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Messages - Deeenngee

Pages: [1] 2
1
Arctic sea ice / Re: IJIS
« on: September 28, 2017, 05:29:40 PM »
Thanks Espen, you've put in an epic shift and provided a generous service to the rest of us.

2
Arctic sea ice / Re: IJIS
« on: September 19, 2017, 09:07:08 AM »
Cross-posting from the melting season thread.

(I think I might call this a running back graph for any NFL fans out there)

I really like that graph.  Very nice design.

(Thank you, that's good of you. Style-wise I've learnt a lot from Tamino over at Open Mind and all who advocate more minimalist design.)

3
Arctic sea ice / Re: IJIS
« on: September 17, 2017, 10:32:19 PM »
Cross-posting from the melting season thread.

(I think I might call this a running back graph for any NFL fans out there)

4
Arctic sea ice / Re: The 2017 melting season
« on: September 17, 2017, 10:28:55 PM »
Probably my final 2017 descent to the min graph update. Probably.

5
Arctic sea ice / Re: The 2017 melting season
« on: September 10, 2017, 11:07:10 PM »
Another update of my descent to the min chart, as we still seem to be descending....

6
Arctic sea ice / Re: The 2017 melting season
« on: September 04, 2017, 11:52:02 PM »
An updated descent to the min chart - 2017's path vs other years' minima.

7
Arctic sea ice / Re: IJIS
« on: August 27, 2017, 10:52:39 PM »
Updated comparison of 2017 vs previous years' minima here. It looks instinctively to me like a collision course with 2008, 2011 or 2015, but really, who knows...?

8
Arctic sea ice / Re: IJIS
« on: August 14, 2017, 03:37:08 PM »
Cross-posting from the melt season thread, an update of my chart showing IJIS in Aug-Sept and placement of each year's minimum date.

9
Arctic sea ice / Re: The 2017 melting season
« on: August 14, 2017, 03:33:48 PM »
Updated chart: descent to the min, 2017 vs other years

10
Arctic sea ice / Re: The 2017 melting season
« on: August 02, 2017, 10:17:17 PM »
Here's my minimum extent (IJIS) chart that's equivalent to the one I put up for the maximum, i.e. picking out the moment of minimum extent for each year since 1990.

For this first one I've kept the lines showing for each year, just so you can see that I haven't just plotted each year's minimum at some random location! I didn't do this by eye of course; on the IJIS datasheet it's easy, using conditional formatting, to highlight the lowest number for each column (year). This shows you the day number (i.e. date) of the minimum, which is then fairly easy to find on each line. Then right click, format data point, marker options etc etc.

What striking is how bunched the minimum dates are across the years, compared to the maximum (2nd chart below). Any ideas why, anyone?

And here's 2017 appearing, audience left / stage right....

11
Arctic sea ice / Re: The 2017 melting season
« on: August 02, 2017, 12:18:27 AM »
End of the month, so some updates of my charty-farty creations.

a. 2017 June-July vs 10yr rolling averages for June-July (the psychedelic toothpaste one)

b. 2017 May-July daily extent vs. 2010s average (i.e. 2010-2016) for each day.

c. Cumulative days in the bottom 3.

Combined, these help to emphasise that 2017 remains a low extent year despite some pretty unspectacular melt conditions, as discussed above.

12
Arctic sea ice / Re: IJIS
« on: July 23, 2017, 11:17:50 PM »
Some chartistic updates.
First, centred 7 day averages of daily extent change. 2017 is showing a charming sinusoidal shape, and is currently bang on the 2007-16 average.

Next, the same thing but with 2012 as well. The scale of the June 2012 extent drop and the GAC drop are plainly visible.

Then, 2017 daily extent change compared with the average extent change for the same day during 2007-16. It's just a different way to look at how the season is progressing.

Finally, the more conventional day by day chart with the historical range and decadal averages.

(I've also done an equivalent minimum chart to the one I posted a few times for the maximum, showing the timing and km2 of previous years. I'll post that around August 1st.)

13
Arctic sea ice / Re: IJIS
« on: July 14, 2017, 04:25:49 PM »
Perhaps Hyperion could take heart in previous triple century increases! I see one in October 2006 and one in October 2007...

14
Arctic sea ice / Re: IJIS
« on: July 13, 2017, 10:38:37 PM »
I've had a go at charting day-to-day change data and thought I'd share (apologies if someone here has done this before for IJIS data).

The first one is pretty self explanatory: day-to-day change from day 152-255 (June 1st to Sept 12th in a leap year); 2017 vs the average for 2007-16. It's interesting but a bit noisy - a bit like watching a game of Pong in 'crazy' mode.

So the second one smooooths things out, using 7-day centred averages, e.g. day 200 is the average of days 197-203.

It shows clearly how 2017 compares with the 2007-16 average for the each 7 day period: early to mid-June running ahead, then back on track, then lagging behind since the start of July.

15
The rest / Re: The Trump Presidency (was "Presidential Poll")
« on: July 07, 2017, 12:26:02 PM »
Correction - I'd accidentally filled in August. I don't expect much change by then though!

16
The rest / Re: The Trump Presidency (was "Presidential Poll")
« on: July 07, 2017, 12:22:42 PM »
An update on polling. Data from http://www.presidency.ucsb.edu/data/popularity.php?pres=45&sort=time&direct=DESC&Submit=DISPLAY

Trump can only dream of the 2nd quartile at the moment. I wonder if he cares, really?

17
As mentioned earlier. The PIOMAS values are from Wipneus' data & graphs website.

18
Arctic sea ice / Re: IJIS
« on: July 05, 2017, 07:56:24 PM »
What I find striking from Espen's extent chart is how there are six years that really close together at the moment, which then become quite widely spread out within 10 days or so. Perhaps we'll have a better idea around July 15th about 2017's trajectory, notwithstanding other metrics of course that most of us are probably watching. Or maybe not...

19
NedW, I've done a scatterplot of piomas summer months vs the jaxa daily minimum. The relationship is close-ish for July piomas, the coefficient is around 0.88. Not amazing for predictive purposes though; you'd want pretty wide error margins. I'll post a chart later if I get the chance.

20
Arctic sea ice / Re: IJIS
« on: July 02, 2017, 09:52:30 PM »
Thirdly, the psychedelic toothpaste comparison of 2017 and previous rolling 10 year averages.

(PS OT, what was your quiz team name, Gerontocrat?)

21
Arctic sea ice / Re: IJIS
« on: July 02, 2017, 09:34:47 PM »
A monthly update of the graphs best described as the IJIS graphs that I update on a monthly basis.
First, 2017 vs the range & decadal averages.
Second, cumulative days in the bottom 3 for 1990-2017.

22
Arctic sea ice / Re: IJIS
« on: June 11, 2017, 10:05:13 PM »
Also
- an updated shaded matrix of 1990-2017 rankings for May to June 10th
- and an update of 2017 extent compared to previous 10 year averages

23
Arctic sea ice / Re: IJIS
« on: June 11, 2017, 09:25:04 PM »
A couple of graphical updates coming up from me. Firstly, my IJIS ranking ramps (for want of a better description), which neatly shows the May pause as 2017 climbed out of the bottom 3, as well as the points at which other years (eg 2010 & 2011) starting to rack up bottom 3 placings.

24
The rest / Re: The Trump Presidency (was "Presidential Poll")
« on: June 04, 2017, 04:13:54 PM »
How do post-war US presidents compare in terms of their approval rating during their first term?http://www.presidency.ucsb.edu/data/popularity.php has data.

Here's teh Donald compared with his predecessors. (For simplicity's sake I've taken the value from the first opinion poll of each month).

25
Arctic sea ice / Re: IJIS
« on: April 25, 2017, 10:51:51 PM »
(this time with graph!)

26
Arctic sea ice / Re: IJIS
« on: April 25, 2017, 10:51:12 PM »
One more - this time, 10 year averages.

27
Arctic sea ice / Re: IJIS
« on: April 25, 2017, 09:47:31 PM »
An update of my chart showing cumulative days in the bottom 3 for each date. Also a grid view showing the numbers.

2017 has now overtaken 2006, 2007, 2011 and 2015. Unless there are a couple of extended plateaux, I'd be surprised if 2017 spends much time outside the bottom 3 to the end of May.

Finally, an update of my 2017 vs 1990-16 daily range chart, now shifted to April & May.

28
Arctic sea ice / Re: IJIS
« on: April 02, 2017, 10:27:32 PM »
My concluding chart for the max season.

29
Arctic sea ice / Re: IJIS
« on: March 28, 2017, 10:47:45 AM »
Very interesting Deeennggee

Really simple yet frightening graph there.

Soon wel just be talking about the sea.


Or for anyone on the other side of the pond, 1.4m sqkm = California + Oregon + Washington State + Idaho + Nevada

30
Arctic sea ice / Re: IJIS
« on: March 27, 2017, 11:07:14 PM »
"Let it go, let it go!!" Kind words indeed. I can only assume you've been surrounded by some very average graphs in the past.

Somethin' else here - IJIS & NSIDC extent anomalies, 2017 vs two different reference periods.

As my sense of scale often disappears when looking at maps of the Arctic: 1.4m sq km (the current variance from the 1990s average) is the same as the combined area of France, Switzerland, Germany, Luxembourg, the Netherlands, Belgium, Denmark and the UK.

31
Arctic sea ice / Re: IJIS
« on: March 23, 2017, 07:34:01 PM »
Here's my corrected plot of days in the bottom 3 for each year (lesson: more haste, less speed).
For each date I've calculated the actual ranking to be in the bottom 3; this is needed because of data gaps (eg late July-early August 2002), which throws all the other years' rankings by one place. So I've definitely identified the bottom 3 years for each date now. This gives the correct cumulative plot, attached. I've excluded years that by Dec 31st had accumulated fewer than 20 bottom 3 days for any date.

Thanks to all who responded to my first, rather excitable post on this one - you were sceptical in the proper sense of the word.

Looking at the next 10 days: 2005, 2006, 2007, 2015 and 2016 all have days that are currently 25th out of 27 (see excerpt of rankings attached from my .xls). In the likely event that 2017 extent remains in the bottom 3, its cumulative score will gain one each day, and one of those other years will lose one each time.

The inevitable question is "so what?" Does this (in March) really matter when it comes to the showdown - the summer minimum? I don't really know the answer to that, but my hunch is that it might say something about the overall condition of the ice.

And don't worry, I won't post overly regular updates of the chart! It could get a bit tedious. But maybe monthly... 


32
Arctic sea ice / Re: IJIS
« on: March 22, 2017, 04:09:40 PM »
Ah. Methodology flaw alert - thanks Oren. The COUNTIF was looking for days ranked 28th, 27th and 26th. And for dates we haven't had this year yet, they actually only go from 1 to 27.

I've redone it so it counts if a day is ranked 25th, 26th and 27th i.e. the previous 'bottom 3'. That means that 2006, 2007, 2011 and 2015 gain some bottom 3 days - so yes, by the end of their years they have more bottom 3s than 2017 at the moment. But not by much. As things stand,  2017 could well overtake those year by the end of April.

This needs some more work! Good to have friendly peer-reviewers.

I don't have an online graph repository - any suggestions? Google Drive?


 


33
Arctic sea ice / Re: IJIS
« on: March 22, 2017, 10:18:06 AM »
Again, but with an essential clarification in the title!

(The graph doesn't include years that don't feature a day in the bottom 3 for the date)

34
Arctic sea ice / Re: IJIS
« on: March 22, 2017, 10:14:06 AM »
As mentioned.

35
Arctic sea ice / Re: IJIS
« on: March 22, 2017, 09:14:46 AM »
Sorry, my explanation of daily rankings was a bit convoluted. To confirm, I'm ranking each year for each date of the year. So, all the January 1sts ranked, then all the January 2nds and so on.

The simplest expression is maybe 'bottom 3 days for each date'.

2017 has already had 77 of those. And indeed what i was saying is that only 2012 and 2016 had more bottom 3 days for each date over their entire year than 2017 has already had. 2012 racked them up during the summer, 2016 had them more spread out.

I'll do a cumulative plot later which should show it reasonably clearly.

36
Arctic sea ice / Re: IJIS
« on: March 21, 2017, 11:37:49 PM »
So far, 2017 has had 77 days ranked in the bottom 3 for each day's comparative ice extent over the 1990-2017 period, and 2 days not in the bottom 3.

This means 2017 has already overtaken every single year for days in the bottom 3 for that day, apart from 2012 and 2016.

By day 79, 2016 had 58 days in the bottom 3 for 1990-2017
By day 79, 2012 had 2 days in the bottom 3 for 1990-2017.

I don't usually do emoticons, but anyway:  :(


37
Arctic sea ice / Re: IJIS
« on: March 21, 2017, 05:38:42 PM »
Thanks Meirion and Bill F.  It would have helped if I'd labelled the X axis with 'day number' or something like that!

One can also have a version that shows the trajectory of each year - rather than the grey range - but it's very noisy. Although, as indicated in the blog comments, I've embraced the noise for artistic effect (inspired by Joy Division) over at the 'cafe' thread.

38
The rest / Re: Arctic Café
« on: March 20, 2017, 10:45:13 PM »
(Because a) I'd feel sheepish putting this in the main IJIS thread, b) I wanted somewhere to link to from the main blog, and c) this is a home for random offtopicness...)

The first in a likely short lived series, 'Arctic charts that resemble album covers', I give you my IJIS / Unknown Pleasures mashup.


39
Arctic sea ice / Re: IJIS
« on: March 18, 2017, 01:30:10 PM »
Weekly update of my 2017 vs 1990-2016 maxima chart.

40
Arctic sea ice / Re: IJIS
« on: March 10, 2017, 08:59:06 PM »
Here's my update, also with the late season rallying years that Jim P mentions. From top 2003, 2012, 2014, 2015.

41
Arctic sea ice / Re: IJIS
« on: March 09, 2017, 07:16:04 PM »
But it's kind of fun to have another moment in the year to speculate about. The max is in polar (haha) opposition to the minimum, and it marks the passing of one phase of the year to the other. Plus, there is a downward trend in the annual max, which is interesting in itself and part of the bigger story...

42
Arctic sea ice / Re: 2017 IJIS extent maximum prediction
« on: March 06, 2017, 10:13:08 PM »
As per before, but now going back to 1990. 14.0 looks to me like a coin flip, albeit based on eyeballing and absolutely nothing scientific, meteorological etc.

43
Arctic sea ice / Re: IJIS
« on: March 06, 2017, 09:55:37 PM »
An update of my '2017 vs the others' maximums' chart. I've extended it to go back to 1990.
As most of you probably know the 1980s dataset only has every-other-day readings, so there's a lot less confidence during that decade that each year's max was indeed the max.

44
Arctic sea ice / Re: IJIS
« on: March 04, 2017, 07:06:36 PM »
Bill
Thanks for that, and I enjoyed that post of yours that you linked to there. One of the first things I thought of when I produced the heat chart above was exactly that, about how it shows the paucity of the contractions argument when they find a recent day in April, usually, that is superficially similar to another April day in the dim and distant.
Incidentally, my use of the word 'concocted' earlier wasn't meant to imply some originality on my part ref my heat chart. 'Assembled' would probably have been a better verb to use.

45
Arctic sea ice / Re: IJIS
« on: March 01, 2017, 11:54:07 PM »
Another cheeky chart of IJIS extent data if I may.

Having ranked each day from 1990-2017 against its respective days (where 1 is the most ice for that day and 28 is the least), I counted the number of days that each year has in each rank (1 to 28). I then grouped them: top 5, 6-10, 19-23 and bottom 5 (24-28).

I shouldn't be surprised at the result, but plotting it out like this is still pretty staggering.

Between 1990-2003 there were only 17 days in total that are ranked in the bottom 10 (as in, least ice) for their respective days over the 1990-2017 period. And from 2011 to today, only 11 days ranked in their respective top 10 - and those were all in April 2012!

46
Arctic sea ice / Re: IJIS
« on: February 28, 2017, 10:50:19 PM »
As I'm in the mood for trying different visualisations, here's a thing I concocted as another way to look at IJIS data. The procedure:

Downloaded the daily extent data (1990-2017).

Used the RANK equation to rank each year - from 1 to 28 where 1 is the largest extent for any year on that day, and 28 is the least.

Then conditional formatting so that 1 is blue and 28 is red, and everything graded in between.

Then made the numbers invisible, pasted into powerpoint and squeezed it vertically.

Quite a pleasing effect, and moderately informative!

No idea how this will look when I press Post, but here goes....


47
Arctic sea ice / Re: IJIS
« on: February 27, 2017, 10:23:44 AM »
Looking at the 2003-2016 February and March IJIS data there are quite a lot of runs of 3 or 4 consecutive days of extent going down before the maximum has been reached.

There were runs of 5 consecutive days of decrease prior to the eventual max in 2009 and 2010.

2003 even had 8 consecutive days of decrease, losing 258k sq km in the process before it then went up again, gaining 277k sq km and hitting its maximum.

48
Arctic sea ice / Re: 2017 IJIS extent maximum prediction
« on: February 27, 2017, 12:10:16 AM »
Another update here.
Will extent follow the typical path for the 2010s, upwards until mid-March.
Or is it a case of 'Averages? Pah!' ?

49
Arctic sea ice / Re: IJIS
« on: February 27, 2017, 12:04:01 AM »
My weekly update, this time with the 'average for the 2010s' trajectory superimposed, which on its own suggests 14.0 might still be passed. Not that the Arctic seems bothered about averages this decade; certainly not he last 12 months. Anyway, make of it as you will...

50
Arctic sea ice / Re: 2017 IJIS extent maximum prediction
« on: February 20, 2017, 10:30:40 AM »
As mentioned a weekly update of my 2017 vs the rest maximum chart.
As we had a sharp uptick last week I've picked out 2005 for its impressive rollercoaster profile around the max. 

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