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Messages - gerontocrat

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101
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: July 01, 2019, 03:09:33 PM »
Instead of making stuff up about winds and waves, you all might consider reading articles in the literature. You might start here to learn about what's happening in the Bering strait.
https://www.sciencedirect.com/science/article/pii/S0079661117302215

As to my earlier post in this thread, Frivolous points out elsewhere that the summer water layer may not interact with the surface layers. However, Ekman pumping and eddies in the Beaufort sea may bring some of that stored heat to the surface. Ekman pumping is important along the continental shelf margin of the Beaufort sea when high pressure is sustained and easterly winds blow for days. I'm not sure what's causing the apparent mixing now that buoy 110 is reporting.
I read it, and from it came away with:-
Quote
A seasonal warming trend in the strait proper in May and June (∼0.04 °C/yr) is reflected in a trend to earlier arrival (0.9 ± 0.8 days/yr) of waters warmer than 0 °C. Contrastingly, no significant trend is found in the time of cooling of the strait. 
If I read that right, I am surprised - the hotter sea not delaying the freeze date?

and:-
Quote
By separating the flow into portions driven by (a) the local wind and (b) a far-field (Pacific-Arctic “pressure-head”) forcing, we find the increase in the Bering Strait throughflow is primarily due to a strong increase in the far-field forcing, not changes in the wind.

so googling I found:- http://psc.apl.washington.edu/HLD/Bstrait/Woodgate_BeringStrait_ASOF_Apr2018Final.pdf

Which with a vast collection of graphs, maps etc tells you just about everything, and includes the message repeated in the sciencedirect.com article -

Quote
Finally we conclude that year-round in situ mooring are still the only currently viable way of obtaining accurate quantifications of the properties of the Pacific input to the Arctic.

102
4.00 million km2. I have said it so it will be so.

103
Arctic sea ice / Re: Global sea ice area and extent data
« on: July 01, 2019, 12:11:05 PM »
JAXA Global Sea Ice Extent as at 30 June 2019 :  22,754,070 km2

This week was a mixture of very high extent gain and then a run of extent losses.

Global extent in 2nd place, 90 k above 2017, and 993 k below 2018.

- extent loss on this day 18k, 21k different from the the average gain of 3 k on this day,
- extent gain from minimum to date is 6.50 million km2, 1.01 million km2 (13.4%) less than the average gain of 7.51 milllion km2 by this day,
-on average 83.3% of extent gain done and 127 days to maximum in early November.
 
But before the maximum, there is firstly a false maximum (in July). Indeed the average for the 2010's has this false max in the last week in June. For the next 2 and a bit months extent should fall until the false minimum (in early September),  before rising to the (usually) true maximum around the 4th of November.

The Perils of Projections
The last 10 years average remaining extent gain would give a maximum of 24.26 million km2,  0.63 million km2 more than the record low maximum in 2016 and 2nd lowest in the satellite record.

Being a combination of two separate pieces of data volatility is very high. The last table shows how remaining freeze varied from the average from  plus 80% to minus 99%.

104
Antarctica / Re: Sea Ice Extent around Antarctica
« on: July 01, 2019, 11:40:12 AM »
JAXA ANTARCTIC Sea Ice Extent :  13,717,589 km2(June 30, 2019)

The last week started with very high extent gains and finished with - very low extent gains. 2019 is now 2nd lowest in the satellite record, 85 k above 2017 and 668 k below 2018.

- Extent gain on this day 40 k, 46 k less than the average gain of 86 k on this day.
- Extent gain from minimum is 11.293 million km2, 0.731 million km2 (6.1%) less than the average of 12.024 million km2 by this day,
- 75.5% of average extent gain done, with 78 days to the average date of maximum (16 Sept).

The Perils of Projections
Remaining average freeze of the last 10 years gives a max of 17.65 million km2, 0.41 million km2 less than 2017 (the record low maximum year).
______________________________________________________________________

105
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 30, 2019, 03:57:43 PM »
It's Sunday. Thought avoidance day.

106
Arctic sea ice / Re: The 2019 melting season
« on: June 30, 2019, 01:41:40 PM »
Surge of water into the Chukchi?
The classic geographical features required for a large surge of ocean water (as opposed to a storm surge) is a wide channel, gradually narrowing and gradually shallowing. The Bristol channel / Severn Estuary in England is a classic example. There the surge is associated with Spring (US = King ?) tides.

The bathymetry of the Bering Sea is not a good shape for such a surge.

A long period of a good consistent wind over a long uninterrupted fetch will produce a big swell, hence the tens of metres swells in the Southern Ocean. In the North Pacific the steady wind is there, the long fetch is there. But it is interrupted by the archipelago of the Aleutian Islands. (And a swell does not increase sea level - a 6 foot swell is +/- 3 feet from mean sea level ). So all I can see is some warm surface water being persistently pushed through the Strait to some effect.

The only way I can see a really large influx of water through the Bering Strait into the Chukchi is very low pressure in the Bering Sea lifting sea level, plus very high pressure in the Chukchi depressing sea level. Water flows downhill. That does not exist nor does it look like doing so.

But a wall of water? I don't think so. The physical geography defeats it.

107
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: June 30, 2019, 11:49:38 AM »
http://polarportal.dk/en/greenland/surface-conditions/ as at 29 June 2019

Almost a word for word repeat of yesterday's post because this event just will not stop.

Melt remains strong and even stronger yet again, the maximum again for the year. Again concentrated in the West and the South. I am sure the persistence of this strong melt is unusual, as normally we just see strong short-term spikes.

Precipitation, mainly in the South East, was not strong, and mass loss was above average.

Outlook - a tale of 2 halves, West and East.

GFS Precipitation outlook for the next 7 days now looking  like very dry to drought in the West coast and centre, some precipitation all the way down the East coast. Much is coming all the way from a warm/hot western Siberia passing over the Atlantic edge of the Arctic sea ice. A bit of rain may come from the south to affect the southern tip of Greenland. GFS says at least on the fringes (i.e. at low altitude) some precipitation is likely to fall as rain.

Melt. Temperatures above freezing around most of the coast in the next week, with considerable warmth arriving into the far North. Perhaps melt above average to very much above average. The SST anomalies in Baffin Bay can only increase.

SMB mass change is a matter of which will prevail, precipitation and melt. But it still looks likely the SMB graph will show the 2019 line continuing to cross the 2012 red line in a day or two.
And what is the prognosis for calving given all this melt and runoff ? Not a lot of news about icebergs in Baffin Bay and iceberg alley to be found.

It becomes clear that precipitation, or the lack of it, may determine the overall SMB loss during the melting season at least as much as melt. My speculation is that in 2012 lack of precipitation was as or more important than melt in the unprecedented SMB loss that year.
_____________________________________________________
Note from DMI

When comparing melt with the surface mass balance under ”Daily change”, note that melting can occur without surface mass loss since the meltwater can refreeze in the underlying snow. Likewise, surface mass loss can occur without melting due to sublimation.

The map illustrates how the surface of the Greenland Ice Sheet gains and loses mass on a daily basis. This is known as the surface mass balance. It does not include the mass that is lost when glaciers calve off icebergs and melt as they come into contact with warm seawater.


Note from me (to any denier creeps out there):
From 2002 to 2017 Greenland lost over 3 thousand billion tons of mass, an average of nearly 300 billion tons per annum. This is about the same as the average annual mass loss of ice from the entire Arctic Seas.
https://climate.nasa.gov/vital-signs/ice-sheets/

This is simply because mass loss from glaciers calving exceeds mass gain on the surface from snowfall.

108
Is not the Arctic warming at twice the rate of the world average?
If so, and the ratio is maintained, for the Arctic +4 = +8.

I think that means an ice-free Arctic summer.
I think that means an awful lot of Greenland Ice Sheet melting.
I assume the Antarctic gets somewhat warmer. I guess that means WAIS collapse.

I think that means AbruptSLR happening and unstoppable.
I think that means many hundreds of millions of people having to move. Where to?

Other major impacts
- too much water (not one-off floods, permanent rainfall increase) in some places
- too little water (not one-off drought, permanent rainfall decrease) in other places
- too much heat so large areas become Death Valley

A lot more of the planet becomes unsuitable for human habitation e.g. Middle East, Phoenix, Las Vegas, large parts of the Mississippi Missouri river basin.

Another few hundred million people have to leave. Where to?

NOT HERE. KEEP OUT!!
Europe bans immigration. Navies shoot on sight migrant ships.
Trump's successors build an electrified wall - border guards shoot on sight (learning from example of the Berlin Wall)

After several really difficult generations what comes out the other end ?
- A high-tech AI new human civilisation, or
- A few humans surviving quite well with pre-industrial technology, or
- Fewer humans than today with enough technology and the determination to screw up all over again. You can't change the nature of the beast?

I think if your game assumes that +4 degrees is going to happen it can't have a happy ending.
I've made myself a bit gloomy.

109
Arctic sea ice / Re: The 2019 melting season
« on: June 29, 2019, 06:26:47 PM »
My last speculation is - all other things being equal - that minimum will be later than average this year (October 1 - only half-joking).
Daring!  The decadal trend 1979-2010 (Charctix interactive extent below) was towards a later minimum, but that reversed somewhat in the last decade (2011-2018).   This was counterintuitive to me.  But maybe if ice melts so far back that there is open ocean close to the pole, then that far north open ocean refreezes quickly as winter approaches??
That is true - but sumfinks gotta give, sometime.

Meanwhile, how about a grenade?

DIspersion vs Concentration
A lot of talk about how mobile broken up ice can make extent data greater than reality (15% rule, NSIDC 625 km2 pixels) - especially this year. The convention is to look at concentration, i.e. area divided by extent to see what is going on.

I thought, as we are talking about dispersion, let's try dispersion instead, i.e. extent divided by area. This also has the advantage of a larger number divided by a smaller number making the differences more marked. I attach the first graph that looks at all Arctic Seas. A ratio of 100% would be solid ice, a ratio of 2 would mean extent dispersed over twice the actual ice there as measured by area.

It is obvious that as the years go by dispersion increases markedly. It is also obvious that something weird happened in 2012.

2012 and the Great Arctic Cyclone (GAC)- & Arithmetic

Convention has it that the GAC smashed up the ice and sent it all over the place. Did it?

By end July 2012 Arctic Sea Ice was well on its way to a record low. Area was decreasing even faster than extent and thus the dispersion ratio increased strongly to record levels in early August not seen before or since. Thin fragmented dispersed ice everywhere.

Then from August 2nd to August 14 was the GAC.  From August 9th to end August dispersion crashed from nearly 170% to the 2010's average of 155%. This means area loss was below extent loss. The GAC did not disperse the ice, it shoved it together. Concentration (compaction) increased.
______________________________________________________________________
Contrast this with 2016. Dispersion increased to above 2012 levels until the sea ice minimum.
What will 2019 do? On this melting season thread most say - melt.
___________________________________________

ps: Up above someone posted the dread DMI Sea Ice Thickness graph. I thought that one had a health warning (even more so for their volume graph?)?


110
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: June 29, 2019, 04:02:56 PM »
From this post:

June 1-28

Trailing 5-day median

https://seaice.uni-bremen.de/databrowser/

Here you can see the abrupt stopping of the current and how the floes accumulated in Kane, Sterks.
You can also see a big lump of fast ice attached to the Greenland shore detaching, breaking up and drifting into the basin. Dispersion in action.

Note: In this case the amount of ice is the same (maybe even less as melting did occur) but got spread out over a much bigger area. This has happened quite a lot over quite a lot of places this season, distorting the data, especially NSIDC extent data due to the 15% rule and large 625 km2 pixels confusing the sensors.

But very soon - history.

111
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: June 29, 2019, 03:48:27 PM »
gerontocrat...are the gray shaded areas 1 SD or 2 SD from the mean?

Neither.

Don't ask me why but  DMI  does this on the SMB graph and the melting graph..

"The light grey band shows differences from year to year. For any calendar day, the band shows the range over the 30 years (in the period 1981-2010), however with the lowest and highest values for each day omitted."

So the amazing stuff e.g. 2012 when nearly all of Greenland was melting for a couple of days - is not there.

112
Arctic sea ice / Re: The 2019 melting season
« on: June 29, 2019, 03:28:07 PM »
My first speculation is that there is a correlation between the speed and timing of area loss in the various regional seas, the Albedo Warming Potential in the various regional seas, and the geographical location and intensity of SST Arctic anomalies.

I suggest cause and effect are in that order. i.e. all other things being equal, early melting means longer time available for a sea to heat up. Obvious examples are the very high temperatures in the Bering and Chukchi now spreading into the Beaufort, and the blob of high SSTs in the Laptev bite.

Now I don't know how much direct effect these warm seas influence the rate of warming of the neighbouring ice. I do remember a poster (was it Oren?) saying - the weather is the trigger, but the bullet is ocean warmth. And the heat in the oceans has been growing remorselessly for many, many years.

But my 2nd speculation that belongs to me is that these high SSTs must inhibit re-freezing (all other things being equal) and therefore tend to reduce ice thickness at the following maximum. I give as evidence that the ice volume maximum is reducing at an average rate of 280 km3 per year, while the the minimum is reducing at a not much higher rate of 320 km3 per annum. This is in contrast with winter maximum extent and area which is falling at a pitifully low rate.

Note especially that Tealight's AWP graph shows 2016 AWP anomaly as the highest and earliest, and that April 2017 volume maximum dipped well below the trend line.

So my 3rd speculation that belongs to me is that if the 2019 AWP anomaly continues to exceed or match that of 2016, re-freezing will be delayed, and the April 2020 Ice Volume maximum will be below the trend line. This does not require 2019 area and/or extent to be a new record low - matching 2016 would likely do it.

My last speculation is - all other things being equal - that minimum will be later than average this year (October 1 - only half-joking).

https://cryospherecomputing.tk/NRTawp
http://psc.apl.uw.edu/wordpress/wp-content/uploads/schweiger/ice_volume/BPIOMASIceVolumeAprSepCurrent.png
http://psc.apl.uw.edu/research/projects/arctic-sea-ice-volume-anomaly/

113
Arctic sea ice / Re: Global sea ice area and extent data
« on: June 29, 2019, 09:01:35 AM »
VOLATILITY

What a difference 2 days makes.

   Arctic sea ice loss was low,
   Antarctic sea ice gain was high.
Global extent quickly rising.

2 days later,
   Arctic sea ice loss is high,
  Antarctic sea ice gain is low.
Global extent slumps.

Will the change persist? On Monday an overall look at June.

114
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 29, 2019, 08:18:57 AM »
JAXA ARCTIC EXTENT :-  9,190,076 km2(June 28, 2019)

First double century break since March 29-30.

- Extent is 4th lowest in the satellite record.
- Extent loss on this day 135 k, 36 k more than the average loss on this day of 99 k.
- Extent loss from maximum 5,081 k, 212 k (4.4%) greater than the average of 4,869 k loss from maximum by this day,
- On average 49.3% of the melting season done, with 77 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt would give a minimum of 4.18 million km2, 4th lowest in the satellite record, and 1.00 million km2 above the 2012 low of 3.18 million km2.
Looking at the last 5 years average remaining melt gives a result of 4.25 million km2, also 4th lowest, and 1.07 million km2 above 2012.

Other Stuff

A messy picture, GFS showing  temperature anomalies in a narrow range of +0.7 to +1.5 degrees celsius disguising movement of high and low temepratures over the land around the Arctic,  in contrast again with a mostly modest +ve anomaly over most of the Arctic Ocean for most of the time.

The CAA, Baffin Bay and Hudson Bay are mostly warm, with periods of warmth and cold in Western Canada and Alaska. High +ve anomalies most of the time in Central Siberia and Western Siberia contrasting with long periods of cooler weather over land bordering the ESS;

The GFS 5 day wind outlook from GFS shows persistent strong southerly winds from The North Pacific entering the Arctic Ocean via the Bering Strait. This outlook also shows persistent strong winds from the Kara across the Arctic into the North Atlantic, that may persist or even strnegthen in the following 5 days.

A complicated picture inadequately described above.

We are now entering the period of maximum daily extent loss that lasts until mid or late July and then very gradually declines. Extent loss on this day again much above average.
_____________________________________________________________________
The volume data for June should be available by late next week. It will be interesting to see what has happened to volume and from that, perhaps more importantly, thickness during this month.

NSIDC area data is, for once, mirroring extent data. Interesting again will be where major losses are happening, and where they are not.

115
Arctic sea ice / Re: The 2019 melting season
« on: June 28, 2019, 06:43:54 PM »
How is that insolation anomaly created.

Are we using something to determine if there was clear skies or not
Tealight did it. Over simplified explanation below.
Uses the area data and applies the standard insolation parameters to each bit of data with albedo dependent on open water or ice.

It is Albedo Warming POTENTIAL. -  does not take into account cloudiness. So actuality by definition must be less. There must be clouds somewhere. If you have a few billion bucks lying around doing nothing I guess somwhere somone might sort the cloudiness thing out. But looks damn complicated given the varying natire of clouds.

But it is telling us that the direction of travel this year is DOWN even given average weather.

116
Arctic sea ice / Re: The 2019 melting season
« on: June 28, 2019, 11:33:25 AM »
I agree that the ice thickness in mid July determines who will survive in Sep.

Are we going to be shot if our predictions are wrong?  :o
No. Worse.

You will be trapped in the circular meta-discussion gyre with no parole.

117
Arctic sea ice / Re: The 2019 melting season
« on: June 28, 2019, 09:20:56 AM »
I guess this is actually part of the ESS rather than the Laptev.
I still have to check the arbitrary boundaries of these seas every so often using NSIDC's MASIE@ https://nsidc.org/data/masie.

Click on browse regions and choose your sea. Example attached.

118
Arctic sea ice / Re: The 2019 melting season
« on: June 27, 2019, 05:35:44 PM »
the source for the Slater maps .. I would like to be able to follow the graph .
https://cires1.colorado.edu/~aslater/SEAICE/

lots of other stuff there

119
Arctic sea ice / Re: Global sea ice area and extent data
« on: June 27, 2019, 11:17:13 AM »
JAXA Global Sea Ice Extent as at 26 June 2019 :    22,872,881 km2

On this day Arctic extent loss was below average, and Antarctic extent gain was double  the average. So extent has slumped to 2nd lowest especially because 2017 extent reduced a lot on this day.

Global extent is now 163 k above 2017, and 740 k below 2018.

- extent gain on this day 123k, 108 k more than the the average gain of 15 k on this day,
- extent gain from minimum to date is 6.62 million km2, 0.91 million km2 (12.1%) less than the average gain of 7.53 milllion km2 by this day,
-on average 83.5% of extent gain done and 131 days to maximum, but before that there is a false maximum (in July) and a false minimum (in September) before the (usually) true maximum around the 4th of November.

The Perils of Projections
The last 10 years average remaining extent gain would give a maximum of 24.36 million km2,  0.73 million km2 more than the record low maximum in 2016 and 2nd lowest in the satellite record.

Being a combination of two separate pieces of data volatility is often very high. Confidence in any projection is even lower than normal. However, the JAXA extent data so far does not point to a change to the usual pattern of a false maximum in July, a false min in Aug/Sep and a final max in early November.

120
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: June 27, 2019, 09:53:46 AM »
http://polarportal.dk/en/greenland/surface-conditions/ as at 26 June 2019

Melt remains strong and even stronger, very much above average, near the maximum for the year. The persistence of this strong melt is unusual? GIF attached shows history since June 10 (wobbles a bit - not a clue why). Click to start, runs 5 times and then stops.

Precipitation was not enough to reverse daily SMB mass loss to zero, but mass loss less than average.

GFS has changed the [/i]Precipitation outlook for the next 7 days. Now looking  like very dr y in the NW, much wetter in the SE (a more normal pattern). At least on the fringes (i.e. at low altitude) some precipitation is likely to fall as rain.

Melt. Temperatures above freezing around most of the coast in the next week, with considerable warmth arriving into the far North by Friday. Perhaps melt above average to very much above average.

SMB mass loss to continue to reverse into mass gain or reduced mass loss? It is now looking likely the SMB graph will show the 2019 line crossing the 2012 red line in a day or two.

It becomes clear that precipitation, or the lack of it may determine the overall SMB loss during the melting season at least as much as melt. My speculation is that in 2012 lack of precipitation was as or more important than melt in the unprecedented SMB loss that year.
_____________________________________________________
Note from DMI

When comparing melt with the surface mass balance under ”Daily change”, note that melting can occur without surface mass loss since the meltwater can refreeze in the underlying snow. Likewise, surface mass loss can occur without melting due to sublimation.

121
Arctic sea ice / Re: The 2019 melting season
« on: June 26, 2019, 10:22:06 PM »
The strong East Greenland current flows North to South.

A lump of ice about 40 x 20 miles has come away off the ice attached to NE Greenland. It is going - North.
A bit farther south at Dove, there is a load of ice flowing - East.

Image re NE Greenland attached.

122
Policy and solutions / Re: Nuclear Power
« on: June 26, 2019, 08:54:16 PM »
And since there is no need.......
And that is the final and conclusive point.

There is no need for nuclear power. So why do it?

123
Arctic sea ice / Re: The 2019 melting season
« on: June 26, 2019, 07:54:11 PM »

Called it!  8)

It's fixed.  I set the res above 701 to prevent autoload and also made a super lossy optimization (they only got down to about 10 MB though).

I will gif more carefully in the future.
Thanks, my clapped out laptop and lousy rural internet connection had a bad case of heartburn

124
The forum / Re: Suggestions
« on: June 26, 2019, 07:41:14 PM »
Hi Neven,

EDIT burnrate has fixed it. Please ignore the following message.

A new guy, burnrate, has just posted a couple of large gifs THAT WON'T STOP.
Can you kill them?

https://forum.arctic-sea-ice.net/index.php/topic,2591.msg208493.html#msg208493

Help !!

Gero

125
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 26, 2019, 01:33:28 PM »
Jaxa AMSR2 Arctic sea ice volume calculated by Wipneus
I think you have just chucked a grenade into the arena.
And if PIOMAS come up with something similar next week.......

126
Arctic sea ice / Re: Global sea ice area and extent data
« on: June 26, 2019, 01:18:40 PM »
JAXA Global Sea Ice Extent as at 25 June 2019 :   22,749,877 km2

In the last few days Arctic extent loss was mostly below average, and while Antarctic extent gain was much above the average. However, extent went back to lowest simply because 2017 extent ticked up, but only just, now for 75 days this year.

Global extent is now 13 k below 2017, and 801 k below 2018.

- extent gain on this day 48 k, 32 k more than the the average gain of 16 k on this day,
- extent gain from minimum to date is 6.50 million km2, 1.02 million km2 (13.5%) less than the average gain of 7.52 milllion km2 by this day,
-on average 83.3% of extent gain done and 136 days to maximum, but before that there is a false maximum (in July) and a false minimum (in September) before the (usually) true maximum around the 4th of November.

The Perils of Projections
The last 10 years average remaining extent gain would give a maximum of 24.26 million km2,  0.62 million km2 more than the record low maximum in 2016 and 2nd lowest in the satellite record.

Being a combination of two separate pieces of data volatility is often very high. Confidence in any projection is even lower than normal. However, the JAXA extent data so far does not point to a change to the usual pattern of a false maximum in July, a false min in Aug/Sep and a final max in early November.

127
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 26, 2019, 08:44:01 AM »
JAXA ARCTIC EXTENT :-  9,504,475 km2(June 25, 2019)

- Extent is 6th lowest in the satellite record.
- Extent loss on this day 93 k, 29 k MORE than the average loss on this day of 69 k.
- Extent loss from maximum 4,767 k, 159 k (3.04%) greater than the average of 4,608 k loss from maximum by this day,
- On average 46.6% of the melting season done, with 80 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt would give a minimum of 4.23 million km2, 4th lowest in the satellite record, and 1.05 million km2 above the 2012 low of 3.18 million km2.
Looking at the last 5 years average remaining melt gives a result of 4.32 million km2, 6th lowest, and 1.14 million km2 above 2012.

Other Stuff

Over the next 7 days GFS showing  temperature anomalies at +0.8 to +1.7 degrees celsius. Until the weekend the images suggest high +ve anomalies in central and eastern Siberia, with contrasting and sometimes strong -ve anomalies for most of the time on land and coastal sea by and in the Beaufort/CAA and Western Siberia, and in contrast again mostly +ve anomaly over most of the Arctic Ocean.

Over the weekend the picture changes somewhat. By Monday the CAA gets warmer, NW Canada and Alaska get a lot colder, and on the Russian side warmth moves west into areas bordering the Laptev and Kara, while the ESS area switches from strong warmth to a cold snap. However, over the Arctic Ocean itself there is a modest +ve  temp anomaly. Overall the Arctic temp anomaly stays well below 1 degree celsius.

A complicated picture inadequately described above.

We are now entering the period of maximum daily extent loss that lasts until mid or late July and then very gradually declines. For a change, extent loss on this day well above average.

_____________________________________________________________________
The volume data for June should be available by late next week. It will be interesting to see what has happened to volume and perhaps more importantly, thickness during this month.

128
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: June 25, 2019, 09:56:25 PM »
Yeah, kind of a flop my theory there.  :-X
You have company? SHE a bit of a flop too?

129
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 25, 2019, 08:14:49 PM »
NSIDC  Data as at 24 June 2019 (5 day trailing average)

And to finish - the Okhotsk, the Hudson & my favourite, the St. Lawrence

The Okhotsk maxed above the 2010's average, melted out very fast and approached zero well before the 2010's average.

The Hudson is melting out at the 2000's average but a week or so ahead of 2018. It will be done as near as makes no difference in 5 weeks or even less.

The St. Lawrence. The universal opinion is that there is zero ice here. Spurious, artefacts***. Huh, you're all a bunch of unbelievers. The graph proves it!!!
_________________________________________________________
*** artefact - something observed in a scientific investigation or experiment that is not naturally present but occurs as a result of the preparative or investigative procedure.
___________________________________________________________________

After all that,
NSIDC September average will be 4.25 million km2.
JAXA daily extent minimum will be 4.00 million km2, on October 1st to cause maximum confusion

I have decided this using royal privilege.

130
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 25, 2019, 07:50:03 PM »
NSIDC  Data as at 24 June 2019 (5 day trailing average)

The CAA, the Beaufort Sea & the 3.2 million KM2 Central Arctic Sea/Basin (aka The Big Beast) are worth considering as a group.

The CAA is losing area well above the 2010's average rate. And note how it looks like it just might avoid the 3 week hiatus in area loss that seems to be usual at this time. A bit of a mystery as the CAA has been a bit cool recently.

The Beaufort Sea quickly lost area to become lowest by the beginning of June. Then on the 10th June area loss stalled and then area started to increase to the extent that on this day area is 5th lowest in the satellite record. Much discussion on the melting season thread about changes in drift and wind affecting the Beaufort gyre.  The melting out of the Beaufort is delayed. (Caveat - volume/thickness)

The Central Arctic Basin area loss to date is well below the 2010's average. But the season has barely started so is of little significance. Of interest is that the lowest minimum was in 2016, not 2012. Perhaps this reflects loss of multi-year ice between 2012 and 2016. There is little doubt that this loss of multi-year ice has continued.

If the Arctic is reasonably warm from now on perhaps the volume and thickness of the Central Arctic Sea is critical ?

131
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 25, 2019, 03:29:24 PM »
NSIDC Greenland Sea Data as at 24 June 2019 (5 day trailing average)

Papers written some years ago said that 90% of the ice leaving the Arctic Ocean was transported by the East Greenland current. So at this time melting is at war with fresh ice arriving from the Fram. At the moment, melting is winning. The NSIDC map shows this very well indeed. (look from South to North)

132
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 25, 2019, 02:34:16 PM »
NSIDC Data as at 24 June 2019 (5 day trailing average)

Graphs attached look at Tealight's "High Arctic" - the 7 seas - Kara, Laptev, ESS, Chukchi, Beaufort, CAA, and the 3.2. million km2 of the Central Arctic Sea/Basin.

Area shows 2019 maintaining its position between 2012 and 2016.
Extent shows 2019 in pole position.

The result is concentration (area divided by extent) tends to stay up, against the normal trend for concentration to go down as the season progresses. The last 2 days of very high area loss have reversed this a tad.

Tealight's High Arctic Cumulative AWP anomaly at the moment also shows steady progress to a 2nd highest value 'twixt 2012 and 2016.
_____________________________________________________________________
Overall the NSIDC data suggests progress towards a lowish minimum in September. My prediction that belongs to me of a 4 million km2 JAXA daily minimum , (not a km2 more, not a km2 less,) is still intact (so far).

PIOMAS June data could kick the whole thing into touch.

133
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 25, 2019, 02:06:20 PM »
NSIDC Total Area as at 24 June 2019 (5 day trailing average) 7,698,353  km2
                        
Total Area         
 7,698,353    km2      
-265,666    km2   <   2010's average.
-312,713    k   <   2018
-890,044    k   <   2000's average.
         
Total Area Change   -118    k   loss
Peripheral Seas   -28    k   loss
Central Seas__   -63    k   loss
Other Seas___   -26    k   loss
         
Peripheral Seas         
Bering _______   -0    k   loss
Baffin  Bay____   -9    k   loss
Greenland____   -20    k   loss
Barents ______    0    k   gain
         
CAB Seas         
Beaufort_____   -0    k   loss
CAA_________   -4    k   loss
East Siberian__   -18    k   loss
Central Arctic_   -17    k   loss
         
Kara_________   -23    k   loss
Laptev_______    7    k   gain
Chukchi______   -8    k   loss
         
Other Seas         
Okhotsk______    1    k   gain
St Lawrence___   -0    k   loss
Hudson Bay___   -27    k   loss

Area loss 118 k, 32 K MORE than the 2010's average loss of 86 k on this day.
EDIT
Total area 3rd 4th lowest 5th lowest, (31k greater than 2007, 74k greater than 2016, and 220k greater than 2012).

2012 is the front runner as regards area.
Other Stuff
Until the weekend GFS showing  temperature anomalies at +0.9 to +1.9 degrees celsius. During this time the images suggest high +ve anomalies in central and eastern Siberia, with contrasting and sometimes strong -ve anomalies for most of the time on land and coastal sea by and in the Beaufort/CAA and Western Siberia, and in contrast again mostly +ve anomaly over most of the Arctic Ocean.

Over the weekend the picture changes somewhat. By Monday the CAA gets warmer, NW Canada and Alaska get a lot colder, and on the Russian side warmth moves west into areas bordering the Laptev and Kara, while the ESS area switches from strong warmth to a cold snap. However, over the Arctic Ocean itself there is a modest +ve  temp anomaly. Overall the Arctic temp anomaly stays well below 1 degree celsius.

A complicated picture.

We are in the period of maximum daily area loss that lasts until late July.
Area losses have ticked up a lot in the last three days after retreating to well below average during the few days before.
________________________________________________________________________
Extent and area showing marked difference. See next post(s).

134
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 25, 2019, 09:13:56 AM »
JAXA ARCTIC EXTENT :-  9,597,909 km2(June 24, 2019)

- Extent is 5th 6th lowest in the satellite record.
- Extent loss on this day 61 k, 16 k less than the average loss on this day of 77 k.
- Extent loss from maximum 4,673 k, 134 k (3.0 %) greater than the average of 4,539 k loss from maximum by this day,
- On average 45.9% of the melting season done, with 81 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt would give a minimum of 4.26 million km2, 4th lowest in the satellite record, and 1.08 million km2 above the 2012 low of 3.18 million km2.
Looking at the last 5 years average remaining melt gives a result of 4.36 million km2, 6th lowest, and 1.18 million km2 above 2012.

Other Stuff

Until the weekend GFS showing  temperature anomalies at +0.9 to +1.9 degrees celsius. During this time the images suggest high +ve anomalies in central and eastern Siberia, with contrasting and sometimes strong -ve anomalies for most of the time on land and coastal sea by and in the Beaufort/CAA and Western Siberia, and in contrast again mostly +ve anomaly over most of the Arctic Ocean.

Over the weekend the picture changes somewhat. By Monday the CAA gets warmer, NW Canada and Alaska get a lot colder, and on the Russian side warmth moves west into areas bordering the Laptev and Kara, while the ESS area switches from strong warmth to a cold snap. However, over the Arctic Ocean itself there is a modest +ve  temp anomaly. Overall the Arctic temp anomaly stays well below 1 degree celsius.

A complicated picture.

We are now entering the period of maximum daily extent loss that lasts until mid or late July and then very gradually declines.
Apart from 2 days, over the last 3 weeks and more extent loss has been below or well below average.
_____________________________________________________________________
The volume data for June should be available by late next week. It will be interesting to see what has happened to volume and perhaps more importantly, thickness during this month.

135
Permafrost / Re: Arctic Methane Release
« on: June 23, 2019, 10:09:52 PM »
As the years go by, the length of time that the Laptev Sea is mostly open water has greatly increased. Obviously that increases the chances of significant ocean warming, and being so shallow, warming of the sea floor.

Obviously this is likely to accelerate melting of the permafrost lid. After reading all the papers my own guess is yes, it will happen, but how much and how quickly....... ?

136
Policy and solutions / Re: Carbon Capture and Storage (CCS)
« on: June 23, 2019, 09:17:47 PM »
Equinor, Statoil as was, is 67% owned by the citizens of Norway through the government. The rest is in the market. That gives some comfort.

Big business including fossil fuel companies are obviously moving into renewables in a big way, as are the big automotive manufacturers moving into EVs. Obviously the main motive is survival, closely followed by handouts from us via our Governments.

And while they are delivering the goods, we will be screwed (again).

Promises of a green energy jobs boom in Scotland are proving to be so much hot air
Kevin McKenna
The government stands accused of failing to protect workers as it sold off projects to EDF and other foreign firms.

Quote
There has been almost £5bn of investment in offshore renewables in Scotland that, if properly managed and negotiated, could amount to several thousand sustainable and skilled jobs. According to the GMB, only 100 temporary jobs currently derive from this. In this global sector, we are often taking a penknife to a gunfight, with foreign-owned outfits heavily backed by governments that underwrite losses.

https://www.theguardian.com/commentisfree/2019/jun/23/promises-of-green-energy-jobs-boom-in-scotland-so-much-hot-air

And as a "screwee" my wish for those who are doing it to us is - to die soon, to die slowly, and to die in great pain.

137
Arctic sea ice / Re: The 2019 melting season
« on: June 23, 2019, 09:42:42 AM »

Polynya = cracks?

https://en.wikipedia.org/wiki/Polynya

Open water with sea ice around it? When I used the term that's what I meant - maybe I should stick to English   ;D
Tor Bejnar posted this on the SMOS thread

I don't recall ever seeing the term "flaw polynya" before, and it took some searching to find a definition, finally (from here):
Quote
flaw polynyas (band-like ice-free areas), which form
simultaneously with land-fast ice in November. Flaw polynyas
reach tens of kilometres in width and migrate out of fast ice
hundreds of kilometres northward (Smolyanitsky et al., 2003),
and here
Quote
A polynya is defined as any nonlinear-shaped area of open water and/or sea ice cover < 30 cm thick enclosed by a much thicker ice cover (WMO 1970). It can be restricted on one side by a coast, terrned shore polynyas, or bounded by fast ice, termed flaw polynyas.

138
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 23, 2019, 09:09:12 AM »
JAXA ARCTIC EXTENT :-  9,728,067 km2(June 22, 2019)

- Extent is 5th lowest in the satellite record.
- Extent loss on this day 87 k, 13 k more than the average loss on this day of 74 k.
- Extent loss from maximum 4,543 k, 156 k (3.6 %) greater than the average of 4,387 k loss from maximum by this day,
- On average 44.4% of the melting season done, with 83 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt would give a minimum of 4.23 million km2, 4th lowest in the satellite record, and 1.05 million km2 above the 2012 low of 3.18 million km2.
Looking at the last 5 years average remaining melt gives a result of 4.34 million km2, 6th lowest, and 1.16 million km2 above 2012.

Other Stuff

GFS showing  temperature anomalies at +1.0 to +2.1 degrees celsius  during the next week. The images suggest high +ve anomalies in central and eastern Siberia, with contrasting and sometimes strong -ve anomalies for most of the time on land and coastal sea by and in the Beaufort/CAA and Western Siberia, and in contrast again mostly +ve anomaly over most of the Arctic Ocean. A complicated picture.

We are now entering the period of maximum daily extent loss that lasts until mid or late July.
Until the last 2 days, over the last 2 weeks and more extent loss has been below or well below average.

Will above average daily extent loss be sustained?
Will area loss follow suit and return to at least average daily loss levels?

139
June 2019 SIPN report is out:
https://www.arcus.org/sipn/sea-ice-outlook/2019/june

Tealight (Nico Sun) has been very busy. Look for "Sun" in the tables and and images in the report.

Extract from his submission on SIE September Monthly Average.
Median 4.40
Ranges 3.73-4.88 Standard Deviations
His submission also tells you how he did it and the equations he used.

I wonder what Tealight has come up with so far for the JAXA daily extent minimum (and NSIDC and/or AMSR2 area).

Heuristic Estimates

The image from the report attached summarises the results by method, one of which is "heuristic" defined by Wikipedia as follows.
Quote
A heuristic technique (/hjʊəˈrɪstɪk/; Ancient Greek: εὑρίσκω, "find" or "discover"), often called simply a heuristic, is any approach to problem solving or self-discovery that employs a practical method, not guaranteed to be optimal, perfect, logical, or rational, but instead sufficient for reaching an immediate goal. Where finding an optimal solution is impossible or impractical, heuristic methods can be used to speed up the process of finding a satisfactory solution.

Heuristics can be mental shortcuts that ease the cognitive load of making a decision. Examples that employ heuristics include using a rule of thumb, an educated guess, an intuitive judgment, a guesstimate, profiling, or common sense.

Extract from a heuristic submission. I think the guy who did it is a hero for what he does. All credit to him for chucking in his submission.

"Executive summary" of your Outlook contribution (using 300 words or less) describe how and why your contribution was formulated. To the extent possible, use non-technical language.

email rec'd 11:00 pm (AKDT) on12 June: Hi Betsy, Well we just got back from the historic last
C-130H mission from USCG Air Station Kodiak. The long serving Hs are being replaces by the
C-130J model. Our Seasonal Ice Zone Reconnaissance Survey (SIZRS) flight was successful.
We flew up 150°W making oceanographic stations with expendable probes every degree fro 72
to 76 and then flew back at higher altitude doing atmospheric dropsonde drops. Notable ice
observations are that the ice edge has already retreated to 72°N and there was a lot of open water even up to 76°. The snow is already gone.

I usually try to do a little more analysis of trends for the year around the Arctic Ocean and look at the AO, but no time for that; it’s already midnight Pacific Daylight Time. To be any later and still be on the 12th, I’d have to be in Hawaii. So after exhausting if not exhaustive deliberation with my SIZRS colleges over pizza at the last eatery still open Kodiak, and considering the ice we saw today, my fresh from looking out the window is 3.8 million square km average Sept 2019 ice extent. Method would be politely called heuristic, and as ever the outlook recognizes that this summer's weather trumps everything else and is for the most part unknowable.

Best regards, Jamie
______________________________________________________________
Marvellous. So from now on, when someone asks me how on earth I come to and/or justify a result or comment my answer will be "using heuristic techniques when examination of the various data sources". Sounds much better than "dunno, sorta guess".
_______________________________________________________

140
Antarctica / Re: Sea Ice Extent around Antarctica
« on: June 22, 2019, 11:25:50 AM »
JAXA ANTARCTIC Sea Ice Extent :  12,763,937  km2(June 21, 2019)

Extent gains suddenly increased strongly in the last 3 days .
However, 2019 remains lowest in the satellite record (for 71 days this year), extent now just 74 k below 2017 and 675k below 2018.

- Extent gain on this day 154k, 54 k more than the average gain of 100 k on this day.
- Extent gain from minimum is 10.339 million km2, 0.950 million km2 (8.4%) less than the average of 11.289 million km2 by this day,
- 70.6% of average extent gain done, with 87 days to the average date of maximum (16 Sept).

The Perils of Projections
Remaining average freeze of the last 10 years gives a max of 17.48 million km2, 0.58 million km2 less than 2017 (the record low maximum year).
______________________________________________________________________

141
Arctic sea ice / Re: Global sea ice area and extent data
« on: June 22, 2019, 07:19:52 AM »
JAXA Global Sea Ice Extent as at 21 June 2019 :  22,578,517 km2

In the last 2 weeks Arctic extent loss was well below average, and while Antarctic extent gain was up and down around the average. Extent remained lowest, now for 72 days this year, 66 days in a row.

But the last 3 days saw very high Antarctic Sea Ice gain, while in 2017 for those 3 days global extent dropped. As a result Global extent is now in 2nd place, 12 k above 2017, but 849 k below 2018.

- extent gain on this day 56 k, 26 k more than the the average gain of 30 k on this day,
- extent gain from minimum to date is 6.33 million km2, 1.13 million km2 (15%) less than the average gain of 7.46 milllion km2 by this day,
-on average 82,7% of extent gain done and 136 days to maximum, but before that there is a false maximum (in July) and a false minimum (in September) before the (usually) true maximum around the 4th of November.

The Perils of Projections
The last 10 years average remaining extent gain would give a maximum of 24.14 million km2,  0.5 million km2 more than the record low maximum in 2016 and 2nd lowest in the satellite record.

Being a combination of two separate pieces of data volatility is often very high. Confidence in any projection is even lower than normal. However, the JAXA extent data so far does not point to a change to the usual pattern of a false maximum in July, a false min in Aug/Sep and a final max in early November.

142
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 21, 2019, 09:38:16 PM »
I used to like this thread.
So did I.

143
A blob of snow on the Central Siberian shore, and directly opposite snow on the CAA and the Canadian mainland adjoining refuse to die. (and a tiny blob in the Torngat mountains and North East Canadian coast. The Quebec glacial sheet lives!)

144
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: June 21, 2019, 03:56:37 PM »
http://polarportal.dk/en/greenland/surface-conditions/ as at 20 June 2019

A bit to my surprise melt was even a bit stronger and very much above average, near the maximum for the year. Precipitation was again low in most of Greenland except for in the North West, which was enough to reduce daily SMB mass loss to average. Below average Albedo expanding to higher elevations in the interior.

My prediction that belongs to me is that melt, Friday to Sunday ahead is likely to moderate but perhaps still stay above average.. But perhaps from Monday onwards higher melt gain, even reaching the very far north?
 
Precipitation in the next week is looking like moderate precipitation in the NorthWest becoming more general across Greenland. At least on the fringes (i.e. at low altitude) some of this will fall as rain.

SMB mass loss to continue but at a more average rate?
_____________________________________________________
Note from DMI

When comparing melt with the surface mass balance under ”Daily change”, note that melting can occur without surface mass loss since the meltwater can refreeze in the underlying snow. Likewise, surface mass loss can occur without melting due to sublimation.

145
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 21, 2019, 03:28:09 PM »
The number of posts correlates with melting. The latest data seems extremely bad for ice. :)

It is inspiring to see real science in action, Aluminium.   One day someone will thank you for this.    :)
Ah.. but.. Cause & Effect ?

When there is a significant increase in melting there is lot more posting on the Arctic Sea Ice Area and Extent data thread. You see that also on the Global Sea Ice Area and Extent thread - perhaps even more strikingly. I also see that my graphs and tables get looked at a lot more on that thread at such times. Does the same thing happen on the Melting Season thread as people look to see why the sudden melt has happened? In this case the cause is melting almost immediately followed by a spike in postings?

Then there are the occasions when the melting season posts correctly predict the Panzer divisons blitzkreiging and blowtorching the Arctic. So the correlation works well.

Then there are also times when the weather models let the side down. So in this case a spike in postings presage following days of limited melt.

Not that I will be dragging through the history on these threads to quantify and then analyse the data. Nor would I be so cruel as to expect Aluminum to expand his interesting exercise into a major project, extending into all times of the year. (Winter is also getting very interesting as maxima reach new lows)

Back to the data.

146
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 10:18:06 PM »
Kara Area (to 19 June), Volume (to 15 June), Thickness (to 15 June)  attached.

Slow beginnings.

147
Policy and solutions / Re: Direct Air Capture (of Carbon Dioxide)
« on: June 20, 2019, 09:14:42 PM »
to kick this misconception into the bin is attached

One of many visualisations that have failed to understand the way energy is utilized.

Can you give us more detail rather than just a simple dismissal?

Let's assume, just for the sake of the argument, that 100x100 miles of solar panels would generate as many TWh of electricity as the US uses annually.  How much storage would it take to turn that output into a 24/365 reliable electricity source for the US?
--

Obviously a 100% solar feed is not optimal.  The best solution will involve wind and other renewables as their inclusion lowers the need for storage.  But just play along and explain your thinking regarding 100% solar and storage.
For goodness' sake. It was a simple visual. No-one is suggesting that a 100 x 100 mile solar plant will be built.

No-one is suggesting that wind is not a major source as well.

We all know various storage mechanisms will be required, batteries, hydro and maybe still some LNG plants as extra back-up.

We all know that utilities will need to change their grids and computerised management systems to deal with a new pattern of electricity production, storage and consumption.

Most of us on this forum know that we can get most of the way to zero-carbon electricity with the technology that already exists. (And that is known by many of the Republicans on Capitol Hill)

I also believe that carbon will have to be captured. The concern is that many of the solutions mooted will make new problems greater than the one they are supposed to solve.

And that's all I'm going to say about that

148
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 06:38:57 PM »
Amount of ice is defined not just by extent and area, but by the combination of area and thickness (and extent is really not needed). Thickness is missing here.

How on Earth anybody would properly conclude "more ice in general in that location" based on those couple graphs only - i honestly don't know. "Suspect"? Sure, doable. "Likely"? Perhaps. But for sure? Hell no.
Just for you..
- NSIDC Area,
- PIOMAS Volume,
- Thickness - PIOMAS Volume divided by NSIDC area

I think they all say a bit of a hiccup in Beaufort's record losses to date.

NOTE: Volume and thickness to 15th June, area to 19th June

149
Glaciers / Re: Glaciers worldwide decline faster than ever
« on: June 20, 2019, 04:19:23 PM »
Quote
"No, we ain't gonna lose all the glaciers by 2030.. three might last 'til 2050". Whoopee.
I agree with the sentiment, although on these threads we are often 'arguing' about when the first BOE will occur (for example), with a difference of opinion within a decade or so. These Montanan glaciers, albeit minor players in the scheme of things (unless you are in Glacier National Park or down stream), have scientists disagreeing on more than 2 decades.
Those Montanan glaciers are not going to have a good summer according to the weather people.
Nor will the Alaskan Glaciers or those lumps of ice on land on the islands of the CAA.

150
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 03:59:29 PM »
As others have said

This is going to happen at peak.

A question on the graph.  Intuitively, it seems like the 60 degree line should be in between the 90 and 30 degree lines.   Why is the 60 degree isolation lower than 30?
The impact of longer daylight hours is greater than the impact of the sun's lower angle on the heat per square metre on the surface. The brainiacs have produced loads of standard tables on it.

I tried doing some work on that but my brain said "you aren't a pure maths undergrad anymore". (And anyway I spent far too much time in the bar and the snooker room).

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