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Messages - Stephan

Pages: [1] 2 3 ... 18
1
Antarctica / Re: Sea Ice in Amundsen Sea / Pine Island Bay
« on: Today at 09:52:08 PM »
Liberation of some sea ice between Thwaites and B-22 iceberg.
In the last month NW of Thwaites Ice Tongue the sea ice opened and fractured into hundreds of floes. They were kept prisoner between the fast ice in the south and the (slowly NW moving) iceberg B-22. With SW winds in the past week some of the ice could escape. Now the wind blows again from the SE. On the western end of that open sea there are a lot of grounded icebergs sitting on an underwater ridge. In addition a bigger iceberg has flown there and got stuck and blocked the flow-out of the sea ice. I have called it "Cork". Now a bigger part of it has calved and after that it turned counterclockwise (40°) to give way to the sea ice which is now slowly flowing out.

The first image shows the area I am writing about. Green circled is the open water with the sea ice on it. The orange square is the region of the "Cork" and the area of the second image.
The second image gives the details. All grounded icebergs are circled in yellow. So it is not easy for an ordinary sea ice floe to move around these obstacles...

2
Antarctica / Re: PIG has calved
« on: Today at 09:03:40 PM »
Two minor calvings of PIIS-MIS visible on the actual EOSDIS picture.
The first one on the NE edge - there are two little new icebergs (circled in green).
The second one along the former tip (circled in green). This calving hasn't been completed yet, but should be visible in more detail tomorrow on Sentinel.
"Schrödinger's tip" has already moved about 26.5 km in W direction (circled in yellow).

The latest minor calvings on the NW edge of SWT (circled in blue) are very hard to see due to the low resolution of EOSDIS. So the actual calvings are bigger than that paolo reported about this afternoon.

3
Antarctica / Re: PIG has calved
« on: Today at 07:35:04 PM »
I call this one "Schrodinger's Tip"
That is a good one.

4
Antarctica / Re: PIG has calved
« on: Today at 07:33:43 PM »
Thank you for this. I have chosen the 26th and finally received the 25th picture.

5
Antarctica / Re: PIG has calved
« on: Today at 07:14:04 PM »
Thank you paolo for that latest information. Three days ago I reported about the NW tip of SWT and now there is new calving activity...

Unfortunately I have no access to the Jan 25 or 26 pictures yet.

edit:
If this tipping point gets lost (and only isolated grounded icebergs remain there) and on the other side (along the Cork) the connection to PIIS-MIS is no longer I expect a speeding up and rapid calving of the SWT. The cracks are already there...

6
Science / Re: 2020 Mauna Loa CO2 levels
« on: Today at 06:07:11 PM »
Outlook:
Next week last year averaged at 412 ppm with an extreme intra-day variability. This year it looks much smoother; I expect an annual increase around 1.75 ± 0.25 ppm.
The Sunday evening Mauna Loa CO2 information is available:

Week beginning on January 19, 2020:     414.12 ppm
Weekly value from 1 year ago:               412.19 ppm
Weekly value from 10 years ago:            388.27 ppm
Last updated: January 26, 2020

The increase is at the upper end of my outlook. From Jan 21 on the data has left the smooth increase of the last weeks, but went up and down like a yo-yo. The last three days were "unavailable" because of a high intra-day fluctuation.

Outlook:
Last year next week averaged at 411 ppm. Therefore an annual increase of at or above 2.5 ppm is very likely. Even a 3 ppm increase is not impossible. Hard to give an exact number, because the last three days do not offer a predictable trend for the next days...

7
If I use the radiative forcing from the table and compare that to the concentration of each GHG for 2016 I calculated the following factors with which the concentration has to be multiplied to achieve that radiative forcing:
CO2 = 1 (per definition)
CH4 = 57
N2O = 128
SF6 = 116,000
Using these factors one can adjust the concentration table to the radiative forcing of each gas.
_____________

Question: In the ORNL table there is the line: "increased radiative forcing". If I take this seriously, I subtracted the pre-industrial values from the actual values and receive new, modified factors:
CO2 = 1 (per definition)
CH4 = 28
N2O = 213
SF6 = 34,100
Is this a better way to calculate the CO2 eq?

8
Science / Re: Where are we now in CO2e , which pathway are we on?
« on: January 25, 2020, 10:31:13 PM »
Don’t forget the halocarbons.
I didn't mention them because I only took the four "NOAA gases" that are reported on https://www.esrl.noaa.gov/gmd/ccgg/trends/index.html in a regular way. Of course the halocarbons are relevant and must be included into any realistic calculation of the GHG in Earth's atmosphere.

9
Science / Re: Where are we now in CO2e , which pathway are we on?
« on: January 25, 2020, 09:49:10 PM »
While writing these lines a further question came into my mind:
Is a simple addition right at all? Maybe the IR spectra of the molecules (especially CO2 and N2O) overlap and reduce each other by some interference?

10
Science / Re: Where are we now in CO2e , which pathway are we on?
« on: January 25, 2020, 09:26:33 PM »
Stephan, could you please post your calculation and the numbers you used?
I re-calculate for June 2019 (recommended by ASLR)
CO2
concentration 413.92 ppm
factor 1
resulting 413.92 ppm CO2 eq

CH4
concentration 1.8596 ppm
factors 84 (20 y) and 28 (100 y)
resulting 156.21 or 52.07 ppm CO2 eq
adjusting mole weight 56.80 or 18.93 ppm CO2 eq.
→ this was one of my questions whether this has to be done or is it already implemented in the GHG factor? This makes my CH4 value so low


N2O
concentration 0.3318 ppm
factor 264 (I didn't use factor 265 for 100 y, so I used 264 for both times)
resulting 87.60 ppm CO2 eq
no adjust of mole weight necessary

SF6
concentration 0.00093 ppm
factors 17,500 (20 y) or 23,500 (100 y)
resulting 0.17 or 0.23 CO2 eq
adjusting mole weight 0.58 or 0.77 ppm CO2 eq
(same question as above, makes SF6 value much higher because it is so heavy)


The sum of the bold written black lines gives me the same value as yours, nanning (apart from the different month used) 657.90 ppm CO2 eq (20 y) or 553.82 ppm CO2 eq (100 y)
Including the mole weights the values are lower: 558.89 ppm CO2 eq (20 y) or 521.22 ppm CO2 eq (100 y)

11
Science / Re: Where are we now in CO2e , which pathway are we on?
« on: January 25, 2020, 08:43:57 AM »
Re-posted from the 2020 Mauna Loa CO2 thread:
Thank you Stephan. Since you are regularly updating several GHG readings, would it be possible to add a CO2e figure?
In that way we'll have the cumulative GHG effect updated. I know it depends on assumptions but you can put those in.
nanning,
I will do it in the next time. I have the monthly reading of four gas concentrations (CO2, CH4, N2O and SF6) on my PC, in different files, and I can put them together.
I did it, but the sum differs from what I saw from gerontocrat's posting further upthread where he provides NOAA's annual table.
I took the monthly concentrations (beginning from 2000 on, before that date I do not have all the four gases) and multiplied CH4 with the factors 85 (20 years) and 28 (100 years), N2O with 264 (20 & 100 years), and finally SF6 with 17500 (20 years) and 23500 (100 years), using the conversion factors from the later IPCC report. Then I looked up the definition of these CO2 equivalents, which are not given in moles, but in kg and converted the numbers by taking their molecular weight.
I end up with the latest data (Sep 2019) with the following values (100 years equivalent):
CO2: 408.54
CH4:   19.05
N2O:   87.65
SF6    0.78
sum: 516.01
This sum is higher than the CO2 eq given further upthread. Also the proportions of the ratio CH4 to N2O differs completely from NOAA's table. Where is the error?

12
The rest / Re: Good music
« on: January 24, 2020, 10:08:04 PM »
And my favourite from Francesco Puccioni from Roma, aka Mike Francis
Don't Start Givin' Up from his "Flashes of Life" album 1988

Enjoy the music - surprising harmony changes:



13
The rest / Re: Good music
« on: January 24, 2020, 09:57:12 PM »
Back to the (early) eighties...

A Hot Summer Night With Donna
The "we want more" track from her tour 1983, supported by her daughter Mimi.

State Of Independence from her 1980 album "Donna Summer" sung all the way live and she can sing:


14
Antarctica / Re: What's new in Antarctica ?
« on: January 24, 2020, 08:31:28 PM »
Really pretty crazy.
I hope this type of exercise remains voluntary and not mandatory...  ;)

15
Antarctica / Re: PIG has calved
« on: January 24, 2020, 04:12:11 PM »
and the joint's still there
thinner and weaker than never before

16
Science / Re: 2020 Mauna Loa CO2 levels
« on: January 24, 2020, 04:09:40 PM »
I have been thinking that it would be nice to have a thread here which tracked where we are wrt several scenarios.

So maybe we can combine the CO2e data + The Carbon Clock data in a thread where we also compare the outcomes to the RCP scenarios?

This would leave the Mona Loa Thread for the ML numbers and collect CO2e in a thread where it is directly useful.

Lets call it something like:
Where are we now in CO2e and which pathway are we on/how much budget do we have left?

Feel free to improve that title.
Good idea, kassy. I'd also prefer to have the CO2 / CH4 / N2O / SF6 concentration threads (comparable to the ASI Extent thread - bookkeepuing type of thread) and a separate thread about CO2 eq (how to calculate and evaluate with respect to carbon budgets and RCP scenarios).

17
Antarctica / Re: PIG has calved
« on: January 24, 2020, 08:43:13 AM »
So, how many meters are left between the new calving front and the western end of R2?

18
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: January 24, 2020, 08:17:20 AM »
If 2020 marches further upwards, it will soon fall off of the "top 15" list. 2009, 2007 and 2004 are not out of reach, when increases well above average continue...

19
Arctic sea ice / Re: Global sea ice area and extent data
« on: January 24, 2020, 08:14:33 AM »
The season-typical decrease of Global Sea Ice Extent has stalled completely in the last days and increased from Jan 22 to Jan 23. It has almost matched the 2010s average and is only 0.76 M km² apart from the 2000s average. This is the smallest difference I have noticed since I started to watch global sea ice in 2016. Mainly the much less than average decrease in the last weeks on the Antarctic side has led to this situation.

20
Antarctica / Re: Thwaites Glacier Discussion
« on: January 23, 2020, 10:47:12 PM »
The latest Sentinel picture gave insight into the further development on the "peeling-off" of the Thwaites Ice Tongue.
The flow direction remains the same as it has been on Dec 24 (see my posting above) and is indcated by blue arrows. Therefore the gap has widened massively (large pale green circle) and lengthened in S direction (small pale green circle). A newly developed crack SE of it (red lines) seems to indicate that the "peeling off line" will march further southeast and probably include all the ice west of that N-S crack.
The NW directed movement also makes the gap between the Thwaites Ice Tongue and the icebergs west of it smaller, because they move in NNE direction.

In addition I still see the mini polynya which I had "explained" by the sunk iceberg (pale magenta circle)  ;)

See attached picture

21
Science / Re: 2020 Mauna Loa CO2 levels
« on: January 23, 2020, 10:20:39 PM »
Thank you Stephan. Since you are regularly updating several GHG readings, would it be possible to add a CO2e figure?
In that way we'll have the cumulative GHG effect updated. I know it depends on assumptions but you can put those in.
nanning,
I will do it in the next time. I have the monthly reading of four gas concentrations (CO2, CH4, N2O and SF6) on my PC, in different files, and I can put them together.
I did it, but the sum differs from what I saw from gerontocrat's posting further upthread where he provides NOAA's annual table.
I took the monthly concentrations (beginning from 2000 on, before that date I do not have all the four gases) and multiplied CH4 with the factors 85 (20 years) and 28 (100 years), N2O with 264 (20 & 100 years), and finally SF6 with 17500 (20 years) and 23500 (100 years), using the conversion factors from the later IPCC report. Then I looked up the definition of these CO2 equivalents, which are not given in moles, but in kg and converted the numbers by taking their molecular weight.
I end up with the latest data (Sep 2019) with the following values (100 years equivalent):
CO2: 408.54
CH4:   19.05
N2O:   87.65
SF6    0.78
sum: 516.01
This sum is higher than the CO2 eq given further upthread. Also the proportions of the ratio CH4 to N2O differs completely from NOAA's table. Where is the error?

22
Antarctica / Re: PIG has calved
« on: January 23, 2020, 08:03:42 PM »
I analysed the latest development at the E end of the SWT/The Cork area (Dec 27, 2019 vs. Jan 22, 2020).
I didn't detect any microcalving. But some of the cracks have lengthened and widened (marked in red). The triangle in the SW of the Cork has been further squeezed. The new crack in the south of the cork has massively widened (circled in green). I think it will separate soon from the Cork, thereby loosing its contact to the Southern Ice Shelf (SIS).

See attached picture.

23
Antarctica / Re: PIG has calved
« on: January 23, 2020, 07:37:11 PM »
I analysed the latest Sentinel image of the NW tip of the SW Tributary (SWT)
Grounded icebergs (I think we have lost one of them) are circled in yellow.
New and/or widened cracks are marked by red lines
Some minor or mini calvings have happened (green circles)
The zone of destruction S of the tip, adjacent to the much much slower mowing ice W of the SWT is circled in orange. It shows a general widening of the cracks, one of the smaller icebergs within the cracks has tumbled over. I wonder whether a further calving of the tip will open a way for open waters to reach that area. The general flow direction is noted by blue arrows.

See attached picture.

24
Antarctica / Re: PIG has calved
« on: January 22, 2020, 10:37:39 PM »
Thank you paolo and blumenkraft for the information. Will check the latest Sentinel pictures tomorrow for the development of further features.

25
Science / Re: 2020 Mauna Loa CO2 levels
« on: January 19, 2020, 09:12:35 PM »
Thank you Stephan. Since you are regularly updating several GHG readings, would it be possible to add a CO2e figure?
In that way we'll have the cumulative GHG effect updated. I know it depends on assumptions but you can put those in.
nanning,
I will do it in the next time. I have the monthly reading of four gas concentrations (CO2, CH4, N2O and SF6) on my PC, in different files, and I can put them together. Before I do that I'd like to have widely accepted "exchange rates" [GHG factors] between the different gases. At least for methane there is a large variety of values - ranging from 20 to 160 - around. Maybe this forum can advice me which number to use?

26
Science / Re: 2020 Mauna Loa CO2 levels
« on: January 19, 2020, 09:09:05 PM »
Hefaistos,
you cannot over-interprete a predicted lower increase value in the next week than in this week and speculate about a change in the overall growth pattern. The annual increase is depending on the actual value and the value last year. If - like in this case - there was a jump last year, then, of course, the annual increase is lower.
Please check out the Keeling curve at NOAA. Take a ruler to follow the increase of CO2. You will find that this increase is not linear, but slowly accelerating. And so is it in 2020.

27
Science / Re: 2020 Mauna Loa CO2 levels
« on: January 19, 2020, 06:10:22 PM »
Outlook:
Last year next week had an average of 410.7 ppm. Extrapolating the actual values will result in a 2.3 ± 0.3 ppm increase. From mid January on the values generally rise much higher than in late autumn or December.

My Sunday evening CO2 information:
Week beginning on January 12, 2020:     412.82 ppm
Weekly value from 1 year ago:               410.66 ppm
Weekly value from 10 years ago:             388.41 ppm
Last updated: January 19, 2020

This week I got it right. The annual increase has shifted back to values we saw in December 2019. Nevertheless, an increase of "only" 2.16 ppm would have been unprecedented 30-40 years ago. So we got used to see these high values...

Outlook:
Next week last year averaged at 412 ppm with an extreme intra-day variability. This year it looks much smoother; I expect an annual increase around 1.75 ± 0.25 ppm.

28
Antarctica / Re: PIG has calved
« on: January 19, 2020, 02:18:33 PM »
We should also be aware of the fact that - to my knowledge - the cork is the last solid connection between SWT/SIS on the SW side and the Main Ice Shelf (MIS) of PIIS on the NE side. If this connection is lost, the next solid connection between MIS and SIS is far upstream SE of the "zone of destruction" with hundreds of flosting icebergs. I wonder whether the increasing speed of the MIS will also lead to an extension of the "zone of destruction" further upstream, because the differences in flow speed between MIS and SIS are so huge.

29
Antarctica / Re: PIG has calved
« on: January 19, 2020, 08:25:19 AM »
Thank you for the animation. It is clearly visible that each of the major calvings happens further upstream than before. The next calving will also be at the highest position ever - independently from when it will happen exactly.
Even the speeding up of PIIS-MIS can't make up for this.

30
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: January 16, 2020, 09:38:13 PM »
I wish that Geron and Juan could report on ice areas and extents as large as they were in the 1970s.....

31
Antarctica / Re: Sea Ice Extent around Antarctica
« on: January 12, 2020, 04:40:50 PM »
My best guess for the next week(s) is that the decrease of Antarctic Sea Ice Extent will be slightly above average. If you look at Climate Reanalyzer almost everywhere around Antarctica the sea  surface temperature is slightly above average along the sea ice edge. I wouldn't even be surprised if we have a late minimum this year.

32
Science / 2020 Mauna Loa CO2 levels
« on: January 12, 2020, 04:33:11 PM »
Last year next week had an average of 411.7 ppm. Extrapolating the actual values will result in a 2.3 ± 0.3 ppm increase. From mid January on the values generally rise much higher than in late autumn or December.

I got the weekly value last year wrong (I took the average value of the week later and did not carefully look at the scale of the y-axis - sorry). Therefore my Sunday evening CO2 posting begins with an excuse.

Week beginning on January 5, 2020:     413.37 ppm
Weekly value from 1 year ago:             409.94 ppm
Weekly value from 10 years ago:          388.21 ppm
Last updated: January 12, 2020

The annual increase stays above 3.4 ppm. This is no good news for this year. It has just begun - and unfortunately with this massive increase.
The high variability of the last weeks has disappeared. The values are much more in line, daily and hourly averages.
We have the same CO2 level than in April last year. This means we are three months before schedule.

Outlook:
Last year next week had an average of 410.7 ppm. Extrapolating the actual values will result in a 2.3 ± 0.3 ppm increase. From mid January on the values generally rise much higher than in late autumn or December.

33
Antarctica / Re: Sea Ice in Amundsen Sea / Pine Island Bay
« on: January 11, 2020, 08:43:07 PM »
To bring some more input into this thread I present a picture of the Pine Island Bay (N is to the left) from EOSDIS on Jan 11, 2020. To the lower right you can see the sea ice in front of Thwaites Eastern Ice Shelf, and in the upper right corner you can see the tip of the SW Tributary with its grounded icebergs.
It shows the decomposition of the sea ice NW of Velasco Glacier (circled in green).
I compared the situation with Jan 11 in the last years.
2019 the whole Pine Island Bay was filled with sea ice, so was 2018. 2017, after the big El Niño year the whole Pine Island Bay was free of sea ice, so was 2015. 2016 and 2014 had a mixed appearance. Most part of Pine Island Bay were ice-free, but that NE part of it (the area circled in green and N of it) had an almost complete sea ice cover.

See attached picture.

34
Antarctica / Re: PIG has calved
« on: January 11, 2020, 05:59:14 PM »
Any moment now...
I remember you writing that sentence weeks ago. It has been a very long moment so far...      ;)

35
Antarctica / Re: PIG has calved
« on: January 11, 2020, 04:59:09 PM »
paolo,
thank you a million for keeping us up to date. I still wonder how many days we need to wait before the big calving event happens...

36
Arctic sea ice / Re: Global sea ice area and extent data
« on: January 10, 2020, 08:46:16 PM »
I compared the actual JAXA extent values with the averages (1980s to 2010s) and determined the time difference, when today's values had the same value as the averages of the various decades.

For Jan 09, 2020 the difference in the Arctic to the 2010s average was 0 days. In the Antarctic the difference was 4 days (sum: 4 days)
This difference is larger compared with previous decades:
Arctic Jan 09, 2020 vs. 2000s average 12 days, Antarctic 5 days (sum 17 days),
Arctic Jan 09, 2020 vs. 1990s average 23 days, Antarctic 4 days (sum 27 days),
Arctic Jan 09, 2020 vs. 1980s average 31 days, Antarctic 3 days (sum 34 days).

This difference had been larger in the last years on this date - at the moment neither the Arctic Sea Ice Extent nor the Antarctic Sea Ice Extent is at record lows...

37
Science / Re: Trends in atmospheric CH4
« on: January 10, 2020, 08:07:47 PM »
Thanks, nanning. Got it fixed.

38
Science / Re: 2019 Mauna Loa CO2 levels
« on: January 10, 2020, 08:06:43 PM »
Per Stephan's post:
Does this mean a majority of the voting public are 'winners'?  [see poll]
Or does it mean, collectively, we (the world's citizens) don't care too much about tomorrow (and, therefore, are 'losers')?


Separately, what is the relationship between the figures Ken posted (e.g., 2019 - 2.22) and the one Stephan posted (2019 - 2.7)?
"My" number 2.70 ppm annual increase describes the difference between December 2018 and December 2019 and does not mean the annual increase for the whole year 2019, which composes  of 12 different annual increases, one per each month of the year.

39
Science / Re: Trends in Atmospheric SF6
« on: January 10, 2020, 04:59:24 PM »
The monthly average for September 2019 is available:

September 2019:     10.00 ppt
September 2018:     9.66 ppt
Last updated: January 05, 2020

The annual increase of 0.34 ppt is comparable to the values we saw the last months.

40
Science / Re: Trends in Atmospheric N2O
« on: January 10, 2020, 04:57:46 PM »
The monthly average of September 2019 is available:

September 2019:     332.0 ppb
September 2018:     331.1 ppb
Last updated: January 05, 2020

This is an annual increase of 0.9 ppb, slightly less as in the last months.

41
Science / Re: Trends in atmospheric CH4
« on: January 10, 2020, 04:55:07 PM »
The September 2019 average is avialable:

September 2019:     1870.5 ppb
September 2018:     1860.4 ppb
Last updated: January 05, 2020

The annual increase is 10.1 ppbm, higher than before...

42
Science / Re: 2019 Mauna Loa CO2 levels
« on: January 10, 2020, 04:49:42 PM »
The December 2019 average is available:

December 2019:       411.76 ppm
December 2018:       409.07 ppm
Last updated: January 7, 2020

The annual increase lies at 2.7 ppm

43
Antarctica / Re: PIG has calved
« on: January 09, 2020, 09:32:49 PM »
I bet so! I still can't believe it. It's unreal...

Is that cork-ice compressed and therefore stronger?
I could imagine that this ice has been compressed. And maybe it also has become thicker last year due to the permanent pressure. Just look at the size the cork had one year ago. It was 25% wider (W↔E end in December 2018) than it was end December 2018 (SW ↔ NE end measured, because of its rotation).

44
Antarctica / Re: PIG has calved
« on: January 07, 2020, 09:50:51 PM »
the nothing that holds it all together
East of the Cork there is only about 700 m of ice left (measured from the new calving front to the western end of R2). How long will this "nothing" withstand the forces?

45
Antarctica / Re: PIG has calved
« on: January 07, 2020, 09:13:01 PM »
The latest Sentinel image shows the situation on 2020-01-06 at the western end of PIIS-MIS and on the eastern side the picture has been taken on 2019-12-27. Where these image match an estimation of flow speed is easy if identifiable features are visible on both sides of that "border".

I measured the speed at the R2 rift where both pictures are "matched". The southern rim moved ca. 150 m, whereas the northern rim had a shift of around 200 m. That means the rift R2 has further widened. The daily speed is calculated to 15 m/day, the soon-to-come iceberg moved by about 20 m/day. This movement of 200 m is constant through the northern part of the MIS until the calving front. These are higher values than measured ever before.
At R3 the values are: North rim moved by 150 m, the south rim by "only" 125 m, making this rift also wider, and revealing a speed of the MIS of 12.5 m/day even south of R3.
125 m is also the difference at the southern edge of PIIS-MIS where the zone of destruction begins.
Within the zone of destruction the shift is reduced to around 75-100 m.

At the southern end of the zone of destruction, where the slow Southern Ice Shelf begins, the pictures almost perfectly match (shift < 25 m), indicating that the positioning of the pictures is quite good.

46
Antarctica / Re: PIG has calved
« on: January 07, 2020, 08:39:34 PM »


It must be unique and must not be changed over time.


I agree that we shouldn't change the numbering system. R0 (the thin new crack closer to the calving front) is a good idea to come along with.
We probably talk about days or weeks, not months - and then the cards are mixed newly after the soon-to-happen great calving event.

47
Antarctica / Re: PIG has calved
« on: January 05, 2020, 10:44:59 PM »
Latest development on the tip of SW Tributary:
1. widening of the cracks at the calving front along the tip
2. a lot of microcalvings along the tip of the SWT as well as at the new calving front after the last calving
3. open water in the crack further inland (marked by a red ? in the picture)
4. one of the lately calved icebergs is now grounded (at least temporarily), marked in yellow

See attached picture.

48
Antarctica / Re: Where is D-26 headed?
« on: January 05, 2020, 10:35:38 PM »
Nov 19 to Jan 04: A progress in N direction of about 18 km. Its western edge still is very close to that persistent sea ice field which probably marks shallow waters.
It still has to move another 30 km to reach really open waters.

49
Antarctica / Re: Antarctic Icebergs
« on: January 05, 2020, 10:29:05 PM »
Thank you Mitch, I meant the drift west to east, of course. Got it fixed.

50
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: January 05, 2020, 09:42:55 PM »
I took the monthly extent value for December 2019 and added it into my long-term plot where I calculate the anomalies from 1979 up to now.
The average December extent is now 12,69 M km². December 2019 had an average extent of 11,95 M km², which is 0,74 M km² less than that average and the fifth lowest ever recorded since 1978.
The rapid re-freeze now also into the peripheral seas (see gerontocrat's daily postings) pushed the actual value above the red long term linear trend line by 0,64 M km² (calculated from the linear trend line this December should have been at 11,31 M km²).
The slope of the linear trend line has nevertheless increased by two digits (-0,0560 instead of -0,0558).

See attached graph.

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