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Messages - Stephan

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1
Antarctica / Re: Pine Island Glacier (PIG) Calving and Discussion
« on: May 26, 2020, 09:00:38 PM »
The red line is the major calving including Cork in February 2020. The yellow line includes minor calvings including Cork II in March and April 2020. The orange line summarizes the double calving of the Point, the Keystone, the Crescent and the northern part of SIS from this weekend.

PS: Apart from Cork III and Point 2 there are no other named places left. Let's see how these icebergs, rifts and edges develop to find a common understanding by giving them names and/or numbers in the future.

2
Antarctica / Re: Pine Island Glacier (PIG) Calving and Discussion
« on: May 26, 2020, 05:44:52 PM »
paolo,
I guess you can read my mind. This picture was one I planned to make and to post here. Thank you for doing that so well.  :)

3
Science / Re: 2020 Mauna Loa CO2 levels
« on: May 24, 2020, 04:55:08 PM »
Outlook:
Next week last year had an average of 414.8 ppm. Taking into account the actual downsloping curve I wouldn't be surprised if the annual increase goes even further down than this week.
It is time for the weekly Mauna Loa CO2 posting.
It comes as a surprise, but two weeks ago was not the weekly maximum, this week is slightly higher. We have a broad maximum this year. Therefore the annual increase has risen to 2.25 ppm, the ten year average increase is 2.35 ppm. The values:
Week beginning on May 17, 2020:     416.97 ppm
Weekly value from 1 year ago:          414.72 ppm
Weekly value from 10 years ago:      393.46 ppm
Last updated: May 24, 2020

Apart from yesterday ("unavailable") the whole week had constant CO2 values with a very small intra-day variability.

Outlook:
Last year next week had an average of 414.2 ppm. When the plateau that has been reached now still holds on, then the annual increase can even move up a little further. It is impossible to say on which date finally the annual cycle with decreasing daily values will have its onset.

4
Greenland and Arctic Circle / Re: Greenland 2020 Melting Season
« on: May 21, 2020, 10:17:59 PM »
I just checked the historical pictures from Freya Gletscher webcam and looked for melt pond formation dates:
2016 first melt pond further downstream June 11, no melt pond at that place at all through August
2017 first melt pond further downstream June 1, melt pond at that place June 6
2018 no melt pond in May, and then - camera not working for a while...
2019 melt pond at that place May 26
So in this little race 2020 is the winner for being as early as never since 2016.

5
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: May 19, 2020, 10:45:55 PM »
Here is my long-term arctic sea ice volume deviation chart. Since December 2019 the values are above the long-term linear trend lines. These differences are larger compared to the early months in 2019. So the slope has slightly decreased compared with early 2019, when I published this graph the last time.

See attached graph.

6
Arctic sea ice / Re: Global sea ice area and extent data
« on: May 13, 2020, 07:43:00 AM »
I evaluated the actual JAXA extent data and compared it with the decadal averages. The actual Arctic Sea Ice Extent was reached 2 days later than today in the 2010s, the actual Antarctic Sea Ice Extent was reached 4 days earlier in the 2010s. This is in sum a difference of 6 days.
Compared to the other decades following differences were observed:
2000s: Arctic +12 days, Antarctic - 6 days, sum = 18 days
1990s: Arctic +24 days, Antarctic - 5 days, sum = 29 days
1980s: Arctic +34 days, Antarctic - 2 days, sum = 36 days
This means more open waters and more warming potential by insulation in the Arctic compared to earlier decades, and more available potential freezing heat in the Antarctic.


7
The door is open, yes. But probably not just because the melting has arrived there... ;)

8
Antarctica / Re: Thwaites Glacier Discussion
« on: May 12, 2020, 07:50:30 PM »
Thank you baking for that information. It is the same observation I made months ago, that there is a center of clockwise rotation close to the NE corner of B-22.
I wonder whether the new SW corner of B-22 may force the broken-off SW part into deeper seas further west of it. You can see the movement of the broken-off part. Otherwise it will stay there almost grounded for a longer period of time.

9
Science / Re: Where are we now in CO2e , which pathway are we on?
« on: May 10, 2020, 09:36:57 PM »
Said and done.
I recalculated the data, now turning from CO2 equivalents into Delta radiative forcing. I checked my calculations with the NOAA table. It worked well for CO2, CH4 and N2O. I didn't find any conversion formula for SF6, therefore I used a factor from the fourth IPCC assessment report https://archive.ipcc.ch/publications_and_data/ar4/wg1/en/ch2s2-10-2.html where I found the factor 0.52 (*10-3) with which the SF6 concentration shall be multiplied to give its additional warming potential. As SF6 has a very low in concentration it does not really matter. The distribution among the gases are:
CO2 74 %
CH4 18 %
N2O  7 %
SF6   0.2 %
In addition I could add the years 1979-2001 for all four "NOAA gases" to my spread sheet. :)

I hope you are satisfied with the attached graph:
(linear fit again doesn't work perfectly due to the acceleration of the concentration)

10
Science / Re: Where are we now in CO2e , which pathway are we on?
« on: May 06, 2020, 07:21:35 AM »
I do not have the resources for that at the moment. My spreadsheet starts (apart from CO2) around 2000, using the NOAA data. I am not sure whether I would be able (as a layman) to find reliable and comparable data for earlier years, especially before Keeling started his experiments in 1958...

11
Science / Re: Where are we now in CO2e , which pathway are we on?
« on: May 05, 2020, 10:57:04 PM »
I add the graph for the NOAA gases (20y and 100y CO2 equivalents) from 2000 to 2020.
Please note that the linear fit does not perfectly match the data. The increase is of exponential nature (see my post in the CO2 thread from today).

12
Science / Re: 2020 Mauna Loa CO2 levels
« on: May 05, 2020, 10:46:07 PM »
I plotted the annual increases of Mauna Loa CO2 from the monthly values from 1959 to 2020.
The best fit for the data is a linear one. Of course the data is noisy. Some years have seen a slow CO2 increase, others (like 2016) had rapidly increasing values. In the long run there is a steady increase of the annual increase. Please keep in mind that this is an increase in slope, which means acceleration.
I do not see any sign for a hiatus or a turn around - I'd like to be able to report such an event...

See attached graph.

13
Science / Re: Where are we now in CO2e , which pathway are we on?
« on: May 05, 2020, 10:34:27 PM »
With the actual values of CO2, CH4, N2O and SF6 for January 2020 (see the posts in the individual threads) there is an annual increase (Jan 2020 vs. Jan 2019) of 2.83 ppm CO2 eq (20 y) or 2.67 ppm CO2 eq (100 y).
This increase is mainly driven (2.37 ppm) by CO2 itself.

14
Science / Re: Trends in Atmospheric SF6
« on: May 05, 2020, 10:31:20 PM »
It is the fifth of the new month and so the average values of the "NOAA gases" are available.
Here is the value of SF6:

January 2020:     10.12 ppt
January 2019:     9.80 ppt
Last updated: May 05, 2020

This value represents a CO2 eq. of about 0.59 / 0.79 ppm. (20 y / 100 y)

The annual increase of 0.32 ppt is at the lower end of the range (since about 2012 the annual increase lies between 0.30 and 0.37 ppt, peaking in 2017).

The NOAA history of atmospheric SF6 goes back to July 1997. If I set an index in Jan 2000 at 100, then January 2020 has a relative value of 225.

15
Science / Re: Trends in Atmospheric N2O
« on: May 05, 2020, 10:28:30 PM »
It is the fifth of the new month and so the average values of the "NOAA gases" are available.
Here is the value of N2O:

January 2020:     332.5 ppb
January 2019:     331.8 ppb
Last updated: May 05, 2020

This value represents a CO2 eq. of 87.8 ppm.

The annual increase is 0.7 ppb. It is clearly at the lower end of the range, but not unprecedented.
I set Jan 2001 = 100 as index. January 2020 has 105.1 - comparable to the increase in methane concentration.

16
Science / Re: Trends in atmospheric CH4
« on: May 05, 2020, 10:26:28 PM »
It is the fifth of the new month and so the average values of the "NOAA gases" are available.
Here is the value of CH4:

January 2020:     1873.5 ppb
January 2019:     1865.0 ppb
Last updated: May 05, 2020

This converts into CO2 eq: 57.2 / 19.1 ppm (20 y / 100 y)

The annual increase of 8.5 ppb is in the upper half of what has been observed in the last years, but much lower than in July-November 2019 (see posts above in this thread).

I set an index of 100 to Jan 2000. January 2020 has a relative value of 105.5.

17
Science / Re: 2020 Mauna Loa CO2 levels
« on: May 05, 2020, 10:23:19 PM »
It is the fifth of the new month and so the average values of the "NOAA gases" are available.
Here is the value of CO2:

April 2020:       416.21 ppm
April 2019:       413.33 ppm
Last updated: May 5, 2020

The annual increase is 2.89 ppm, a bit smaller than in April 2019 and much smaller than in April 2016, but higher than most of the other Aprils in my spreadsheet.

18
Just have a look at western Europe. It looks almost as clean as Iceland or Grønland.

19
Science / Re: 2020 Mauna Loa CO2 levels
« on: May 04, 2020, 10:50:34 PM »
bosbas,
thank you for this comment. I really didn't realize that the data was more than one week old - relying only on the updated date (May 2, 2020) is not enough ???.
Nevertheless, here are the actual values:

Week beginning on April 26, 2020:     416.82 ppm
Weekly value from 1 year ago:             414.45 ppm
Weekly value from 10 years ago:     393.18 ppm
Last updated: May 4, 2020

The annual increase of 2.37 ppm is a bit higher than last week, and very close to the average of the last 10 years (2.366 ppm).

May 3 saw a new daily record (418.12 ppm) since measurements started in 1958. A flattening of this peak should nevertheless be expected, therefore I stay with my

Outlook:
The first week of May 2019 averaged at 414.3 ppm. I guess the actual peak will flatten out. We should expect an annual increase of 2.75 ± 0.25 ppm.

20
Arctic sea ice / Re: The 2020 melting season
« on: May 01, 2020, 02:12:36 PM »
The ice temperatures in 2020 do not differ fundamentally from what has been observed the last years. I had a look athe DMI website (thank you for the link) and found that on May 1, 2019 the temperatures were even higher than this year. 2018 (and also 2014) was cooler, and for 2017 to 2015 I do not see a significant change from today's values. But this comparison is made by eye-balling. There are of course quantitative evaluations available.

21
Antarctica / Re: Sea Ice Extent around Antarctica
« on: May 01, 2020, 01:28:05 PM »
In some formerly stable systems with an intrinsic variability a move towards a tipping point can result in higher variability of the observed values, maybe even with erratic deviations from the long-term trendlines. It is above my pay grade to decide whether Antartic Sea Ice is in (or moves towards) such a state.

22
very nice, gerontocrat.
Looks like there is a lot of spreadsheet work ahead of you. Good luck with that, and looking forward for further nice charts...

23
Science / Re: 2020 Mauna Loa CO2 levels
« on: April 26, 2020, 09:03:40 PM »
Outlook:
Last year's next week averaged at ca. 413.8 ppm. If I extrapolate the actual trend, an annual increase of 2.9 ppm ± 0.3 is what I expect.

It is Sunday evening and time to inform the forum about the actual Mauna Loa CO2 levels.

Week beginning on April 19, 2020:     415.88 ppm
Weekly value from 1 year ago:           413.71 ppm
Weekly value from 10 years ago:        393.25 ppm
Last updated: April 26, 2020

Due to a drop last Tuesday the CO2 concentration is lower than I had expected last Sunday. The annual increase now is 2.17 ppm, slightly below the averaged increase of the last ten years (415.88-393.25)/10 = 2.26 ppm.

Outlook: The next week of last year had an average of ca. 414.3 ppm. The actual values projected into the next week would give an annual increase of only about 1.7 ± 0.3 ppm.

In addition, NOAA presents a short information about the current lockdown caused by CoViD-19 in many countries and its influence on CO2 levels:

Can we see a change in the CO2 record because of COVID-19?
There have been many inquiries whether we can see in our CO2 measurements at Mauna Loa and elsewhere the slowdown in CO2 emissions from the burning of fossil fuels. That drop in emissions needs to be large enough to stand out from natural CO2 variability caused by how plants and soils respond to seasonal and annual variations of temperature, humidity, soil moisture, etc. These natural variations are large, and so far the "missing" emissions do not stand out, but we may see them as the year progresses.
Here is an example: If emissions are lower by 25%, then we would expect the monthly mean CO2 for March at Mauna Loa to be lower by about 0.2 ppm. When we look at many years of the difference between February and March we expect March to be higher by 0.74 ppm, but the year-to-year variability (one standard deviation) of the difference is 0.40 ppm. This year the difference is 0.40 ppm, or 0.33 below average, but last year it was 0.52 ppm below average.

Most of the emissions come from urban areas, so that it may be easier to see the effect downwind of cities, although also in that case they need to stand out from natural variations. Only measurements of carbon-14 in CO2 would enable us to cleanly separate fossil sources of CO2 from ecosystem sources and sinks regardless of how variable the latter are.

24
Science / Re: 2020 Mauna Loa CO2 levels
« on: April 24, 2020, 10:12:10 PM »
Hi nanning,
that is correct - but it is not too far off like I was in the weeks before.
I always try to extrapolate the latest trend of the last week into the next week, which does not always work smoothly, because there are some jumps between the days. And there is that uncertainty deriving from last year's extreme inter-day variations which make an exact assumption of the CO2 concentration of 52 weeks ago quite difficult.

25
Arctic sea ice / Re: Sea Ice Melting Affected by Microplastics?
« on: April 23, 2020, 10:34:11 PM »
The basic building blocks of plastic are cellulose. Currently, cellulose is primarily obtained from petroleum.
Most of the plastic we use does not contain any cellulose. Polyethylene, polypropene, polyurethane, polyvinylchloride, polyterephthalates, polystyrene, polybutadiene and most of the other plastics in our daily lives are completely cellulose-free.
And cellulose is not obtained from petroleum, but from wood or cotton.

(Tried to open the link, but wasn't successful in doing so).

26
Greenland and Arctic Circle / Re: Greenland 2020 Melting Season
« on: April 22, 2020, 10:36:09 PM »
A temperature jump also at Freya Gletscher 1053 m a.s.l. from -18°C to -3°C in the last couple of days. And snow is melting in the sun.
Generally much less snow than in 2018, and less snow than in 2017 and 2016 [2019 had no pictures at that time of the year, the camera was broken for a while].

See attached photo from https://www.foto-webcam.eu/webcam/freya1/

27
Science / Re: 2020 Mauna Loa CO2 levels
« on: April 19, 2020, 07:10:50 PM »
Outlook:
Last year next week averaged at around 413.7 ppm. I expect a slight increase above today's value which fianlly results in an annual increase of about 3 ± 0.3 ppm.
It's Sunday evening and the weekly update on Mauna Loa CO2 levels is ready.
Week beginning on April 12, 2020:     416.27 ppm
Weekly value from 1 year ago:           413.63 ppm
Weekly value from 10 years ago:       392.85 ppm
Last updated: April 19, 2020

This is an increase of 2.64 ppm. This week had a lot of intra-day and inter-day variations, including the second highest ever recorded daily value on April 16 (417.08 ppm). Nevertheless, all days had valid averages.

Outlook:
Last year's next week averaged at ca. 413.8 ppm. If I extrapolate the actual trend, an annual increase of 2.9 ppm ± 0.3 is what I expect.


28
Antarctica / Re: PIG has calved
« on: April 19, 2020, 07:45:17 AM »
paolo,
thanks again for these animations. Please keep on informing us about the latest developments.
baking,
thank you for additional information and discussion.
Have a nice weekend and stay healthy in CoViD19 times

Stephan

29
Antarctica / Re: PIG has calved
« on: April 16, 2020, 08:29:02 PM »
paolo,
thank you very much for keeping us up-to-date.
EOSDIS and Sentinel 2 are almost out of service due to the dark season downunder.

30
Greenland and Arctic Circle / Re: Greenland 2020 Melting Season
« on: April 12, 2020, 10:00:53 PM »
Melting season has started in Southern Grønland.
www.wetteronline.de presents the following forecast for Narssarssuaq (from 12.-26.4.2020):

31
Science / Re: 2020 Mauna Loa CO2 levels
« on: April 12, 2020, 05:38:02 PM »
Outlook:
The second week of April 2019 had an average slightly above 413 ppm. Therefore an annual increase of 3.25 ± 0.25 ppm is very likely.
My sunday evening Mauna Loa CO2 posting is ready.

Week beginning on April 5, 2020:     416.45 ppm
Weekly value from 1 year ago:         412.67 ppm
Weekly value from 10 years ago:      391.12 ppm
Last updated: April 12, 2020

Due to a very high level on Wednesday and Thursday (417.85, the highest value ever measured so far, and weekly average lower than I had estimated) the annual increase is higher than I had expected last Sunday. No CoViD19 effect visible. This brings me to my

Outlook:
Last year next week averaged at around 413.7 ppm. I expect a slight increase above today's value which fianlly results in an annual increase of about 3 ± 0.3 ppm.

32
Thank you grixm - it's amazing how fast the things are starting at Jakobshavn Isbræ.

33
Arctic sea ice / Re: River ice
« on: April 09, 2020, 02:55:27 PM »
Great thread idea, aluminium.
We should also discuss here dates of river flow start in spring in comparison with former years. I remember some McKenzie River discussions from last year, but I can't remember, in which thread they had been posted.

34
Science / Re: 2020 Mauna Loa CO2 levels
« on: April 06, 2020, 09:36:58 PM »
On the 6th of each month NOAA presents the monthly average for the gases they monitor. The values for CO2 are:
March 2020:       414.50 ppm
March 2019:       411.97 ppm
Last updated: April 6, 2020

The annual increase is 2.53 ppm, less than I expected yesterday.

35
Science / Re: Where are we now in CO2e , which pathway are we on?
« on: April 06, 2020, 09:07:26 PM »
With the actual values of CO2, CH4, N2O and SF6 for December 2019 (see the posts in the individual threads) there is an annual increase (Dec 2019 vs. Dec 2018) of 3.16 ppm CO2 eq (20 y) or 2.99 ppm CO2 eq (100 y).
This increase is mainly driven (2.69 ppm) by CO2 itself.

36
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: April 06, 2020, 01:36:39 PM »
I took the monthly extent value for March 2020 and added it into my long-term plot where I calculate the extent anomalies from 1979 up to now.
The average (1979-2020) March extent is now 15.27 M km². March 2020 had an average extent of 14.78 M km², which is 0.49 M km² less than that long-term average.
The higher than average extent gains in February and the more or less parallel to normal development in March kept the actual value well above the red long-term linear trend line by 0.70 M km² (calculated from the linear trend line this March should have been at 14.08 M km²).
The slope of the long-term linear trend line has thus further decreased by two digits (-0.0551 instead of -0.0553).

See attached graph.

37
Arctic sea ice / Re: The 2020 melting season
« on: April 05, 2020, 09:43:19 PM »
Quote
2012 was a shooting star - phut, & it was gone. 2016 was the steady burn that really matters.
But there could be another shooting star in 202X. This will be at least as likely to be the first BOE as is a gradual drop down year by year.
There will be another (at least one) shooting star in 202X, including the first BOE year.

38
Science / Re: 2020 Mauna Loa CO2 levels
« on: April 05, 2020, 09:10:09 PM »
Outlook:
Last year next week had an average of about 412.2 ppm. An annual increase of 3.2 ± 0.3 ppm shall be expected.
The Sunday evening report on Mauna Loa CO2 is ready to go:
Week beginning on March 29, 2020:     415.74 ppm
Weekly value from 1 year ago:             412.39 ppm
Weekly value from 10 years ago:          391.47 ppm
Last updated: April 5, 2020

This time I got it almost right. No stop of the acceleration of CO2 so far. This could also bring the soon to be published annual increase of March close to the 3 ppm range.
Apart from Friday very stable values with almost no intra-day variations.

Outlook:
The second week of April 2019 had an average slightly above 413 ppm. Therefore an annual increase of 3.25 ± 0.25 ppm is very likely.

39
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: April 04, 2020, 06:09:24 PM »
I've moved all the peripheral seas into one section. I think it makes more sense.

I also think it makes more sense. I even would have used the same order (from Okhotsk to Barents)
Thank you anyway for your daily reports on extent and area and for the clear graphs

40
Science / Re: 2020 Mauna Loa CO2 levels
« on: March 30, 2020, 09:03:57 PM »
Thank you wolfpack for this posting and the impressive graph.
I wonder why just the first three months of a year are so horribly noisy. Was it like that already years/decades ago?

41
Science / Re: 2020 Mauna Loa CO2 levels
« on: March 29, 2020, 09:03:02 PM »
I think it is far too early to talk about a CoViD19 effect on Mauna Loa CO2 at this moment.
Two effects came into play last week:
1. The average one year ago was 0.5 ppm lower than the week before
2. The average this week has stopped for two days and re-started with a higher value, in effect 1.25 ppm higher than the week before.
Adding up 0.5+1.25 = 1.75, which is the additional value on the annual increase of 2.5 ppm from one week ago. I think it will normalize soon.

42
Science / Re: 2020 Mauna Loa CO2 levels
« on: March 29, 2020, 05:38:12 PM »
Outlook:
Last year next week averaged at around 411.3 ppm, therefore an increase of 2.75 ± 0.25 seems to be likely.
Surprise Surprise on Sunday evening.

Week beginning on March 22, 2020:     415.52 ppm
Weekly value from 1 year ago:             411.24 ppm
Weekly value from 10 years ago:         390.77 ppm
Last updated: March 29, 2020

One of the highest annual increases I ever had to write about. This time the guess about last year was almost right, but after a stop in the beginning of this week (2-3 days) the recordings started again at around 415 ppm and increased ever since.

Outlook:
Last year next week had an average of about 412.2 ppm. An annual increase of 3.2 ± 0.3 ppm shall be expected.

43
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: March 26, 2020, 07:43:54 PM »
First analysis of the sea ice extent - relative area wise - of this melting season. Last 11 days Mar 15- Mar 25, 2020.
As gerontocrat correctly wrote, it all depended on three seas:
St Lawrence   - 69%
Bering           - 36%
Okhotsk         - 16%
Small and negligible losses (-1 to -4%) in Baffin, Beaufort and Chukchi Seas
Small and negligible gains (+1 to +4%) in Kara, Laptev, Barents and Grønland Seas
The rest was more or less constant.

44
Greenland and Arctic Circle / Re: Greenland 2020 Melting Season
« on: March 24, 2020, 10:34:59 PM »
Hi grixm,
I detected the same yesterday. It was cold the last days, and if it is -20°C or below at noon it should be colder than that during evening, night and morning. I have two possible explanations: The snow was drifted away by the wind or sublimation took place. I do not believe that the sun could heat up the stones above freezing when it is so cold.

45
The rest / Re: Good music
« on: March 22, 2020, 10:28:11 PM »
For those who like instrumental smooth jazz I strongly recommend Rod Lucas from London, who plays this very good relaxing music in his studio twice a week for several hours, including some wine tasting. Check out his latest show:

And please do not forget to give him a donation, if you enjoy it.

46
The rest / Re: Good music
« on: March 22, 2020, 10:24:46 PM »
Fleetwood Mac - Sara (1979)


Hi nanning - this is one of my favourite Stevie Nicks songs and the best tune from Fleetwood Mac's Tusk double LP. Still have it at home and sometimes I play this tune.  :)

47
Science / Re: 2020 Mauna Loa CO2 levels
« on: March 22, 2020, 10:10:54 PM »
Outlook:
(repeated from last week) Last year next week had an average of 412.1 ppm. An annual increase of 2.1 ± 0.2 ppm seems to be likely.
My sunday evening Mauna Loa CO2 posting is now ready:

Week beginning on March 15, 2020:     414.28 ppm
Weekly value from 1 year ago:             411.77 ppm
Weekly value from 10 years ago:          391.23 ppm
Last updated: March 22, 2020

The difficulty in my "predictions" is not a good guess of the average value this week, but a poor guess about the average value last year. The values have had such a big inter-day variability between Jan and March 2019, that it is almost impossible to find the correct average. Anyway, the annual increase of 2.5 ppm is higher than in the last weeks. But it should not be over-interpreted, because of the high fluctuations last year.

Outlook:
Last year next week averaged at around 411.3 ppm, therefore an increase of 2.75 ± 0.25 seems to be likely.

48
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: March 22, 2020, 07:38:19 AM »
Thanks to you, Juan, for keeping us up-to-date day by day.
I checked the JAXA website and found that yesterday was the first day since Jan 13, where the daily value was below 2010s average.

49
Antarctica / Re: Sea Ice Extent around Antarctica
« on: March 20, 2020, 09:38:10 PM »
Ross Sea is freezing over rapidly. Last week there was only open waters, now a lot of very fresh young ice is visible.
17 days later Southern and Central Ross Sea is almost 100 % covered by young sea ice.
See attached picture.

50
Antarctica / Re: Antarctic Icebergs
« on: March 17, 2020, 10:29:37 PM »
As a follow-up to my reply #140 I used the opportunity to analyse the movement of my "pet iceberg" B-22 northwest of Thwaites Ice Tongue.

I chose five different corners (see picture) and looked at the changes of their positions between Jan 22 and March 15, 2020:

A = 3.5 km, N direction of movement
B = 3.5 km, NE direction of movement
C = 1.1 km, ESE direction of movement
D = 1.7 km, WNW direction of movement
E = 2.0 km, NNW direction of movement

This implies a general N movement with a clockwise turn around a centre close to point C. The highest rates are equivalent to an averaged daily movement of 60-65 m.
In the detailed analysis I found some very minor calvings off of the edge from the western side of B-22.

See attached picture.

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