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Messages - Thomas Barlow

Pages: [1] 2
1
Arctic sea ice / Re: The 2017 melting season
« on: May 26, 2017, 03:42:29 PM »
Looking only at the Arctic basin (instead of overall extent or thickness for the Arctic Circle and beyond) using DMI, I think it's fair to say that the icepack is not as robust this year as last year.

2
Arctic sea ice / Re: The 2017 melting season
« on: May 25, 2017, 03:22:20 PM »
]If Nares does not block up, what happens?
https://media.giphy.com/media/l0IycQAX8BRdZcIQE/giphy.gif

3
Arctic sea ice / Re: The 2017 melting season
« on: May 23, 2017, 03:52:50 PM »
The people saying that the ice is breaking up in smaller blocks appear to be right.
Was the winter freeze, with all its anomalously warmer temps., only enough to cement small, broken-up blocks together, rather than create any significant new thickness or extent, creating an illusion of relative stability in area?
"""Polar bear scientists see unusual sea ice breakup""
http://www.ktuu.com/content/news/Polar-bear-scientists-see-unusual-sea-ice-break-up-423713633.html

4
Arctic sea ice / Re: The 2017 melting season
« on: May 22, 2017, 10:01:30 PM »
Where did it go?
Charts show this ice that's now  entering Nares to be old thick ice, but the way it crumbles makes for doubt. 5-21 vs. 5-22
i was just looking at that.
The ice is being reported as 4-5 m thick ice, but is being pulverized as it enters the Nares. Seems surprising. 

5
Arctic sea ice / Re: The 2017 melting season
« on: May 21, 2017, 08:20:47 PM »
Can you point me to the site? (worldview)

---> http://tinyurl.com/nykf7bz

6
Permafrost / Re: Arctic Methane Release
« on: May 21, 2017, 06:27:55 PM »
Surges of algae growth in the summer may be followed by high emissions of methane and CO2 in the fall. I don't dispute what this study observed but the scientists should be very careful not to extrapolate a summer bloom with reductions in CO2 and methane emissions. Several studies over the past several years have found unexpectedly high releases of CO2 and methane in the fall when sunlight is gone but temperatures are still pretty warm and ice is thin or not present.
The jury's out, but would the high releases of CO2 and CH4 in the Fall be enough to cancel out the Summer's "1900 times more CO2 being absorbed than methane being emitted" as the study suggests? One would have to compare tonnage.
Although methane is a much worse GHG in the short-term, so then you would have to figure out if "1900x" is enough to compensate for any balance of the scales on year-round Arctic methane release to the atmosphere.

Maybe nature has its own 'carbon credits' system?

7
Arctic sea ice / Re: The 2017 melting season
« on: May 21, 2017, 06:18:10 PM »
All the ice between the Beaufort and Chukchi is starting to break up.
A close up look.

A lot of peripheral regions seem to be disintegrating now. Including the Lincoln Sea, which is unusual (maybe unique). Because of its position in the jigsaw puzzle, it could be the straw that breaks the donkey's back. (I hope not.)

8
Arctic sea ice / Re: The 2017 melting season
« on: May 19, 2017, 04:48:25 PM »
TB - Wipneus tracks grpahs or Arctic Basin area and extent, which excludes all peripheral seas but includes the seas adjacent to the CAB. I think this is what you are asking for.

Thanks to everyone for pointing me to the CAB charts. I'm bookmarking all of these.
This one seems to be showing 2nd lowest in recent years right now (with that weird, but unsustained dip in 2016 beating it out).

9
Arctic sea ice / Re: The 2017 melting season
« on: May 19, 2017, 05:15:28 AM »
Beaufort joined to Nares?

10
Arctic sea ice / Re: The 2017 melting season
« on: May 18, 2017, 02:33:55 PM »
I saw this surprising chart on Jim's site. I didn't think 2017 was tracking 2016 in this region, was quite sure it was lagging.

Compare and contrast. Beaufort open water is behind last year, balanced by Chukchi & ESS ahead of last year:

Is there a graph (comparing years) that takes out the CAA and everything else that is not really in the Arctic Ocean?

11
Arctic sea ice / Re: The 2017 melting season
« on: May 17, 2017, 03:51:00 PM »
"Is there any significant MYI left in the Lincoln Sea?"
Yes, but it's more like ice clinging to land at this point, rather than significant part of the icepack
will the apparently thinner stuff coming into the Nares strait and eventually to Baffin Bay be easier to flush out ?
Nobody knows. I was trying to see how that would go. If you look at the ice thickness map over time, it looks like thick ice is being sucked down that drain (the Nares), and thinner will follow it. And with SSTs higher than the norm., I suspect it will flush through.

12
Permafrost / Re: Arctic Methane Release
« on: May 15, 2017, 06:29:12 PM »
There is emphasized the relationship of 1:2000 - one part upwelling methane could trigger the photosynthesis uptake of 2000 parts CO2...That the photosynthesis in the end is only doubled compared with the water enviroment is not said exactly.
Doubling the photosynthesis causes 1:2000 ratio is the point I think.

I don´t believe the algae will be a real sink for carbon - most of them don´t sink down and as a lot of fishes and other marine life is extremely threatened
Fishes, seaweed, sharks, and whales take on carbon as cleaners of the oceans. That's their job. An extra bit of carbon won't hurt them, or anyone who eats them. The biggest problem there is the over-fishing of the ocean, and also plastic particle soup in the ocean, turning them acidic. Also Fukushima could be bad. Also pollution dumped directly into ocean by cities and international shipping. And, of course, the oceans do absorb carbon from the atmosphere, so become more acidic.

That the algae effect will not work in dark winter is also not told by GEOMAR-also it is transfered to areas with shallow waters... It is even told that methane is not proven to cause the upwelling of nutrisious waters-in contrast to Sciencemag article.
They did say it in the article about the dark winter (at the very end). The whole fear of melting icepack is that in the summer it could lead to more methane release. In the past, the large summer icepack would trap methane before it is released, and it was quickly absorbed by natural mechanisms. Now, that icepack is more and more open in summer, shallow seabed regions more likely to melt. As far as I know, winter is not as big an issue, due to icepack cover over the Arctic Ocean (except in land permafrost maybe).

The jury's out on this effect, maybe it needs to be included in modeling to see what happens, but if the methane sensors are correct, the methane is rising as far as I can tell.

Another interesting effect I saw ---> https://scripps.ucsd.edu/news/biological-activity-found-affect-aerosols-produced-sea-spray

Maybe Gaia is real.



13
Arctic sea ice / Re: The 2017 melting season
« on: May 14, 2017, 04:26:41 AM »
I keep wondering: will the debris from this breakup clog Nares Strait or will it just flush through? So far, it is flowing smoothly.
I was wondering about that, and I suppose higher SSTAs that can be seen, may make a smooth passage more likely if they are the norm.

14
Permafrost / Re: Arctic Methane Release
« on: May 13, 2017, 12:02:25 AM »
What happens to the algae though? Does it actually sequester the carbon by dying and getting buried by silt at the bottom of the ocean or just die and decompose in the water column? If it does that, then this is just a roundabout way of adding carbon to the carbon cycle.

I believe it sinks. Also, it takes bacteria with it. Other creatures will eat it and (later) die and sink.

PS.Whales are considered large carbon sinks too, both in their effect as they have to rise near the surface to deficate, which creates algae, and the same CO2 sequestration effect.
 Also, churning the lower and upper layers.
They also take on a large amount of carbon, and when they die. they (usually) take that to the bottom of the sea as well, and the rotting carcass acts to create more biological activity that sequesters carbon for decades.
https://en.wikipedia.org/wiki/Whale_fall
Therefore ... Save the Whales.

15
Permafrost / Re: Arctic Methane Release
« on: May 11, 2017, 11:57:14 PM »
;D wish I would have some more time to dig in-but I think it is not worth it. Intention seems to be to spread doubts and to give the mainstream media with the Sciencemag article stuff to tell some good news about methane.


That was my first reaction, but it seems legit science, and I doubt there is any "intention" here.
They are just doing a scientific experiment and getting it published, like any other scientists. They state that it is small-scale.
It's published in PNAS.
http://www.pnas.org/content/early/2017/05/02/1618926114
However, I do agree that it seems unlikely that this algae effect would slow the observed methane rise. Perhaps in the shallow ocean, yes, I could see that.
Perhaps "Slow the rise of global warming a little" should have been emphasized more. Especially since it is just one small experiment.
And I can't see it happening in the permafrost on land. However, there may be other factors at work in the permafrost that could slow the release from being 'catastrophic'.
Unlike many, I am open to being wrong about the dangers of methane (a view which I have supported for years) if more research is done, I will change with the science, if it is legit.
And the researcher did state that this only applies to daylight-time in the Arctic, not the night of winter.

There is no question in my mind that the increase in algae could naturally sequester CO2 and slow warming, but enough to make a real difference to global warming? ... I can't see that happening unfortunately.

Juries' out on this I think. Time, and more experiments will tell.
However, monitoring shows Arctic methane continues to rise:
https://www.esrl.noaa.gov/gmd/dv/iadv/graph.php?code=BRW&program=ccgg&type=ts(

16
Permafrost / Re: Arctic Methane Release
« on: May 11, 2017, 05:21:34 AM »
"Are methane seeps in the Arctic slowing global warming?"
http://www.sciencemag.org/news/2017/05/methane-slowing-global-warming-arctic

19
Arctic sea ice / Re: The 2017 melting season
« on: May 10, 2017, 06:59:45 PM »
SST and SSTAs seem pretty high in Chukchi sea.
How will this impact that area as the season progresses?

20
Arctic sea ice / Re: The 2017 melting season
« on: May 07, 2017, 04:11:49 AM »
It seemed to me like 2008 had relatively thin ice in May, and not record setting low volume in September?
Although 2008 had a lot more reds and pinks than current.
Don't know if that made a difference. Seems unlikely, since they are crunched against CAA mostly.
I am not expecting record setting low area in September, based on this, but close.
(I'm using May 2, because DMI seems to be stuck on May 2 right now.)

(ice just above 1.5m thick)

22
Arctic sea ice / Re: The 2017 melting season
« on: May 06, 2017, 09:13:25 PM »
Looking at these comparisons from DMI and Hycom I'm having some thoughts:
* Obviously thickness in early May is not a very good predictor of location of remaining ice in September. I guess movement during the season is a large part of that.
* Some might be explained by latitude, as ice below 80 deg has a lower chance of surviving for a given thickness, while ice at 85 deg on the Atlantic side may still thicken more during May.
Hard to predict, yes. Here is the movement, month to month, for 2016. Always ends up clumping up against CAA and Greenland.
https://media.giphy.com/media/3og0IGrFYUSA6F65dC/giphy.gif
* Some might be explained by model inaccuracies, as DMI is not known for its good volume estimates. Maybe a PIOMAS cutout of current date in 2016 vs. remaining ice at min 2016 could shed some more light or expectation for this year, though it seems there is just not enough information yet.
It would be interesting to put a DMI graph and a HYCOM graph with the 2016 annual curves together on one chart, adjusted for graph scales, and include one or other of their 'margin of error' ranges. I think they would both seem pretty similar compared to the margin of error. I think there are none of them that super-accurate, and I very much doubt the US navy, since they are only concerned with places a ship could get through. I doubt they are too concerned with great accuracy. I take all of the systems as just rough estimates really.
* The Hycom comparison for the 2.5m ice in 2017 compared to 2015 and 2016 is shocking.
It is pretty wild looking.

23
Arctic sea ice / Re: The 2017 melting season
« on: May 06, 2017, 04:05:52 PM »
Here is just over 1.5m thick ice for May 2, 2016, alongside Sept. 15th 2016 minimum.
Below that is May 2, 2017, with just over 1.5m thick ice.
The 1.5m+ version does seem closer in area at first glance, since the 2m+ version seems too small an area when comparing the 2016 May and Sept. (area) versions (because of how the area tends to move towards the Atlantic side eventually.)

24
Arctic sea ice / Re: The 2017 melting season
« on: May 06, 2017, 03:53:45 PM »
So I would say 2.5m thick ice is also surely vulnerable, depending on latitude and mobility, possibly even thicker than that. If you put the May map side by side with the same map at the Sep min, some more insights might arise.
Here is just over 2m thick, and below that, just over 2.5m thick, for May 2.

25
Arctic sea ice / Re: The 2017 melting season
« on: May 05, 2017, 05:58:05 PM »
Here I took out everything about 1.75 meters thick and compared it to 2016.
Looking at just the main area of the Arctic Basin here.
If you think of yellow (3m thick) and yellow-green, as showing robust state of Arctic Basin, then 2016  maybe looks more spread out across the icepack than today (as well as thicker reds (5m) in 2016).
In terms of melting, has a certain thickness in early May been generally observed to survive the summer melt? I'm guessing 1.5 meters is vulnerable (putting aside concentration for a minute here, since a lot of 3m ice is usually pretty concentrated.)

26
Arctic sea ice / Re: The 2017 melting season
« on: May 05, 2017, 05:40:32 PM »
Stunning aprupt upwards movement of the Extent Graph of Bremen...  :o

In this region it looks like the channels in the CAA, and the Fram/Atlantic, as well as the Nares Straight have more extent than 2016 for example. I wonder if that adds to it? Fram could be mostly export. Nares and Fram could be Greenland melt, freshwater that cools the surface (floats on salt water, and is cooler, and also freezes more easily). But I think it is mostly export.

27
Arctic sea ice / Re: The 2017 melting season
« on: May 04, 2017, 03:32:38 PM »
Not sure which thread to post this in, but is this unusual? Is it relevant to Arctic?
Today's jet stream:
https://media.giphy.com/media/xUPGcoh39ZKjSAlIju/giphy.gif




(from: https://earth.nullschool.net/#current/wind/isobaric/500hPa/orthographic=-62.81,40.95,555 )

28
Arctic sea ice / Re: The 2017 melting season
« on: April 29, 2017, 02:25:53 PM »
Interesting graphic, really looks like where ice is close to 100% concentration it's thinner and areas with thicker ice are more fractured.

My take on it is that there are areas of thick, concentrated ice, and thinner ice. The Beaufort, for example, is relatively thick and relatively concentrated at this time compared to the main area of weakness which is towards the Russian (east) side, where the blue areas are thinner and less concentrated, and the intrusions of blue into the thicker areas should be note for concern, since those look more advanced than usual.  It's early days yet, but still gives an overall sense.

29
Arctic sea ice / Re: The 2017 melting season
« on: April 27, 2017, 02:01:05 PM »
This mixes (colors) concentration with sea-ice thickness maps, so the blue areas (not deeper purples, or reds and blacks) show where the vulnerability is, being both thinner, and slightly lower concentration. Reds, blacks, and deeper purple, show thicker, more concentrated ice.

30
Arctic sea ice / Re: The 2017 melting season
« on: April 26, 2017, 05:44:23 AM »
It might be interesting if they didn't include the years from 2010 onwards in their "Mean Volume".

Does anyone have the data skills to create such a chart? ... with only 1979-2010 included for the average (black-dotted line).
It would be interesting to see the difference in the chart, caused by the last several low-volume years.

Here's a crack with a line for 1979-2010 added.

We'll see what September 2017 brings us, but it seems clear that there is a good chance that we are about to find out if the Arctic summer melts ice 'volume' or if it melts 'extent'.
I'd guess both. If less thick ice becomes the norm, as it may be heading for this year, then more open areas by August 1st are likely. After that, extent could drop precipitously.

31
Arctic sea ice / Re: The 2017 melting season
« on: April 25, 2017, 12:20:51 AM »
It might be interesting if they didn't include the years from 2010 onwards in their "Mean Volume".

Does anyone have the data skills to create such a chart? ... with only 1979-2010 included for the average (black-dotted line).
It would be interesting to see the difference in the chart, caused by the last several low-volume years.

Here's a crack with a line for 1979-2010 added.
Ok, not a huge difference, but thanks for doing that !
Interesting to see.

32
Arctic sea ice / Re: The 2017 melting season
« on: April 24, 2017, 11:48:36 PM »
It might be interesting if they didn't include the years from 2010 onwards in their "Mean Volume". Including those just makes the average descend down the chart each year, and gives a false impression, because the most recent years are lowest on record, and declining more as we speak. The average from 1979-2010 would be much higher up on the chart, and it would show we are in a precipitous decline in the last 5-7 years, at least compared to the average of modern records.

Does anyone have the data skills to create such a chart? ... with only 1979-2010 included for the average (black-dotted line).

I suspect a certain flightless bird with a drippy nose could crank that out.  He's already doing other charts with the PIOMAS data. 

Let me add, I think that's an excellent idea.  Moving the goalpost is hardly ever a good idea.
Who?
(who is the flightless bird. Can he do it?)

33
Arctic sea ice / Re: The 2017 melting season
« on: April 24, 2017, 11:46:41 PM »
Interesting.
According to this - http://polarportal.dk/en/havisen-i-arktis/nbsp/sea-ice-extent - a lot of 5m thick ice off Ellesmere island & Greenland, but open water in channel. Strange.

34
Arctic sea ice / Re: The 2017 melting season
« on: April 24, 2017, 11:34:13 PM »
Interesting.
North Pole ice is 2.75m thick, whereas it was 4m+ thick this time last year.
No wonder Barneo did a retreat.
http://forum.arctic-sea-ice.net/index.php/topic,1905.msg111027.html#msg111027

35
Arctic sea ice / Re: The 2017 melting season
« on: April 24, 2017, 11:19:45 PM »
A year on year look at the Beaufort. Far less cracks. Give it time though I suppose.

According to this, it is much thicker in the peripheral Beaufort than last year.
(but thinner elsewhere in the Arctic this year, than 2016)

36
Arctic sea ice / Re: The 2017 melting season
« on: April 24, 2017, 03:27:42 PM »
It might be interesting if they didn't include the years from 2010 onwards in their "Mean Volume". Including those just makes the average descend down the chart each year, and gives a false impression, because the most recent years are lowest on record, and declining more as we speak. The average from 1979-2010 would be much higher up on the chart, and it would show we are in a precipitous decline in the last 5-7 years, at least compared to the average of modern records.

Does anyone have the data skills to create such a chart? ... with only 1979-2010 included for the average (black-dotted line).
It would be interesting to see the difference in the chart, caused by the last several low-volume years.

37
Arctic sea ice / Re: The 2017 melting season
« on: April 23, 2017, 01:33:13 PM »
I just added " >1.5m " ice to the bottom of my post on previous page (18), re. ice thickness in the Arctic Basin 2016 vs 2017.
Even more interesting.
Unfortunately, it's not looking very robust.

Click here, scroll down ---> https://forum.arctic-sea-ice.net/index.php/topic,1834.msg110856.html#msg110856

38
Arctic sea ice / Re: The 2017 melting season
« on: April 22, 2017, 11:28:51 PM »
This compares thickness, for certain thickness ranges only.
Between 2016 and 2017.
(I'm guessing most sources out there are just approximate, with a wide margin of error?)

39
Arctic Background / Re: Barneo 2017
« on: April 22, 2017, 03:52:02 PM »
Did these camps used to last longer into April/May?

40
Arctic sea ice / Re: The 2017 melting season
« on: April 22, 2017, 03:25:28 PM »
On the left 21 April 2012, and on the right 20 April 2017.

2012 was not particularly thin ice (compared to other recent years) in mid-april.  Yes, whatever weather condition cleared the ice out in 2012 re-occurs in 2017, the ice is going to have a big problem.  2011 and 2016 might be better comparisons for relatively thin ice in April and a low extent in September?
Here is the comparison for 2016 .
Are there any charts that try to gauge thickness or volume for just the main Arctic Basin?
All the charts take into account all the channels and east Greenland, and may not say much about state of main Arctic Basin icepack.
( I took out the thick ice that is pushed up against land masses, as I think some of that would be there anyway, even in a future meltdown, and doesn't tell us too much about the state of the overall icepack in the Arctic Basin. And I took out ice in channels and Fram export, as those are not really part of the main state of the Arctic basin icepack)
I'd say 2017 looks in worse shape than 2016?

41
Arctic sea ice / Re: The 2017 melting season
« on: April 21, 2017, 09:33:26 PM »
So much data saying Melt (DMI, Arctic anomaly, Fram export, destruction of  sea ice sheets integrity from multiple observations  etc. etc.). And yet jaxa sea ice decline remains at a glacial pace, and sea ice volume not declining yet.
And still at least 2 weeks before getting April PIOMAS  update. Am I the only one in confusion ?

I think the answer is dispersion, GC.  Less ice, spread more thinly.


AKA -- Winter Storms.

Does it make a difference if you just look at the main Arctic Basin?
Are there any charts that try to gauge thickness or volume for just the main Arctic Basin?

Here, below, I have taken out the thickest ice (4-5m) that clings, or is pushed against land mass. Some of that thick ice would probably still be there, even if the Arctic ever opens up in summer, as some say it will some day. And I also deleted most of the ice that forms in all the channels between islands.

A lot of that ice in channels, and the ice packed up against the land mass, could still be there even if the central Arctic Basin eventually starts to break up. So this may be a more realistic comparison, reguarding the major icepack, and reguarding what is essentially going on, that counts the most in assessing the state of the central icepack.

On the left 21 April 2012, and on the right 20 April 2017.

http://polarportal.dk/en/havisen-i-arktis/nbsp/sea-ice-extent/

42
Arctic Background / Re: Barneo 2017
« on: April 21, 2017, 02:53:26 AM »

43
Arctic sea ice / Re: The 2017 melting season
« on: April 18, 2017, 01:16:18 AM »

P.S. As visible from the forecast in the post just above, Scandinavia and much of North America landmasses are currently doing about the same thing, and will keep at it at even bigger negative anomaly than central Russia for the next few days: "stealing" cold from the Arctic, and warming all the air up extra fast whereever there is no snow cover already.

Same situation here in Tallinn, Estonia (900 km north-west from Moscow). By the way, this situation extends well into next week, latest temp anomalies Apr 18 - Apr 24 (GFS, Climate Reanalyzer).


Not good news.
Arctic seems completely overheated most of the time.
If the average temperature is still well below freezing, does it matter about winter anomaly in the short term? Obviously not a good indication for summer or long-term, but freezing is freezing, so does it make a big difference? Yet?

44
Greenland and Arctic Circle / Re: Meltwater & Run-off
« on: April 16, 2017, 05:42:06 PM »
Related study (from Greenland)

Molecular and biogeochemical evidence for methane cycling beneath the western margin of the Greenland Ice Sheet http://www.nature.com/ismej/journal/v8/n11/full/ismej201459a.html

And Antarctic permafrost highlights the history of biogeochemical activity in some Antarctic regions. Coastal Antarctic Permafrost Melting Faster Than Expected https://news.utexas.edu/2013/07/24/coastal-antarctic-permafrost-melting-faster-than-expected


Great !
I find this fascinating, and I think under-represented in the literature on ice-melt and the ecosystem it is unavoidably entangled with.

45
Greenland and Arctic Circle / Re: Meltwater & Run-off
« on: April 16, 2017, 04:39:31 PM »
An increase or decrease in algae will probably change the food chain in ways that might not be favorable to humans.

Maybe so.
I think a discussion of meltwater run-off and fresh-water on the ocean's surface is an interesting discussion at this point. Seems like scientists are looking at it more and more.

(If there is already a discussion specifically about meltwater and run-off, I can move this to that discussion.)

46
Greenland and Arctic Circle / Re: Meltwater & Run-off
« on: April 16, 2017, 04:01:01 PM »
Ok, this is where it gets tricky.
--> https://www.sciencedaily.com/releases/2017/04/170412105910.htm
.

Now there are microbes on surface and biological activity and minerals flowing into ocean. This creates photo-synthesis, absorbs carbon, also the bacteria and mineral-rich fresh water enriches ocean locally (a vast area actually). Increase in bioactivity and fauna, fish, whales. Increase in algae and plankton. All of that is good for the ocean (eg. N. Atlantic, Antarctic), nullifies acidity, and algae increases the ocean's ability to absorb CO2 and methane, as do bacteria which absorb methane.
All this is an unseen aspect, that scientists are just realizing (although they may be interpreting it in a limited way in this article), and may put the brakes on various abrupt climate-change scenarios going around.

More nutrients, algae, and plankton, in the ocean, as a result of fresh water, mineral rich run-off from glaciers, could improve ocean health, absorb carbon, nature could have surprises in store that can - as long as we stop polluting - stall, slow-down global warming. This article at the very least, proves that scientists are unaware of all processes. I think they have interpreted this as bad, but in fact, this could be good news.

But we have to stop polluting and mass factory livestock farming, slow population growth, etc.

47
Greenland and Arctic Circle / Meltwater & Run-off
« on: April 16, 2017, 03:55:21 PM »

48
Arctic sea ice / Re: Latest PIOMAS update (April)
« on: April 08, 2017, 05:14:05 AM »
Thomas,
I tried to answer part of your query on the "2017 melting season" thread yesterday. Click on the hyperlink associated with my name below...

Yes, thanks Bill, that's great info.


49
Arctic sea ice / Re: Latest PIOMAS update (April)
« on: April 07, 2017, 10:24:04 AM »
Neven asked me post this here instead:
____________________

Tried to post this to Neven's blog (didn't work). Any comments? :

What's really worrying is that they include recent years (mostly low volume years) in their 'mean volume 1979-2016'.
That means the black line will be getting lower each year, as recent years are added to the mean.
If they just used 1979-2000 (as Climate-Reanalyser does for temperatures), then the black line would be much higher up the chart (not that that period alone would be enough to show average though). What do the ice cores, taken from at least the 1970s, show, about the longer-term past of the Arctic?

http://neven1.typepad.com/blog/2017/04/piomas-april-2017.html

50
Arctic sea ice / Re: The 2017 melting season
« on: April 06, 2017, 04:35:50 PM »
Tried to post this to Neven's blog (didn't work). Any comments? :

What's really worrying is that they include recent years (mostly low volume years) in their 'mean volume 1979-2016'.
That means the black line will be getting lower each year, as recent years are added to the mean.
If they just used 1979-2000 (as Climate-Reanalyser does for temperatures), then the black line would be much higher up the chart (not that that period alone would be enough to show average though). What do the ice cores, taken from at least the 1970s, show, about the longer-term past of the Arctic?

http://neven1.typepad.com/blog/2017/04/piomas-april-2017.html
.

<Take it to the PIOMAS thread, Thomas,s'il vous plaît; N.>

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