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Author Topic: Latest PIOMAS update (August 2020)  (Read 1214386 times)

Nick_Naylor

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Re: Latest PIOMAS update (March)
« Reply #1350 on: March 03, 2017, 01:19:14 PM »
More than any previous year, it looks like all the thick ice is likely to export. Or could that just jam up the Fram so nothing gets out?

oren

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Re: Latest PIOMAS update (March)
« Reply #1351 on: March 03, 2017, 01:51:28 PM »
Chart of day 59 volume over they years, using Wipneus' calculated number.
Here goes Chris Reynolds' winter plateau, due to this year's dismal FDDs.
« Last Edit: March 03, 2017, 04:31:17 PM by oren »

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Re: Latest PIOMAS update (March)
« Reply #1352 on: March 03, 2017, 02:10:08 PM »
PIOMAS gridded thickness data has updated. From the thickness I calculate 18.609 [1000 km3] for day 59. That would be about 1850 km3 lower than the previous record for the day in 2010.

Thickness maps will be posted later.

Incredible if true. Unless 2017 somehow reverses, we're going to see things we haven't heretofore seen.

(Though don't you mean 2011, and not 2010?)


Wipneus

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Re: Latest PIOMAS update (March)
« Reply #1353 on: March 03, 2017, 02:17:22 PM »

(Though don't you mean 2011, and not 2010?)

Yes, I miscounted  :-[

Jim Pettit

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Re: Latest PIOMAS update (March)
« Reply #1354 on: March 03, 2017, 02:18:55 PM »

Yes, I miscounted  :-[
[/quote]

Lord knows I've never done that. ;-)

Thanks, as always, for all that you do, Wip.

gerontocrat

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Re: Latest PIOMAS update (March)
« Reply #1355 on: March 03, 2017, 02:20:02 PM »

(Though don't you mean 2011, and not 2010?)

Yes, I miscounted  :-[

If Wipneus starts miscounting, we are all DOOMED
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Re: Latest PIOMAS update (March)
« Reply #1356 on: March 03, 2017, 02:57:22 PM »
Those numbers alone are BAD.
Ice structure, location of remaining MYI is even WORSE.

Without any doubt the worst start for a Melting Season so far.
And there could still be surprises in store.


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Re: Latest PIOMAS update (March)
« Reply #1357 on: March 03, 2017, 03:30:08 PM »
As melt season progresses the ice in front of the thicker older ice above Fram will melt away leaving open passage for it to collapse into and drift out of the basin.

With so much less ice than last Feb and it seeing so much less FDD's what dare we expect for the ice come minimum?

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Re: Latest PIOMAS update (March)
« Reply #1358 on: March 03, 2017, 04:59:24 PM »
From day 59 to maximum volume the average gain is 2.103 x  1000km3

Attached is the chart for Max Volume - Volume at day 59.

Average volume gain from day 59 to max is 2.103.
Maximum Volume gained from day 59 to max is 2.707 in 1985
Minimum Volume gained from day 59 to max is 1.266 in 1990

Second graph is that of Max Volume - Min Volume.

The average volume loss is 16.907.
The Max volume loss was 19.693 in 2010
The Min volume loss was 13.925 in 1996




Edit

Worst case scenario: If we are at 18.609 with minimum volume gain from 59 to max of 1.266 we'll have a max of 19.875. If we also get the maximum volume loss then 19.875-19.693=0.182

Under some definitions that's an ice free arctic.

« Last Edit: March 03, 2017, 05:53:00 PM by Archimid »
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Re: Latest PIOMAS update (March)
« Reply #1359 on: March 03, 2017, 05:16:10 PM »
PIOMAS gridded thickness data has updated. From the thickness I calculate 18.609 [1000 km3] for day 59. That would be about 1850 km3 lower than the previous record for the day in 2010.

Thickness maps will be posted later.

Incredible if true. Unless 2017 somehow reverses, we're going to see things we haven't heretofore seen.

(Though don't you mean 2011, and not 2010?)
There was a while there that it looked like the volume wouldn't even make a high as it did.
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Re: Latest PIOMAS update (March)
« Reply #1360 on: March 03, 2017, 05:33:14 PM »

There was a while there that it looked like the volume wouldn't even make a high as it did.

If we see the ice from pole to Fram get a shift on you might still see low numbers by max? A big Greenie High and a near permanent low in the Baltic and that ice would be out of the basin in 3 weeks ;)
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Kethern

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Re: Latest PIOMAS update (March)
« Reply #1361 on: March 03, 2017, 05:54:20 PM »
From day 59 to maximum volume the average gain is 2.103 x  1000km3

Attached is the chart for Max Volume - Volume at day 59.

Average volume gain from day 59 to max is 2.103.
Maximum Volume gained from day 59 to max is 2.707 in 1985
Minimum Volume gained from day 59 to max is 1.266 in 1990

Second graph is that of Max Volume - Min Volume.

The average volume loss is 16.907.
The Max volume loss was 19.693 in 2010
The Min volume loss was 13.925 in 1996

So from those numbers:

If we have a perfectly average year we end up with a minimum of 3.805 x 1000 km3. And 2012 keeps its record by a hair.

Best case (maximum gain, minimum loss) ends with a minimum of 7.391, ok I think we all agree that is unlikely.

Worst Case (minimum gain, maximum loss) ends at 0.182  :o

Gray-Wolf

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Re: Latest PIOMAS update (March)
« Reply #1362 on: March 03, 2017, 06:01:27 PM »
I wouldn't recognise an 'Average' melt season any more if it hit me in the face!

All we can hope for is a low solar , high cloud.cool summer over the basin and that would still leave us in bad shape?

A high melt/export forcings summer just doesn't bare thinking on!
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jai mitchell

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Re: Latest PIOMAS update (March)
« Reply #1363 on: March 03, 2017, 06:25:11 PM »
it is looking closer to 3.15K on Sept 21 to me.
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Re: Latest PIOMAS update (March)
« Reply #1364 on: March 03, 2017, 08:49:40 PM »
With low volume and normal FDD from 28Feb to max, then we should expect above average gain by maximum, right? Maximum above 21.3 k km3 does not seem impossible to me.

But I would expect the volume loss to be high due to low ice volume at max. There is also an upward trend in volume loss so a volume loss of just 17 k km3 would be surprising.

So seems pretty likely to beat 2012 minimum record with only room for about 0.5 k km3 more than that in a reasonable best case.

Jim Pettit

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Re: Latest PIOMAS update (March)
« Reply #1365 on: March 03, 2017, 08:54:57 PM »
it is looking closer to 3.15K on Sept 21 to me.

It's too early for me to do this, but maybe everyone will forget by September: I will go out on a very short limb and (probably foolishly) predict a PIOMAS volume minimum between 1.8K and 2.2K.

jai mitchell

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Re: Latest PIOMAS update (March)
« Reply #1366 on: March 03, 2017, 10:17:10 PM »
With low volume and normal FDD from 28Feb to max, then we should expect above average gain by maximum, right?

That is my sense of it but I would not rely on just FDD, export and warmer SST intrusion may also be a factor in suppressing mass accumulation.  In addition, we need more than strictly normal FDD, we need large and sustained periods of high FDD to bring internal ice sheet temperatures down from their abnormal warmth.  This extra heat would work to suppress volume accumulation even with high FDD.
« Last Edit: March 04, 2017, 07:59:09 PM by jai mitchell »
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Re: Latest PIOMAS update (March)
« Reply #1367 on: March 03, 2017, 10:23:36 PM »
It's too early for me to do this, but maybe everyone will forget by September: I will go out on a very short limb and (probably foolishly) predict a PIOMAS volume minimum between 1.8K and 2.2K.

I believe in "state change", and I believe that 2017 is the transition year. So I predict a PIOMAS volume minimum between 0.8K and 1.2K.

jdallen

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Re: Latest PIOMAS update (March)
« Reply #1368 on: March 03, 2017, 10:28:09 PM »
From day 59 to maximum volume the average gain is 2.103 x  1000km3

Attached is the chart for Max Volume - Volume at day 59.

Average volume gain from day 59 to max is 2.103.
Maximum Volume gained from day 59 to max is 2.707 in 1985
Minimum Volume gained from day 59 to max is 1.266 in 1990

Second graph is that of Max Volume - Min Volume.

The average volume loss is 16.907.
The Max volume loss was 19.693 in 2010
The Min volume loss was 13.925 in 1996




Edit

Worst case scenario: If we are at 18.609 with minimum volume gain from 59 to max of 1.266 we'll have a max of 19.875. If we also get the maximum volume loss then 19.875-19.693=0.182

Under some definitions that's an ice free arctic.
It's very disturbing.  It's worth noting that even with the average loss of the last 7 years or so (about 18.5) that will put us under 2 million KM3.  Unless that ice is all 1M thick, we're flirting with under 1M KM2 of area, and looking at open water pretty much everywhere except hard up against the CAA and northern Greenland.
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Jim Pettit

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Re: Latest PIOMAS update (March)
« Reply #1369 on: March 03, 2017, 10:46:21 PM »
As with extent, PIOMAS volume has had the lowest average monthly measurement the last  four consecutive months (NDJF), and it's going to be very difficult for March to *not* be in first as well.

Anyway, this is crazy:



...as is this:


Wipneus

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Re: Latest PIOMAS update (March)
« Reply #1370 on: March 04, 2017, 08:19:55 AM »
I updated my graphics, see the top post

Attached my year-by-year anomaly graph showing the anomaly changed little, stayed strongly negative, during the past month.
« Last Edit: April 05, 2017, 06:51:14 AM by Wipneus »

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Re: Latest PIOMAS update (March)
« Reply #1371 on: March 04, 2017, 11:47:11 AM »
As with extent, PIOMAS volume has had the lowest average monthly measurement the last  four consecutive months (NDJF), and it's going to be very difficult for March to *not* be in first as well.

Anyway, this is crazy:

Jim, could you just explain this spiral plot please for those less familiar with it? It's 12 sectors, presumably one per month, and the clockwise end of each sector would be the last day of the month? So am I correct in thinking that the current update only has data to the end of Jan 2017 and that you (or whoever generates it) have not had a chance to update it with the Feb data yet?

iceman

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Re: Latest PIOMAS update (March)
« Reply #1372 on: March 04, 2017, 02:37:32 PM »
Attached my year-by-year anomaly graph showing the anomaly went just a little less negative in February.

A marginal improvement, but the persistence of the low anomaly is getting scary.  No room for a June cliff this year: it would be like diving headfirst into an empty pool.
     Any silver linings in the gloomy picture?
     1) The central basin is probably in somewhat better shape than overall.
     2) If the recent lull in Fram Strait export persists, it would give the weak ice north of Greenland and Svalbard a chance to recover a bit before the heavy melt hits.

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Re: Latest PIOMAS update (March)
« Reply #1373 on: March 04, 2017, 03:02:44 PM »
With low volume and normal FDD from 28Feb to max, then we should expect above average gain by maximum, right? Maximum above 21.3 k km3 does not seem impossible to me.

But I would expect the volume loss to be high due to low ice volume at max. There is also an upward trend in volume loss so a volume loss of just 17 k km3 would be surprising.

So seems pretty likely to beat 2012 minimum record with only room for about 0.5 k km3 more than that in a reasonable best case.

Arctic ice freeze/melt is countercyclical, but only mildly so. There have been 5 low maximum years so they might be the best comparison. These were 11, 12, 13, 14 and 16. In those years ice gained an average of 2.25 to maximum from day 60. Average melt was 18.13. Using those numbers for this year we get a maximum of 20.95 and a minimum of 2.82.

A record minimum is likely but complete collapse is very unlikely. A lot of people people seem to discount the fact that there are three big negative feedbacks always at play in the Arctic- lower insolation, lower temperature and lower ice transport to the melt zones.
2017 is enough of an outlier that some previously unseen phenomena might emerge. But going off of past history, a minimum of about 3.0 is a pretty good guess right now.

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Re: Latest PIOMAS update (March)
« Reply #1374 on: March 04, 2017, 03:49:18 PM »
Generally in agreement, two points to dispute:

  .... There have been 5 low maximum years so they might be the best comparison. These were 11, 12, 13, 14 and 16. In those years ice gained an average of 2.25 to maximum from day 60. Average melt was 18.13. Using those numbers for this year we get a maximum of 20.95 and a minimum of 2.82.
    Doesn't account for detrending: see graphs upthread.  Because the trend is steeper for losses than for gains, statistically we would expect a lower minimum than on basis of averaging the low-max years.

   ... there are three big negative feedbacks always at play in the Arctic- lower insolation, lower temperature and lower ice transport to the melt zones.
    Insolation is potentially a positive, not negative feedback (by latitude) around the solstice.  Granted this could be negated by a fourth feedback: increased cloud cover owing to higher atmospheric moisture, in turn from higher SSTs and more open water.

image credit: http://geography.name/insolation-over-the-globe/

Gray-Wolf

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Re: Latest PIOMAS update (March)
« Reply #1375 on: March 04, 2017, 04:07:31 PM »
I think the folk making fag packet calcs on final figures are not allowing for how much faster the end ice will go compared to mid season melt? Once ice gets to a certain size the melt switches from top/bottom giving the biggest losses to the contraction from the edges .

We will never know just how close we sailed to record losses last year but I reckon we came close and even at minimum had the ice occupied different locations we would have seen more ice lost?

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gerontocrat

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Re: Latest PIOMAS update (March)
« Reply #1376 on: March 04, 2017, 05:13:32 PM »
Hullo Iceman
Love the insolation graph. Worth a bookmark in anyone's computer.
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Re: Latest PIOMAS update (March)
« Reply #1377 on: March 04, 2017, 05:25:23 PM »
The revised PIOMAS SIV graph showing just how far out of whack things have become:


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Re: Latest PIOMAS update (March)
« Reply #1378 on: March 04, 2017, 07:14:45 PM »
Been reading / looking at PIOMAS feb analysis. GULP. Perhaps will vote again for a lower max volume prediction.
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jai mitchell

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Re: Latest PIOMAS update (March)
« Reply #1379 on: March 04, 2017, 07:56:36 PM »

(Though don't you mean 2011, and not 2010?)

Yes, I miscounted  :-[

well, shit. . .there goes the planet   :'( :'( :'(

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jai mitchell

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Re: Latest PIOMAS update (March)
« Reply #1380 on: March 04, 2017, 08:03:58 PM »
Hullo Iceman
Love the insolation graph. Worth a bookmark in anyone's computer.

of important note, to the graph of insolation, when I talk about albedo and the potential for blue water arctic on June 21 ( I estimate sometime around 2065) I make sure to tell people that, contrary to common understanding, during the Summer Solstice, the Arctic gets 25% MORE solar radiation than the tropics.  It should also be noted that the high amount of clouds in the tropics means that the total amount of absorbed shortwave (direct sunlight) radiation is likely much higher (possibly 50% more!)
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Re: Latest PIOMAS update (March)
« Reply #1381 on: March 04, 2017, 08:07:00 PM »
I think the folk making fag packet calcs on final figures are not allowing for how much faster the end ice will go compared to mid season melt?
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Re: Latest PIOMAS update (March)
« Reply #1382 on: March 04, 2017, 08:23:37 PM »
Here's a post from further up thread by a new ASIF member that I have just released (welcome johnd, you can post freely now):

As with extent, PIOMAS volume has had the lowest average monthly measurement the last  four consecutive months (NDJF), and it's going to be very difficult for March to *not* be in first as well.

Anyway, this is crazy:

Jim, could you just explain this spiral plot please for those less familiar with it? It's 12 sectors, presumably one per month, and the clockwise end of each sector would be the last day of the month? So am I correct in thinking that the current update only has data to the end of Jan 2017 and that you (or whoever generates it) have not had a chance to update it with the Feb data yet?
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Re: Latest PIOMAS update (March)
« Reply #1383 on: March 04, 2017, 09:19:49 PM »
I make sure to tell people that, contrary to common understanding, during the Summer Solstice, the Arctic gets 25% MORE solar radiation than the tropics.

That's really interesting. Is that as a whole, or per square meter, or what?

oren

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Re: Latest PIOMAS update (March)
« Reply #1384 on: March 04, 2017, 09:25:51 PM »
I make sure to tell people that, contrary to common understanding, during the Summer Solstice, the Arctic gets 25% MORE solar radiation than the tropics.

That's really interesting. Is that as a whole, or per square meter, or what?
Per square meter.

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Re: Latest PIOMAS update (March)
« Reply #1385 on: March 04, 2017, 10:21:58 PM »

    Doesn't account for detrending: see graphs upthread.  Because the trend is steeper for losses than for gains, statistically we would expect a lower minimum than on basis of averaging the low-max years.

Insolation is potentially a positive, not negative feedback (by latitude) around the solstice.  Granted this could be negated by a fourth feedback: increased cloud cover owing to higher atmospheric moisture, in turn from higher SSTs and more open water.


If you mean post #1358 then my response is that the slightly countercyclic nature of ice loss would outweigh the long term trend of increasing ice loss in summer.

Insolation is only a positive feedback for about 2.5 months at the peak. We still have 6.5 months to go until the expected minumum. Assuming that summing the areas between 60° and 90° is a reasonable approximation, then overall insolation feedback will be negative over that time period.

As you can see by Wipneus' volume anomaly graph volume has tended to increasingly reflect the insolation map. There is more extreme ice loss in mid-summer, but ice loss is lower in late summer and recovers more in the winter. However, this year clearly diverges from the trend of increased winter freeze. It's possible that whatever is causing this will continue into the melt season. I don't think you can count on this though since the melt/freeze seasons do not seem to be related, even having been slightly countercyclical over the last 10 years.

slow wing

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Re: Latest PIOMAS update (March)
« Reply #1386 on: March 04, 2017, 10:46:35 PM »
I'm still uncertain on how much insolation the Arctic actually gets.

Is the plot showing insolation on a horizontal surface? Or on a tracking surface always perpendicular to the sun? (I presume the former.)


More importantly, does it include a model or measurement of the effects of the atmosphere, including the variable moisture content and cloud cover? If it's insolation at the top of the atmosphere then that's much larger than what reaches the ground. That is particularly true in the Arctic, given the typically low solar elevations from the horizon.

  The Arctic was cloudier than usual last summer, so the insolation reaching the ground would also have been less than usual. Will this summer be similar?


So the question of how much insolation reaches the Arctic is not simple and is not fully addressed by a single graph.

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Re: Latest PIOMAS update (March)
« Reply #1387 on: March 04, 2017, 11:22:57 PM »
This is a sample from CERES https://ceres-tool.larc.nasa.gov/ord-tool/srbavg
Note that the colour scale is not the same for the different products.
What is shown are monthly averages in Watts hitting a horizontal square meter.
Greenland because of altitude and clear atmosphere does get more insolation than the Sahara. Otherwise the shallow sun angle means longer path through the atmosphere which reduces what reaches the ground even on clear days.
The effect of albedo is seen in the third plot which shows net (incoming minus reflected) shortwave. Once outgoing Longwave is taken into account Greenland is gaining very little even in June.

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Re: Latest PIOMAS update (March)
« Reply #1388 on: March 04, 2017, 11:34:35 PM »
Here's a post from further up thread by a new ASIF member that I have just released (welcome johnd, you can post freely now):

Jim, could you just explain this spiral plot please for those less familiar with it? It's 12 sectors, presumably one per month, and the clockwise end of each sector would be the last day of the month? So am I correct in thinking that the current update only has data to the end of Jan 2017 and that you (or whoever generates it) have not had a chance to update it with the Feb data yet?

Hey, John. To second what Neven said, welcome to the forum.

Can I assume you're referring to the top image below? When I uploaded that image onto the server yesterday afternoon (EST), it was definitely the correct version with all January and February data reflected. If you were seeing an image with only January, you may have been seeing a cached copy. Google currently hosts the images, so it's possible they weren't keeping up for a short period



If by chance you were referring to the interactive 3D "death spiral" graph below, partial weeks won't show until the following month, so a short month like February will only move the circumannual arc by a slight bit. It should be much more illustrative next month.


slow wing

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Re: Latest PIOMAS update (March)
« Reply #1389 on: March 05, 2017, 01:10:42 AM »
Terrific information, thanks Andreas! Your reply, #1387 above, beautifully addressed my question on how much insolation the Arctic actually receives.

What a great forum this is!

jdallen

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Re: Latest PIOMAS update (March)
« Reply #1390 on: March 05, 2017, 01:36:56 AM »
I'm still uncertain on how much insolation the Arctic actually gets.

Is the plot showing insolation on a horizontal surface? Or on a tracking surface always perpendicular to the sun? (I presume the former.)


More importantly, does it include a model or measurement of the effects of the atmosphere, including the variable moisture content and cloud cover? If it's insolation at the top of the atmosphere then that's much larger than what reaches the ground. That is particularly true in the Arctic, given the typically low solar elevations from the horizon.

  The Arctic was cloudier than usual last summer, so the insolation reaching the ground would also have been less than usual. Will this summer be similar?


So the question of how much insolation reaches the Arctic is not simple and is not fully addressed by a single graph.
It is flat surface, and it is maximum potential unfiltered by other factors that shift albedo and absorbtion.

It is useful because it provides us with a "top end".  If we can reasonably establish albedo, we can extrapolate from that how much energy is reaching the ice, though if we're dealing with large quantities of h20 in the atmosphere, we'd need to factor in down-welling IR as well.
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Andreas T

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Re: Latest PIOMAS update (March)
« Reply #1391 on: March 05, 2017, 02:29:30 AM »
you are welcome, slow wing. Looking at the area around Greenland we can see the effect of albedo on heat input from radiation (I have selected  balance of shortwave and IR this time). It clearly is a major factor as areas of open water or ice free land in Baffin bay and north east Greenland show. So if, and when, open water appears earlier in the melt season this should increase available energy for melt, i.e. be a positive feedback. Whether an increase in clouds is strong enough to change that is the big question. In such a cold place clouds, which radiate IR down to the surface and transmit some diffuse sunlight are not as much of a cooling factor as we are used to in lower latitudes.

P-maker

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Re: Latest PIOMAS update (March)
« Reply #1392 on: March 05, 2017, 09:39:21 AM »
Andreas T,

Thank you for providing these very illustrative diagrams. They led med to think about an old illustration, I came across many years ago.

Basically, it was a “raw” average of observed cloud cover from exactly the area shown in your diagram, It was based on monthly time series from around 80 climatological surface stations over the period 1890 through 2000.

In summary, it was evident that cloud cover in the Nordic Seas region had historically been on average between 60 % (Summer) and 75 % (Winter). It was also clear that the general warming, which took place in this area between around 1920 and the 1930ies, added appr. 5 % points to the average cloud cover back then.

Assuming this most recent warming period has also added another 5-10 % to the cloud cover (actually it is sky cover seen from the ground), then it is highly likely, that infrared radiation reflected back to the ground from the bottom of the clouds is a stronger positive feedback, which more than compensates the increase in shortwave radiation being reflected back to space due to the increase in cloud cover.

So, in some ways, we might assume that loss of sea ice (with high albedo) leads to an increase in clouds locally (with similar high albedo as seen from the sky), so the main difference will be the increase in longwave back radiation (as seen from the surface).

In my view, the warming, the loss of sea ice and the increase in cloud cover all go together, so trying to separate things and let one be the driver of others could be a futile exercise.

johnd

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Re: Latest PIOMAS update (March)
« Reply #1393 on: March 05, 2017, 10:15:12 AM »
Can I assume you're referring to the top image below?

Yes, correct it was the top chart. And yes it was maybe some sort of caching issue, maybe Google servers take a while to synchronise between different data centres because I'm pretty sure that I did refresh locally and more than once. Or maybe there's some other explanation (embedded images in posts also need a while to update?)? But, thanks, either way I can see the March update correctly today.

Nick_Naylor

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Re: Latest PIOMAS update (March)
« Reply #1394 on: March 05, 2017, 03:38:44 PM »
Another view, showing 2016-17 against the decade-by-decade decline.

Blizzard92

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Re: Latest PIOMAS update (March)
« Reply #1395 on: March 06, 2017, 10:40:29 PM »
I've updated all of my sea ice thickness/volume plots for February (from PIOMAS) at http://sites.uci.edu/zlabe/arctic-sea-ice-volumethickness/
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Pragma

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Re: Latest PIOMAS update (March)
« Reply #1396 on: March 07, 2017, 12:22:33 AM »
It's too early for me to do this, but maybe everyone will forget by September: I will go out on a very short limb and (probably foolishly) predict a PIOMAS volume minimum between 1.8K and 2.2K.

I believe in "state change", and I believe that 2017 is the transition year. So I predict a PIOMAS volume minimum between 0.8K and 1.2K.

I agree that we have experienced a state change, but IMHO it occurred last year or 2015, but the step is being smeared by the high specific heat of water. I also agree that this year things are likely to fall off a cliff. Had last year been only slightly different, it could have happened then.

As Gray-Wolf said, "When it finally goes it will go fast". I will add to that, that when we hit zero, self reinforcing effects will make recovery unlikely.

I am tempted to jump in with a prediction number but keep in mind that the remaining volume is now approaching the natural variability, or noise of the system, so while at least we have one more year of a non-zero minimum, I think predicting final minimums (or when we hit zero each year) is almost a lottery.

But, like a lottery, it's still fun to play.  :) What the heck, 1700 km^3 +/- 250.

RikW

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Re: Latest PIOMAS update (March)
« Reply #1397 on: March 07, 2017, 10:04:16 AM »
I wouldn't be surprised if we go almost or totally ice-free this year. The more sea ice area, the more heat can be reflected. So with less sea ice, there will be less reflection of radiation. So there is less energy needed to melt everything, because there is less sea ice, and there will probably more energy available because of less reflection and global warming.

Makes it hard to make an educated guess, so when there will be a voting topic about this I'll vote Ice-free.
If it's ice-free I win because i guessed correctly
If it's not ice-free I win, because we have more years enjoying arctic sea ice

So voting zero is a sort of win-win situation ;)

gerontocrat

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Re: Latest PIOMAS update (March)
« Reply #1398 on: March 07, 2017, 10:54:18 AM »
This is not the right thread to place this BUT perhaps the Trump Presidency's proposal to cut the NOAA budget by 26 percent from October 1st should be posted everywhere.

The war on climate science has really begun ?
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meddoc

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Re: Latest PIOMAS update (March)
« Reply #1399 on: March 07, 2017, 12:18:01 PM »
Yeah and Trump is not allowed to make Peace with Russia- or else, is called a Russian spy.
By the NSA- Puppet Obummer- whose great Climate Plan is initiating a Nuclear Winter by all means possible provoking Russia.