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Messages - kassy

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1
the Us and Europe still talk like they should be aplauded for getting to net zerro by 2050. we need a ban on new ff infrastructure ice vehicles today. net zero by 2030 or 2035 should be our goal.

Trying to make sense of this. Did you mean "applauded for talking about getting to net zero by 2050"?

Talk is cheap. Anyone looking at the chart for global emissions knows there is a snowball's chance in hell of getting to zero emissions by 2050.

No nation is doing what is needed. I hold out little hope of achieving this absolutely crucial goal.

2
The forum / Re: Arctic Sea Ice Forum Humor
« on: January 19, 2021, 04:50:51 PM »
Not sure if this counts as humor

3
Consequences / Re: COVID-19
« on: January 19, 2021, 03:20:10 PM »
Another New Covid-19 Variant Discovered In L.A. May Be Vaccine Resistant
https://deadline.com/2021/01/another-new-covid-19-variant-in-l-a-vaccine-resistant-denmark-1234675834/amp/
 
https://www.cell.com/cell/pdf/S0092-8674%2820%2930877-1.pdf

An article on Cell.com says L452R has “decreased sensitivity to neutralizing mAbs (monoclonal antibodies),” which are used in the currently-approved vaccines to inhibit connections between the spike proteins of the virus and infected cells.

Chiu said very early studies of the L452R spike protein mutation indicate it’s less susceptible to those neutralizing antibodies in the vaccines.

The article in Cell looks good to me.  The synopsis in deadline.com is dreadful.  The study in Cell did not examine vaccines, nor antibodies produced in response to vaccines.  Vaccines do not contain antibodies.  Nothing in the article directly addresses whether any variant of the virus is more or less likely to be inhibited by any vaccine.

The study did use convalescent serum from 10 recovering individuals.  Various strains showed modest increased or decreased inhibition by the various serum specimens.  There's not much here of particular note for us.

The journalistic drive to produce clickbait strikes again.

4
Consequences / Re: Global Surface Air Temperatures
« on: January 18, 2021, 10:02:16 AM »
Quote
Might we call another global warming hiatus?

You could.
But you would just be confirming  you are a scientifically illiterate denier of reality .

For those of us with some idea .
Interesting new post on real climate looking at the last years global temperatures including the influence  of  ENSO
   http://www.realclimate.org/index.php/archives/2021/01/2020-hindsight/

5
The forum / Re: Forum Decorum
« on: January 15, 2021, 11:07:12 AM »
Life here is so much better when you stick to the Cryosphere subsection.

Even reading this thread feels kinda like when I take a look at American news, as a Canadian.  :o ;D

6
Science / Re: Trends in atmospheric CH4
« on: January 12, 2021, 10:24:24 PM »
Almost a week later than usual an update of global CH4 is available from NOAA:

September 2020:     1884.0 ppb
September 2019:     1870.7 ppb
Last updated: January 05, 2021

This is an annual increase of 13.3 ppb. This is the third highest annual increase since February 2015 and way above the 10 y average increase of 7.78 ppb/a.

I set an index = 100 for the 1980 average [1601.2 ppb]. September 2020 is at 117.7 compared to that index.

7
Policy and solutions / Re: Coal
« on: January 11, 2021, 07:40:39 PM »
At one point in the last decade, there were six planned coal export terminals on the US west coast.  None of them have been built.  Five of the six have already been cancelled.  The sixth one was cancelled last week.

https://www.ft.com/content/1e4890c9-8ef1-41f6-a057-a92f9ae5fcb1

Quote
US coalminers’ Asia ‘pipe dream’ evaporates
Collapse of west coast port project deals blow to hopes of an export-driven recovery
Gregory Meyer 1/11/21


   Please use the sharing tools found via the share button at the top or side of articles. Copying articles to share with others is a breach of FT.com T&Cs and Copyright Policy. Email licensing@ft.com to buy additional rights. Subscribers may share up to 10 or 20 articles per month using the gift article service. More information can be found at https://www.ft.com/tour.
   https://www.ft.com/content/1e4890c9-8ef1-41f6-a057-a92f9ae5fcb1

   US coal miners’ last-ditch hope for shipping big volumes to Asia has crumbled as the developer of a sprawling export terminal abandons its project on the Pacific coast.

The Millennium Bulk Terminal would have loaded 44m metric tonnes a year of thermal coal for export to electric utilities — a potential boost for producers reeling from the decline of coal-fired power generation in the US.

But the project’s bankrupt owner on Saturday pulled the plug, making it the last of more than half a dozen proposed west coast coal ports never to be built. “It’s the end of the pipe dream that Asia can save the US coal industry,” said Clark Williams-Derry, analyst at the Institute for Energy Economics and Financial Analysis, a research group that favours clean energy.



Quote
The Millennium project’s current owner, the mining company Lighthouse Resources, filed for bankruptcy protection in December. The company on Saturday relinquished the site to land owner Northwest Alloys, a subsidiary of the aluminium maker Alcoa. Alcoa said it would evaluate plans for the location, making no mention of coal.

8
Consequences / Re: Origins of COVID-19
« on: January 09, 2021, 05:09:00 PM »
I don't really care what the origin of SARS-CoV-2 is, because all possibilities point to the same culprit: the need to grow and further concentrate concentrated wealth. The main reason I'm even posting in this thread, is that it annoys me that any and every proposed alternative is swept off the table using the propagandist term 'conspiracy theory'. As with many things surrounding the SARS-CoV-2 narrative, it's what has been said early on that remains stuck, that then gets repeated and becomes part of this circular reasoning process. For some reason or other, people have this need to automatically defend it all over the Internet and social media. It's a craving for some agreed upon reality, because the alternative - disorder, chaos - is apparently too frightening to consider. But an agreed upon reality rarely coincides with reality itself, and only leads to even more chaos in the long term.

That's why I like to look at the whole picture and let that shape my opinions. In this case, I don't care whether the thing came from bat soup, pangolins eating bird shit at a wet market, a Chinese lab assistant picking his nose or the CIA releasing it during the police olympics. As said, whatever the origin is, the reason for it coming about is the same in all instances (either directly indirectly). It's also the reason the virus spread so successfully around the globe, why it was able to cause such an impact in degenerated populations, and why the reaction is so manipulated and misguided.

People should be able to discuss this and not get shouted down because some Trump idiot supporter or whoever talks in seemingly similar terms.

Anyway, I thought this guy was pretty much accepted here and he talks a bit about the origin of SARS-CoV-2:


9
Walking the walk / Re: Gardening
« on: January 09, 2021, 10:10:46 AM »
I do not remember if this article has been quoted before in this thread:

https://www.shelterwoodforestfarm.com/blog/the-lost-forest-gardens-of-europe

This is a truly interesting article (with scientific research quoted), detailing how late stone age Europeans relied very much on semi-wild/semi-cultivated hazel groves for a significant portion of their diet and how climate changed destroyed these ancient, sustainable forest gardens, leading our ancestors to (unsustainable) grain production and working only a few hours a day to toiling all day.

I more and more believe that our whole agricultural system is based on the phallacy of annuals while truly sustainable systems are almost always tree-based / agroforestry systems with mostly perennial produce (various nuts, eg. hazel, chestnut, pecan, walnut etc and fruits) and some annual vegetables in between (and possibly small animals raised in theses groves).

However, as our diet is very much based on grains, we would also have to change our dietary habits, which is a very hard sell...

10
Arctic sea ice / Re: The 2020/2021 freezing season
« on: January 08, 2021, 04:03:45 PM »
A rebound is a change in direction. To most that implies a sustained change. While their is not a precise definition in this case that would be a major increase in ice.  A minor uptick does not qualify. Their is a well established trend of decreasing ice with some yearly variation. Minor variations are not a rebound to most people even if your views are different.

11
Arctic sea ice / Re: What's new in the Arctic ?
« on: January 07, 2021, 04:10:53 PM »
The end-game begins through the Nares Strait?

"Ice arches holding Arctic's 'last ice area' in place are at risk, researcher says"
https://phys.org/news/2021-01-ice-arches-arctic-area.html

Excerpts  -------
But recent research at the University of Toronto Mississauga suggests the last ice area may be in more peril than previously thought. In a recent paper published in the journal Nature Communications, Professor Kent Moore and his co-authors describe how this multi-year ice is at risk not just of melting in place, but of floating southward into warmer regions. This, in turn, would create an "ice deficit" and hasten the disappearance of the last ice area.

"The last ice area is losing ice mass at twice the rate of the entire Arctic," Moore says. "We realized this area may not be as stable as people think."

His most recent analysis of satellite data says the problem may be getting even worse. The arches along Nares Strait that historically have held the Last ice Area in place have become less stable, according to the study.

"The ice arches that usually develop at the northern and southern ends of Nares Strait play an important role in modulating the export of Arctic Ocean multi-year sea ice," he and his authors write.

Ice arches only form for part of the year. When they break up in the spring, ice moves more freely down the Nares Strait. And that breakup is happening sooner than in the past.

"Every year, the reduction in duration is about one week," (emphasis added by GK) Moore says. "They used to persist for about 200 days and now they're persisting for about 150 days. There's quite a remarkable reduction.

"We think that it's related to the fact the ice is just thinner and thinner ice is less stable."

More information: G. W. K. Moore et al. Anomalous collapses of Nares Strait ice arches leads to enhanced export of Arctic sea ice, Nature Communications (2021). DOI: 10.1038/s41467-020-20314-w

12
The politics / Re: The Trump Presidency
« on: January 07, 2021, 02:09:47 AM »

13
Arctic sea ice / Re: What the Buoys are telling
« on: January 05, 2021, 12:46:37 PM »
drift track and ~6m-200m temperature and salinity profile contours for selected whoi itp's. The criteria for selection was that the buoys should drift close to or within the BGOS buoy moorings (white circles) and have a reasonably long profile. Some fail quickly. Note that there are a couple of scale changes early on and that often the drift track is longer than the profiler battery life (or other reason for failure). So, as nearly always, this is just a very rough historical guide over a small area in the Beaufort from 2006-2021
White can often be interpreted as warmer than top of the scale (off the chart) but may also be due to missing data. For itp121 white means off the chart. Found a newer version of itp5 temp.

14
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: January 03, 2021, 07:16:01 PM »
Interesting data.

I take it that the three years cited above are the top 3. Could you add a table (or graph) of the other years?
Is there some confusion here  ?
The graph above is not the 365 day trailing average.
It is the simple average of daily extent for each year.

Perhaps the attached column graph makes it more obvious.

15
Arctic sea ice / Re: 2021 Sea ice area and extent data
« on: January 03, 2021, 04:37:25 PM »
Hi Gero.

I think that these numbers need to be changed to 2021...

NSIDC Total AREA as at 02-Jan-2021 (5 day trailing average) 11,070,767 KM2         
         
Sea ice area gain on this day 17 k, 32 k less than the 2010's average gain of 49 k         
         
- 2020 2021 area is at position #2 in the satellite record.         
- 2020 2021 ...         
         
NSIDC Sea ice EXTENT gain on this day 26 k, 24 k less than the 2010's average gain of 50k         
         
- 2020 2021 EXTENT is at position #4 in the satellite record.         
- 2020 2021 ...   

P.S. People that do nothing, they do not make mistakes. Thank you for all the work that you do!
And thanks to everyone that participates! We have the best internet Arctic sea ice forum here!

Happy new year!   ;)

16
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: January 03, 2021, 12:29:43 PM »
JAXA Data - a bit more on 2020

2020 had the lowest average daily sesa ice extent in the satellite record.

The simple daily average daily sea ice extent for the year was 9.674 million km2.
This was 42k less than in 2016, and 285k less than in 2012.

Put in another way, in 2020 there was on average 42k less ice and 42 k more open water for every day of the year than in any other year.

17
Arctic sea ice / Re: What the Buoys are telling
« on: December 30, 2020, 07:39:00 PM »
Definitely looks like it depends on the year (and where the buoys are)

18
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: December 30, 2020, 04:15:12 PM »
NSIDC Data Query

Not a lot of people know that the NSIDC sea ice extent total is greater than the sum of extents of the 14 seas.....

I wrote to NSIDC this...
______________________________________
Every day I download the 5-day Arctic Sea Ice trailing averages for the 14 regions from N_Sea_Ice_Index_Regional_Daily_Data_G02135_v3.0.xlsx and post an analysis on the Arctic Sea Ice Forum. That analysis includes adding up the total sea ice extent of the 14 seas.

But that total does not agree with the 5-day trailing average extent from
file Sea_Ice_Index_Daily_Extent_G02135_v3.0.xlsx

The value from this file is always about 100k km2 greater than the figure
from adding up the 14 individual Arctic regions. See table below

Is this just because its how the algorithms work?
Which figure for the total should I use ?

              Total of
              the 14 seas
              5-day extent      NSIDC 5 day extent   Difference
21-Dec     12.118                    12.216                   0.098
22-Dec     12.220                    12.326                   0.106
23-Dec     12.297                    12.401                   0.104
24-Dec     12.346                    12.451                   0.105
25-Dec     12.390                    12.494                   0.104
__________________________________________

And got a reply from the man himself (Walter Meier)
____________________________________________
"The total is the entire polar stereo grid. If one looks at the regions, there are areas of the grid outside of these regions. Most, if not all of such ice is false ice - i.e., either weather effects or land-spillover error. However, there can be some legitimate ice - mostly this would be in winter in places like the Bohai Sea off the coast of China or in the Chesapeake Bay (though this is brackish water, so one could argue if that is “true” sea ice). The area of such extraneous ice is, as noted in the data, quite small: ~100,000 sq km."
_______________________________________

19
Arctic sea ice / Re: The 2020/2021 freezing season
« on: December 30, 2020, 04:08:19 PM »
Quote
ice is always melting along much of the West Spitzbergen current. During most winters drift speed and thickness is enough that it is not visible from above
Right. OsiSaf quantitates ice displacements. Smos-Smap is in its element for sub-half meter ice thinness, showing Barents ice growth, shelf melt, and lee polynyas; pairing with AMSR2_UHH_3.125 concentration above might help disentangle these. Cryo2Smos has sub-optimal resolution but does ok. The effect of waves on the Barents MIZ ice has been the focus of a  neXtSIM improvement project, not yet in the CMEMS product.

https://www.researchgate.net/publication/338803774_Wave-sea-ice_interactions_in_a_brittle_rheological_framework 2020
https://tc.copernicus.org/articles/11/2117/2017/tc-11-2117-2017.pdf 2017

Wrapping the 'white band' discussion, a later Sentinel-1B extending farther east appears to show a series of three wave-deposited layers of MIZ onto SYI as the source; these ice fragments may be too fractured to retain brine pockets and so, lacking dielectric, effectively reflect Ascat's radar.

20
Antarctica / Re: Antarctic Icebergs
« on: December 30, 2020, 03:54:16 PM »
A-68-A

There are apparently some biologists out there who are concerned; they probably know something.
Or they want to generate publicity to get more funding.
Funding they have - British Antarctic Survey supposed to be on their way early January. Knowing their luck with this berg it will either be in little pieces and /or have been swept away from the South Georgia shallows by the time they get there.

ps: I wrote to Leeds Uni about whether we would see more data. Prof Shepherd responded

Quote
Hi Matt

Thanks for getting in touch, and I’m glad you found our data interesting!

It really is our first estimate of thickness change and we released the high-level information because there is a team headed down to study the berg and it will be of use to them. But we have not had chance to write the analysis up yet, and until we do that the numbers should be considered preliminary. I don’t expect them to change much, but we still need to run over the analysis with a fine tooth comb and you never know until that is done.

I tend to agree with some of the comments on your post that it is hard to compare sea ice and icebergs as they are quite different geometries; icebergs fragment at their sides far more than sea ice does as they have relatively high walls that develop greater stresses which can cause the ice to fracture. Plus their keels are much deeper in the ocean and so they encounter different (often warmer) temperatures too – especially in winter.

We put in quite a lot of effort over these past few weeks to get the analysis to the present stage, and the team have taken a break since then so I’m afraid there isn’t an update yet. If the berg is still large enough for us to track with altimetry when they get back I am sure we will post an update, but as it breaks up our chances of spotting it diminish I’m afraid so we may not get another look. Fingers crossed!

Andy

21
Arctic sea ice / Re: The 2020/2021 freezing season
« on: December 30, 2020, 01:17:46 PM »
-- Was this ice retreat wind-driven?  If so, then it indicates to me the ice front in that area was really fragmentary and weak in its nature in mid December. <>
Yes. There are similarities with 2016. Note the refreeze south of the wind driven ice front (see #953 above)
Is it melting? In my view ice is always melting along much of the West Spitzbergen current. During most winters drift speed and thickness is enough that it is not visible from above except (imo) occasionally along the shelf break north of FJL.

amsr2-uhh comparison of 2020 and 2016, dec20-29

22
Science / Re: Satellite News
« on: December 29, 2020, 05:00:02 PM »
... got to love that Japanese joinery ...

Japanese Looking Into Using Wood to Build Satellites
https://techxplore.com/news/2020-12-japanese-pairing-wood-satellites.html

Japanese company Sumitomo Forestry has announced a joint development project with Kyoto University to test the idea of using wood as a component in satellite construction.

Some of the major components in most satellites include aluminum, Kevlar and aluminum alloys, which are able to withstand both temperature extremes and constant bombardment by radiation—all in a vacuum. Unfortunately, these characteristics also allow satellites to remain in orbit long after their usefulness has ended, resulting in constant additions to the space junk orbiting the planet.

There are currently approximately 6,000 satellites circling the Earth but only 60% of them are still in use. Some in the field have predicted that nearly 1,000 satellites will be launched into space each year over the coming decade. Considering their lifespan, this suggests there could be thousands more dead satellites orbiting the planet in the coming years. This space debris poses a significant threat to other satellites (they all travel thousands of miles per hour) and also to manned space missions.

And there is more bad news—the aluminum used in satellites has been found to break apart when a satellite returns to Earth, creating hundreds or thousands of tiny alumina particles that wind up floating in the upper atmosphere for many years, possibly posing an environmental problem. For all these reasons, the researchers with this new project are looking to replace these materials with wood.

The major benefit of wood-based satellites is they would burn up completely when returning to Earth. But another major bonus of using wood to create the outer shell of a satellite is that electromagnetic waves would pass right through it, which means antennas could be placed inside of satellite structures, making them simpler to design and deploy. The researchers plan to look for appropriate wood candidates and then to conduct experiments to see it they could be treated to stand up to space conditions. They predict they will have a product ready for testing by 2023.

--------------------------------------------

... I've got some old cigar boxes if they need them...

23
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: December 29, 2020, 02:59:46 PM »
Graphs from NSIDC Data - The Atlantic Front.

While the Kara Sea extent and area rush to completion, the Barents, Greenland and central Arctic do not.

Indeed, the Central Arctic has lost 150k sea ice area over the last 5 days. This is an impressive push back of the sea ice back North of 80 along a realtively short front between NE Greenland and Svalbard.


24
Antarctica / Re: Sea Ice Extent around Antarctica
« on: December 27, 2020, 03:56:06 PM »
I was concerned (reply 1595, December 13) that the concentration graph might be warning that high melt might be approaching - I am wondering what that graph is now saying in comparison with previous years    .    .    . (if concentration is still relatively low it may indicate that high melt could continue).
Concentration graphs attached

25
Antarctica / Re: Pine Island Glacier (PIG) Calving and Discussion
« on: December 27, 2020, 01:13:18 PM »
Small emptying of the NdDZ ( Northern downstream Damage Zone)
Animation with the two images (low resolution) of yesterday and today.

26
Antarctica / Re: Antarctic Icebergs
« on: December 27, 2020, 11:39:10 AM »
The 2020 title in the category long distance goes to B09I with an impressive 3711km travelled. A true champion indeed. Far behind in second place comes A68C with 2471km. Close behind comes D21B snatching third place from A68A. All candidates that traveled over 250km this year can be seen in the picture below.

Edit: Here is the full list

Iceberg Kilometer
B09I   3712
A68C   2471
D21B   2445
A68A   2319
B39   1642
C34   1439
D28   1184
A63   912
C33   904
C18B   846
A68B   727
B16   720
B15AA   686
B50   444
B43   347
B46   333
B48   317
A69B   243
A69A   240
B37   187
D27   180
B49   164
D26   137
B42   131
A23A   129
A68D   55
B47   52
B09B   48
B40   33
D15A   31
C29   30
A64   26
C15   20
B38   19
D20A   17
B22A   16
B09G   13
C35   10
B29   6
A69   4
D23   4
B15AB   4
D15B   3
B28   3
B45   2
C36   2

27
The forum / Re: Merry Christmas everyone.
« on: December 26, 2020, 02:59:51 AM »
Our Christmas was different:  We cooked for each other (2 of our kids, separately, and us) and exchanged containers for eating later.  A pair and a trio (including partners) visited for 1/2 hour spells, all always masked (one set with a porch screen between us and jackets on).  It felt Christmasy as we had a slight frost this morning (2/10 of a degree F!), colder tonight.

I remember my 1972 Christmas in Sydney.  They were having a hot spell (40C).  Bondi Beach was beautiful, but the sand was too hot to stand on and a shark kept us on the shore...  Christmas dinner (made by Aussies) was 'everything we were used to, only cold'.

One Christmas in NZ I hitch hiked from Dunedin northwards.  I hoped to get to Christchurch, but went way further.  Lots of mostly short rides (14, IIRC) and seldom even 5 minutes between them. Nobody, it seemed, wanted to leave a stranger on the road. The first ride was from a nurse taking presents to patients at the mental health hospital just north of town and the last was with a family coming from Dinner (capital "D") with the wife's family and headed for Dinner with the husband's.  That man sure did talk, and he described every dish they'd had and the specialties he was looking forward to.  (Wife and 2 kids were silent.)  I never told anybody that day that I was fasting; it was easy to be with my hosts in their various styles of joy and thanksgiving.  It was a truly blessed day for me!  It ended 'early' as I was left off at a totally rural highway intersection, and I decided to stop.  Beside the road was a copse of trees in which I camped, and a large stream/small river, cobble-bedded.  I meditated in the stream (seated, with water up to my mid-chest) for an hour or so, during that sunny endless summer evening.

I know, it's Boxing Day now for most of you!

Find (and share) the blessings,
Tor

28
Arctic sea ice / Re: The 2020/2021 freezing season
« on: December 25, 2020, 12:46:43 AM »
The mp4 below shows 84 days of the fall freeze season, from Oct 01 to Dec 23. Here SMOS was used at 132.24% enlargement to provide masks for land, open water and thin ice as Ascat alone has distracting artifacts there especially early in the season.

Note a white band of ice (an extended virtual buoy for tracking purposes) forms early on in the northern Laptev at the FYI/SYI edge (as it did last year) and will likely remain trackable until May. The overall pattern of ice movement here has been a squash towards Greenland and the CAA.

The physical explanation for the hundreds of km of white band remains elusive. Efficient scattering from low dielectric near-surface ice is typically seen in older ice that has lost its brine pockets. However Ascat's active microwave beam can also be reflected back from crumpled ice with right-sized debris particles. How and why this would form at the edge of SYI perhaps may require strong 'offshore' winds piling up newly formed ice. The area is inaccessible to ships and the feature may not be apparent at visible or infrared wavelengths anyway.

Other stably advecting Ascat features such the large dark elongated patch in the north Beaufort also lack interpretation. This area froze up very rapidly in patches per Smos-Smap and so may have incorporated extra near-surface salinity which would indeed make it appear darker.

Note too the unusual mid-December surge of ice west across the Chukchi to the shores of Chukotka; usually western Alaskan ice originating northeast of Banks Island turns north upon reaching the eastern Chukchi, perhaps riding Bering Strait inflows.

This can be attributed to the persistent anti-cyclone over the period 08-24 Dec 2020 that has brought clear skies and with it excellent Suomi band 15 views of heat loss from leads and their motion (https://go.nasa.gov/2KPeWlH opens to a good palette set-up). As the large diameter anti-cyclone wandered across the Arctic Ocean towards the Kara side, winds often blew in the opposite direction of that needed for a return Gyre.

Export out the Fram has picked up but has the odd oblique meridional surge is from the central CAB rather than the usual zonal route between the pole and the SZ-FJL-Svalbard. This could have the effect of exporting older thicker ice but this year, as witnessed by the Polarstern, the ice between Greenland and the pole did not fit that description in September.

29
The politics / Re: Midterm American elections 2022
« on: December 23, 2020, 06:24:52 PM »
A google seach leads to a Wikipedia article that answers your question.  Try it and post your answer.

30
Antarctica / Re: Antarctic Icebergs
« on: December 22, 2020, 02:33:35 PM »
It's broken
It happened between the 21/12 22h42 and the 22/12 07h17.
Attached two versions of the animation:
> the first one very small
> and the second one slightly reduced (to animate it you have to click on it and to enlarge it click again).

31
Consequences / Re: Global Surface Air Temperatures
« on: December 22, 2020, 12:15:40 AM »
Threshold for Dangerous Climate Warming Will Likely Be Crossed Between 2027–2042
https://phys.org/news/2020-12-threshold-dangerous-climate.html

The threshold for dangerous global warming will likely be crossed between 2027 and 2042—a much narrower window than the Intergovernmental Panel on Climate Change's estimate of between now and 2052. In a study published in Climate Dynamics, researchers from McGill University introduce a new and more precise way to project the Earth's temperature. Based on historical data, it considerably reduces uncertainties compared to previous approaches.

... Until now, wide ranges in overall temperature projections have made it difficult to pinpoint outcomes in different mitigation scenarios. For instance, if atmospheric CO2 concentrations are doubled, the General Circulation Models (GCMs) used by the Intergovernmental Panel on Climate Change (IPCC), predict a very likely global average temperature increase between 1.9 and 4.5C—a vast range covering moderate climate changes on the lower end, and catastrophic ones on the other.

"Our new approach to projecting the Earth's temperature is based on historical climate data, rather than the theoretical relationships that are imperfectly captured by the GCMs. Our approach allows climate sensitivity and its uncertainty to be estimated from direct observations with few assumptions," says co-author Raphael Hebert, a former graduate researcher at McGill University, now working at the Alfred-Wegener-Institut in Potsdam, Germany.

In a study for Climate Dynamics, the researchers introduced the new Scaling Climate Response Function (SCRF) model to project the Earth's temperature to 2100. Grounded on historical data, it reduces prediction uncertainties by about half, compared to the approach currently used by the IPCC. In analyzing the results, the researchers found that the threshold for dangerous warming (+1.5C) will likely be crossed between 2027 and 2042. This is a much narrower window than GCMs estimates of between now and 2052. On average, the researchers also found that expected warming was a little lower, by about 10 to 15 percent. They also found, however, that the "very likely warming ranges" of the SCRF were within those of the GCMs, giving the latter support.

Raphaël Hébert et al, An observation-based scaling model for climate sensitivity estimates and global projections to 2100, Climate Dynamics (2020)
https://link.springer.com/article/10.1007/s00382-020-05521-x

Abstract: ... Projecting to 2100, we find that to keep the warming below 1.5 K, future emissions must undergo cuts similar to RCP 2.6 for which the probability to remain under 1.5 K is 48 %. RCP 4.5 and RCP 8.5-like futures overshoot with very high probability

32
Consequences / Re: COVID-19
« on: December 21, 2020, 04:23:24 PM »
Rodius did not just make the statement about higher viral loads up, it is a direct quotation from SH's post #10316 about South Africa:

"The South African variant appears to be spreading more quickly, with higher viral loads than the original virus."

https://www.ecdc.europa.eu/sites/default/files/documents/SARS-CoV-2-variant-multiple-spike-protein-mutations-United-Kingdom.pdf

They found that the new variant has often lower ct (cycle threshold) values, so higher concentrations. My guess is about 2 x 2 = 4.

Quote
  • PCR ct values: which suggest a decrease of ct value of around 2 associated with
    the new variant.
  • Viral load inferred from number of unique genome reads: which suggests 0.5
    increase in median log10 inferred viral load in Y501 versus N501.

And 0.5 in log10 would be a factor of 3.

33
Consequences / Re: COVID-19
« on: December 21, 2020, 03:06:06 PM »
kassy, harpy

Viral load, also known as viral burden, viral titre or viral titer, is a numerical expression of the quantity of virus in a given volume of fluid.

copies/mL - milliliter (milliltre) for those who can't spell  :P

That can be any fluid: blood, urine, sputum, water, sewage, etc.

The numbers may be different in blood or nasal mucus because of viral distribution, but the term 'viral load' is used in both.

If you want a reference ... I worked in clinical labs for 40 years ... This is basic knowledge.

34
Consequences / Re: Forests: An Endangered Resource
« on: December 18, 2020, 11:12:35 PM »
Some Tropical Forests in Brazil Are Already Releasing More Carbon Than They Absorb
https://earther.gizmodo.com/some-tropical-forests-in-brazil-are-already-releasing-m-1845914059

For years, climate scientists have been sounding the alarm about the increasing likelihood that the Amazon rainforest, now one of the biggest absorbers of carbon in the world, could actually become a source of carbon within just 15 years. New research shows that for some other kinds of tropical forests nearby, that’s already happening.

That’s due in large part to intentional forest burning. In South America, mining, cattle ranching, and soybean farming industries frequently set trees ablaze to make room for their operations, turning forests into open pastures.

That means forests contain less foliage to suck greenhouse gas out of the atmosphere. To make matters worse, when a tree catches fire, it releases all the carbon it sequestered in its lifetime, meaning the forests become a source of planet-warming emissions. And amid the climate crisis, this problem is even more severe, because amid hotter and drier conditions, the forests don’t produce enough humidity to quickly put out the flames, meaning more area burns with less effort.

A new study, published in Science Advances on Friday, aimed to see how South American forests’ carbon intake has changed in recent years. To do so, the authors analyzed greenhouse gas monitoring data from 1987 to 2020 on 32 deciduous, semi-deciduous, and evergreen forests—each of which has seen deforestation—in the lush state of Minas Gerais in southeastern Brazil. Altogether, the area they examined spanned some 81.5 acres (33 hectares).

By plugging this data into statistical models, the authors found that on average, these forests are now sucking up 2.6% less carbon per year than they were 33 years ago. At the same time, the forests’ carbon output from fires increased by 3.4% per year, meaning overall, they’re losing their ability to absorb the gas. These changes were enough to push the forests over the edge from carbon sinks to carbon sources. The authors fear their findings may be able to be extrapolated to tropical forests in the region as a whole.

The data shows that the switch happened in 2013. That year, on average, the examined forests released 0.14 U.S. tons per 2.5 acres (0.13 metric tons of carbon per hectare), or the equivalent output of driving 323 miles in a diesel car.

The authors’ findings are particularly troubling because separate research recently found that the importance of tropical forests’ carbon sequestering is nearly as important as that of the Amazon rainforest.

Vinícius Andrade Maia, et.al, The carbon sink of tropical seasonal forests in southeastern Brazil can be under threat, Science Advances, (2020)
https://advances.sciencemag.org/lookup/doi/10.1126/sciadv.abd4548

35
Arctic sea ice / Re: MOSAiC news
« on: December 18, 2020, 03:45:24 PM »
Quote
gyre doesn't have to mean gyre
'I don't know what you mean by "gyre",' Alice said. Humpty Dumpty: 'Of course you don't — till I tell you. I meant 'there's a nice little drift for you!' 'But "gyre" doesn't mean "a nice little drift",' Alice objected, 'it's meant circular for several thousand years.'  'When I use a word,' Humpty Dumpty said, 'it means just what I choose it to mean — neither more nor less.'
Quote
I saw a partial full ice gyre once on an oblique low resolution 40-year youtube
A pity you didn't take note of the date. 
Quote
there's a distinction between an ocean gyre and an ice drift gyre.
Right. Many oceanographic writings avoid ice motion, or the lack of it, that we see in buoy tracks and satellite time series. They are talking about inferred deep water currents and a large pool of slightly reduced salinity (confusingly called "fresh water"). There is not a single drop of fresh water anywhere in or under the central Beaufort Sea. T

he 28-frame gif below collects some of the silliness surrounding 'Beaufort Gyre' depictions -- it's whatever and wherever you want it to be! Publishing garbage diagrams undermines public trust in overall climate science -- we cannot afford that.

https://sci-hub.se/https://doi.org/10.1029/2018JC014379 rare serious treatment
https://cpom.org.uk/glimpsing-under-the-ice-measuring-the-ice-covered-arctic-ocean-from-space/

OsiSaf/GFS have shown over and over that when the wind does not blow, the ice does not move. That means no surface currents of any significance (Nares, Fram, Yermak, FJL, Bering excepted). Ice motion in the central Arctic Ocean is entirely wind-driven.

That's a problem for the 'Beaufort Ice Gyre' because the 'Beaufort High' is rarely where it needs to be. Often the high is bounded on its south by land, causing strong winds up the Alaskan coast that make ice drift rapidly west there (before breaking apart melting out in the Chukchi as 'Big Block' did in 2016). The problem is the opposite side of the 'Beaufort High' is often elsewhere, failing to move the pack ice in a gyre (Fig.2).

The Polarstern measured currents, tides, turbulence and eddies under the ice during their long drift but has not released any data. The TransPolar Drift, while highly variable and largely unpredictable, is not as frothy a subject as non-existent Beaufort Ice Gyre but might better be called the CircumPolar Drift because  in the last decades, ice has rarely drifted over the north pole ('trans' means across) as it did during the Mosaic year.

CMEMS, our main online source for oceanographic time series, provides very detained views of Arctic Ocean ice motion from 01 Nov 2018 into late Dec 2020 with its daily neXtSIM product. At some point, that product will be extended much farther back in the satellite record (that's used for daily assimilations).

For now, it allows complete coverage of the Mosaic year, as well as regions elsewhere in the Arctic. However file size is an issue for the full 781 days, especially for the 2.1 GB gif. A small preliminary version of the western sea ice motion is attached below.

Although neXtSIM overlaps (ie extends) Polarstern 6-hourly bow radar scale, the latter is confined to its drift track. The current persistent high associated with the anti-cyclone has allowed an extraordinary and continuing basin-wide view of heat-leaking leads via Suomi Band 15 infrared.

The attached gif shows the full range of scale zooms for the available resolution. While ice fractures aren't really fractal in the mathematical sense, new leads become visible the larger the scale -- the Beaufort ice shown has had a surprisingly extensive history of fracture. These continue to leak heat more rapidly than their matrix until such time as the thicknesses more or less equalize.

36
The forum / Re: Forum Decorum
« on: December 18, 2020, 02:22:37 AM »
Navajo proverb: You can't wake someone up who is only pretending to be asleep

37
Policy and solutions / Re: Electric cars
« on: December 17, 2020, 09:04:38 PM »

Were you factoring in the change from Gas to heat pump HVAC heating?

But here is a slightly different view again.

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/928350/2020_Energy_Consumption_in_the_UK__ECUK_.pdf

UK electricity consumption is just over 25mtoe.
UK gas consumption is just under 45mtoe.
UK petroleum consumption is just over 60mtoe.

Tell me again just how we are going to get away with a 10% upgrade on the electricity grid?

Granted I'm with you to a degree with the fact that EV's are more efficient and we can schedule the charging.

BUT.

If you think for one second that we are going to get away with some second hand retread of our UK electricity grid, for carbon neutral in 2050, when 75% of our mtoe energy consumption is fossil based and only 25% is electricity or other, you are going to have to think again.we expect to be virtually full EV on the roads by 25 years from now.

Lets not scare ourselves by the inefficencies of fossil fuels or make false assumptions that everyone will be charging their car and running their heating all night.  Nor should we scaremonger that the grid is so past it that it needs a full replacement.

Our peak demand has fallen from 62GW to 46GW over the last 15 years so we know the it can handle a 10% increase to 51GW for EVs with very little stress.  Beyond this the maximum the grid can handle according to the National grid themselves is 80GW so this aging infrastructure aint too shabby.

Next we need to accept that the priority now based on government policy is the take up of EVs, they have scrapped the commitment to ban gas boilers for the forseeable so the rise in demand from heat pumps is not yet on the horizon.

Thirdly we should take on board the comments from Iain, Tor and Silkman regarding storage, insulation  and efficencies .
V2G and other smart grid technology will play a part
https://www.octopusev.com/powerloop

Finally I think the modelling done by the national grid tells us that they know what they are doing , they do not see us reaching the historic high demand from 15 years ago within the next 15 years even with an aggressive EV and home energy decarbonisation. 

So the idea we have to delay the roll out of EV chargers now for improvements to the grid that will be targetted at net zero by 2050 just doesnt add up.


On the EV front, I was speaking to our fleet manager today and they have stopped taking diesels and are replacing them with EVs.  Also a large number of employees who previously had a company car are handing them back and registering their second car for car allowance.  With the need to visit customers and offices reduced, many no longer see the need for them and their partner to have two cars.

38
Antarctica / Re: Antarctic Icebergs
« on: December 16, 2020, 11:14:12 PM »
For reference, I made a map showing how big A68a is in comparison to Europe.

39
The politics / Re: Brexit...
« on: December 16, 2020, 09:15:09 AM »
A long time ago I spent a few weeks in Union Hall, West Cork.
In the pub I was talking to a couple named "O'Sullivan".

But later this old guy said to me - "they are not real O'Sullivans". It seems that the family was known to have changed the family name to Sullivan when Ireland was under British rule, and changed it back some time after Eire was born. This name change also changed where to go to Church on Sunday and also one's economic prospects.

You may not be aware that the same sort of thing was in force in Mostar, Bosnia when under the Ottoman Empire. If you brought your goods to market in Mostar from the West i.e. from the Austrian/Hungarian Empire, you would be exempted from taxes if you named yourself with the Islamic vs the Christian form of your name.

Yup, that all sounds entirely plausible. And in West Cork, there are so many even in one town that an O'Sullivan generally has to be distinguished by their middle initial: so it's Michael J O'Sullivan, Michael T, Michael K, etc.

What a great forum. History, Culture AND Science...  :D

40
Arctic sea ice / Re: What's new in the Arctic ?
« on: December 15, 2020, 10:28:40 PM »
Oceanographers Find Explanation for the Arctic's Puzzling Ocean Turbulence
https://phys.org/news/2020-12-oceanographers-explanation-arctic-puzzling-ocean.html



Eddies are often seen as the weather of the ocean. Like large-scale circulations in the atmosphere, eddies swirl through the ocean as slow-moving sea cyclones, sweeping up nutrients and heat, and transporting them around the world.

In most oceans, eddies are observed at every depth and are stronger at the surface. But since the 1970s, researchers have observed a peculiar pattern in the Arctic: In the summer, Arctic eddies resemble their counterparts in other oceans, popping up throughout the water column. However, with the return of winter ice, Arctic waters go quiet, and eddies are nowhere to be found in the first 50 meters beneath the ice. Meanwhile, deeper layers continue to stir up eddies, unaffected by the abrupt change in shallower waters.

This seasonal turn in Arctic eddy activity has puzzled scientists for decades. Now an MIT team has an explanation. In a paper published today in the Journal of Physical Oceanography, the researchers show that the main ingredients for driving eddy behavior in the Arctic are ice friction and ocean stratification.

By modeling the physics of the ocean, they found that wintertime ice acts as a frictional brake, slowing surface waters and preventing them from speeding into turbulent eddies. This effect only goes so deep; between 50 and 300 meters deep, the researchers found, the ocean's salty, denser layers act to insulate water from frictional effects, allowing eddies to swirl year-round.

The results highlight a new connection between eddy activity, Arctic ice, and ocean stratification, that can now be factored into climate models to produce more accurate predictions of Arctic evolution with climate change.

"As the Arctic warms up, this dissipation mechanism for eddies, i.e. the presence of ice, will go away, because the ice won't be there in summer and will be more mobile in the winter," says John Marshall, professor of oceanography at MIT. "So what we expect to see moving into the future is an Arctic that is much more vigorously unstable, and that has implications for the large-scale dynamics of the Arctic system."



... Now that they have confirmed that ice friction and stratification have an effect on Arctic eddies, the researchers speculate that this relationship will have a large impact on shaping the Arctic in the next few decades. There have been other studies showing that summertime Arctic ice, already receding faster year by year, will completely disappear by the year 2050. With less ice, waters will be free to swirl up into eddies, at the surface and at depth. Increased eddy activity in the summer could bring in heat from other parts of the world, further warming the Arctic.

At the same time, the wintertime Arctic will be ice covered for the foreseeable future, notes Meneghello. Whether a warming Arctic will result in more ocean turbulence throughout the year or in a stronger variability over the seasons will depend on sea ice's strength.

Regardless, "if we move into a world where there is no ice at all in the summer and weaker ice during winter, the eddy activity will increase," Meneghello says. "That has important implications for things moving around in the water, like tracers and nutrients and heat, and feedback on the ice itself."

Genesis and decay of mesoscale baroclinic eddies in the seasonally ice-covered interior Arctic Ocean, Journal of Physical Oceanography, (2020)
https://journals.ametsoc.org/view/journals/phoc/aop/JPO-D-20-0054.1/JPO-D-20-0054.1.xml

41
Arctic sea ice / Re: MOSAiC news
« on: December 15, 2020, 02:28:57 PM »
A strong anti-cyclone arising on the Beaufort/Chukchi side on Dec 8th is projected to continue at least through Dec 20th, enveloping the whole Arctic Ocean. High pressure reached 1053 hPa late on Dec 13th with winds attaining 106 km/hr, shown in the mp4 below of eleven days of 3-hour GFS weather.

https://www.nature.com/articles/s41467-019-13299-8   cyclone tracker
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2017GL076446 Beaufort Gyre collapse

The Polarstern did not encounter sustained winds this strong during its entire year, winds peaking at 23 m/s vs 29.6 here. However lesser storms did cause dramatic ice fracture as shown on 6-hour bow radar.

Because so little open water remains now, wind fetch is short and no swells can develop. Ice has blown into the Chukchi (rather than forming there) where it has mostly melted so far.

Initially the wind pattern supported ice co-rotation as a classical Beaufort Gyre though the storm quickly broadened so much that ice would only continue in a partial gyre along the Alaskan coast but never return to the western CAA.

Only a handful of days in recent years have supported the Gyre pattern according to OsiSaf ice motion (https://tinyurl.com/yd5fz5ww). Prior to OsiSaf's start-up in Oct 2015, sea ice motion was not quantitatively tracked ocean-wide with any gridded accuracy. However buoys completed Beaufort Gyre circuits in the 1980's (though they don't today) and low resolution ice age movies are available for 1984-2019.



Because wind stress on the ice pack is been very high and unequally applied, many new leads and pressure ridges are expected. With high pressure, clouds are scarce and visibility is excellent on Suomi band 15 infrared as displayed at WorldView. Leads, even refrozen, are heat leaks and show up as bright lines.

This storm provides a validation opportunity: comparison of satellite-observed leads with neXtSim calculated and forecast leads, per its CMEMS displays of diminished ice area fraction and ice thickness. However current product glitches and today's implementation of a new rheological model suggest a few days wait is advisable.

However 11 days of neXtSIM as currently offered mostly shows healing of existing fracture features during the storm along with older ones in the CAB persisting. The extent with which neXtSIM agrees with Suomi band-15 still needs to be determined.

Quote
WHITE OCEAN
New product Arctic Ocean Wave Hindcast
Updated of the stand-alone ice model for the Arctic Ocean Physics Analysis and Forecast (new rheological model used)
Upgrade of the Baltic Sea ice thickness automated products – by including Sentinel-1 IW VV/VH mode
Additional variables in Arctic Ocean ice chart product (total ice concentration, ice type, ice state of development, melting states) –format shapefile
Arctic sea ice displacement at low and medium resolution (sensors ASCAT/MetOp-C & AMSRE/AMSR2)
New Product based on Sentinel-1 satellite images for sea-ice applications covering a part of the Arctic Ocean (in Geotiff format)
https://marine.copernicus.eu/services-portfolio/product-improvements/#dec2020

42
The politics / Re: Brexit...
« on: December 15, 2020, 12:22:29 PM »
I will award myself a bonus point in the Category ´Aisling´ for knowing her last name is actually O´Sullivan.  ;)

...and a bonus point for Kassy for having a friend named Aisling.

Total points: 2
'Must do better' - recommendation: several nights in the nearest Irish pub having the craic, talking to actual Irish people, for educational purposes only, you understand.

43
Antarctica / Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE
« on: December 14, 2020, 03:30:58 PM »

You really made me laugh this time. So predictable,  so not science.
Good to know, that's what the Pansa is all about  ;D

Quote
In Briner, the chart is in the lower panel of figure 14.

Thanks, i have found it now - so it is doctored after all.  ::)

Quote
You spend time like high priests in the inquisition to track down where that annotated graph came from.

Perhaps you should spend more time to check your sources. IMHO, the figure you showed is grossly misleading.
a) In the form you presented it, it is not contained in the Briner et al (2016) paper. It contains additional information which should at least be noted (if you quote something and change it, it is common [scientific] practice to say what you have changed).
Otherwise it is misleading - that the figure in its revise beauty does come from known denier-plattforms is telling enough.
 
b) The revised figure is also misleading, because it compares apples to oranges.

The Holocene Climate Optimum (HCO) is indeed an interesting period. It imho shows how sensible our climate system is, even  to minor forcings (that is how I read kassy's post as well, but i might have read it wrong).

If we want to compare it to what is happening now, we have to keep in mind though: During the  HCO earth's climate system had plenty of time to find its quasi-equilibirium - until the forcing changed again.
 
Currently we are fare from that equilibrium. On the contrary, we are still  increasing the forcing. Especially those parts of the climate system that are known as slow feedbacks (the GIS for instance or to a minor extent the ASI) have just started to change. 

Comparing the current changes of the GIS to the end-result of the changes forced during the HCO is, again, misleading: if we pretend that we are comparing like with like.

But that is exactly what the revised figure from Briner 2016 is meant to say: Hey, there is not much to worry about , the climate changed much more even  in the recent past ... . It completely ignores however that most of the slow feedbacks (GIS, WAIS, etc. ) are still to come.


You used the figure and said: "That figure also puts the current ice losses at the GIS in some perspective..."

Well it puts it into a perspective, but in a skewed one ... thats not science either.




44
Antarctica / Re: Sea Ice Extent around Antarctica
« on: December 13, 2020, 09:42:13 AM »
Quote
That may be true in west Antarctica.  In East Antarctica, the story is a bit different.  Increased snowfall has resulted in increasing glacial mass, and consequently, sea ice.
Such certainty with no support given on a scientific blog .
As usual from one of our resident .....

https://www.pnas.org/content/116/4/1095
Four decades of Antarctic Ice Sheet mass balance from 1979–2017
 View ORCID ProfileEric Rignot,  View ORCID ProfileJérémie Mouginot, Bernd Scheuchl,  View ORCID ProfileMichiel van den Broeke, Melchior J. van Wessem, and  View ORCID ProfileMathieu Morlighem
PNAS January 22, 2019
Abstract
Quote
We use updated drainage inventory, ice thickness, and ice velocity data to calculate the grounding line ice discharge of 176 basins draining the Antarctic Ice Sheet from 1979 to 2017. We compare the results with a surface mass balance model to deduce the ice sheet mass balance. The total mass loss increased from 40 ± 9 Gt/y in 1979–1990 to 50 ± 14 Gt/y in 1989–2000, 166 ± 18 Gt/y in 1999–2009, and 252 ± 26 Gt/y in 2009–2017. In 2009–2017, the mass loss was dominated by the Amundsen/Bellingshausen Sea sectors, in West Antarctica (159 ± 8 Gt/y), Wilkes Land, in East Antarctica (51 ± 13 Gt/y), and West and Northeast Peninsula (42 ± 5 Gt/y). The contribution to sea-level rise from Antarctica averaged 3.6 ± 0.5 mm per decade with a cumulative 14.0 ± 2.0 mm since 1979, including 6.9 ± 0.6 mm from West Antarctica, 4.4 ± 0.9 mm from East Antarctica, and 2.5 ± 0.4 mm from the Peninsula (i.e., East Antarctica is a major participant in the mass loss). During the entire period, the mass loss concentrated in areas closest to warm, salty, subsurface, circumpolar deep water (CDW), that is, consistent with enhanced polar westerlies pushing CDW toward Antarctica to melt its floating ice shelves, destabilize the glaciers, and raise sea level.

This is one of many papers that attempt to quantify mass balance of the Antarctic. Other papers come to different conclusions.
I do not know... sorry We do not not for 100% certainty what is happening with the east antarctic land ice mass balance .
Most actual experts seem to have the opinion that it is probably not good for the future of land ice in any region of the antarctic.

Seasonal Antarctic Sea ice extent .
https://www.nap.edu/read/24696/chapter/2
The consensus seems to be..  Sea ice extent around Antarctica  is more dependent on natural variations in wind and currents than land ice mass balance with perhaps the human caused Antarctic ozone hole also having a role .

 
 

 

45
Arctic sea ice / Re: MOSAiC news
« on: December 12, 2020, 05:50:36 PM »
The two animations below show the growth of ice thickness this fall. The Cryo2Smos product has colored rings at 0.5, 1.0 and 2.0 meters of thickness that move radially out from the CAA allowing the 'front' to be tracked across the available dates Oct 15 to Dec 09th. (The radial motion will reverse direction shrink the perimeter in melt season.)

To actually measure growth rate between two rolling dates say ten days apart at a given position, the netCDFs can be subtracted in Panoply to generate that map.

The second mp4 shows Smos-Smap ice thinness (less than a half meter) progression. It would be somewhat problematic to measure the earliest rates of ice growth because of the complexities of bottom ice formation (which involved platelets in one published Mosaic underwater observation). Mosaic otherwise has not released any ice growth data though some of its buoys have.

neXtSIM apparently assimilates Smos ice thickness but the Bremen archives do not provide this at during summer months nor would Smos provide any data on the main thicker ice pack. Topaz4 may be the real source of ice thickness so its source (observation? model?) has to be chased down. If fresh updates are put in every morning, then neXtSIM is only calculating the hourly interpolations though neXtSIM-F is taking ice thickness seven days forward with its forecast.

Note mp4's provide first frame stills before playing and last frame stills if looping is turned off. There is no good way to provide end pauses in loops in contrast to gifs where this can be specified. Neither gimp nor ImageJ make, open, play or edit mp4; QuickTime can play and join clips; ezgif.com offers various free mp4 editing tools such as crop, speed, rotation, reverse, re-size, conversion back to gif etc.

46
Arctic sea ice / Re: The 2020/2021 freezing season
« on: December 11, 2020, 04:41:09 PM »
Ice growth so far this refreeze, at increments of 10 days.

47
Science / Re: Carbon Cycle
« on: December 10, 2020, 10:12:46 PM »
The Greening of the Earth is Approaching Its Limit
https://phys.org/news/2020-12-greening-earth-approaching-limit.html

An international study published today in Science concludes that the fertilizing effect of CO2 is decreasing worldwide, and that the reduction has reached 50% progressively since 1982 due basically to two key factors: the availability of water and nutrients.

"There is no mystery about the formula, plants need CO2, water and nutrients in order to grow. However much the CO2 increases, if the nutrients and water do not increase in parallel, the plants will not be able to take advantage of the increase in this gas", explains Professor Josep Peñuelas. In fact, three years ago Prof. Peñuelas already warned in an article in Nature Ecology and Evolution that the fertilizing effect of CO2 would not last forever, that plants cannot grow indefinitely, because there are other factors that limit them.

... "These unprecedented results indicate that the absorption of carbon by vegetation is beginning to become saturated. This has very important climate implications that must be taken into account in possible climate change mitigation strategies and policies at the global level. ... If the fertilizing capacity of CO2 decreases, there will be strong consequences on the carbon cycle and therefore on the climate.

The team based it's conclusions on data obtained from hundreds of forests studied over the last 40 years. "This data show that concentrations of essential nutrients in the leaves, such as nitrogen and phosphorus, have also progressively decreased since 1990," explains researcher Songhan Wang, the first author of the article.

The team has also found that water availability and temporal changes in water supply play a significant role in this phenomenon. "We have found that plants slow down their growth, not only in times of drought, but also when there are changes in the seasonality of rainfall, which is increasingly happening with climate change," explains researcher Yongguan Zhang.





S. Wang el al., "Recent global decline of CO2 fertilization effects on vegetation photosynthesis," Science (2020)
https://science.sciencemag.org/content/370/6522/1295

... Our analyses showed a significant and spatially extensive decline in β, which implies a substantial reduction of the positive effects of increasing atmospheric CO2 on terrestrial carbon uptake.

48
Permafrost / Re: Permafrost general science thread
« on: December 10, 2020, 01:40:18 PM »
A study on soil temperatures in Russia (open access)

https://www.sciencedirect.com/science/article/pii/S092181812030285X?dgcid=rss_sd_all
Significant shallow–depth soil warming over Russia during the past 40 years
Quote

Highlights
• Significant warming of shallow ground occurred in Russia during 1975–2016.

• Trends in soil temperature vary with depth in different frost-related areas.

• For the region as a whole, the intra-annual variability of soil temperature increased.

• Trends in soil temperature significantly respond to changes in snow cover.

3. Results
3.1. Trends in soil temperature from 1975 to 2016
It is found that MAST increased at 279, 286, and 197 sites, while it decreased at 4, 2, and 2 sites, and remained stable (within measurement accuracy) at 32, 31, and 17 sites at depths of 0.8, 1.6, and 3.2 m, respectively (Fig. 2a). The greatest warming of MAST at shallow depths (0.8 and 1.6 m) is 1.09 ± 0.20 °C/decade (mean ± SD, P < 0.01) at a site located in the northern Siberian permafrost area. At a deeper level (3.2 m), the greatest warming in MAST occurred in central Siberia at 0.89 ± 0.12 °C/decade (P < 0.01). However, a few sites that had decreased MAST are mainly located in the permafrost area. Trends in MAST from −0.11 to −0.21 °C/decade were observed at four sites at 0.8 m. For the depths of 1.6 and 3.2 m, MAST of the two sites located in the continuous permafrost area decreased by 0.15 ± 0.09 (P > 0.05) and 0.11 ± 0.05 °C/decade (P > 0.05), respectively, and a decrease in MAST at 3.2 m of 0.36 ± 0.06 °C/decade (P < 0.05) occurred at a seasonal frost site.


3.2. Impact of snow cover characteristics on soil temperature
It is found that MAST was, in general, higher than MAAT, accounting for 0.64 of MAAT at all sites (Fig. 5a). Meanwhile, the sites with smaller SSD and SCD (lighter dots) are closer to the 1:1 line, indicating the role of snow cover in offsetting MAST against MAAT. SSD and SCD were both positively related to ΔT0.8 (Fig. 5b and c), whereas the relations between ΔT0.8 and two snow cover parameters are different, with ΔT0.8–SSD relations being more linear than ΔT0.8–SCD relations. Moreover, SCD shows a higher R2 (0.49) than SSD (0.40) in the linear relationship with ΔT0.8.



Fig. 5. a. Relationships between the mean annual soil temperature (MAST, 0.8 m) and air temperature (MAAT). In total, 9722 annual values at 269 sites during 1975–2016 are scattered with colour representing the annual sum of snow depth (SSD, left) and snow cover duration (SCD, right). b, c. Relationships between the annual offset (ΔT0.8) and SSD (b) and SCD (c) with permafrost distribution.

4. Discussion
The annual mean and extreme soil temperatures of shallow ground significantly increased from 1975 to 2016 in Russia. The majority of the sites had warming trends, and a few sites mainly located in the permafrost areas remained thermally stable and even cooled during the period. The soil warming in the continuous permafrost area was faster than that in the discontinuous permafrost and seasonal frost areas at 0.8 m and 1.6 m, and was slower at 3.2 m (Fig. 4). Moreover, the annual maximum soil temperature increased faster than the minimum soil temperature, which leads to increased intra-annual variability of soil temperature (Fig. 3). The study provides an unprecedentedly detailed picture of soil temperature evolution over the past four decades in Russia by quantifying the trends in the multilayer soil temperature parameters at 457 sites.

49
The rest / Re: Good music
« on: December 10, 2020, 01:48:57 AM »
King Crimson - Epitaph

The song was written during the nuclear arms race and cold war but its messages still resonate today.



Lyrics:

The wall on which the prophets wrote
Is cracking at the seams
Upon the instruments of death
The sunlight brightly gleams
When every man is torn apart
With nightmares and with dreams
Will no one lay the laurel wreath
When silence drowns the screams

Confusion will be my epitaph
As I crawl a cracked and broken path
If we make it, we can all sit back and laugh
But I fear, tomorrow, I'll be crying
Yes, I fear, tomorrow, I'll be crying
Yes, I fear, tomorrow, I'll be crying

Between the iron gates of fate
The seeds of time were sown
And watered by the deeds of those
Who know and who are known
Knowledge is a deadly friend
If no one sets the rules
The fate of all mankind, I see
Is in the hands of fools

The wall on which the prophets wrote
Is cracking at the seams
Upon the instruments of death
The sunlight brightly gleams
When every man is torn apart
With nightmares and with dreams
Will no one lay the laurel wreath
When silence drowns the screams

Confusion will be my epitaph
As I crawl, a cracked and broken path
If we make it, we can all sit back and laugh
But I fear, tomorrow, I'll be crying
Yes, I fear, tomorrow, I'll be crying
Yes, I fear, tomorrow, I'll be crying
Crying, crying
Yes, I fear, tomorrow, I'll be crying
Yes, I fear, tomorrow, I'll be crying
Yes, I fear, tomorrow, I'll be crying
Crying

50
Antarctica / Re: What's new in Antarctica ?
« on: December 07, 2020, 06:23:06 AM »

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