final volume being so much lower.
I think you've got it. The earlier ice melt in the periphery has gotten faster because peripheral ice is increasingly preconditioned to be thin and broken up - because that was how it ended up in the previous melt season. And such preconditioned ice, once broken up again, offers a much larger surface to the melt, and so melts faster than the thick ice there used to melt in the 80s.

And this means that later in the melt season when the insolation for melting is decreasing, there's much less easy ice on the periphery, and the ice in the Central Arctic Basin, where the insolation is decreasing fastest, is available but much harder to melt.

44
Arctic sea ice / Re: What the Buoys are telling
« on: September 04, 2016, 10:51:58 AM »
It's a good bit above the water surface. Also, the clouds aren't closed even in the foreground, so I'm pretty sure those are sunlit clouds.

45
Arctic sea ice / Re: The 2016 melting season
« on: August 26, 2016, 11:18:50 AM »
I think the ice motion in the Uni Bremen map looks more like transpolar drift. Some real compaction will likely happen when high pressure dominance over the ocean returns.

46
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: August 25, 2016, 09:47:24 PM »
Area is now below 2007 minimum and barely above 2011 minimum. Second place is almost guaranteed.

47
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: August 01, 2016, 07:15:22 PM »
Hmm... how to put it best? In the "old Arctic", Fram export was when ice was pushed through Fram Strait by Arctic currents. Sometimes there were stronger currents through the Fram, sometimes currents went into other directions, preventing the ice from leaving. And sometimes the ice could even get stuck when the whole width of Fram Strait was filled with ice.

In the "new Arctic", this "getting stuck" wouldn't happen anymore. The currents that sometimes go right through the Fram and sometimes into other directions are still there. That should improve Fram export.

But there's yet another new development working against it, which is warmer Atlantic currents meeting the ice front when it is still north of the Fram, melting ice right there. That ice would most likely have gone through the Fram and melt south of it, but now it won't be counted into export since it never passed Fram Strait.

Maybe we need a more complicated metric than the simple one we had used in the past to catch the new developments along the Atlantic-Arctic ice front...

48
I chose "one bin above 2012" for both polls.

49
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: July 31, 2016, 10:06:58 PM »
I don't think there is a chance for ice to be below 1M this year. Maybe below 3M (unlikely, thankfully), but I now guess it's somewhere between 3,25M and 3,5M. (I had feared it would be a new record low earlier this year, though)

Oops, with 1M you clearly meant 1 meter thickness in this region, not 1 million square kilometers extent or area. Sorry.

50
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: July 24, 2016, 09:21:38 AM »
I think the heat is baking my brain, making me stupid... so you do use UH SSMIS values not only in that graph, but your daily posted area value also used that as comparison for 2012?

Pages: [1] 2 3