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Messages - gerontocrat

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1
Consequences / Re: Prepping for Collapse
« on: July 21, 2019, 06:35:55 PM »
Is 'collapse' meant only in human civilisation context?
It could mean the joke's on us.

"collapse of stout party". It is said to be the punchline of a certain kind of ponderous and verbose joke that’s characteristic of the nineteenth century. It signals that the victim has realised he has been bested and is wilting in embarrassment and chagrin.

Nature won, we lost.

2
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 21, 2019, 06:12:27 PM »
NSIDC daily extent

Starting on the 18th, the daily numbers became unavailable.

I get my data as follows..

go to https://nsidc.org/arcticseaicenews/sea-ice-tools/

scroll down a bit to find the excel files to download.

for the daily & 5 day NH and SH extents choose:-

1. All daily (single day and five-day trailing average) extent values in one file, updated daily (Sea_Ice_Index_Daily_Extent_G02135_v3.0.xlsx)

It has never ever been a problem except when NSIDC has a problem.

3
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 21, 2019, 03:50:04 PM »
On July 31, daylight hours at the North Pole will be more than one hour less than today.
Surely the North Pole receives 24 hours' daylight until the equinox, then switches to zero?
Correct - it was a bad joke - North Pole, Alaska (yes, it does exist).

The point is that it is one month after the solstice - in the very High Arctic summer is almost gone and a very brief fall is about to commence.

4
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 21, 2019, 03:37:02 PM »
Somewhat earlier in the melting season there was much about how the central seas of the Arctic were melting at an enormous rate. Attached is an analysis in my JAXA sea ice extent format of where we are on sea ice area of the 7 Central Seas - Tealight's "High Arctic".

The analysis is that area is 2nd lowest, average remaining melt would give a minimum of third lowest.

5
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 21, 2019, 03:17:07 PM »
NSIDC Total Area as at 20 July 2019 (5 day trailing average)  4,798,458 km2

Area loss remaining a bit below average.
                        
Total Area         
 4,798,458    km2      
-544,869    km2   <   2010's average.
-609,365    km2   <   2018
-1,313,904    km2   <   2000's average.
         
Total Area Change   -87    k   loss
Peripheral Seas   -18    k   loss
Central Seas__   -60    k   loss
Other Seas___   -8    k   loss
         
Peripheral Seas         
Bering _______    0    k   gain
Baffin  Bay____   -5    k   loss
Greenland____   -11    k   loss
Barents ______   -3    k   loss
         
CAB Seas         
Beaufort_____   -8    k   loss
CAA_________   -5    k   loss
East Siberian__   -15    k   loss
Central Arctic_   -15    k   loss
         
Kara_________   -8    k   loss
Laptev_______   -4    k   loss
Chukchi______   -6    k   loss
         
Other Seas         
Okhotsk______    0    k   gain
St Lawrence___   -0    k   loss
Hudson Bay___   -8    k   loss

- Area loss 87 k, 5 k LESS than the 2010's average loss of 92 k on this day.
- Total area 2nd Lowest, 313 k LESS than 2016, and 4 k MORE than 2012.

Area loss remains just below average, 2012 now lowest by a smidgeon, difference with with 2016 widening.

Other Stuff
On July 31, daylight hours at the North Pole will be more than one hour less than today.

What all this means for melt is.... ?

Oulook
We are in the period of maximum daily area loss that  is already gently sliding down. Overall, Area losses in July to date above average, but currently trending a trifle downwards.

It definitely was a steep downward slope that has now eased.

NSIDC 5 day Area did not continue in pole position for about one week/two weeks/the rest of July/the entire remaining melt season.
________________________________________________________________________
NSIDC daily extent loss just 46k on this day.

6
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: July 21, 2019, 12:52:31 PM »
http://polarportal.dk/en/greenland/surface-conditions/ as at 20 July 2019

Melt approaching a new maximum for the year. I am sure the persistence of this strong melt is unusual, as normally we just see short-term spikes.

Precipitation in central west coast, and as a result SMB (Surface Mass Balance) loss was just a bit more above average due to higher melt.

GFS Precipitation is still looking a bit weird. Over the next 2 to 3 days a little atmospheric river comes out of Hudson Bay, crosses Ellesmere Island and Baffin Bay and splats precipitation on the central West coast. On Monday night it stops, and outlook for the next 5 days and more looking   very dry over all Greenland.

Melt. Greenland looks as if it will cool down somewhat from next mid-week, though temperatures above freezing around most of the coast in the next week. The SST anomalies in Baffin Bay can only increase as the final scraps of sea ice melt out is completed.. High pressure has been, is, and will be stuck over Greenland until ....? This is likely to keep most of Greenland dry (apart from the West coastal fringe until Monday), and maybe sunny? Will melt moderate or stay high?

SMB mass change is a matter of which prevails, precipitation or melt. The 19th and 20th July was a classic demo of how although melt was well above average at the peak of the melting season, a bit of precipitation on just one part of the West coast sent SMB loss back to average.

It still looks likely the SMB graph will show above average SMB loss over the next few days after Monday due to low precipitation or perhaps rainfall at lower elevations along the West coast..

It seems clear (to me at least) 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 (now) hypothesis remains that in 2012, even though melt was spectacularly high, lack of precipitation was as or more important than melt in the unprecedented SMB loss that year.

At the moment 2019 is giving 2012 a run for its money (as it is for Arctic Sea Ice). How linked are they? If this melt declines to average will Arctic Sea Ice melt reduce as well (or vice-versa)?
_____________________________________________________
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.

7
Arctic sea ice / Re: Global sea ice area and extent data
« on: July 21, 2019, 12:38:36 PM »
Hi Gerontocrat,
sorry to report that the table in your last post appears to have been from the day before.
Whoops. Corrected

8
Arctic sea ice / Re: Global sea ice area and extent data
« on: July 21, 2019, 11:56:02 AM »
JAXA Global Sea Ice Extent as at 20 July 2019 :   22,604,544 km2

We are now in the period of extent losses towards the false minimum of late August / Early September


In the last four days a switch from High Antarctic gains and low Arctic losses to an Antarctic loss and high Arctic losses. In 4 days data switched from a daily gain of 113,000 km2 to a loss of over 300,000 km2 in 2 days.  A good demo of volatility that makes prediction of global sea ice even more of a mug's game.

Global extent in 1st place, 169 k below 2017, and 929 k below 2018.

- extent loss on this day 142 k, 127k different from the the average loss of 15 k on this day,
- extent gain from minimum to date is 6.36 million km2, 0.76 million km2 (10.7%) less than the average gain of 7.12 milllion km2 by this day,
-on average 78.9% of extent gain done and 107 days to maximum in early November.
 
We should have passed the false maximum of early July, and maybe this time we have...
For a bit less than 2 months more 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 24.51 million km2,  0.87 million km2 more than the record low maximum in 2016 and 2nd lowest in the satellite record.
_____________________________________________________________
ps: quote from stephan
Quote
From a statistics point of view - and we look at two sets of almost independent data (Arctic and Antarctic) - one would guess that gains on the one side make up with losses on the other side (or vice versa) and the daily change should much more follow the green (average) line than the bumpy up and down line (of 2017 or 2019).
Any ideas why this is so?
If it was truly random it would be like 2 people independently tossing a coin. Each time, 4 possibilities.
Heads +1, Tails -1.

HH = +1 +1 = 2
TT  = -1 -1 = -2
TH  = -1 +1 = 0
HT  = +1 -1 = 0
Does that mean that half the time variations from the average should cancel each other out?
Does that mean the graph suggests there is a connection between short-term changes in Arctic extent losses and Antarctic extent gains?

Or does it just mean I have muddied the waters even more?

9
Antarctica / Re: Sea Ice Extent around Antarctica
« on: July 21, 2019, 11:08:59 AM »
JAXA ANTARCTIC Sea Ice Extent :  15,628,582 km2(July 20, 2019)

July so far saw a run of high to extreme extent gains. And in the last 3 days crashed to an extent loss for 2 days in a row. This happens, not often, but it does happen. It happens more frequently as maximum ice approaches, probably due to the violent weather** and storms that can shift large amounts of thin ice at the fringes about.

2019 is now 2nd lowest in the satellite record, just 49 k above 2017 and 187 k below 2018.

- Extent loss on this day 48 k, a variation of 123 k from the average gain of 75 k on this day.
- Extent gain from minimum is 13.204 million km2, 0.250 million km2 (1.9%) less than the average of 13.454 million km2 by this day,
- 84.4% of average extent gain done, with 58 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 18.13 million km2, 3rd lowest in the satellite record, and 0.07 million km2 greater than 2017 (the record low maximum year).

Despite the last 3 days, this is still a significant upwards change in extent from the end of June.  Still a large chance of significant change - either way. ______________________________________________________________________
** apparently weather is not a forbidden word on this thread (yet).

10
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 21, 2019, 10:45:38 AM »
JAXA ARCTIC EXTENT :- 6,975,962 km2(July 20, 2019)

July extent loss to date still above average overall.
On average, more than two thirds of extent loss completed.

- Extent is 2nd lowest in the satellite record, extent is 24 k above 2011.
- Extent loss on this day 94 k, 4 k more than the average loss on this day of 90 k.
- Extent loss from maximum 7,295 k, 426 k (6.2%) greater than the average of 6,869 k loss from maximum by this day,
- On average 69.5% of the melting season done, with 55 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt would give a minimum of 3.96 million km2, 2nd lowest in the satellite record, and 0.78 million km2 above the 2012 low of 3.18 million km2.

Ice Melt Outlook The peak days of daily melt are  past. From now to minimum, on average daily extent loss will initially slowly reduce, this reduction in daily loss gradually increasing on the approach to minimum. 

The June volume data persuaded me to drop my minimum guesstimate to below 4 million km2 from exactly 4 million km2. A mistake, or not a mistake, or even an underestimate of melt to come? That will depend on the future weather.
______________________________________________________________

11
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: July 20, 2019, 08:41:15 PM »
Any response to my July 8 question?  (or refutation of my interpretation  :) )
I don't know.
Why they don't use +1SD & +2SD grey bands is a mystery.

But SMB is a result of melt (-) and precipitation (+) or (-) if rain and the model assumes run-off?
The 2019 data shows clearly that even moderate precipitation can overwhelm melt.
So maybe although 2012 had that huge melt it also had quite a lot of precipitation.

I tried to find some precipitation data  and tried a download from the world bank site https://climateknowledgeportal.worldbank.org/download-data

It was supposed to be a .csv file. It killed my spreadsheet and I had to restart the computer.
I am not having a good day.

And DMI are not renowned for replying to requests for info or data.
Some mysteries must remain a mystery unless someone else finds out.

12
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 20, 2019, 04:15:50 PM »
NSIDC Total Area as at 19 July 2019 (5 day trailing average)  4,885,824 km2

Area loss remaining a bit below average.
                        
Total Area         
 4,885,824    km2      
-553,535    km2   <   2010's average.
-622,906    km2   <   2018
-1,308,286    km2   <   2000's average.
         
Total Area Change   -82    k   loss
Peripheral Seas   -17    k   loss
Central Seas__   -54    k   loss
Other Seas___   -11    k   loss
         
Peripheral Seas         
Bering _______   -0    k   loss
Baffin  Bay____   -4    k   loss
Greenland____   -10    k   loss
Barents ______   -3    k   loss
         
CAB Seas         
Beaufort_____   -7    k   loss
CAA_________   -7    k   loss
East Siberian__   -16    k   loss
Central Arctic_   -9    k   loss
         
Kara_________   -11    k   loss
Laptev_______    1    k   gain
Chukchi______   -5    k   loss
         
Other Seas         
Okhotsk______   -0    k   loss
St Lawrence___   -0    k   loss
Hudson Bay___   -11    k   loss

- Area loss 82 k, 12 k LESS than the 2010's average loss of 94 k on this day.
- Total area Lowest, 304 k LESS than 2016, and 6 k LESS than 2012.

Area loss remains below average, difference with 2012 narrowing, with 2016 widening.

Other Stuff
Weather Due to unforeseen circumstances....
_______________________________________________________
Weather
by
Ambrose Bierce

Once I dipt into the future far as human eye could see,
And I saw the Chief Forecaster, dead as any one can be--
Dead and damned and shut in Hades as a liar from his birth,
With a record of unreason seldome paralleled on earth.

While I looked he reared him solemnly, that incandescent youth,
From the coals that he'd preferred to the advantages of truth.
He cast his eyes about him and above him; then he wrote
On a slab of thin asbestos what I venture here to quote--
For I read it in the rose-light of the everlasting glow:
'Cloudy; variable winds, with local showers; cooler; snow.'
_________________________________________________

What all this means for melt is.... ?

Oulook
We are in the period of maximum daily area loss that lasts until late July, but is already gently sliding down. Overall, Area losses in July to date above average, but currently trending downwards.

It definitely was a steep downward slope that has now eased.

NSIDC 5 day Area could/would/should/will/will-not continue in pole position for about one week/two weeks/the rest of July/the entire remaining melt season (delete as applicable).
________________________________________________________________________

13
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: July 20, 2019, 01:12:54 PM »
And from an earlier paper (2007)
Whither Arctic sea ice? A clear signal of decline regionally, seasonally and extending beyond the satellite record
Walter N. MEIER, Julienne STROEVE, Florence FETTERER
National Snow and Ice Data Center, University of Colorado, Boulder,

Highly edited extract follows:
________________________________________________________
Projections for ice-free conditions

Extrapolating the linear trend until the ice extent reaches zero is a naive method of projecting when ice-free conditions could occur (naive because it assumes that linear regression is always predictive, which it is not).

However, there is no reason to believe that the sea-ice trend is or will continue to be linear. Due to the sea-ice–albedo feedback, one would expect an accelerating trend, and in fact the recent acceleration in the downward trend is a tantalizing possible indication of this. Thus, two functions in addition to a linear fit have been used: a quadratic and an exponential (ex/3 was found to be a good fit).
Year range for fit       Function           First year ice-free
1953–2005               Linear               2106
                               Quadratic          2042
                               Exponential       2060

1979–2005               Linear               2101
                               Quadratic          2035
                               Exponential       2065
____________________________________________________
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/A08934F159B0622754A63FEC6BDDCC2C/S026030550025444Xa.pdf/whither_arctic_sea_ice_a_clear_signal_of_decline_regionally_seasonally_and_extending_beyond_the_satellite_record.pdf

14
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: July 20, 2019, 12:46:14 PM »
A lot of stuff on the thread about an article by Stroeve and Notz interpreted by people on the forum that the paper suggests an ice-free summer by around 2050.

Meanwhile, back in the day....

Arctic Sea Ice Extent Plummets in 2007 by BY J. STROEVE, M. SERREZE, S. DROBOT,
S. GEARHEARD, M. HOLLAND, J. MASLANIK, W. MEIER, AND T. SCAMBOS
Eos, Vol. 89, No. 2, 8 January 2008

Quote
While natural variability may instead stabilize the ice cover for the next few years, the long-term outlook is disturbing. All models evaluated in the Intergovernmental Panel on Climate Change Fourth Assessment Report show declining September sea ice from 1953 to 2006.

While these models point to a role of GHG forcing, as a group they significantly underrepresent the observed trend [Stroeve et al., 2007]. The reasons for this underrepresentation remain to be fully resolved, but overly thick ice in several of the models provides a partial explanation. Given these conservative model results, along with the remarkable events of 2007, our view is that a seasonally ice-free Arctic Ocean might be realized as early as 2030.

https://www.researchgate.net/profile/W_Meier/publication/248820158_Arctic_Sea_Ice_Extent_Plummets_in_2007/links/0deec535e81c7e2f09000000.pdf

15
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: July 20, 2019, 11:40:49 AM »
http://polarportal.dk/en/greenland/surface-conditions/ as at 19 July 2019

Melt quite a bit above average. Again concentrated in the West and the South. I am sure the persistence of this strong melt is unusual, as normally we just see short-term spikes.

Precipitation in central west coast, and as a result SMB (Surface Mass Balance) loss was only just above average.

GFS Precipitation is looking a bit weird. Over the next 2 to 3 days a ltlle atmospheric river comes out of Hudson Bay, crosses Ellesmere Island and Baffin Bay and splats pecipitation on the central West coast. On Monday night it stops, and outlook for the next 5 days and more looking   very dry over all Greenland.

Melt. Temperatures above freezing around most of the coast in the next week. The SST anomalies in Baffin Bay can only increase as the final scraps of sea ice melt out is completed.. High pressure has been, is, and will be stuck over Greenland until ....? This is likely to keep most of Greenland dry (apart from the West coastal fringe until Monday), and maybe sunny? This should help to maintain melt.

SMB mass change is a matter of which prevails, precipitation or melt. The 19th July was a classic demo of how although melt was well above average at the peak of the melting season, a bit of precipitation on just one part of the West coast sent SMB loss back to average.

It still looks likely the SMB graph will show above average SMB loss over the next few days after Monday due to low precipitation or perhaps rainfall at lower elevations along the West coast..

It seems clear (to me at least) 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 (now) hypothesis remains that in 2012, even though melt was spectacularly high, lack of precipitation was as or more important than melt in the unprecedented SMB loss that year.

At the moment 2019 is giving 2012 a run for its money (as it is for Arctic Sea Ice). How linked are they? If this melt declines to average will Arctic Sea Ice melt reduce as well (or vice-versa)?
_____________________________________________________
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.


16
Arctic sea ice / Re: Global sea ice area and extent data
« on: July 20, 2019, 10:57:05 AM »
JAXA Global Sea Ice Extent as at 19 July 2019 :  22,726,409 km2

We are now in the period of extent losses towards the false minimum of late August / Early September

The overall picture for July sea ice so far is
- Antarctic sea ice gain more above than below average,
- Arctic sea ice loss more above than below average,

And then in the last four days a switch from High Antarctic gains and low Arctic losses to an Antarctic loss and high Arctic losses. In 4 days daily change switched from a gain of 113,000 km2 to a loss of 166,000 km2.  A good demo of volatility that makes prediction of global sea ice even more of a mug's game.

Global extent in 2nd place, 70 k above 2017, and 855 k below 2018.

- extent loss on this day 166 k, 153k different from the the average loss of 13 k on this day,
- extent gain from minimum to date is 6.50 million km2, 0.64 million km2 (8.9%) less than the average gain of 7.13 milllion km2 by this day,
-on average 79.1% of extent gain done and 114 days to maximum in early November.
 
We should have passed the false maximum of early July, but....
For the next 2 months or a bit less 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 24.63 million km2,  0.99 million km2 more than the record low maximum in 2016 and 2nd lowest in the satellite record.

17
Antarctica / Re: Sea Ice Extent around Antarctica
« on: July 20, 2019, 10:34:36 AM »
JAXA ANTARCTIC Sea Ice Extent :  15,408,430 km2(July 15, 2019)

July so far saw a run of high to extreme extent gains. And in the last 2 days crashed to an extent loss. This happens, not often, but it does happen. 2019 is now 2nd lowest in the satellite record, 290 k above 2017 and 73 k below 2018.

- Extent loss on this day 46 k, a variation of 112 k from the average gain of 66 k on this day.
- Extent gain from minimum is 13.252 million km2, 0.124 million km2 (0.9%) less than the average of 13.375 million km2 by this day,
- 83.9% of average extent gain done, with 59 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 18.25 million km2, 3rd lowest in the satellite record, and 0.19 million km2 greater than 2017 (the record low maximum year).

This is a significant upwards change in extent from the end of June.  Still a large chance of significant change - either way. ______________________________________________________________________

18
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 20, 2019, 10:12:02 AM »
JAXA ARCTIC EXTENT :- 7,069,820 km2(July 19, 2019)

July extent loss to date still above average overall.
On average, more than two thirds of extent loss completed.

- Extent is 2nd lowest in the satellite record, extent is 75 k above 2011.
- Extent loss on this day 120 k, 41 k more than the average loss on this day of 79 k.
- Extent loss from maximum 7,201 k, 422 k (6.2%) greater than the average of 6,779 k loss from maximum by this day,
- On average 68.6% of the melting season done, with 56 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt would give a minimum of 3.97 million km2, 2nd lowest in the satellite record, and 0.79 million km2 above the 2012 low of 3.18 million km2.

Other Stuff
Weather
Current conditions:  There is a lot of weather in the Arctic.
Future conditions:  There will be a lot more weather in the Arctic.

What all this means for melt is.... ?

Ice Melt Outlook The peak days of daily melt are  past. From now to minimum, on average daily extent loss will initially slowly reduce, this reduction in daily loss gradually increasing on the approach to minimum. 

The June volume data persuaded me to drop my minimum guesstimate to below 4 million km2 from exactly 4 million km2. A mistake. or not a mistake, or even an underestimate of extent loss to come?
______________________________________________________________

19
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: July 19, 2019, 07:36:41 PM »
I do not think a linear trend extrapolated that far into the future is reliable.  The slope appears to have changed several times over the decades.  A Gompertz fit, as posted by others, appears to be a better fit, but it looks to flatten the curve too much.
I was taught that the gompertz or S curve is used to represent the way an event happens. A classic example is expenditure on a construction project. Costs are low at the beginning, (design, approvals etc,) accelerate in the middle as main construction takes off and slows down with fiddly finishing work at the end. We used it in doing budgets for capital expenditure programmes.
 
The curve is also usual when looking at the annual melt of the Arctic Ocean as a whole.  The melt speeds up as temperatures rise and slows down when temperatures cool down. The second reason for the gompertz curve being appropriate as a representation is that when looking at an individual sea, no matter how early it melts out, when sea ice drops below a certain amount, the percentage of the remaining sea ice lost each day remains very much the same, and therefore the absolute decrease in daily sea ice declines, creating the classic gompertz end of graph shape. But there is no reason to suppose that to be the case with immediate future years ice loss in the Arctic.

At the moment, the increase in CO2 atmospheric concentrations is accelerating. This is likely to accelerate the increase in atmospheric temperatures.
If, as expected, pollution decreases due to public opinion and decreased use of coal, this is also likely to accelerate the increase in atmospheric temperatures,. albeit temporarily.

Summer Sea ice extent minimum is still at 50 % of the 1979 value.
Winter Sea ice extent maximum is still at nearly 90 % of the 1979 value.

We are nowhere near the tail end of the event being progress to an BOE. So why should future years annual losses in Arctic sea ice decline in line with the tail end of a Gompertz curve?

The only thing that makes any sense to me is to start with the idea of what is going to happen to AGW in general and AGW in the Arctic in particular in the immediate future, i.e. the next 5 to 10 years. And that looks pretty grim to me. How you stick that into a curve is beyond me. I don't have a few cray computers to help me out, either.

20
Consequences / Re: Heatwaves
« on: July 19, 2019, 05:48:39 PM »
But not a record breaker..... (But in a few years might last a long, long time)

From Forbes.com  from the US National Weather Service...

Topline: An excessive and potentially dangerous heatwave is expected to grip much of the Midwest and East Coast on Thursday and through much of the weekend, with temperatures and humidity expected to reach record-highs and well into the triple digits.

The National Weather Service has issued an Excessive Heat Warning—the most serious heat-related alert—for several areas on Thursday. And even more are under a less serious Heat Advisory.

Excessive Heat Warnings are given when the heat index (the combined temperature and humidity, or the “feels like” temperature) is forecasted to reach 105 degrees Fahrenheit or higher. Additionally, low temperatures during the night are expected to reach record highs.
Heat killed more people last year than any other type of extreme weather, according to the NWS.

Kansas City: Kansas City, along with northwestern Missouri and northeastern Kansas, is currently under an Excessive Heat Warning, which will continue until 8 p.m. Saturday.

New York City: An Excessive Heat Warning will be in effect from noon on Friday to 8 p.m. Sunday.

Oklahoma City: An Excessive Heat Warning is currently in effect until 8 p.m. Wednesday. A Heat Advisory will be in effect from 11 a.m. to 8 p.m. Friday.

Chicago: The city of Chicago and all of DuPage, Cook and Kane Counties will be under an  Excessive Heat Warning from 10 a.m. Friday to 7 p.m. Saturday.

Louisville: Louisville and parts of central Kentucky are currently under an Excessive Heat Warning until 7 p.m. Sunday.

Detroit: Detroit is currently under an Excessive Heat Warning and will remain so until 8 p.m. Saturday.

Boston: The city of Boston and the entire state of Massachusetts will be under an Excessive Heat Warning from noon Friday to 8 p.m. Sunday.

Washington, D.C.: The Washington, D.C. region will be under a Heat Advisory from 11 a.m. to 9 p.m. Friday. The alert will be pushed up to an Excessive Heat Watch from Saturday morning to Sunday evening.

Central Pennsylvania: The region will be under an Excessive Heat Warning starting noon Thursday to 8 p.m. Saturday.

Philadelphia: Philadelphia is currently under an Excessive Heat Warning and will be until 10 p.m. Sunday.

Atlantic City: An Excessive Heat Warning has been issued for western, central and southern parts of New Jersey from noon Friday to 10 p.m. Sunday.

Delaware: The entire state of Delaware and nearby Ocean City, Maryland, will be under an Excessive Heat Warning from noon Friday to 10 p.m. Sunday.

Cedar Rapids, Iowa: All of eastern Iowa is under an Excessive Heat Warning until 7 p.m. Saturday.

Lincoln, Nebraska: Eastern and southern Nebraska are under an Excessive Heat Warning until 7 p.m. Saturday.

21
Arctic sea ice / Re: Northern Sea Route thread
« on: July 19, 2019, 05:05:56 PM »
That blasted cyclone plonked in the middle of the Arctic Ocean is still producing counter-clockwise winds at and along the Russian coast-line.

So the ice is melting but lumps of ice keep on getting shoved ice in the way.  Could block the route for a few days more until melt finally disposes of the clutter.

Skipper! Back to Stay in port!

gif plays 3 times then stops.

22
Arctic sea ice / Re: When will the Northwest Passage "open" in 2019?
« on: July 19, 2019, 05:00:52 PM »
I predicted the first half of August (I think).

Still 4 weeks left.
Might be needing every day.

gif plays 3 times and then dies.

Just to keep Tor happy/shut him up (delete as applicable or leave both)

click gif to play and it will never stop

23
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 19, 2019, 03:23:22 PM »
NSIDC Total Area as at 18 July 2019 (5 day trailing average) 4,967,682 km2

Area loss remaining a bit below average.
                        
Total Area         
 4,967,682    km2      
-563,885    km2   <   2010's average.
-643,430    km2   <   2018
-1,313,926    km2   <   2000's average.
         
Total Area Change   -76    k   loss
Peripheral Seas   -18    k   loss
Central Seas__   -45    k   loss
Other Seas___   -14    k   loss
         
Peripheral Seas         
Bering _______   -0    k   loss
Baffin  Bay____   -3    k   loss
Greenland____   -11    k   loss
Barents ______   -3    k   loss
         
CAB Seas         
Beaufort_____   -9    k   loss
CAA_________   -6    k   loss
East Siberian__   -12    k   loss
Central Arctic_   -6    k   loss
         
Kara_________   -8    k   loss
Laptev_______    1    k   gain
Chukchi______   -3    k   loss
         
Other Seas         
Okhotsk______   -0    k   loss
St Lawrence___    0    k   gain
Hudson Bay___   -14    k   loss

- Area loss 76 k, 21 k LESS than the 2010's average loss of 97 k on this day.
- Total area Lowest, 290 k LESS than 2016, and 11 k LESS than 2012.

Area loss dipping to well below average, difference with 2012 narrowing, with 2016 widening.

Other Stuff
Weather
GFS  showing temperature anomalies in the range +1.0 to 0 degrees celsius over the next 10 days. Negative temperature anomalies seem to be mainly in eastern Siberia, and later in the forecast period in Western Canada and the CAA.

Over the next few days it looks like a fairly significant low sits over the central Arctic Ocean north of Central / Eastern Siberia and elsewhere a high sits in the North Atlantic and another high over Greenland. The strongish anticlockwise winds matching but opposite to the normal clockwise movement of the Beaufort Gyre are maintained, starting as strong northerly winds from the CAA and the North Greenland coast. Wind and rain also from the South up Baffin Bay into the CAA at least for the first few days.

GFS suggests that after a few days this pattern starts to decay, lows from the North Pacific start to enter the Arctic through the Bering Strait, presumably bringing warmth, moisture and even waves.

What all this means for melt is.... ?

A cliff or not a cliff** See below
We are in the period of maximum daily area loss that lasts until late July.
Overall, Area losses in July to date above average, but trending downwards.

It is definitely was a steep downward slope that has now eased.

The ESS was not a slope, or a cliff. It was a yawning abyss, but has the yawn bottomed out? Pretty much

NSIDC 5 day Area could/would/should/will/will-not continue in pole position for about one week/two weeks/the rest of July/the entire remaining melt season (delete as applicable).
________________________________________________________________________
Extent loss up by a lot for a second day.

24
Arctic sea ice / Re: The 2019 melting season
« on: July 19, 2019, 02:45:43 PM »
How does DMI see ice that is over 2 and 3 meters thick in the region I circled?
Its all rubble...

Don't know.
Don't care.
Don't matter.

25
Arctic sea ice / Re: The 2019 melting season
« on: July 19, 2019, 02:34:47 PM »

DMI volume is not at a record low. It is currently third lowest in record, unless I missed some year.
18 july 2012 : 6902 km3
18 july 2008 : 8010 km3
18 july 2019 : 8391 km3.

But it seems to be at its lowest since 2013, and more than 2000km3 lower than 2018, confirming recent important downward trend, and important melting in june, and july so far.

http://ocean.dmi.dk/arctic/icethickness/txt/IceVol.txt

Poxy DMI graph does not show 2012. That didn't help.

26
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 19, 2019, 01:44:15 PM »
An average melt won’t break records - just like an average 2012 wouldn’t have from here. It takes something exceptional to break records - with seven years of additional CO2 and heat, that something may not need to be quite as exceptional as 2012 - but still exceptional, IMO.
When just an average of the last 10 years melt from now would produce a 2nd lowest extent (and area) it does tell you the ice is in a pretty bad state.

It will only need area loss from now to be above average by 9% to produce a new record area low.

If volume loss from 30 June to minimum is merely average, volume will be lowest in the satellite record by a whopping 10%.

When things look dodgy even in a year that is not exceptional, you know the ice is not looking in good shape..

27
Consequences / Re: Prepping for Collapse
« on: July 19, 2019, 12:28:52 PM »
It is obvious that having a source of energy such as solar power, however limited in power and varying availability at different times of the year, is a damn sight better than not having it at all.

And using solar power for air conditioning is dumb. You can have windows that open and shut. You can adjust your life style to the climate. I worked close to the lakeshore in Malawi for nearly 4 years in the years B.A.C. (Before Air Conditioning). Although it was not official any more, essentially in the hot season we worked what was known as Hot Station Hours. Unlike the words of the song, we Mad Dogs and Englishmen did not go out in the mid-day sun.

The siesta is a practical adjustment to climate, not a symbol of laziness as believed by ignorant North Europeans.

28
Arctic sea ice / Re: The 2019 melting season
« on: July 19, 2019, 12:07:59 PM »
ok, Mr. Seaicesailor. Your irrational assault started just after Neven announced, so perhaps you are the one taking advantage. But you are right Sailor. I won't post here ever again Mr. Potty.
Bye.
Thomas Barlow
Nobody is assaulting you, certainly I didn't. I just pointed out, as a well-intentioned comment with a winky emoticon, that you are naughty by using that model that I don't trust, so you may want to deal with your angers in a different way. Bye.
PS. I have nothing to do with Mr. Potty. You almost look paranoid. I just signed in a few days ago, I have been in a hiatus for two years and perhaps wanted to contribute commenting about this strong melting season.
s.i.s.
Keep on sailing, Sailor.

The DMI thickness / volume model has few fans. It may be wrong, but it is consistently so, so I do look at it from time to time for trends, not absolute values. And at the moment the trend for volume in July is a continuation of the June trend, i.e. a record low. That trend is consistent with the June volume from PIOMAS.

So another piece of data suggesting that no matter what extent and area may say, Arctic Ice is in a bad way this year. There are no absolutes in any Arctic measures. We are damn lucky to have any at all. Link below...

https://forum.arctic-sea-ice.net/index.php/topic,2750.msg205984.html#msg205984

29
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: July 19, 2019, 07:08:39 AM »
http://polarportal.dk/en/greenland/surface-conditions/ as at 18 July 2019

Not a lot changed in this post except the date (which I remembered to change this time).

Melt at a little bit above average. Again concentrated in the West and the South. I am sure the persistence of this strong melt is unusual, as normally we just see short-term spikes.

Precipitation low, and as a result SMB (Surface Mass Balance) loss was above average.

GFS Precipitation outlook for the next 5 days still looking  like very dry over East Greenland, but with increasing chance of moist warm winds from the south into Baffin Bay bringing rain and warmth to the West coast.

Melt. Temperatures above freezing around most of the coast in the next week. The SST anomalies in Baffin Bay can only increase as the final scraps of sea ice melt out is completed.. High pressure has been, is, and will be stuck er Greenland until ....? This is likely to keep most of Greenland dry (apart from the West coastal fringe), and maybe sunny? This should help to maintain melt.

SMB mass change is a matter of which prevails, precipitation or melt. It still looks likely the SMB graph will show above average SMB loss over the next few days due to low precipitation or perhaps rainfall at lower elevations along the West coast..

It seems clear (to me at least) 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 remains that in 2012, even though melt was spectacularly high, lack of precipitation was as or more important than melt in the unprecedented SMB loss that year.

At the moment 2019 is giving 2012 a run for its money (as it is for Arctic Sea Ice). How linked are they? If this melt declines to average will Arctic Sea Ice melt reduce as well (or vice-versa)?
_____________________________________________________
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.

30
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 19, 2019, 06:38:27 AM »
JAXA ARCTIC EXTENT :- 7,189,518 km2(July 18, 2019)

After 6 days of well below average extent loss, another day of above average extent loss.
On average, more than two thirds of extent loss completed.

- Extent is 2nd lowest in the satellite record, extent is 130 k above 2011.
- Extent loss on this day 134 k, 48 k more than the average loss on this day of 86 k.
- Extent loss from maximum 7,082 k, 382 k (5.7%) greater than the average of 6,700 k loss from maximum by this day,
- On average 67.8% of the melting season done, with 57 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt would give a minimum of 4.01 million km2, 2nd lowest in the satellite record , and 0.83 million km2 above the 2012 low of 3.18 million km2.

Other Stuff
Weather
GFS  showing temperature anomalies in the range +1.0 to 0 degrees celsius over the next 10 days. Negative temperature anomalies seem to be mainly in eastern Siberia, and later in the forecast period in Western Canada and the CAA.

Over the next few days it looks like a fairly significant low sits over the central Arctic Ocean north of Central / Eastern Siberia and elsewhere a high sits in the North Atlantic and another high over Greenland. The strongish anticlockwise winds matching but opposite to the normal clockwise movement of the Beaufort Gyre are maintained, starting as strong northerly winds from the CAA and the North Greenland coast. Wind and rain also from the South up Baffin Bay into the CAA at least for the first few days.

GFS suggests that after a few days this pattern starts to decay, lows from the North Pacific start to enter the Arctic through the Bering Strait, presumably bringing warmth, moisture and even waves.

What all this means for melt is.... ?

Ice Melt Outlook
We are now in the last two weeks of the period of maximum daily extent loss that lasts until the end of July and then very gradually declines. Immediate weather outlook suggests a cooler Arctic, but then?

The June volume data persuaded me to drop my minimum guesstimate to below 4 million km2 from exactly 4 million km2. A mistake. or not a mistake, or even an underestimate of extent loss to come?
______________________________________________________________

31
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 18, 2019, 03:46:05 PM »
NSIDC Total Area as at 17 July 2019 (5 day trailing average) 5,044,111  km2

Area loss remaining a bit below average.
                        
Total Area         
 5,044,111    km2      
-581,612    km2   <   2010's average.
-665,756    km2   <   2018
-1,326,616 km2   <   2000's average.
         
Total Area Change   -93    k   loss
Peripheral Seas   -14    k   loss
Central Seas__   -61    k   loss
Other Seas___   -18    k   loss
         
Peripheral Seas         
Bering _______    0    k   gain
Baffin  Bay____   -3    k   loss
Greenland____   -9    k   loss
Barents ______   -2    k   loss
         
CAB Seas         
Beaufort_____   -9    k   loss
CAA_________   -5    k   loss
East Siberian__   -13    k   loss
Central Arctic_   -19    k   loss
         
Kara_________   -6    k   loss
Laptev_______   -3    k   loss
Chukchi______   -5    k   loss
         
Other Seas         
Okhotsk______    0    k   gain
St Lawrence___    0    k   gain
Hudson Bay___   -19    k   loss

- Area loss 93 k, 10 k LESS than the 2010's average loss of 103 k on this day.
- Total area Lowest, 296 k LESS than 2016, and 16 k LESS than 2012.

Area loss dipping below average, difference with 2012 narrowing, with 2016 widening.

Other Stuff
Weather
GFS  showing temperature anomalies in the range +1.0 to 0 degrees celsius over the next 10 days. Negative temperature anomalies seem to be mainly in eastern Siberia.

Over the next 5 days it looks like a fairly significant low sits over the central Arctic Ocean north of Central / Eastern Siberia and elsewhere a high sits in the North Atlantic and another high over Greenland. The strongish anticlockwise winds matching but opposite to the normal clockwise movement of the Beaufort Gyre are maintained, starting as strong northerly winds from the CAA and the North Greenland coast. Wind and rain also from the South up Baffin Bay into the CAA at least for the first few days.

GFS suggests that after a few days lows from the North Pacific start to enter the Arctic through the Bering Strait, presumably bringing warmth, moisture and waves. This would be a big change.

What all this means for melt is.... ?

A cliff or not a cliff** See below
We are in the period of maximum daily area loss that lasts until late July.
Overall, Area losses in July to date above average, but trending downwards.

It is definitely was a steep downward slope that as now eased.

The ESS was not a slope, or a cliff. It was a yawning abyss, but has the yawn bottomed out? Pretty much

NSIDC 5 day Area could/would/should/will/will-not continue in pole position for about one week/two weeks/the rest of July/the entire remaining melt season (delete as applicable).
________________________________________________________________________
Extent loss up on this day.

32
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: July 18, 2019, 07:09:34 AM »
http://polarportal.dk/en/greenland/surface-conditions/ as at 17 July 2019

Not a lot changed in this post except the date (which I remembered to change this time).

Melt at a little bit above average. Again concentrated in the West and the South. I am sure the persistence of this strong melt is unusual, as normally we just see short-term spikes.

Precipitation low, and as a result SMB (Surface Mass Balance) loss was above average.

GFS Precipitation outlook for the next 5 days still looking  like very dry over East f Greenland, but with increasing chance of moist warm winds from the south into Baffin Bay bringing rain and warmth to the West coast.

Melt. Temperatures above freezing around most of the coast in the next week. The SST anomalies in Baffin Bay can only increase as the final scraps of sea ice melt out is completed.. High pressure has been, is, and will be stuck over Greenland until ....? This is likely to keep most of Greenland dry (apart from the West coastal fringe), and maybe sunny? This should help to maintain melt.

SMB mass change is a matter of which prevails, precipitation or melt. It still looks likely the SMB graph will show above average SMB loss over the next few days due to low precipitation or perhaps rainfall at lower elevations along the West coast..

It seems clear (to me at least) 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 remains that in 2012, even though melt was spectacularly high, lack of precipitation was as or more important than melt in the unprecedented SMB loss that year.

At the moment 2019 is giving 2012 a run for its money (as it is for Arctic Sea Ice). How linked are they? If this melt declines to average will Arctic Sea Ice melt reduce as well (or vice-versa)?
_____________________________________________________
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.

33
Arctic sea ice / Re: 2019 vs 2012
« on: July 18, 2019, 06:52:27 AM »
...2012 extent... Remaining ice, though definitely at a record low, was not completely a freak event.

This is a Straw Man argument. I can't recall anyone claiming a freak accident, or even implying it or anything like it.

I get the sense you are responding to my points primarily -

Er, no, I was not. Nor to anybody else's. I was responding to that I noticed that while 2012 extent minimum was 800,000 km2 (20%) less than 2016 (the 2nd lowest year), area minimum was only 200,000 km2 (5%) less than 2016, i.e. simply following up my own observation.

Looking at the graphs suggested that this happened in August, and during the GAC. So I had a look at what happened in August to extent and area. The answer was that low concentration ice was destroyed and the remaining ice was left as a compact triangle. Hence area decreased far less than extent and dispersion decreased, instead of increasing until minimum as is "normal".

That makes 2012 very unusual, perhaps unique in the satellite record, freakish, if not a freak. I am debating with myself the extent of 2012's freakishness, not with anyone else. Extent loss from now to minimum in 2012 was 28% more than average, far more than any other year. Freaky. Area loss from now was just 8% above average, not freakish at all.

So 2012 is like the Curate's Egg, freakish in parts.

34
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 18, 2019, 06:17:06 AM »
JAXA ARCTIC EXTENT :- 7,323,641 km2(July 17, 2019)

After 6 days of well below average extent loss, a day of above average extent loss.
On average, two thirds of extent loss completed.

- Extent is 2nd lowest in the satellite record, 172 k above 2011.
- Extent loss on this day 100 k, 9k more than the average loss on this day of 91 k.
- Extent loss from maximum 6,947 k, 333 k (5.0%) greater than the average of 6,614 k loss from maximum by this day,
- On average 66.9% of the melting season done, with 58 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt would give a minimum of 4.06 million km2, 3rd lowest in the satellite record , and 0.88 million km2 above the 2012 low of 3.18 million km2.

Other Stuff
Weather
GFS  showing temperature anomalies in the range +1.0 to 0 degrees celsius over the next 10 days. Negative temperature anomalies seem to be mainly in eastern Siberia.

Over the next 5 days it looks like a fairly significant low sits over the central Arctic Ocean north of Central / Eastern Siberia and elsewhere a high sits in the North Atlantic and another high over Greenland. The strongish anticlockwise winds matching but opposite to the normal clockwise movement of the Beaufort Gyre are maintained, starting as strong northerly winds from the CAA and the North Greenland coast. Wind and rain also from the South up Baffin Bay into the CAA at least for the first few days.

GFS suggests that after a few days lows from the North Pacific start to enter the Arctic through the Bering Strait, presumably bringing warmth, moisture and waves.

What all this means for melt is.... ?

Ice Melt Outlook
We are now in the period of maximum daily extent loss that lasts until the end of July and then very gradually declines. Immediate weather outlook suggests a cooler Arctic, but then?


The June volume data persuaded me to drop my minimum guesstimate to below 4 million km2 from exactly 4 million km2. A mistake?
______________________________________________________________
[/quote]

35
Arctic sea ice / Re: The 2019 melting season
« on: July 17, 2019, 08:22:55 PM »
Take as long as you need, Neven,  and a bit more. It is really tough even if expected.
Take care of yourself and yours.

Gerontocrat.

36
Consequences / Re: Prepping for Collapse
« on: July 17, 2019, 06:05:10 PM »
Most Governments in the Northern hemisphere already have their plans for dealing with these events. They were prepared during the Cold War - in the UK it was called Civil Defense, and were to allow Government to continue in the event of most of the population being nuked.

One sometimes wonders if Governments are dusting these old plans off, updating them, and checking out the old bunkers that still exist with a view to repair and upgrade.

37
Consequences / Re: Prepping for Collapse
« on: July 17, 2019, 05:55:42 PM »
Which pathogens are spread from dead corpses that poses such a big threat?
If you really want to know, read the attached from
https://www.who.int/diseasecontrol_emergencies/guidelines/risks/en/

But in the event of societal collapse, it is likely that bodies will be left to rot, and become a food source for rats, dogs, cats, crows and just about every carnivore and omnivore in a place near you. Even then that might not be so bad if you get over the stink.

The bacteria involved in decomposition are not dangerous, because living people already carry identical germs in their own bodies. The maggots and other insects, though revolting, also constitute no threat to public health. Rats do host fleas, which can transmit typhus, typhoid fever, plague, and other diseases. But rats endanger public health wherever they mingle with people: They are no more harmful when they feed on corpses than at any other time. Despite ancient fears of death’s “miasma,” the foul odor emitted by the body as it rots is innocuous.

In a very few cases, bacteria from corpses can cause illness when they contaminate drinking water in large quantities. This could be a problem where large quantities of bodies are decomposing near a water source.

So it is best to leave the bodies to rot where they are, and AVOID CONTACT. Leaving the city if it is in a state of collapse sounds a good option.

38
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: July 17, 2019, 05:28:55 PM »
Do you have a prediction on when Baffin Bay will melt out?   It is probably in the 2019 Melt thread, haven't looked there yet today....
Only scraps left now, anyway.

39
Arctic sea ice / Re: 2019 vs 2012
« on: July 17, 2019, 04:45:14 PM »
And by the way, when is comes to dispersion, 2019 at the moment is following 2012 pretty closely.

40
Arctic sea ice / Re: 2019 vs 2012
« on: July 17, 2019, 04:16:40 PM »
I thought to have another look at 2012, specifically August and the GAC. So no comparison with 2019.

You can see from the graph that in August extent reduced by far more than area. hence dispersion was greatly reduced.
You can see by the gif that the ice that remained at the end of August was far more compact than at the beginning.

That says to me that the 2012 extent minimum flatters to deceive. Remaining ice, though definitely at a record low, was not completely a freak event.


41
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 17, 2019, 03:18:50 PM »
NSIDC Total Area as at 16 July 2019 (5 day trailing average) 5,137,444 km2

Area loss slowing
                        
Total Area         
 5,137,444    km2      
-585,084    km2   <   2010's average.
-674,368    km2   <   2018
-1,327,186    km2   <   2000's average.
         
Total Area Change   -84    k   loss
Peripheral Seas   -15    k   loss
Central Seas__   -56    k   loss
Other Seas___   -14    k   loss
         
Peripheral Seas         
Bering _______   -0    k   loss
Baffin  Bay____   -4    k   loss
Greenland____   -8    k   loss
Barents ______   -3    k   loss
         
CAB Seas         
Beaufort_____   -5    k   loss
CAA_________   -5    k   loss
East Siberian__   -11    k   loss
Central Arctic_   -19    k   loss
         
Kara_________   -6    k   loss
Laptev_______   -2    k   loss
Chukchi______   -7    k   loss
         
Other Seas         
Okhotsk______    0    k   gain
St Lawrence___    0    k   gain
Hudson Bay___   -14    k   loss

- Area loss 84 k, 16 k LESS than the 2010's average loss of 100 k on this day.
- Total area Lowest, 287 k LESS than 2016, and 11 k LESS than 2012.

Area loss dipping below average, difference with 2012 narrowing, with 2016 widening.

Other Stuff
Weather
GFS  showing temperature anomalies in the range +0.9 to 0 degrees celsius over the next 10 days. Negative temperature anomalies seem to be mainly in eastern Siberia.

Over the next 5 days it looks like a fairly significant low sits over the central Arctic Ocean north of Central / Eastern Siberia and elsewhere a high sits in the North Atlantic and another high over Greenland. The strongish anticlockwise winds matching but opposite to the normal clockwise movement of the Beaufort Gyre are maintained, starting as strong northerly winds from the CAA and the North Greenland coast. Wind and rain also from the South up Baffin Bay into the CAA at least for the first few days. GFS suggests that in the last few days the winds weaken.

What all this means for melt is.... ?
Is this weather pattern there for the long-term?
A cliff or not a cliff** See below
We are in the period of maximum daily area loss that lasts until late July.
Overall, Area losses in July to date above average, but trending downwards.

It looks like Fram export has stalled, with most area losses in the arc from the ESS along the Russian shore and down to the Barents. The CAA melt is ahead of average.

It is definitely a steep downward slope starting to ease.

The ESS was not a slope, or a cliff. It was a yawning abyss, but is the yawn decreasing? YES

NSIDC 5 day Area could/would/should/will/will-not continue in pole position for about one week/two weeks/the rest of July/the entire remaining melt season (delete as applicable).
________________________________________________________________________
Extent loss also low on this day. A cool Arctic & not enough inclement weather to stir things up?

42
Consequences / Re: Prepping for Collapse
« on: July 17, 2019, 01:37:38 PM »

That's the reason why I propose eugenics to weed out psychopathic traits from the human gene pool. Mandatory sterilization and/or life in prison if they commit a crime. They can be distinguished from the rest of the population with brain scans so there will be no chance of harming an innocent person.

If people with your views ever get in charge,
God help us.

43
I can't believe there is still ice in the Hudson Bay. How is that even possible?

Temperatures around the bay are pretty much summer like (Churchill 28C today) and the sun is burning down on the ice. Its identical latitude as the Baltic Sea which would never ever have ice in mid July, no matter how cold the winter was.
Location, location, location.
Hudson Bay is in the north and to the east of centre of a big continent.
It gets horribly cold in winter. That part of the world is not called "the Barrens" for nothing.
Summer is horribly short, winter is horribly long.

Ice freezes to an average depth of about 1.6 metres in winter and is late to start melting.

Hudson Bay is one of the seas (there is more than one) that seem to have ignored AGW.

This year it has melted out very close to the 2010's average, a week or more earlier than last year.

In contrast, the Baltic is at the western edge of the European continent, and its climate is semi-maritime, Atlantic westerlies.

44
Policy and solutions / Re: Tesla glory/failure
« on: July 17, 2019, 11:13:20 AM »
I don't usually take notice of Tesla's share price, driven as it is more by rumour of glory and failure.

But it has been going up steadily recently. When something is happening steadily with/at Tesla, perhaps its time to take note.

45
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: July 17, 2019, 07:56:25 AM »
http://polarportal.dk/en/greenland/surface-conditions/ as at 15 July 2019

Almost nothing changed in this post except the date.

Melt at a little bit above average. Again concentrated in the West and the South. I am sure the persistence of this strong melt is unusual, as normally we just see short-term spikes.

Precipitation, very low, and as a result despite average melt SMB (Surface Mass Balance) loss was very much above average.

GFS Precipitation outlook for the next 5 days still looking  like very dry over most of Greenland, but with increasing chance of moist warm winds from the south into Baffin Bay bringing rain to the West coast.

Melt. Temperatures above freezing around most of the coast in the next week. The SST anomalies in Baffin Bay can only increase as final sea ice melt out is completed.. High pressure has been, is, and will be stuck over Greenland until ....? This is likely to keep most of Greenland dry (apart from the West coastal fringe), and maybe sunny? This should help to maintain melt.

SMB mass change is a matter of which prevails, precipitation or melt. It still looks likely the SMB graph will show above average SMB loss over the next few days due to low precipitation.

It seems clear (to me at least) 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 remains that in 2012, even though melt was spectacularly high, lack of precipitation was as or more important than melt in the unprecedented SMB loss that year.

At the moment 2019 is giving 2012 a run for its money (as it is for Arctic Sea Ice). How linked are they? If this melt declines to average will Arctic Sea Ice melt reduce as well (or vice-versa)?
_____________________________________________________
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.

46
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 17, 2019, 07:33:33 AM »
JAXA ARCTIC EXTENT :- 7,424,100 km2(July 16, 2019)

- Extent is 2nd lowest in the satellite record, 182 k above 2011.
- Extent loss on this day 72k, 16k less[/b] than the average loss on this day of 88 k.
- Extent loss from maximum 6,847 k, 324 k (5.0%) greater than the average of 6,523 k loss from maximum by this day,
- On average 66.0% of the melting season done, with 59 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt would give a minimum of 4.07 million km2, 3rd lowest in the satellite record , and 0.89 million km2 above the 2012 low of 3.18 million km2.

Other Stuff
Weather
GFS  showing temperature anomalies in the range +0.9 to 0 degrees celsius over the next 10 days. Negative temperature anomalies seem to be mainly in eastern Siberia.

Over the next 5 days it looks like a fairly significant low sits over the central Arctic Ocean north of Central / Eastern Siberia and elsewhere a high sits in the North Atlantic and another high over Greenland. The strongish anticlockwise winds matching but opposite to the normal clockwise movement of the Beaufort Gyre are maintained, starting as strong northerly winds from the CAA and the North Greenland coast. Wind and rain also from the South up Baffin Bay into the CAA at least for the first few days. GFS suggests that in the last few days the winds weaken.

What all this means for melt is.... ?
Is this weather pattern there for the long-term?

Ice Melt Outlook
We are now in the period of maximum daily extent loss that lasts until the end of July and then very gradually declines. Immediate weather outlook suggests a cooler Arctic.

Extent loss in the last few days well below average,, but area loss well above.

The June volume data persuaded me to drop my minimum guesstimate to below 4 million km2 from exactly 4 million km2. A mistake?
______________________________________________________________

47
Science / Re: 2019 CO2 emissions
« on: July 17, 2019, 12:19:09 AM »

Also, there is a lot methane trap in coal deposits and released during coal mining.  That isn't taken into account in the above discussion.
There are installations in urban locations in the UK that are still collecting methane emitted from coalmines closed down 30 years ago. About the only places you can still see a sign"National Coal Board".

I guess in the USA and elsewhere the old coal mines just burp the stuff into the sky.

48
Arctic sea ice / Re: The 2019 melting season
« on: July 17, 2019, 12:13:38 AM »
Most of us are, as usual, waiting for the PIOMAS mid-month numbers, making Wipneus numero uno in our  universe.

Wednesday?
Thursday?
Friday?
No mid-month update this month?

ps: That DMI graph coming from a model that has numerous question marks about it,  maintains that the decline in volume has continued in July.

49
The rest / Re: The Trump Presidency
« on: July 16, 2019, 10:10:29 PM »
Trump is a snake-oil salesman and stumbled on the snake-oil that got him to the White House.

He is a misogynist.
He is a racist.
He appeals to the worst in people.

He is not immoral. Immoral people defy morality.
He is amoral. Morality does not exist for him.

He has the instincts and desires of a dictator.
He cannot be trusted.

When he is finished the USA will be weaker.
If he gets a second term the damage will be severe.

One "good" consequence is that the moral and ethical bankruptcy of the US Political establishment has been exposed - because he is still the President.

Trouble is, a lot of people a long way from the US of A could end up as collateral damage.

50
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: July 16, 2019, 08:32:49 PM »
Here's a good explanation of why there isn't expected to be a "tipping point" in the event of a BOE from a 2018 paper by Julienne Stroeve and Dirk Notz.

https://iopscience.iop.org/article/10.1088/1748-9326/aade56/meta

Quote
Changing state of Arctic sea ice across all seasons
Julienne Stroeve and Dirk Notz 2018 Environ. Res. Lett. 13 103001

... The annual cycle of Arctic sea ice loss per ton of CO2 emissions ranges from slightly above 1 m2 throughout winter to more than 3 m2 throughout summer. Based on a linear extrapolation of these trends, we find the Arctic Ocean will become sea-ice free throughout August and September for an additional 800 ± 300 Gt of CO2 emissions, while it becomes ice free from July to October for an additional 1400 ± 300 Gt of CO2 emissions.

With current CO2 release, an additional 800 Gt takes 50 years (36 Gt annual release, 44% of which is retained in the atmosphere).

A good article though, and I would tend to agree with the conclusions.
Why agree with that methodology and not agree with this methodology?

VOLUME
Since 1980 the amount of CO2 in the atmosphere has risen by about 600GT
Summer volume minimum has decreased from about 17,000 GT to about 5,000 GT.

Thus 1 GT additional CO2 in the atmosphere equates to summer volume loss of 20GT.

To get to minimum therefore needs 5000 divided by 20 additional GT of CO2 in the atmosphere,. i.e. 250 GT.

Current rates of emissions of 36 GT and 44 % retained in the atmosphere gives 16 GT more CO2 in the atmosphere per annum.

That gives zero ice in 16 years, 2035.

Assuming 1 million km2 of area = 1,000 km3 of ice volume.
A BOE then requires volume to go down by 4,000 GT, which takes 13 years, i.e. 2032

But if volume continues on its current trend, minimum this year could be about 3,500 km3. That brings a BOE into the 2020's.

Looking that far in the future is a mug's game.
So I think the methodology I used is junk, and so is the one by Stroeve / Notz. I am amazed they came up with that. Linear extrapolations to 2050? C'mon.

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