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Messages - Stephan

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1
Antarctica / Re: What's new in Antarctica ?
« on: April 23, 2019, 09:17:36 PM »
WOW.
That's what I'd like to see. Brilliant job, absolutely excellent. Sorry to have only one 'Like' to give...

2
Arctic sea ice / Re: The 2019 melting season
« on: April 23, 2019, 08:47:10 PM »
Just have a look at Laptev and western ESS - first breakup of sea ice from the fast ice front.
And have a look along the eastern shore of Novaja Semlja - strong SW winds open the waters again. The start of a bigger decrease in Kara Sea?

3
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: April 23, 2019, 07:42:48 PM »
This is the weather forecast for Narssasuaq, close to the southern tip of Greenland:
Looks like really melting weather there.

4
Arctic sea ice / Re: Global sea ice area and extent data
« on: April 21, 2019, 08:43:18 AM »
I compared the actual JAXA extent value (April 20) of Arctic and Antarctic with the decadal averages of the 10s, 00s, 90s, and 80s and calculated the cumulative difference of 2019 (example: in the Arctic we are 14 days ahead compared to the 10s, in the Antarctic we are 11 days behind the 10s average, which sums up to 25 days).
Compared to earlier decades this difference is even bigger:
April 20, 2019 vs. 00s: 35 days
April 20, 2019 vs. 90s: 44 days
April 20, 2019 vs. 80s: 50 days
The big difference means that there is less ice to melt in the Arctic this coming melting season (so less energy needed) and more ice to form in the Antarctic this coming freezing season (more freezing energy to be released). In addition you must also take the Albedo effect into account.
The values are slightly smaller than on April 9 as the slope of the averages increase in May (higher melting rates than in April). But the general trend is unchanged. Climate change is on its way!

5
I just discovered a short video about the accelerating melt rate in Antarctica.

One key sentence: "The IPCC expects around 1 foot of SLR until 2100, but the unstable PIG and Thwaites may lead to 5 feet SLR until 2100, if they collapse." It is also about ice-core sampling and a 3,5°C increase of surface temperature along the Antarctic Peninsula during the last 70 years.
It is not very scientific, but a good explanation for non-scientists and newbies.

6
Greenland and Arctic Circle / Re: What's new in Greenland?
« on: April 20, 2019, 07:53:19 PM »
Thanks tealight. Great work, even if you didn't need weeks or months to do that.
May I kindly ask you to do the same with PIG/PIIS and Thwaites (&Haynes/Smith/Kohler/Pope) Glaciers in Antarctica? Thanks a million in advance.

7
Arctic sea ice / Re: The 2019 melting season
« on: April 17, 2019, 10:35:24 PM »
OK, here is my crappy graph- ....
Thank you Sebastian. The trend is clearly going down, and it is of course overlaid by individual weather patterns each year, whose influence is bigger than the trendline which makes the graph look very "spiky". But this is normal for these kind of graphs.

8
Science / Re: 2019 Mauna Loa CO2 levels
« on: April 16, 2019, 10:40:22 PM »
Probably, but do you recall or find which IPCC report iteration (esp. AR5) had the RCP 8.5 hitting 500 ppm CO2 by 2050? I don't recall one off hand.

AR5

https://www.ipcc.ch/site/assets/uploads/2018/05/SYR_AR5_FINAL_full_wcover.pdf
Could you please give a page number or a chapter title of this IPCC report where the projections of CO2 concentration from today until 2100 are plotted (or listed) under the different RCP scenarios?
Thanks Stephan
I found it. It is on page 74. And 2050 will have around 500 ppm CO2 as expected with an annual growth of ca. 3 ppm from now on (see postings above).

9
Science / Re: 2019 Mauna Loa CO2 levels
« on: April 16, 2019, 09:50:15 PM »
Probably, but do you recall or find which IPCC report iteration (esp. AR5) had the RCP 8.5 hitting 500 ppm CO2 by 2050? I don't recall one off hand.

AR5

https://www.ipcc.ch/site/assets/uploads/2018/05/SYR_AR5_FINAL_full_wcover.pdf
Could you please give a page number or a chapter title of this IPCC report where the projections of CO2 concentration from today until 2100 are plotted (or listed) under the different RCP scenarios?
Thanks Stephan

10
Arctic sea ice / Re: The 2019 melting season
« on: April 16, 2019, 09:08:53 PM »
Falling Records

Will this be the next one?

http://www.yukonriverbreakup.com/

The April 15 picture doesn't look encouraging
A graph with decadal averages would be nice to see a tendency whether the breakup is moved to earlier dates. From a glimpse on the table one could guess that the breakup has moved a little bit, but this needs further statistical analyses.

11
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: April 16, 2019, 07:49:35 PM »
I analysed the ice area of the individual seas from gerontocrat's actual table from April 1 to April 15. Only four seas, all of them in the periphery, show considerable losses (Okhotsk, St. Lawrence, Baffin and Bering). All other seas are constant or increase slightly. From this point of view the melting season has not really begun?!?

12
Antarctica / Re: PIG has calved
« on: April 15, 2019, 09:19:46 PM »
The same question came into my mind. I wonder whether actual altitude measurements exist on PIIS and which height the cliff would have at the actual cracks if it calves at that place, and if this height would meet "MICI criteria".
Please also look at ASLR's fantasic latest news from the WAIS conference (in the multiple meter sea level rise thread).

13
Science / Re: 2019 Mauna Loa CO2 levels
« on: April 15, 2019, 06:46:07 PM »
Where will this end?

This, of course, depends on whether we take effective actions to curb emissions. My guess? Between 600 and 800 ppm.

+500 ppm by 2050 at least (imho)
which simply means an average increase of 3 ppm/year for the next 31 years [to reach 500 ppm]. This is probably too low/too optimistic if we follow the RCP 8.5 path...

14
Science / Re: 2019 Mauna Loa CO2 levels
« on: April 14, 2019, 10:09:44 PM »
And once again, even higher:
Week beginning on April 7, 2019:     413.13 ppm
Weekly value from 1 year ago:       409.46 ppm
Weekly value from 10 years ago:     389.50 ppm
This is an increase of more than 3.6 ppm/year.
Next week it will look a bit better because last year it was around 411 ppm. But the value of today (414.1 ppm) is even 3 ppm higher than that, and one of the highest CO2 concentrations ever recorded since measurements began more than 60 years ago. Where will this end?

15
Arctic sea ice / Re: The 2019 melting season
« on: April 14, 2019, 08:54:10 PM »
As it is recorded since Sep 1 I think that there couldn't hace occurred any melting since then, at least not in higher altitudes (> 300 m). Where does this mass loss come from? Snow drift by strong winds? Sublimation? Compaction (and therefore no mass loss, but slight elevation change, interpreted as mass loss)? I have no idea...

16
Antarctica / Re: PIG has calved
« on: April 14, 2019, 08:39:10 PM »
Just for comparison:
This is the latest clear Sentinel image from Feb 20, 2019.
In my opinion the SW crack (the low left one in Sentinel, the right one in Wipneus' post) has grown, widened and lengthened since then. But for a "perfect" comparison the angles of sunlight should be as identical as possible.
With probably no more Sentinel pictures of that area in the coming Austral winter I hope that others will follow this crack, because: If it cracks completely (= calving) it will be the highest ever calving front of PIIS, also exposing the already broken-up western flank of PIIS to open waters with probably even more (minor) calving events to follow.

Big thank you to Wipneus for this wonderful and clear picture.

17
Greenland and Arctic Circle / Re: Bedrock overlay poll
« on: April 14, 2019, 08:31:21 AM »
I also voted for horizontal overlay.
It would be great, if a comparable overlay were possible for all the Amundsen Bay glaciers and ice sheets!

18
A basic and well understandable video about past, actual and future sea level rise and its causes can be found here:

It is especially useful for non-scientists and newbies.

19
Arctic sea ice / Re: The 2019 melting season
« on: April 12, 2019, 07:35:56 PM »
...and probably another warm and dry summer in Central Europe, at least in N and E Germany??
Wouldn't be good! >:(

20
Science / Re: 2019 Mauna Loa CO2 levels
« on: April 12, 2019, 06:27:57 PM »
Week beginning on March 24, 2019:     411.32 ppm
Weekly value from 1 year ago:        409.90 ppm
Weekly value from 10 years ago:     389.31 ppm
At least this week has settled down (+ 1.42 ppm/y), due to some lower daily values (they are very scattered, compared to last years) in that week and a relatively high weekly value one year ago. The following week has been lower last year, so one should expect a higher yearly increase next week...
...and there it is:
Week beginning on March 31, 2019:      412.21 ppm
Weekly value from 1 year ago:        409.15 ppm
Weekly value from 10 years ago:     389.13 ppm

Return to > 3 ppm/year last week.
Last year the next week was around 409.5. The latest values are again more than 3 ppm higher.
How long will this be going on?

21
Antarctica / Re: Halley base shut down and new crack in Brunt shelf
« on: April 12, 2019, 06:14:12 PM »
In the same sense as BBC (posting above) Wetteronline in Germany presented a short information about the expected calving of parts of the Brunt Ice Shelf:
https://www.wetteronline.de/klimawandel/antarktis-schelfeis-hat-risse-riesen-eisberg-droht-abzubrechen-2019-04-12-aa
The main claim is that this is a natural process as this part of Antarctica has not seen a relevant warming in the past decades (but only air temperature mentioned; no information about increasing sea temperatures)

22
Science / Re: 2019 CO2 emissions
« on: April 11, 2019, 08:26:15 PM »
Thank you for sharing your information sources and their relative weight and importance.
Please keep us updated if newer and more precise information is available and finally good luck with your PhD thesis :-)

23
Antarctica / Re: PIG has calved
« on: April 11, 2019, 07:17:16 PM »
Thank you.
I analysed the picture with the Sentinel images of Feb 20 and March 02, 2019 and couldn't find any difference (apart from the minor calvings I reported some weeks ago). So there was no calving. The floating iceberg must come from somewhere else. With persistent E / NE winds in the last weeks it is likely that it has been driven into the bay close to the calving front of the SW tributary during that time.
_____

Unfortunately there seems to be no (more) EOSDIS and Sentinel pictures of Pine Island Bay or Thwaites area due to the coming Austral winter. So Polarview may remain as only source for changes along the Amundsen Sea calving fronts.

24
Antarctica / Re: PIG has calved
« on: April 11, 2019, 06:50:37 PM »
Could you please zoom out this picture to identify the exact location? Thanks

25
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: April 09, 2019, 09:58:19 PM »
This graph shows how outstanding 2016 was. Looking at the minima animation just posted by uniquorn (Reply#1) in the "ice edge at minimum poll" 2016 looked worst, although it was not at the lowest minimum ever.

26
Arctic sea ice / Re: Ice edge at minimum poll
« on: April 09, 2019, 09:54:41 PM »
I went for the green line, probably a little more than that into direction ESS. Who knows?

27
Antarctica / Re: Thwaites Glacier Discussion
« on: April 07, 2019, 10:21:08 PM »
Weeks of cloudiness in Thwaites area. With Sentinel and EOSDIS - no chance of evaluation what is going on there.
Today the western edge of iceberg B-22-A is visible and I calculated its WNW movement between Feb 4 and Apr 7. It has moved around 3-4 km since then which is in my opinion a sign that it has melted a little bit from below and has lost some of its pinning points.

28
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: April 07, 2019, 10:10:41 PM »
It is time for the monthly update of my extrapolation when the extent [Extent], volume [Volumen] and thickness [Dicke] will reach zero. The extrapolation occured linearly and by a logarithmic function; the latter one almost constantly resulting in earlier times. March value now includes 2019.
As extent, volume and thickness in March 2019 lie all above the long-term linear trend lines it is clear that the BOE for March will take place a few years later than calculated last March. All slopes decreased slightly, and March has, together with April, the smallest slope.

Please note that this is not a forecast but a trend!
See attached table.

29
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: April 07, 2019, 09:59:33 PM »
I took the monthly extent value for March and added it into my long-term plot where I calculate the anomalies from 1979 up to now.
The average March extent is now 15,28 M km². March 2019 had an average extent of 14,55 M km², which is (like it was in February 2019) 0,73 M km² less.
In March 2019 the anomaly is 0,33 M km² above the long-term linear trend (it also was above in Nov 18, Dec 18, Jan 19 and Feb 19), which calculated this March should have been at 14,22 M km². With the strong losses in the last week I expect that April 2019 will lie slightly below this linear trend line.

See attached graph.

30
Arctic sea ice / Re: The 2019 melting season
« on: April 07, 2019, 08:41:55 PM »
I thank uniquorn for this amazing sequence.
For my understanding there is too much ice leaving the CAB through Fram and Nares. Has it been that active the last years? Maybe I can't recall correctly, but it looks like 'much more' than before which is not good...

31
Arctic sea ice / Re: What's new in the Arctic ?
« on: April 07, 2019, 05:22:20 PM »
Another interesting video from the Just Have A Think (JHAT) series:

Main topic is the Blue Ocean Event and its main consequences.
Worth listening to.

32
Arctic sea ice / Re: Global sea ice area and extent data
« on: April 07, 2019, 08:52:21 AM »
I compared the actual JAXA extent value (April 6) of Arctic and Antarctic with the decadal averages of the 10s, 00s, 90s, and 80s and calculated the cumulative difference of 2019 (example: in the Arctic we are 20 days ahead compared to the 10s, in the Antarctic we are 11 days behind the 10s average, which sums up to 31 days, almost a month).
Compared to earlier decades this difference is even bigger:
April 6, 2019 vs. 00s: 42 days
April 6, 2019 vs. 90s: 50 days
April 6, 2019 vs. 80s: 59 days (almost two months)
So there is a big difference as there is less ice to melt in the Arctic this coming melting season (so less energy needed) and more ice to form in the Antarctic this coming freezing season (more freezing energy to be released). In addition you must also take the Albedo effect into account.

33
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: April 07, 2019, 08:27:20 AM »
~340k less than the previous record ... :o
...and still ten to eleven days ahead of any other year since 1979 (2018 had a slightly lower value on April 17)

34
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: April 06, 2019, 07:50:55 AM »
2019 is now 11 days in advance (April 16, 2018 had a lower value than extent yesterday). 2019 will probably keep its lowest position for the next days.

35
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: April 05, 2019, 09:06:19 AM »
The top losers of sea ice area (see gerontocrat's posting above) from March 20-April 3 are Okhotsk, Barents, Bering and Kara Seas. In relative numbers the decrease in sea ice area is highest in Bering, followed by St. Lawrence and Barents. Almost no change still in the central Arctic seas such as CAA, CAB and ESS.

36
Arctic sea ice / Re: Global sea ice area and extent data
« on: April 05, 2019, 07:56:22 AM »
A smaller increase (as Average) in Antarctic and a larger decrease (as average) in the Arctic today led to a new record low in global sea ice, as "announced" by several people here in this forum. Today it came true.

37
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: April 03, 2019, 08:37:26 AM »
2019 is now six days ahead (8.4.2016 had the same extent as 2.4.2019) and further extent losses are likely.

38
Science / Re: 2019 Mauna Loa CO2 levels
« on: April 02, 2019, 10:21:36 PM »
Week beginning on March 24, 2019:     411.32 ppm
Weekly value from 1 year ago:       409.90 ppm
Weekly value from 10 years ago:     389.31 ppm
At least this week has settled down (+ 1.42 ppm/y), due to some lower daily values (they are very scattered, compared to last years) in that week and a relatively high weekly value one year ago. The following week has been lower last year, so one should expect a higher yearly increase next week...

39
Very interesting article. Thanks for sharing this information with us.

40
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: April 02, 2019, 06:40:53 PM »
Based on minimums 1979-2018 and linear regression, I calculated probabilities to get minimum below 2012 in 2019-2035 (blue dots). Also cumulative probability (red dots) and probability to get minimum below 2012 first time that year (green dots).
From linear regression of the Sep averages an area of 3,50 M km² will be reached around 2030.

41
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: April 01, 2019, 08:42:08 AM »
If there were no further drop in the next days (what I do not expect), 2019 will keep the record low position at least until April 5.

42
Arctic sea ice / Re: The 2019 melting season
« on: March 31, 2019, 09:24:06 PM »
You may need to do a little math of your own though, but you should come to the same conclusions.

Strangely enough I've done a bit of maths (as we call the subject here in the once Great Britain), and a fair bit of programming too.

Perhaps you wouldn't mind enlightening me further concerning how you came to your particular conclusions? Methodology as well as raw data would be helpful, for example.

The raw data is in the previous link.  I have plotted at the recent melt compared to the annual maximum, minimum, previous season ice growth, and change in ice maximum from the previous season.  No correlation exists in any of the comparisons.  Early season melt is no indication of what is to come later in the season.

Please refer to my posting last year where I plotted the average monthly losses vs. the JAXA minimum and found almost no correlation (the best with R² = 0.79 is valid for July; but July is the month with the biggest losses...)
https://forum.arctic-sea-ice.net/index.php/topic,2285.msg157248.html#msg157248

43
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: March 31, 2019, 06:01:05 PM »
Evaluating the individual seas between March 13 and March 31 the biggest contributors are Barents, Okhotsk, St. Lawrence, Kara and Baffin, of which St. Lawrence showed the biggest relative decrease (63 %). All of these seas are quite "southern" and - except for Kara - not part of the "inner seas" close to CAB.

44
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: March 31, 2019, 08:30:19 AM »
This drop is higher and steeper than I thought it would be. If there were no further change in the next days (what I do not expect), 2019 will keep the record low position at least until April 3.

45
Arctic sea ice / Re: The 2019 melting season
« on: March 30, 2019, 09:10:46 AM »
...and the ice in Kara Sea also does not look very healthy (see Aluminium's animation above)

46
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: March 30, 2019, 09:08:56 AM »
Oh, oh,...
Another little drop below 13.55 M km² tomorrow will push 2019 to the lowest extent ever measured on that date. Not good!

47
Science / Re: 2019 Mauna Loa CO2 levels
« on: March 24, 2019, 09:55:38 PM »
Very worrisome.
You just need to look at the long term linear trend which increased by about 0.8 ppm/month in the last 12 years. Where will this end??

48
Arctic sea ice / Re: The 2019 melting season
« on: March 24, 2019, 09:48:22 PM »
Thanks for that animation. It looks like Fram export has been really active for a while now. Anyway, when I recall correctly from one of Wipneus' latest posting, Fram export is normal compared to long term averages. Is that correct?

49
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: March 24, 2019, 08:13:26 AM »
Two or three further days losses of this size would push 2019 to #4 in that ranking list.
Let's see how Bering Sea will behave the next days. Its change will probably make the difference...

50
Antarctica / Re: Thwaites Glacier Discussion
« on: March 21, 2019, 10:27:22 PM »
One consequence of this breakout is visible on the latest EOSDIS picture.
After nearly half a month of mostly complete cloud coverage, a glimpse between the clouds reveals that open water has almost reached the calving front of the Thwaites glacier (it is approx. parallel to the grey line ("2010 grounding line")) and marked in pale magenta.
I wonder whether the next days will allow a deeper look onto what happened there and whether the calving front is really affected.
See attached picture.

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