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helorime

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Re: IJIS/JAXA
« Reply #1050 on: March 21, 2015, 08:39:14 PM »
Quote
Do you have to read all of that? Of course not! I assume you live in a somewhat free country and can do what you want. Only if you were curious about what was displayed in the plot, you would naturally proceed to read the entire sentence.

I see that you do not understand my comment.  That's ok. Peter Ellis likely has it right.  Your graph appears to be of previous year's sea-ice extent differences from 2015 by calendar date.
Any sufficiently advanced technology is indistinguishable from magic.

viddaloo

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Re: IJIS/JAXA
« Reply #1051 on: March 21, 2015, 08:49:40 PM »
Your graph appears to be of previous year's sea-ice extent differences from 2015 by calendar date.
All of that's already in the chart title, that's why I don't understand why you ask other people about it instead of just reading it. Maybe there is a cultural code here that I just do not get. From a plot developer perspective it makes no difference what is written in the title if people do not read it.
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helorime

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Re: IJIS/JAXA
« Reply #1052 on: March 21, 2015, 09:01:35 PM »
Is there a chart title other than this?

Quote
2% of max extent gone. Lowest as of February 27th, but with a Friday margin of just 68 km2 back to 2006

That title says nothing about graphing the difference from the 2015 value.  It implies that it should be of % difference from maximum extent, though it clearly isn't.  I am only saying this to be helpful here.  Knowing what the graph is of makes it more interesting and informative.
Any sufficiently advanced technology is indistinguishable from magic.

viddaloo

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Re: IJIS/JAXA
« Reply #1053 on: March 21, 2015, 09:16:47 PM »
helorime, I think those are splendid ideals and looking forward to seeing your plots.

PS: To your question pertaining to the existence of other chart titles than the one featured in the chart, I am sorry that again I will have to disappoint you. There are none in the chart other than the one you can see in the chart. I trust you when you say you are neither dazed nor confused, but now you've made me both dazed and confused. I would say 99% you are making an early April Fool's joke, and that definitely *would* be a cultural thing. In my country we wait till the day is here! ;)
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seaicesailor

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Re: IJIS/JAXA
« Reply #1054 on: March 21, 2015, 09:37:42 PM »
Viddaloo, sometimes you sound as if the forum was yours.
It would be nice if you state what the y-axis is in your plots. It is customary, to say the least

viddaloo

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Re: IJIS/JAXA
« Reply #1055 on: March 21, 2015, 09:52:05 PM »
Viddaloo, sometimes you sound as if the forum was yours.
It would be nice if you state what the y-axis is in your plots. It is customary, to say the least
The Y–axis is margin to 2015 extent in km², as explained in the chart title:

Quote
2% of 2015 max extent gone. Lowest as of February 27th, but with a Friday
margin of just 68k km² back to 2006.

Back to the ice: If 2015 Arctic sea ice extent as measured by IJIS/JAXA can stay below 13774012 km² today and 13774868 tomorrow, 2015 will have been lowest in Arctic sea ice extent as measured by IJIS/JAXA for 24 days at the expense of the low 2006 period in March–April, which will then be reduced to a 22 day period of being lowest in Arctic sea ice extent as measured by IJIS/JAXA. Odds are the only other continually lowest period on this side of Solstice, the 2006 row from Apr 28 to May 25, will also be sliced, making the present record series of Feb–Mar lowest Arctic sea ice extent measurements by IJIS/JAXA the longest in the first half of the year.
« Last Edit: March 21, 2015, 10:26:29 PM by viddaloo »
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viddaloo

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Re: IJIS/JAXA
« Reply #1056 on: March 21, 2015, 11:03:28 PM »
How 'bout that? No other year being continually lowest for more days in a row in the entire first 6 months of the year, and we will know in just 6 1/2 hours. Do you think it's possible? The only thing we need to do is lose extent or at least gain less than 68869 km².

Slicing the late Apr to late May line of 2006 low days will be a walk in the park.
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wili

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Re: IJIS/JAXA
« Reply #1057 on: March 22, 2015, 03:22:21 AM »
"Other graphs from viddaloo are more confusing."

I have nothing against vid, but I don't bother trying to understand his graphs. (And I do in fact understand most graphs that I've come across on this and other sites.) If he thinks they are illuminating something to someone...well, they aren't to me, or apparently to many other bright people here. Of course, if someone gets a kick out of posting obscure graphs on relatively obscure site, I guess they're free to do so.
"A force de chercher de bonnes raisons, on en trouve; on les dit; et après on y tient, non pas tant parce qu'elles sont bonnes que pour ne pas se démentir." Choderlos de Laclos "You struggle to come up with some valid reasons, then cling to them, not because they're good, but just to not back down."

Espen

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Re: IJIS/JAXA
« Reply #1058 on: March 22, 2015, 05:25:29 AM »
IJIS:

13,738,377 km2(March 21, 2015)up 32,378 km2 from previous.
Have a ice day!

Sleepy

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Re: IJIS/JAXA
« Reply #1059 on: March 22, 2015, 08:59:18 AM »
I feel that the arguing should be spared for our happy positive green BAU people and the politicians they vote for.

At least for the Swedish deniers (who might read on this obscure(?) forum since they have used Jim Pettit's graphs in the past), I might be useful to clear up one graph a bit just to clarify the big picture.  ;)

Espen

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Re: IJIS/JAXA
« Reply #1060 on: March 22, 2015, 09:37:49 AM »
IJIS:

Unless 2015 drops 5,962 km2 or more tomorrow, 2006 will take over the lowest measured for date.
Have a ice day!

viddaloo

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Re: IJIS/JAXA
« Reply #1061 on: March 22, 2015, 10:49:28 AM »
IJIS:

Unless 2015 drops 5,962 km2 or more tomorrow, 2006 will take over the lowest measured for date.

I'd say it's definitely doable. It's pretty much down to the Bering Strait, IMO.
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Jim Pettit

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Re: IJIS/JAXA
« Reply #1062 on: March 22, 2015, 01:43:22 PM »
IJIS:

Unless 2015 drops 5,962 km2 or more tomorrow, 2006 will take over the lowest measured for date.

Indeed. JAXA extent has increase by about 79k km2 over the past two weeks, whereas it decreased by 207k over the two weeks prior to that. Thanks to that growth, it today sits just 204k (1.46%) below February's 2015 max-to-date.

(Having said that, barring some final-week burst of intense ice-making, 2015 has pretty much locked up first place for the March monthly average.)

Shared Humanity

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Re: IJIS/JAXA
« Reply #1063 on: March 22, 2015, 01:47:18 PM »
Is there a chart title other than this?

Quote
2% of max extent gone. Lowest as of February 27th, but with a Friday margin of just 68 km2 back to 2006

That title says nothing about graphing the difference from the 2015 value.  It implies that it should be of % difference from maximum extent, though it clearly isn't.  I am only saying this to be helpful here.  Knowing what the graph is of makes it more interesting and informative.

Just thought I would let you know that I find the title of this graph confusing as well. Perhaps viddaloo needs assistance labeling axis on charts.
« Last Edit: March 22, 2015, 01:52:19 PM by Shared Humanity »

Shared Humanity

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Re: IJIS/JAXA
« Reply #1064 on: March 22, 2015, 01:50:37 PM »
How 'bout that? No other year being continually lowest for more days in a row in the entire first 6 months of the year, and we will know in just 6 1/2 hours. Do you think it's possible?

Even more important, should we care?

viddaloo

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Re: IJIS/JAXA
« Reply #1065 on: March 22, 2015, 01:54:32 PM »
Indeed. JAXA extent has increase by about 79k km2 over the past two weeks, whereas it decreased by 207k over the two weeks prior to that. Thanks to that growth, it today sits just 204k (1.46%) below February's 2015 max-to-date.

(Having said that, barring some final-week burst of intense ice-making, 2015 has pretty much locked up first place for the March monthly average.)
But not for March net melt! 2015 is only 8th highest to date in March net melt.
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Jim Pettit

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Re: IJIS/JAXA
« Reply #1066 on: March 22, 2015, 01:57:39 PM »
Indeed. JAXA extent has increase by about 79k km2 over the past two weeks, whereas it decreased by 207k over the two weeks prior to that. Thanks to that growth, it today sits just 204k (1.46%) below February's 2015 max-to-date.

(Having said that, barring some final-week burst of intense ice-making, 2015 has pretty much locked up first place for the March monthly average.)
But not for March net melt! 2015 is only 8th highest to date in March net melt.

True. But extent entered the month already in first place. With that head start, it neither needed to melt as much to stay in first, nor was there as much disappearable ice available.

Crazy year--and it's still only March.

viddaloo

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Re: IJIS/JAXA
« Reply #1067 on: March 22, 2015, 02:18:46 PM »
Yup, and that 23–day lowest is to date one of the most astonishing features of 2015 sea ice, for us happy few who care about that sort of thing.

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viddaloo

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Re: IJIS/JAXA
« Reply #1068 on: March 22, 2015, 03:51:10 PM »
I'm happy to say I now join the ranks of Confused Humanity. In my case, I was confused about the end of the year. Some sort of New Year's Eve bug. In any case, 2010 was lowest for 15 days at the end, if you allow January 1st 2011 to be counted as 2010.

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Peter Ellis

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Re: IJIS/JAXA
« Reply #1069 on: March 22, 2015, 11:11:44 PM »
Is there a chart title other than this?

Quote
2% of max extent gone. Lowest as of February 27th, but with a Friday margin of just 68 km2 back to 2006

That title says nothing about graphing the difference from the 2015 value.  {...}

PS: To your question pertaining to the existence of other chart titles than the one featured in the chart, I am sorry that again I will have to disappoint you. There are none in the chart other than the one you can see in the chart.

That's not a title.  A title consists of a few words concisely describing what is being graphed, e.g. "Daily sea ice anomalies relative to 2015 values".

Your graph has no title, however you've taken two sentences that describe the findings (poorly and confusingly) and stuck them in the title field instead of in the main text of the post where they belong.  Rest assured that if you produced such a graph for a class at any university I've taught in, you'd fail.

When called out on this and similar failings, the least you could do is have the grace to learn from what people are saying, rather than being patronising and unpleasant towards them.

jbatteen

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Re: IJIS/JAXA
« Reply #1070 on: March 23, 2015, 03:17:42 AM »
I've been looking for a while but I can't find it.  Is the ignore function implemented on the forum anywhere?  This thread would be a lot more readable without the mysterious graphs.  I can't figure out what they mean either and they contribute nothing to my understanding of the ice.  They take a long time to load on my rural DSL connection too.

OSweetMrMath

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Re: IJIS/JAXA
« Reply #1071 on: March 23, 2015, 03:51:40 AM »
jbatteen,
If you view your Profile, there's an option for "Buddies/Ignore List" under Modify Profile. Not the most obvious place, true.

Espen

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Re: IJIS/JAXA
« Reply #1072 on: March 23, 2015, 05:23:54 AM »
IJIS:

13,804,766 km2(March 22, 2015)up 66,389 km2 from previous, 2nd lowest after 2006 (-72,351 km2)
Have a ice day!

Lord M Vader

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Re: IJIS/JAXA
« Reply #1073 on: March 23, 2015, 08:18:35 AM »
Well, this might be a thriller as the sea ice have about 48 hours more to grow before more unfavorable conditions are taking over and probably slow down any sea ice growth! :-X

What number did IJIS produce for February 15? If my memory is correct we are about 130 000 km2 behind February 15 in extent...

//LMV

Jim Pettit

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Re: IJIS/JAXA
« Reply #1074 on: March 23, 2015, 11:55:11 AM »
Well, this might be a thriller as the sea ice have about 48 hours more to grow before more unfavorable conditions are taking over and probably slow down any sea ice growth! :-X

What number did IJIS produce for February 15? If my memory is correct we are about 130 000 km2 behind February 15 in extent...

//LMV

137,294k km2, to be precise.

That extent rise is the largest one-day increase since 09 February, and the fourth-largest since 16 January. As Espen noted, 2015 is now in 2nd place for the day, ending a consecutive 23-day stretch in first place. IOW, yesterday's increase is kind of a big deal for those of us who remain obsessed with the daily up and down of Arctic sea ice.

Ned W

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Re: IJIS/JAXA
« Reply #1075 on: March 23, 2015, 01:23:50 PM »
It'd be kind of nifty if IJIS happened to gain exactly those 137,294k km2 before turning back downward. 

Then 2015 would set not two, but three records:  lowest max, earliest max, and latest max.
 

viddaloo

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Re: IJIS/JAXA
« Reply #1076 on: March 23, 2015, 02:51:39 PM »
That extent rise is the largest one-day increase since 09 February, and the fourth-largest since 16 January. As Espen noted, 2015 is now in 2nd place for the day, ending a consecutive 23-day stretch in first place. IOW, yesterday's increase is kind of a big deal for those of us who remain obsessed with the daily up and down of Arctic sea ice.

Yesterday's increase can be considered a random deviation from the current trend, can it not? IMO the ocean heat content has proven to us that it's more than capable of serving a 23–day stretch of all–time lows, and the ocean is wearing the trousers here, right? Daily sea ice totals are merely a symptom or consequence.

2011 won last week's melt contest overwhelmingly, first by actually melting ice, which 2015 didn't, and second by melting over 209 thousand square kilometers of it. I'll say now that if this week isn't won equally overwhelmingly by 2015 — when 2011 *gained* 41847 km² — then 2015 will likely finish 4th lowest or higher in September. If we can keep ahead of 2011 losses we may be 3rd or lower.
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Siffy

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Re: IJIS/JAXA
« Reply #1077 on: March 23, 2015, 03:23:36 PM »
That extent rise is the largest one-day increase since 09 February, and the fourth-largest since 16 January. As Espen noted, 2015 is now in 2nd place for the day, ending a consecutive 23-day stretch in first place. IOW, yesterday's increase is kind of a big deal for those of us who remain obsessed with the daily up and down of Arctic sea ice.

Yesterday's increase can be considered a random deviation from the current trend, can it not? IMO the ocean heat content has proven to us that it's more than capable of serving a 23–day stretch of all–time lows, and the ocean is wearing the trousers here, right? Daily sea ice totals are merely a symptom or consequence.

2011 won last week's melt contest overwhelmingly, first by actually melting ice, which 2015 didn't, and second by melting over 209 thousand square kilometers of it. I'll say now that if this week isn't won equally overwhelmingly by 2015 — when 2011 *gained* 41847 km² — then 2015 will likely finish 4th lowest or higher in September. If we can keep ahead of 2011 losses we may be 3rd or lower.

No weather has always dominated, ocean temperature and air temperature merely set the base line for weather to modify, from a year to year basis weather is what effects the outcome of iceloss/gain.

I don't know how to put this gently but your way of guessing at the end of year melt conditions is nonsensical.

Using your method you will project that 2012 couldn't happen because it's not setting records in the early part of the melt season. You're completely ignoring the actual system in place and just comparing against previous years. This is why you were projecting continued melt lost loss last week and other posters stated that there would be ice gain towards a possible new maximum because they were watching the weather forecasts. You predicted the complete opposite of what happened.
« Last Edit: March 23, 2015, 04:32:41 PM by Siffy »

Nightvid Cole

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Re: IJIS/JAXA
« Reply #1078 on: March 23, 2015, 04:33:43 PM »
It'd be kind of nifty if IJIS happened to gain exactly those 137,294k km2 before turning back downward. 

Then 2015 would set not two, but three records:  lowest max, earliest max, and latest max.

I highly doubt it, and it looks like this increase is spurious, since it coincides with storm-related "false ice" near Nova Scotia...

Espen

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Re: IJIS/JAXA
« Reply #1079 on: March 24, 2015, 05:43:43 AM »
IJIS:

13,834,885 km2(March 23, 2015)up 30,119 km2 from previous and 2nd lowest for the date.
Have a ice day!

Jim Pettit

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Re: IJIS/JAXA
« Reply #1080 on: March 24, 2015, 11:42:00 AM »
IJIS:

13,834,885 km2(March 23, 2015)up 30,119 km2 from previous and 2nd lowest for the date.

Yep. Just 107k km2 below the 15 February maximum-to-date--and note that extent has increased 129k over the past three days (the largest three-day increase since the second week of February)...

themgt

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Re: IJIS/JAXA
« Reply #1081 on: March 24, 2015, 01:18:31 PM »
2011 won last week's melt contest overwhelmingly, first by actually melting ice, which 2015 didn't, and second by melting over 209 thousand square kilometers of it. I'll say now that if this week isn't won equally overwhelmingly by 2015 — when 2011 *gained* 41847 km² — then 2015 will likely finish 4th lowest or higher in September. If we can keep ahead of 2011 losses we may be 3rd or lower.

This is becoming like some numerological cargo cult. Please take a step back and try to hear the criticism of many others in this forum that these increasingly arbitrary comparisons and highly specific, unsupportable predictions are unhelpful and distracting to the overall discussion.

DavidR

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Re: IJIS/JAXA
« Reply #1082 on: March 24, 2015, 01:26:09 PM »
IJIS:

13,834,885 km2(March 23, 2015)up 30,119 km2 from previous and 2nd lowest for the date.

Yep. Just 107k km2 below the 15 February maximum-to-date--and note that extent has increased 129k over the past three days (the largest three-day increase since the second week of February)...
I've just noticed that the NSIDC 5 day average shows a strong correlation between the duration of the period when the extent is within 200 K km^2 of the peak and the size of the subsequent melt.

http://forum.arctic-sea-ice.net/index.php/topic,1149.msg48538.html#msg48538

I wonder if the same applies to IJIS/JAXA?
Toto, I've a feeling we're not in Kansas anymore

Ned W

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Re: IJIS/JAXA
« Reply #1083 on: March 24, 2015, 01:57:07 PM »
It'd be kind of nifty if IJIS happened to gain exactly those 137,294k km2 before turning back downward. 

Then 2015 would set not two, but three records:  lowest max, earliest max, and latest max.

I highly doubt it, and it looks like this increase is spurious, since it coincides with storm-related "false ice" near Nova Scotia...

What's false about the ice near Nova Scotia?  If you're talking about ice in the Gulf of St Lawrence, and out around the eastern side of Cape Breton, it's quite real.  Here's a MODIS image from a couple of days ago:



I also highly doubt that IJIS will exactly tie its February max, but just because the odds of exactly hitting one particular number, to the nearest 1km2, are quite low.

But the increase is not "spurious", it's happened for three days now.  Is it likely to continue?  I dunno, most people here are probably better at interpreting the weather forecast than I am.

In a simplistic statistical sense, 2 of the past 12 years have seen enough increase in ice during the coming week to put us back above the February max.  So ignoring the weather, the odds are about 1 in 6.  Not likely, but not impossible.

Ned W

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Re: IJIS/JAXA
« Reply #1084 on: March 24, 2015, 02:06:36 PM »
Quote
I've just noticed that the NSIDC 5 day average shows a strong correlation between the duration of the period when the extent is within 200 K km^2 of the peak and the size of the subsequent melt.

http://forum.arctic-sea-ice.net/index.php/topic,1149.msg48538.html#msg48538

I wonder if the same applies to IJIS/JAXA?

What do you mean as a "strong" correlation?  It's based on a small number of points (less than 10) and the r2 value is about 0.4.  Even ignoring the issues that Nightvid Cole pointed out in the other thread, it's not significant even at alpha=0.05.

viddaloo

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Re: IJIS/JAXA
« Reply #1085 on: March 24, 2015, 02:23:39 PM »
At the risk of stepping on some very sore toes when comparing one year to another: 2015 started week 13 with a slightly smaller gain than 2011 and is thus now in the lead for week 13 melt (or lower gains).


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viddaloo

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Re: IJIS/JAXA
« Reply #1086 on: March 24, 2015, 02:52:44 PM »
You're completely ignoring the actual system in place and just comparing against previous years.
I don't think I am, so I'd have to say I disagree with you there. In science and elsewhere people often disagree. No big deal.

That said, I do admit I am comparing 2015 to 2011. Didn't know it was a capital crime?

This is why you were projecting continued melt lost loss last week and other posters stated that there would be ice gain towards a possible new maximum because they were watching the weather forecasts. You predicted the complete opposite of what happened.
What's a 'continued melt lost loss'? And where did I project that? I don't think I did, so you may have imagined this.

If my script estimated less gain and more melt based on some stated assumptions, it is obvious that the estimation will be wrong if those assumptions are wrong. If you think an estimate will — or should — always be correct, well, then that's where you should focus your efforts, IMO.
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DavidR

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Re: IJIS/JAXA
« Reply #1087 on: March 24, 2015, 03:00:29 PM »
Quote
I've just noticed that the NSIDC 5 day average shows a strong correlation between the duration of the period when the extent is within 200 K km^2 of the peak and the size of the subsequent melt.

http://forum.arctic-sea-ice.net/index.php/topic,1149.msg48538.html#msg48538

I wonder if the same applies to IJIS/JAXA?


What do you mean as a "strong" correlation?  It's based on a small number of points (less than 10) and the r2 value is about 0.4.  Even ignoring the issues that Nightvid Cole pointed out in the other thread, it's not significant even at alpha=0.05.

I have to  admit to just eyeballing it,  however its quite clear when  you  plot the points.  My data set only goes back to 2006 so perhaps someone with a longer data set could check it out.
I also checked NSIDC at 300K range rather than 200 and CT Area at 200K and they  all point to a minimum about 1/3 of the way between 2012 and 2007. 

If it  shows for IJIS/Jaxa that would suggest that there may  be something in it.

Given we haven't seen anything else with a good correlation between the max and the min we just have to keep trying.
Toto, I've a feeling we're not in Kansas anymore

seaicesailor

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Re: IJIS/JAXA
« Reply #1088 on: March 24, 2015, 04:37:35 PM »
Quote
I've just noticed that the NSIDC 5 day average shows a strong correlation between the duration of the period when the extent is within 200 K km^2 of the peak and the size of the subsequent melt.


What do you mean as a "strong" correlation?  It's based on a small number of points (less than 10) and the r2 value is about 0.4.  Even ignoring the issues that Nightvid Cole pointed out in the other thread, it's not significant even at alpha=0.05.

Given we haven't seen anything else with a good correlation between the max and the min we just have to keep trying.

Actually there might be something real behind your (weak) correlation. If in March we have positive arctic oscillation with atlantic-side storms that push ice out toward Fram and Barents, extent will be maintained or even increases. Then if more favorable conditions emerge in April - June, spread ice would be easier to melt. A pretty weak physical explanation but who knows :)

Nightvid Cole

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Re: IJIS/JAXA
« Reply #1089 on: March 24, 2015, 08:19:47 PM »
It'd be kind of nifty if IJIS happened to gain exactly those 137,294k km2 before turning back downward. 

Then 2015 would set not two, but three records:  lowest max, earliest max, and latest max.

I highly doubt it, and it looks like this increase is spurious, since it coincides with storm-related "false ice" near Nova Scotia...

What's false about the ice near Nova Scotia?  If you're talking about ice in the Gulf of St Lawrence, and out around the eastern side of Cape Breton, it's quite real.  Here's a MODIS image from a couple of days ago:



I also highly doubt that IJIS will exactly tie its February max, but just because the odds of exactly hitting one particular number, to the nearest 1km2, are quite low.

But the increase is not "spurious", it's happened for three days now.  Is it likely to continue?  I dunno, most people here are probably better at interpreting the weather forecast than I am.

In a simplistic statistical sense, 2 of the past 12 years have seen enough increase in ice during the coming week to put us back above the February max.  So ignoring the weather, the odds are about 1 in 6.  Not likely, but not impossible.

Actually the clouds near the East edge of that image appeared to be picked up by the sensor as ice, not just the actual ice. But now that we have had yet another day of increase I suspect the impact of that may have been fairly small.

Lord M Vader

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Re: IJIS/JAXA
« Reply #1090 on: March 24, 2015, 08:28:07 PM »
I think tomorrow will be a very important day! If JAXA doesn't blow the Mad Max we'll be able to call the max definitively as more hostile conditions are underway which will limit ice growth for a couple of days before a more favorable pattern emerge again..

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Espen

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Re: IJIS/JAXA
« Reply #1091 on: March 25, 2015, 06:04:58 AM »
IJIS:

13,833,407 km2(March 24, 2015)down 1,478 km2 from previous.
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Espen

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Re: IJIS/JAXA
« Reply #1092 on: March 26, 2015, 05:55:25 AM »
IJIS:

13,854,379 km2(March 25, 2015)up 20,972 km2 from previous, and almost 3rd for the date.
Have a ice day!

plg

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Re: IJIS/JAXA
« Reply #1093 on: March 26, 2015, 06:44:37 AM »
Interesting. From being the contender for earliest maximum, IJIS now may become the latest maximum: currently only 87681 from the Feb 15 value. Only 2010 peaked later, on March 31. Second latest is/was 2003, on March 21.
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Re: IJIS/JAXA
« Reply #1094 on: March 26, 2015, 09:19:11 AM »
The dipole anomaly spreads the ice out.  So don't be surprised if drops stop.

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crandles

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Re: IJIS/JAXA
« Reply #1095 on: March 26, 2015, 02:46:43 PM »


I have to  admit to just eyeballing it,  however its quite clear when  you  plot the points.  My data set only goes back to 2006 so perhaps someone with a longer data set could check it out.
I also checked NSIDC at 300K range rather than 200 and CT Area at 200K and they  all point to a minimum about 1/3 of the way between 2012 and 2007. 


Using 9 years 2006 to 2014 I get correlation coefficient of 0.718
Using 27 year 1988 to 2014 I get correlation coefficient of -0.02

So it isn't looking good.

Full Duration   Duration   Max-min   Min
76   15   9.148   7.1264
69   19   8.7946   6.9068
76   16   10.1404   6.0364
95   35   9.299   6.3018
92   58   8.3504   7.2088
78   21   9.8024   6.1846
89   36   8.7636   6.9608
94   58   9.331   6.0044
73   21   8.2348   7.191
87   35   9.0062   6.6274
60   10   9.6472   6.3516
99   34   9.8248   5.7574
75   20   9.4604   5.9784
81   24   9.0696   6.6026
79   32   9.9382   5.638
91   32   9.588   6.0072
74   27   9.422   5.7936
76   17   9.6336   5.3186
74   10   8.9086   5.774
76   27   10.6102   4.1544
88   34   10.7106   4.5856
88   24   10.0162   5.1196
96   32   10.6684   4.615
94   39   10.3224   4.3442
95   33   11.9078   3.3866
82   25   10.1126   5.0546
84   12   9.936   5.0284
      
Correlations      
27 years   -0.020099   -0.018116
9 years   0.718128   -0.720108
« Last Edit: March 26, 2015, 03:12:57 PM by crandles »

crandles

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Re: IJIS/JAXA
« Reply #1096 on: March 26, 2015, 03:11:56 PM »
Correlations with full durations      
27 years   0.2897185737   -0.3143055506
9 years   0.6501882107   -0.5549465041

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Re: IJIS/JAXA
« Reply #1097 on: March 26, 2015, 08:53:44 PM »
Interesting. From being the contender for earliest maximum, IJIS now may become the latest maximum: currently only 87681 from the Feb 15 value. Only 2010 peaked later, on March 31. Second latest is/was 2003, on March 21.

I'm still holding out hope for the idea that we'll exactly tie the Feb 15 value, and do it after March 31, thus pulling off a triple record (lowest, earliest, and latest maximum) simultaneously.

viddaloo

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Re: IJIS/JAXA
« Reply #1098 on: March 26, 2015, 08:59:07 PM »
I'm still holding out hope for the idea that we'll exactly tie the Feb 15 value, and do it after March 31, thus pulling off a triple record (lowest, earliest, and latest maximum) simultaneously.

Yup, and equally fun & impossible would be a total disappearance of all Arctic sea ice on April 1st only for the March 31st volume, extent etc to be put back on the 2nd. I won't hold my breath, but the Arctic *is* full of surprises.
[]

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Re: IJIS/JAXA
« Reply #1099 on: March 26, 2015, 09:35:04 PM »
Correlations with full durations      
27 years   0.2897185737   -0.3143055506
9 years   0.6501882107   -0.5549465041
Thanks, the hypothesis is not looking so good on those figures.  Still I'll keep an eye on it and see how the year develops. 
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