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Messages - PragmaticAntithesis

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1
Arctic sea ice / Re: 2020/21 Freezing Season Predictions
« on: September 29, 2020, 05:35:09 AM »
Knowing how the season has started, I think we'll likely see a record low maximum, but not by much.

Somewhere around 13.7±0.3sqMm extent seems like a good ball park estimate for me.
A hair low, but close I think.

My prediction is three fold:
High probability      - 14.0-14.5, shaded towards the low end.
Medium probability - 13.75-14.25, shaded towards the middle.
Very high probability 13.75-14.5, of course.

It depends if the refreeze is more like 2019/2020 or 2017/2018.

Looking at the NOAA data there seems to be a natural limit driven by geography which I suspect lies between 14.0 and 14.5 million km2, which may be the range our winter max falls in for a while.

Annual minimum will continue to decline along with volume, and be driven more by how soon the melt season starts and how hot Siberia gets, and how early.

There also I'll predict, volume at max for sometime is going to plateau at around 20,000-23,000 km3 similarly, drifting down slowly to the high teens.  This year I'll place my bet on 21,000km3 +/- 250.

However, if we get the inflow from cyclones I'm half expecting, my estimate could be high by over 1000km3.

2
Arctic sea ice / Re: The 2020 melting season
« on: July 28, 2020, 02:49:56 PM »
Another quite large daily drop in area. We are now below 4 million km^2.


So extent losses are slowing, area losses are growing. 

(looks nervously at speedometer, tightens seat belt).

3
The politics / Re: Your 2020 US Presidential Election Map
« on: July 18, 2020, 03:01:29 AM »
P.A.,
Nicely done.  You should be his campaign manager, as you have a well thought out strategy.  If Clinton has done that, she might be running for re-election right now.

4
C'mon, not enough effort? That's not nice.

Let's review the thought process which got us here.

1) The initial observation which led to the question about the quantity of summer export export comes from your CAB volume charts. The observation that CAB volume loss is relatively stable during days 165-210 leads one to question how material and variable export during this period can be.

2) I did find Wipneus' Fram volume loss charts for the last three years and from this limited sample came up with an estimate of 25 k3 / month which I posted in the melting season thread.

3) I then asked in the stupid questions thread about efforts to quantify export and Rod posted a study which was more detailed and gave rise to a similar calculation as in #2.

4) Now you have posted another chart which seems to corroborate the numbers in #2 and # above. A typical year seems to export ~ 100 km3 through Fram in the summer.

It's a little disappointing that at no point is there any appreciation for the simple value of a good question. It was not zero effort to arrive at this point. It involved some thinking and resourcefulness and relied upon information that you are presenting in order to make the connection. 



5
Greenland and Arctic Circle / Re: Greenland 2020 Melting Season
« on: June 01, 2020, 04:58:27 PM »
The images available today from Sentinel-2 (and thus relative to yesterday) are not the best, but I wanted to give an image of the melt ponds in West Greenland and this image of the Nordenskiold Glacier, West Greenland (southern neighbor of Jakobshavn Isbræ), with a melt pond of almost two kilometers seemed interesting to me.

6
Consequences / Re: Places becoming less livable
« on: May 25, 2020, 08:49:29 PM »
How do you define overpopulation anyway? In nature it is the carrying capacity of the system. With humans this is different.

It is a developmental problem. Way back in the nineties aardrijkskunde/geography we had two theories. One said that areas would progress from simple production to more complicated processes. The other was the center periphery theory were the centre controls the periphery and that is more like the world we ended up with. Basically we never stopped exploiting Africa. See Moneyland for some examples.

Subsaharan africa does not follow the general trend but they never had reliable countries either so then you are back to family.

The african overpopulation is basically eurocentric BS. We just got there first and killed most of our forests long ago.

This is the 21st century. We have one planet and we are all one. It is disingenious to worry about african overpopulation while american  mining operations keep spewing methane (and russia and SA etc).



7
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: May 23, 2020, 03:31:14 PM »
NSIDC Total Area as at 22-May-2020 (5 day trailing average) 10,160,702 KM2         
         
Total Area         
 10,160,702    km2      
-458,979    km2   <   2010's average.
-108,116    km2   <   2019
-905,323    km2   <   2000's average.
         
Total Change   -105    k   loss
Peripheral Seas   -52    k   loss
Central Seas___   -53    k   loss
         
Peripheral Seas         
Okhotsk______   -3    k   loss
Bering _______   -9    k   loss
Hudson Bay___   -27    k   loss
Baffin  Bay____   -5    k   loss
St Lawrence___    0    k   gain
Greenland____   -5    k   loss
Barents ______   -2    k   loss
         
Central Arctic  Ocean Seas         
Chukchi______   -6    k   loss
Beaufort_____   -7    k   loss
CAA_________   -4    k   loss
East Siberian__    5    k   gain
Central Arctic_   -13    k   loss
Laptev_______   -10    k   loss
Kara_________   -17    k   loss
         
Sea ice area loss on this day 105 k, -41 k more than the 2010's average loss of 64 k         
         
- 2020 area is at position #2 in the satellite record.         
- 2020 Area is 459 k less than the 2010's average         
- 2020 Area is 905 k less than the 2000's average         
- 2020 Area is 180 k more than 2016         
- 2020 Area is -108 k less than 2019
         
___________________________________________         
I am used to commenting on how one or two seas in part of the Arctic are behaving. It is unusual in my experience to see the ice disappearing just about everywhere.

It is important to remember that the NSIDC Sea Ice Area data is the 5-day trailing average. So the 105k sea ice area loss is the average of the last 5 days - over half a million km2 of sea ice area gone in the last 5 days. This also means that as 105k is greater than in the previous 4 days, the 5-day daily area loss will stay high for the following 2-3 days even if the one-day loss slows.

_____________________________________________
ps: I'm feeling smug - I wrote the following sentence on the 11th May...
Watch this space for the unfolding of the Great 2020 Mid-May Melting Event ?
https://forum.arctic-sea-ice.net/index.php/topic,2975.msg263728.html#msg263728

8
Arctic sea ice / Re: The 2020 melting season
« on: May 21, 2020, 03:06:31 PM »
Welcome Butterflyy.
This theory is best discussed elsewhere. Note that its more extreme version (the "Quebec reglaciation") has been promoted all over the forum by a certain user  and is frowned upon by the new moderator.  8)

9
Consequences / Re: Temperature signals from Covid-19
« on: May 02, 2020, 05:50:33 PM »
Just a first look but smog can reduce photosynthetic productivity by 10-40% . Probably better sources out there but first article I found.

http://nbrienvis.nic.in/Database/1_2051.aspx

10
Consequences / Re: Temperature signals from Covid-19
« on: May 02, 2020, 05:13:18 PM »
There is an annual spring cycle of CO2 intake by phytoplankton and terrestrial plants . The CO2 absorbed by plants is released in the fall as those plants die. Drought can affect the amount of CO2 emissions and that is why El Niño shows up in the CO2 long term charts.
 Now this next part is pure conjecture but what if the sudden clear skies are promoting plant growth that we didn’t realize had been suppressed ? The signal should show up in atmospheric CO2 dropping more than would be expected from emissions drops incurred from Covid lockdown  reductions alone.
 





11
Arctic sea ice / Re: 2020 Melting Season Predictions
« on: April 28, 2020, 08:23:45 PM »
A prediction like this completely depends on the weather this season, but I'm gonna gamble on the worst case scenario, which is to beat 2012, and end up below 3 million km2.

First of all the clean air, and lack of contrails. That will not only influence the arctic directly, but also indirectly as Eurasian heatwaves move north. Like it happened last year, with record Greenland melt.

So Eurasian heatwaves will cause temperatures in the arctic to go up, above it's own extra insolation that it will get because of clean air.

The big question is if this will produce more clouds and storms. I'm guessing that more heat means more energy, and thus bigger storms. If we're unlucky, and we get storms that push out the ice through fram and the garlic press, then we'll surely break the record.

But what I'll be watching is hot pacific water entering deep into the CAB. I think that this will be a major problem this year. Pacific hot water will heat up even more with clean air and higher insolation. And more of that hot water is flowing into the arctic because of the slowdown of the AMOC. Which gives that water more speed to penetrate deeper into the CAB every year.

The ice in Chukchi sea is already very thin, with the Bering sea seemingly losing ice fast. So that's the side of the arctic I'll be watching this season. Together with the weather.

If it all turns against us, I can see us dropping below 3 million km2.


12
Arctic sea ice / Re: The 2020 melting season
« on: April 28, 2020, 12:36:52 PM »
According to my mining script regional conditions are poor compared to the last decade.

Would it be more informative if I changed how many years the current year is compared to. Maybe post-2012 instead?

I suggest an automatic ban from this thread after 3-strikes, because its the same every year in the melting/freezing threads. Not going to answer anything re this post that isnt related to the ice.

13
Arctic sea ice / Re: The 2020 melting season
« on: April 27, 2020, 11:28:23 PM »
According to Nico Sun's area calculations, we are back in spot #1 today.
And I think that's where we'll stay all season...

IMO, this is a low effort, no value added post. Someone should open a prediction thread for the non-science of guessing future weather events.

14
Arctic sea ice / Re: The 2020 melting season
« on: April 20, 2020, 04:39:56 AM »
Which reminds me of the very useful graph of FDDs by Nico Sun. This year was much better than the last few years, as the Arctic was colder during the winter, and volume is not running at a near-record level. Hopefully this will pay off with higher resistance to melting.

15
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: April 18, 2020, 03:40:49 PM »
Thank you again for these daily reports...come here every day to read them.

16
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: April 17, 2020, 07:04:57 AM »
Random thank you to Gerontocrat and Juan for the community service here. Your updates are a very important pillar of the community.

The last 5 years being the lowest 5 in terms of extent at this point in the calendar truly reflect the chronic progression of AGW.

17
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: April 17, 2020, 05:55:28 AM »
April 16th, 2020:
     13,001,987 km2, a drop of -58,088 km2.
     2020 is 2nd lowest on record.
     In the graph are the today's 25 lowest years (in order to include 2012).  ;)
     Highlighted the 4 years with September lowest min (2012, 2019, 2016, 2007) & 2020.
     Source: https://ads.nipr.ac.jp/vishop/#/extent

P.S. Today's difference [2012] - [2019] = 1,270,392 km2.
      And more that 1M km2 (2012 versus 2020). What a fall 2012 had!!!  ::)

18
The forum / Re: Who would like to take over the ASIF?
« on: April 09, 2020, 05:10:00 PM »
First, thank you Neven for this forum, my almost-only source of non-local news and where I've learned huge amounts of information over the years. Your guidance and moderation were great and your knowledge immense. With that said I did feel your emotional absence in the past few months, which was a bummer. So I understand your decision to bring in fresh troops.
I volunteer to help in moderation**. I am highly pressed for time as I often work 16 hours per day. But my work is in front of a computer or cellphone and leaves me time to read the ASIF in many spare moments. I used to read each and every post, now I lack the time for that, but I often "know" which posts are problematic or OT and which users should be booted or reprimanded.
I think the best thing would some kind of moderator group. I think highly of you blumenkraft and your many contributions, but I also sense a bit of impulsiveness and readiness to find a heated argument even where none need exist. Being sole moderator would not do you good and could harm the ASIF - every valued member we lose diminishes the forum, even if it's people who disagree with you (and even if they disagree with me!). And people take offense easily and have long memories.
Those we should lose are those who troll incessantly or who attack other people constantly. I am sure a majority would immediately agree on such rare actions.
Running the whole operation as chief - go for it blumenkraft, and good for us.
Moderation - I suggest a group of chief and 4 other moderators (if such are found), each with authority to edit on his/her own, but majority can overrule each single moderator, and majority required for banning users.

** My main qualification - I cover all 24 hours in a day...

19
The forum / Re: Who would like to take over the ASIF?
« on: April 09, 2020, 04:51:14 PM »
And i would like to be allowed to fight (snip) racism (of which there is too much on the forum IMHO).

I think your definition of racism is pretty skewed. Your heart is in the right place but you are hypersensitive about it. I remember the drama in this thread where you ended up calling Archimid a "nazi handmaiden" for merely pointing out the fact that there are certain medical differences between genetic populations, such as sickle cell prevalence: https://forum.arctic-sea-ice.net/index.php/topic,2996.msg249684.html#msg249684

If these are the kinds of posts that you would label as racism and remove, then I am against you being admin, if I am being honest.

20
Arctic sea ice / Re: The 2020 melting season
« on: April 07, 2020, 09:41:10 PM »
Methinks the US still isn't taking this seriously

As a humanitarian gesture the U.S. decided to allow American citizens abroad to return home to be with family and receive medical care if and when needed.
Unfortunately, one of the political parties refuses to allow changes to the chain migration laws under which non- citizen family members can come into the country to be reunited with existing American citizens.
My understanding is that from China alone 40,000 have been “repatriated”  to the U.S. to be with their brothers, cousins, uncles, grandparents etc. since the pandemic began.
The migration continues, even with the virus in the background.
Add that to the movement of consumer goods, food and medical equipment being sent from places with low virus issues to States where help is needed quickly and yes, the planes are still flying, though many less.
Many parts of the States are already beginning to see a flattening of the curve in regards to new cases and yes, it’s being taken very seriously in the U.S.
Back to the ice!

21
Arctic sea ice / Re: The 2020 melting season
« on: April 01, 2020, 11:26:57 AM »
There is also a thread When will the Arctic Go Ice Free? where I thought discussions about the BOE were to be held.

https://forum.arctic-sea-ice.net/index.php/topic,2348.msg253549.html#msg253549

Surely the 2020 melting season thread is about 2020? And 2020 will not see a BOE anyway - with ideal melting conditions maybe 1.5 million km2 below trend@ 2.5 million km2.

22
Arctic sea ice / Re: The 2020 melting season
« on: April 01, 2020, 08:21:50 AM »
moved to When Will Arctic Be Ice Free thread

23
Consequences / Re: Global recession
« on: March 28, 2020, 07:23:54 AM »
The Next Financial Crisis: A Collapse of the Mortgage System
https://www.politico.com/amp/news/2020/03/27/mortgage-system-collapse-coronavirus-pandemic-152338

The mortgage finance system could collapse if the Fed doesn’t step in with emergency loans...

But they will. As all other central banks. This time the financial system is not the core of the problem and can be handled relatively easily.

The service sector - which in most recessions a stabilizing factor - is collapsing. We need novel solutions for that problem, eg. (temporary) universal basic income, direct handouts to the population (happening in the US right now), government paying (part of the) wages instead of firms, etc. This is the bigger problem now.

24
Consequences / Re: Global recession
« on: March 24, 2020, 02:19:27 PM »

Is your faith in the ability of the growth dependent global finance system to remain stable in the face of ANY events truly infinite?

Not in ANY event surely, I can imagine scenarios that would make me think that there is no return (at least for many years). At the beginning of this outbreak in January I thought that mortality is 20+% and if that were true I think there would have possibly been civilizational collapse. Also, there are other scenarios that I can imagine that could cause collapse.

But I have seen quite a lot and now can safely draw the conclusions that:

- this virus can and will be beaten
- the recession caused by it is extremely, recordbreakingly deep, but managable
- governments and central banks have the tools to manage the financial system's underlying fragilities

Conclusion: I believe that 2020 will see a global recession but that will not turn into a depression and a breakdown of the financial system. We shall see one year from now who is right.

25
Arctic sea ice / Re: The 2020 melting season
« on: March 19, 2020, 08:21:03 PM »
Greetings from Midway Georgia,
 I've been lurking here for years, but after some 26 tears online, this the very 1st forum that I have ever joined.  This is my 5th attempt to make a post, so bear with me as i learn the ropes :)
 I've been alarmed by the huge export through Farm and subsequent melting signified by the foam left over from the melting ice in the GS as illustrated by the attached image.
 Also included in the image of some beautiful cloud vortices.  It's too bad that they overlay a field of death for ice

https://worldview.earthdata.nasa.gov/?v=348385.3212968977,-1205274.273347458,1466593.3212968977,-680986.2733474581&p=arctic&t=2020-03-18-T19%3A13%3A07Z

td

think good thoughts, do good deeds, enjoy good results


26
Arctic sea ice / Re: The 2019/2020 freezing season
« on: March 14, 2020, 10:26:56 PM »
Note to Neven: please make the new melting season thread sticky. Looking at extent and area numbers, the freezing season is over.

27
Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« on: March 13, 2020, 10:48:22 PM »
Also of note ELECTROVERSE are a bunch of gibbering cranks. links to such a source do not belong on this forum.

A few remarks:

First i posted without link. Even though I was reading on the solar minimum topic many pages from various sources recently, i remembered that you all are so much in love with links and decided to google for sun-spots and solar minimum.

The linked page states exactly what i true under this aspect, what else they do I DO NOT KNOW and I DO NOT CARE.

What you did is discourage me again to search for links. Without links you complain for the missing link and with link you complain about the source.

If you think that before posting a link that confirms what i already know or learned before I gonna search for detailed reviews of the page with that link, which is in vain because I would find quite all kind of opinions anyway, you can Kiss M. A.

In the future I won't translate with google's help just to hear about bad translation while the content as such and it's meaning are obvious and what counts and won't post links to hear about bad source and what belongs. I just say: "Hit & Run"

28
Arctic sea ice / The 2020 melting season
« on: March 13, 2020, 10:24:24 PM »
The last couple of days have seen a decline in the sea ice extent in Arctic, mostly confined to peripheral areas. Whether this downward trend is signaling the "onset" of the melting is an open question. However, we are in the middle of March and this year the upcoming weeks will probably be terribly slow for most of us. So, if Neven is OK with maning an exception for this year I hope we can start the discussions about the 2020 melting season.

The strong polar vortex that bottled up the cold air over the central Arctic basin should have strengthened the ice enough to make the 2020 minimum end up higher than the last few years. At least if we Have a moderately bad summer.

I hope everyone in here will be with us through the whole season and many more years ahead. Stay safe out there!

//LMV

<edit Neven: I don't have time to follow current events in the Arctic, so I can't assess whether it's too early for this thread or not, which means I'll leave it open. I did adjust the title though. If there's a second max, this is on you, LMV.  ;) >

29
Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« on: March 13, 2020, 09:55:36 PM »
A maunder minimum would drop temperatures by about 0.3C  15 years warming at our present rate of around 0.2C a decade.
Quote
it is certainly interesting to explore what effects such a minimum might have on 21st century climate if it did occur. This is precisely the question Stefan Rahmstorf and I investigated in a study published last year (see also our press release. (Earlier estimates for the size of this effect can be found here and here.) In our study we find that a new Maunder Minimum would lead to a cooling of 0.3°C in the year 2100 at most – relative to an expected anthropogenic warming of around 4°C. (The amount of warming in the 21st century depends on assumptions about future emissions, of course).
http://www.realclimate.org/index.php/archives/2011/06/what-if-the-sun-went-into-a-new-grand-minimum/

Also of note ELECTROVERSE are a bunch of gibbering cranks. links to such a source do not belong on this forum.
There are data sources that do not encourage visiting such sites and raising their profile on search engines.

30
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: March 10, 2020, 06:00:11 AM »
If the 2020 max happened on March 3rd, then 2020 is the year with the 10th lowest max.

Source: [ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.
https://ads.nipr.ac.jp/vishop/#/extent

31
Arctic sea ice / Re: The 2019/2020 freezing season
« on: March 09, 2020, 02:47:50 PM »
Don't forget the sea temperatures there, PA. If the ice is getting pushed south into warm waters, it will just melt away.


32
Arctic sea ice / Re: The 2019/2020 freezing season
« on: March 08, 2020, 02:14:35 PM »
Thanks for your understanding, PA!

This is the right thread. And soon it's the 20/21 melting season thread.

If you want to comment on something specific from the data thread, hit the quote button there, copy the text out of the text field, and then come here (or the melting season thread) and paste it.

33
Arctic sea ice / Re: The 2019/2020 freezing season
« on: March 04, 2020, 09:12:33 PM »
It's cold north of 80 latitude but warmer than average in the lower latitudes. Not a good pattern for the sea ice because the Fram export is high and the thick ice will leave anyway but the land snow is starting to melt more quickly

34
Consequences / Re: Global recession
« on: March 03, 2020, 07:01:19 PM »
From the coronavirus thread:

”The Federal Reserve announced an emergency rate cut Tuesday of half a percentage point in response to the growing economic threat from the novel coronavirus.
The move was the first such cut since December 2008, during the financial crisis.”

Fed cuts rates by half a percentage point to combat coronavirus slowdown
https://www.cnbc.com/2020/03/03/fed-cuts-rates-by-half-a-percentage-point-to-combat-coronavirus-slowdown.html

"Central banks are pulling out a playbook that was designed to deal with financial problems and not to deal with public health problems. So I really think they're like a fish out of the water here. They have no idea how to contain or even to understand what may be about to happen in the public health area or the U.S. economy's response to that."
Fed is a 'fish out of the water' in fight against coronavirus, former Morgan Stanley chief economist says
https://www.cnbc.com/2020/03/03/fed-is-a-fish-out-of-the-water-in-fight-against-coronavirus-former-morgan-stanley-chief-economist-says.html

35
Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« on: February 16, 2020, 07:12:04 PM »
Now that we are near the end of freezing season, I've noticed there are huge swings in daily extent gains, and even losses. Why is the behaviour of sea ice extent so wildly inconsistent around this time of year?

Why would you expect it to be stable? The ice can at this moment only expand into open ocean, where currents and contrary winds can and will cause large fluctuations. By far the biggest difference in extent from one day to another, and indeed from one year to another, during these winter months, is due to the vagaries of winds and have little or nothing to do with temperatures.

So, would I be correct in saying that the wind is blowing the ice around, which affects sea ice dispersion (and therefore extent) while sea ice volume remains relatively stable?
Yes, in the peripheral seas, though above freezing temperatures are being brought into the Southern Barents and Kara sea on occasion. In the main Arctic Ocean, temperatures are still well below that necessary for further ice thickening. Hence volume will likely max out in April.

36
Consequences / Re: Chinese coronavirus
« on: February 07, 2020, 02:39:55 AM »
We hear concerns that the Wuhan virus could be impacting the global economy. What with all the airline flights being cancelled, and with a reduction in industrial activity, we may be able to detect a Wuhan effect in global CO2 levels. Which would be a good thing, considering how rapidly it has been rising this year.

37
Antarctica / Re: Thwaites Glacier Discussion
« on: January 29, 2020, 09:46:44 AM »
More news/video from the Thwaites grounding zone:

https://schmidt.eas.gatech.edu/2019-field/firstlookunderthwaitesglacier/


38
Antarctica / Re: Sea Ice Extent around Antarctica
« on: January 14, 2020, 07:11:18 PM »
Oh, that's interesting. As freshwater has a much higher freezing point than saltwater, and its less dense (so stays on the surface), a freshening of the water would lead to much higher sea ice extent (enough higher to overpower the effects of AGW!).

I wonder if this trend will continue as glaciers melt more rapidly.
The surface melt is in addition to the influx of freshwater from sub-surface melting of the ice shelves and marine-terminating glaciers which is increased if the surface is covered in a layer of cold freshwater i.e. a classic feedback mechanism.

A battle between warmth moving south towards Antarctica and cold freshwater spreading north across the surface of the Antarctic Ocean?

Some links and extracts

https://www.carbonbrief.org/melting-antarctic-ice-could-slow-global-temperature-rise-study
Cold meltwater running off Antarctica’s ice sheets and into the ocean could dampen the pace of global temperature rise, a new study suggests.
Quote
The research, published in Nature, finds that the rate of ice-sheet melt in a high-emissions scenario could see the oceans cooled by the influx of frigid water. This could knock as much as 0.4C off global temperature rise, the researchers say, potentially delaying exceeding the 1.5C and 2C Paris temperature limits by around a decade.

However, the study adds that the meltwater could have wider impacts on the Earth’s climate, increasing the formation of Antarctic sea ice, reducing rainfall in the southern hemisphere and increasing rainfall in the northern hemisphere. It could also cause warming of the ocean beneath the surface layer around the Antarctic coast, the researchers add, leading to further ice-sheet melt and additional sea level rise.

Scientists not involved in the research tell Carbon Brief that while the results are intriguing, some caution is warranted given that the study relies on a single climate model. It also uses a speculative ice-melt scenario and focuses on a region – the Southern Ocean and Antarctica – which climate models can struggle to simulate accurately.

Additional work, including running similar simulations using other climate models and including the impact of meltwater from Greenland, may provide a more complete picture of the climate impacts of melting ice sheets, the scientists note.

Adding Antarctic meltwater to climate models
While climate models seek to include various different elements of the Earth’s systems, many are still limited in their modeling of changes in global ice sheets. While models include the role of ice melt on global sea level rise, they generally do not include the impact of the effect of meltwater from ice sheets and ice shelves on the climate

The broader climate impacts of ice-sheet and ice-shelf melt are not included in the current generation of climate models – CMIP5 – and are not expected to be accounted for in the upcoming CMIP6 models either.


https://www.ncbi.nlm.nih.gov/pubmed/30455421/
Change in future climate due to Antarctic meltwater
Quote
Meltwater from the Antarctic Ice Sheet is projected to cause up to one metre of sea-level rise by 2100 under the highest greenhouse gas concentration trajectory (RCP8.5) considered by the Intergovernmental Panel on Climate Change (IPCC). However, the effects of meltwater from the ice sheets and ice shelves of Antarctica are not included in the widely used CMIP5 climate models, which introduces bias into IPCC climate projections. Here we assess a large ensemble simulation of the CMIP5 model ‘GFDL ESM2M’ that accounts for RCP8.5-projected Antarctic Ice Sheet meltwater. We find that, relative to the standard RCP8.5 scenario, accounting for meltwater delays the exceedance of the maximum global-mean atmospheric warming targets of 1.5 and 2 degrees Celsius by more than a decade, enhances drying of the Southern Hemisphere and reduces drying of the Northern Hemisphere, increases the formation of Antarctic sea ice (consistent with recent observations of increasing Antarctic sea-ice area) and warms the subsurface ocean around the Antarctic coast. Moreover, the meltwater-induced subsurface ocean warming could lead to further ice-sheet and ice-shelf melting through a positive feedback mechanism, highlighting the importance of including meltwater effects in simulations of future climate.

https://www.cambridge.org/core/journals/annals-of-glaciology/article/effect-of-increased-fresh-water-from-antarctic-ice-shelves-on-future-trends-in-antarctic-sea-ice/3F0B83DB48A15767F77340ED0796AC66
The effect of increased fresh water from Antarctic ice shelves on future trends in Antarctic sea ice
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Observations show that, in contrast to the Arctic, the area of Antarctic sea ice has increased since 1979. A potential driver of this significant increase relates to the mass loss of the Antarctic ice sheet. Subsurface ocean warming causes basal ice-shelf melt, freshening the surface waters around Antarctica, which leads to increases in sea-ice cover. With climate warming ongoing, future mass-loss rates are projected to accelerate, which has the potential to affect future Antarctic sea-ice trends. Here we investigate to what extent future sea-ice trends are influenced by projected increases in Antarctic freshwater flux due to subsurface melt, using a state-of-the-art global climate model (EC-Earth) in standardized Climate Model Intercomparison Project phase 5 (CMIP5) climate-change simulations. Virtually all CMIP5 models disregard ocean–ice-sheet interactions and project strongly retreating Antarctic sea ice. Applying various freshwater flux scenarios, we find that the additional fresh water significantly offsets the decline in sea-ice area and is even able to reverse the trend in the strongest freshwater forcing scenario that can reasonably be expected, especially in austral winter. The model also simulates decreasing sea surface temperatures (SSTs), with the SST trends exhibiting strong regional variations that largely correspond to regional sea-ice trends.

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Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: January 09, 2020, 06:32:12 PM »
Yes Spring will tell the tale.

Id expect a lot of fast melt for a time as a lot of ice only a couple of months old due to late freezeup.

40
Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« on: December 31, 2019, 11:35:26 AM »
Tom, it is "conservation of energy". Matter consists of energy (and not the other way around).

Cassandrists, Malthusians and Luddites are ten a penny at all times and in all societies. We humans seem to have an inbuilt liking for predictions of doom - nobody became famous for saying that it's all going to work out fine, in fact, those who dare voicing any degree of optimism for the future of our species seem to become automatically vilified.

And when it turns out that the world didn't end, you write a book about why not, and find that you made a small error, and the end of the world is next year .. or perhaps the following year ...  So reading a 20 year old book about why predictions made 50 years ago have not become true yet (but will, definitely, within the next 5 years!) is not really my idea of a productive time.

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It may be different limits than climate change.
Pretend civilization arose in the Ediacaran https://en.wikipedia.org/wiki/Ediacaran
CO2 would start out at 4500 ppm. Our 2019 CO2e would be about 4720...about 5% higher.
Assuming ECS of 3˚ C then the change in temperature would be about 1/16 of 3˚ or about 0.2˚ C...quite survivable. We could put twice as much ∆CO2e and only raise it another 0.2˚. By then we would have depleted recoverable fossil fuel.

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Does the fact that we have not yet found intelligent life in the universe imply that many such past alien civilizations overshot their sustainability limit?

Title: "Are We Alone? Maybe. The Better Question Is, Can We Survive?"

https://www.nationalgeographic.com/science/2018/07/are-we-alone-in-the-universe--maybe--the-better-question-is--can/

Extract: "Whether we're alone in the universe depends on whether alien societies overcame the climate change their advances created, says a new book.

How bad does the probability of forming a civilization on a random planet have to be for us to be alone, for us to be the only time in the entire history of the universe that there’s ever been a civilization? That number is 1 in 10 billion trillion.

That number tells me that the only way that we can be the only civilization in cosmic history is if the odds are that low or lower. As long as there’s a probability larger than that, then it has happened before. So unless nature is really perversely biased against forming civilizations then there have been others.

Whether there are others in existence today, I cannot answer. It all depends on this important factor in the Drake Equation, the average lifetime of a civilization. You could have planets creating civilizations all the time, but if nobody makes it to more than, say, 200 years, then right now we would be living in a sterile galaxy. We can say that, yes, there have probably overwhelmingly been civilizations before us. The next step is, does anybody last long, particularly when climate change is going to be a natural consequence of civilization-building?"

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Arctic sea ice / Re: 2019 sea ice area and extent data
« on: December 11, 2019, 07:25:16 PM »

Barents - will above average sea ice area continue?


Barents: I'm curious as to why we started seeing encroachment onto the Shelf. for a few years there was little ice on the shelf because of (presumably) Atlantic water effectively melting ice as it crossed the continental shelf before flowing down the slope. Why is less warm water (or more cold water) finding its way to the shelf boundary and increasing extent? Has the AMOC slowed?; Is the warm water deeper; is it finding its way around to the Nares? Should I post this on stupid questions?

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Science / Re: 2019 CO2 emissions
« on: December 09, 2019, 02:52:34 PM »
Staying at or below 1.5°C requires reducing global greenhouse gas emissions  to 45 percent below 2010 levels by 2030

In 2010 CO2 emissions from fossil fuels & industry were circa 33 GT + **land-use changes 5 GT = 38 GT
In 2018 CO2 emissions from fossil fuels & industry were circa 37 GT + **land-use changes 5 GT = 42 GT

(**assumes no change)

So how are we doing in 2019? I sent an e-mail to ENERDATA.com
I got an answer. 2019 emissions from energy estimated to rise by 1 to 1.5% in 2019.
The main conclusion for me is that the drop in CO2 emissions from the reduction in coal + increase in energy from renewable sources is less than the increase in CO2 emissions from growth in Natural Gas and oil.

So assume
In 2019 CO2 emissions from fossil fuels & industry were circa 37.5 GT + **land-use changes 5 GT = 42.5 GT

For total CO2 emissions to reduce by 45% by 2030,
- 2030 total emissions down to 21 GT,
- 2030 emissions from fossil fuels & industry 16 GT (assumes no change in land-use changes)

That is a reduction of 58% in CO2 from fossil fuels & industry from 2019 to 2030..

It also assumes that emissions from land-use changes will not increase and the carbon sinks will not deteriorate.

Meanwhile..
Climate change: UN negotiators 'playing politics' amid global crisis
https://www.bbc.co.uk/news/science-environment-50706236

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Arctic sea ice / Re: 2019 sea ice area and extent data
« on: December 08, 2019, 11:40:00 AM »
JAXA ARCTIC SEA ICE EXTENT :- 10,805,648 km2(December 7, 2019)

A fourth day of extreme extent gains.

- Extent gain on this day 153 k, 99k more than the average gain of 54k,
- Extent gain in this freezing season to date is 6,841 k, 335k (5.2%) MORE than the average gain to date of 6,506 k.
- Extent is 4th lowest in the satellite record,
- Extent is 628 k more than 2016

- Extent is 7 k more than 2018
- Extent is 85 k (0.8%)  less than the 2010's average.

- on average 66.1 % of extent gain for the the season done, 95 days on average to maximum.

Projections.

Average remaining extent gain in the last 10 years from this date produces a maximum of 14.14 million km2, above the lowest in the satellite record by 0.26 million km2.
____________________________________________________________
Ice Gain Outlook??

Diminishing +ve SST anomalies.

GFS says Arctic temperature anomalies in the range +1.3  to +2.5 celsius over the next 5 days. However, these +ve temperature anomalies appear to have no effect on sea ice gains.

Winds still highly variable in strength and direction- especially at the Pacific Gateway and Atlantic Front, which are probably contributing to the recent large and even extreme extent gains.
_____________________________________________________________

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Arctic sea ice / Re: 2019 sea ice area and extent data
« on: November 24, 2019, 03:41:55 PM »
You're welcome, gerontocrat.
I have had some brain farts posting online myself, a few of them even more embarrassing.

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Arctic sea ice / Re: 2019 sea ice area and extent data
« on: November 24, 2019, 03:35:47 PM »
gerontocrat:
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Extent gain on this day 78 k, 26 k more than the average gain of 104 k
Don't you mean less than?

Thanks Tom, left my brain in the car park today.

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Antarctica / Re: Sea Ice Extent around Antarctica
« on: November 23, 2019, 07:42:43 PM »
It seems obvious now that 2019 will not follow that extraordinary year 2016, but does closely follow 2017 and 2018.

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Antarctica / Re: Where is D-26 headed?
« on: November 17, 2019, 08:03:56 AM »
Big oopsie.

This iceberg is called D-28, not D-26.

And also, it's stuck.

50
Arctic sea ice / Re: The 2019/2020 freezing season
« on: November 16, 2019, 10:45:08 PM »
Big spike up on the dmi north of 80 graph!

lol damn you weren't kidding


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