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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #200 on: February 25, 2018, 10:34:32 AM »
JAXA data for the 24th Fb. The average daily increases of 50 for the the five dys have switched to a decrease of 19k, and as pointed out already, means 2018 is in its lonely furrow again.
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Pmt111500

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Re: 2018 sea ice area and extent data
« Reply #201 on: February 25, 2018, 12:47:49 PM »
Wish the nullschool could incorporate the essential data to the graphs so I wouldn't have to cut and paste it so. It looks like north pole is almost 10 degrees warmer than home. It's of course happened once in a while before too, but it's anyway remarkable when it happens.

London's about the same as the pole, Paris a bit colder as is Split on the Mediterranean, Tokyo again almost the same, like is the tip of Antarctic Peninsula (this last one shouldn't surprise very much)
« Last Edit: February 25, 2018, 03:20:26 PM by Pmt111500 »
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Ice Shieldz

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Re: 2018 sea ice area and extent data
« Reply #202 on: February 25, 2018, 08:13:05 PM »
The elephant in the room here is of course that extent is lowest in core arctic seas and high in peripheral seas. Is anyone cumulatively plotting that and comparing it with previous years?

Interesting to see this trend reflected in the CAB itself. Perhaps the lift off of ice from Greenland is beginning to show up in CAB extent. Short of more crazy weather, which it seems we'll be seeing a bit of a reprieve from, the recent losses in CAB extent should be recovered relatively quickly.

Dharma Rupa

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Re: 2018 sea ice area and extent data
« Reply #203 on: February 25, 2018, 08:30:53 PM »
...Short of more crazy weather...

It isn't crazy weather.  It is clearly WACCy (wacky) weather.

If there wasn't a clear pattern emerging it would be crazy, but the pattern is getting clearer every year.  The heat reservoir of the ocean is filling up even as the land mass quickly sheds heat every Winter.


Ice Shieldz

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Re: 2018 sea ice area and extent data
« Reply #204 on: February 25, 2018, 08:38:35 PM »
Hmm i don't understand how WACCy weather would lead to land masses shedding heat with the extra snow insulation impeding the escape of heat from the continents. Not sure it matters that much given how little heat the land stores relative to the oceans.

Dharma Rupa

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Re: 2018 sea ice area and extent data
« Reply #205 on: February 25, 2018, 08:50:26 PM »
Hmm i don't understand how WACCy weather would lead to land masses shedding heat with the extra snow insulation impeding the escape of heat from the continents. Not sure it matters that much given how little heat the land stores relative to the oceans.

Your last sentence answered your first.  Land doesn't retain heat very well when compared to water.  This leads to the ocean remaining warm in the dark of night while the land gets cold and snowy.

I think that the "Cold Continents" are only in comparison to the warm Arctic, and that they are warming up too -- just nowhere near as fast.

oren

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Re: 2018 sea ice area and extent data
« Reply #206 on: February 25, 2018, 09:43:32 PM »
The elephant in the room here is of course that extent is lowest in core arctic seas and high in peripheral seas. Is anyone cumulatively plotting that and comparing it with previous years?

Interesting to see this trend reflected in the CAB itself. Perhaps the lift off of ice from Greenland is beginning to show up in CAB extent. Short of more crazy weather, which it seems we'll be seeing a bit of a reprieve from, the recent losses in CAB extent should be recovered relatively quickly.
Bear in mind the CAB also includes that area north of Svalbard that is typically open water in February in recent yeara. On top of that you have the newly open water north of Greenland, which is surely reflected in the numbers, but will hopefully refreeze before season's end.

Hautbois

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Re: 2018 sea ice area and extent data
« Reply #207 on: February 25, 2018, 10:15:19 PM »
Updated maxima comparisons chart. I've picked out the daily trajectory of 2017 as well in this one.

Yesterday (day 55) was the max date for 2007. The statistical mode is day 65 (March 6th most years).


Pmt111500

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Re: 2018 sea ice area and extent data
« Reply #208 on: February 26, 2018, 04:00:50 AM »
I think that the "Cold Continents" are only in comparison to the warm Arctic, and that they are warming up too -- just nowhere near as fast.

Siberia is only in -30Cs so it's warm? In fact, no where on Northern hemisphere is currently -40C, coldest I could find was -38C in interior Greenland, couldn't survive that anymore for lack of proper insulated trousers. With doubled long johns you get by with -25C quite ok, but not with biting wind, the heat loss could get you serious frostbite after 2 hours. Not that I plan to be out for that long anyway.

So, the East Antarctic interior with ~-45C is the coldest place on earth also in 2018 late feb - NH winter.
« Last Edit: February 26, 2018, 04:27:37 AM by Pmt111500 »
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kiwichick16

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Re: 2018 sea ice area and extent data
« Reply #209 on: February 26, 2018, 08:46:40 AM »
its still , theoretically, summer down here.......although it has cooled off somewhat in the last couple of weeks

NZ had its hottest January on record this year

Neven

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Re: 2018 sea ice area and extent data
« Reply #210 on: February 26, 2018, 08:47:44 AM »
You guys are keeping it short, so that's good, but do try to stay on topic.
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #211 on: February 26, 2018, 11:54:20 AM »
On-topic:-

JAXA data for the 25th Feb. Extent 13,638,724 km2 The average daily increases of 50k for the the five days have switched to a 2 day decrease of 24k, and as pointed out already, this means 2018 is in its lonely furrow again. (2017 posted big extent losses in the next 3-4 days.)
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Wipneus

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Re: 2018 sea ice area and extent data
« Reply #212 on: February 26, 2018, 02:21:13 PM »
NSIDC NT area makes a nosedive as it is sensitive to the near 0oC temperatures.

Attached are graphs of extent and area within the Arctic Basin.

gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #213 on: February 26, 2018, 05:18:08 PM »
After those "Good Heavens" graphs from Wipneus, here is the NSIDC data for the 25th Feb on the seas around the CAB.

Bering Sea decline has changed to an 11k increase,
Okhotsk a small decline of 5k,
Chukchi a small increase of 3k,
Baffin daily increase down to 9k,
Greenland continues to decline (4k),
Barents increase continues but slowing down (6k).

Small beer compared with what is happening in the CAB, but definitely a switch. Too many lines on the table, put to one side until the next event.


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Ice Shieldz

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Re: 2018 sea ice area and extent data
« Reply #214 on: February 26, 2018, 06:32:23 PM »
Big Beer  ;)

Thanks gerontocrat and Wipneus for all the excellent updates and charts!

https://sites.google.com/site/arcticseaicegraphs/regional

Wipneus

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Re: 2018 sea ice area and extent data
« Reply #215 on: February 27, 2018, 03:59:09 PM »
Area dives further.

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Re: 2018 sea ice area and extent data
« Reply #216 on: February 27, 2018, 05:02:21 PM »
The CAB is pretty gobsmacking....

It looks from Wip's chart...for at least the years shown....that this would be the first "January max" (Assuming of course...that the Jan numbers hold).  Other maximum's in the CAB looked to have happened in Feb or March.

And of course....one of these years.....we're going to get a double whammy of (1) an early start like this year, and then (2) a bad middle/end of year melt season.  Just a matter of time... and the clock is ticking.

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Dharma Rupa

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Re: 2018 sea ice area and extent data
« Reply #217 on: February 27, 2018, 05:27:44 PM »
The CAB is pretty gobsmacking....

It looks from Wip's chart...for at least the years shown....that this would be the first "January max" (Assuming of course...that the Jan numbers hold).  Other maximum's in the CAB looked to have happened in Feb or March.

And of course....one of these years.....we're going to get a double whammy of (1) an early start like this year, and then (2) a bad middle/end of year melt season.  Just a matter of time... and the clock is ticking.

I'd divide those graphs into three categories:  regions which always are full most of the year, regions that don't really matter because they always melt out, and the (2) regions that are open to other oceans.

The regions that are open to either the Atlantic or the Pacific are really scary this year.

jdallen

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Re: 2018 sea ice area and extent data
« Reply #218 on: February 27, 2018, 06:31:39 PM »
The CAB is pretty gobsmacking....

It looks from Wip's chart...for at least the years shown....that this would be the first "January max" (Assuming of course...that the Jan numbers hold).  Other maximum's in the CAB looked to have happened in Feb or March.

And of course....one of these years.....we're going to get a double whammy of (1) an early start like this year, and then (2) a bad middle/end of year melt season.  Just a matter of time... and the clock is ticking.

Also, unlike 2016/2017, the new ice forming now will not have 90 60 days of "cooler" weather like last year to thicken up.  The drop off last year started in the first week of February and continued through the rest of the season.  This year the heat is rocketing up starting about the same time, and there aren't a lot of indications to suggest the cold will be able to return and solidly establish itself.
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #219 on: February 27, 2018, 07:46:15 PM »
Wait Small !  (South Pacific Pidgin)

NSIDC Daily Extent Data as at 26th Feb up 60k to 14.203 million km2, now only 121k less than 2017.
Bering Sea up 24k etc (see table below).

cci-reanalyzer - Arctic Temp anomaly down to 4.8 degrees celsius now,
                     - Arctic Temp anomaly down to ZERO degrees celsius on 6th March.
                     - strong +ve anomaly only in Baffin over next few days.

JAXA shows extent gain mostly above average in last few days

Still at least two weeks to go in average freezing season.

It ain't over 'til its over.
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AbruptSLR

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Re: 2018 sea ice area and extent data
« Reply #220 on: February 27, 2018, 08:16:19 PM »
Scribbler has a nice article related to this topic:

Title: "A Large Area of Open Water Forms in the Melting Sea Ice North of Greenland During February"

https://robertscribbler.com/2018/02/26/a-large-area-of-open-water-forms-in-the-melting-sea-ice-north-of-greenland-during-february/

Extract: "Only a month and a half of typical freeze season remains. But ten day forecasts indicate that Arctic region mean temperatures might return closer to normal ranges (0 to 1 C above average as opposed the 3-6 C above average) and could allow for some moderate recovery of the substantially reduced winter ice pack.

Overall, though, the tale so far has been one of highly unusual melt and warming. One that highlights the serious and worsening impacts of human-caused warming and related polar amplification."
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #221 on: February 27, 2018, 08:21:35 PM »
I agree with
Quote
Overall, though, the tale so far has been one of highly unusual melt and warming. One that highlights the serious and worsening impacts of human-caused warming and related polar amplification.

If I didn't, I would not be on this forum.

But Armageddon is still postponed (at least for a while?)
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Wherestheice

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Re: 2018 sea ice area and extent data
« Reply #222 on: February 28, 2018, 06:31:34 AM »
I agree with
Quote
Overall, though, the tale so far has been one of highly unusual melt and warming. One that highlights the serious and worsening impacts of human-caused warming and related polar amplification.

If I didn't, I would not be on this forum.

But Armageddon is still postponed (at least for a while?)

I think the real Armageddon (if it happens), would be in the summer. All we need is a bad summer to really destroy the ice. :(
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #223 on: February 28, 2018, 02:27:18 PM »
NSIDC Daily Extent Data as at 27th Feb down 27k to 14.175  million km2, now only 109 k less than 2017.

Peripheral Seas data attached in table. All changing as warmth moves around the Arctic
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #224 on: February 28, 2018, 05:51:01 PM »

I think the real Armageddon (if it happens), would be in the summer. All we need is a bad summer to really destroy the ice. :(

Probably not (yet ).
The two dramatic events in the last 15 years when looking at the extent minimum were in 2007 and 2012. In those years extent loss from max to min were 10 million and 11.1 million respectively. Assuming a 2018 maximum of about 13.8 million, resulting minimum would be 3.8 million and 2.7 million km2. Also remember that the 2012 maximum was well above average (by about 0.45 million).

So for 2018 to record the destruction of Arctic Sea Ice would require things to happen completely beyond what has happened before.
Yes, Arctic temperatures have risen,
Yes, Global Ocean Heat has risen,
but I believe so far on a slowly accelerating incremental basis.

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Dharma Rupa

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Re: 2018 sea ice area and extent data
« Reply #225 on: February 28, 2018, 07:02:13 PM »
I think the real Armageddon (if it happens), would be in the summer. All we need is a bad summer to really destroy the ice. :(

All we need to really destroy the ice is for the Gulf Stream to decide to pass to the west of Greenland, and it won't matter what time of year.  It is very unclear what is going on in the North-west Atlantic, but it isn't normal.

Cid_Yama

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Re: 2018 sea ice area and extent data
« Reply #226 on: February 28, 2018, 07:11:07 PM »
Your calculation leaves out a couple very important variables.  The biggest one being the difference in sea ice volume.

Your assumption that what happened 11 years ago and 6 years ago has any bearing on what happens this year, when conditions this year are unprecedented, is simplistic and flawed.

Both weather patterns, and sea and air temperatures are vastly different.  Ocean currents have shifted.  The energy in the atmosphere has increased.

The Arctic is a very different place than it was.

 


Jim White at the 2014 AGU.


 
« Last Edit: February 28, 2018, 07:19:38 PM by Cid_Yama »

gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #227 on: February 28, 2018, 07:30:50 PM »

Both weather patterns, and sea and air temperatures are vastly different. 


Different, yes. Changed, yes.
Vastly different  ? Where is the data to prove "vastly".

One amazing cyclone followed by an amazing SSW are events, not necessarily game changers. The Arctic is currently cooling down, maximum extent can now only be a fraction below 2017.
The 2012 melting season finished with the GAC-2012 cyclone. many thought that was it, the tipping point, but it was not.

Without data, "vastly" is mere speculation. History does tell us what has been the maximum deviation from the trend line. What has changed to make a larger deviation possible ?

ps: Volume Loss according to PIOMAS is still declining very much on the linear regression line. In a few days February will be published. Then we will see some more data.
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Alexander555

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Re: 2018 sea ice area and extent data
« Reply #228 on: February 28, 2018, 07:36:14 PM »
Maybe it's still possible. If extent goes up from this point. There are a few places where there is very little ice so far, like Bering. And it's gaining for the moment. And there are a few places where there is more ice than average , like Baffin and Ochotsk. If they hold on for a few weeks. And the same time i have seen many days of big anomolies on the Arctic itself. So that ice is probably not in a very good condition. So we have more ice that will be gone for sure, and plenty in a bad condition.

Hefaistos

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Re: 2018 sea ice area and extent data
« Reply #229 on: February 28, 2018, 08:57:47 PM »
I think the real Armageddon (if it happens), would be in the summer. All we need is a bad summer to really destroy the ice. :(

All we need to really destroy the ice is for the Gulf Stream to decide to pass to the west of Greenland, and it won't matter what time of year.  It is very unclear what is going on in the North-west Atlantic, but it isn't normal.

Not so easy! First need to answer how the Gulf stream might possibly overtake/reverse the Labrador current with its 5 sverdrups.
https://en.wikipedia.org/wiki/Labrador_Current

Iceismylife

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Re: 2018 sea ice area and extent data
« Reply #230 on: February 28, 2018, 11:15:09 PM »
I think the real Armageddon (if it happens), would be in the summer. All we need is a bad summer to really destroy the ice. :(

All we need to really destroy the ice is for the Gulf Stream to decide to pass to the west of Greenland, and it won't matter what time of year.  It is very unclear what is going on in the North-west Atlantic, but it isn't normal.

Not so easy! First need to answer how the Gulf stream might possibly overtake/reverse the Labrador current with its 5 sverdrups.
https://en.wikipedia.org/wiki/Labrador_Current
Open up a significant erea of hater inside of 80 north and you generate bottom water.  That pulls the surface water north.  Having the gulf stream go up the west side of Greenland is easy.

Archimid

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Re: 2018 sea ice area and extent data
« Reply #231 on: February 28, 2018, 11:19:29 PM »
Is 2sd "vastly different"? Because thats what we are dealing with in many key metrics.
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Dharma Rupa

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Re: 2018 sea ice area and extent data
« Reply #232 on: March 01, 2018, 12:59:19 AM »
I think the real Armageddon (if it happens), would be in the summer. All we need is a bad summer to really destroy the ice. :(

All we need to really destroy the ice is for the Gulf Stream to decide to pass to the west of Greenland, and it won't matter what time of year.  It is very unclear what is going on in the North-west Atlantic, but it isn't normal.
Not so easy! First need to answer how the Gulf stream might possibly overtake/reverse the Labrador current with its 5 sverdrups.
https://en.wikipedia.org/wiki/Labrador_Current
Just watch what has been happening in the Gulf of Maine the last 5 years and ask the Lobstermen.

FishOutofWater

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Re: 2018 sea ice area and extent data
« Reply #233 on: March 01, 2018, 01:44:03 AM »
You need to consider the vorticity (spin) of different water masses. Gulf Stream water drifts towards Europe both because it's driven that direction by the westerlies and because it turns right as it moves north because of the Coriolis effect (the effects of the spin from earth's rotation).

Please don't suggest non-physical things that violate the conservation of angular momentum.

Iceismylife

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Re: 2018 sea ice area and extent data
« Reply #234 on: March 01, 2018, 02:44:46 AM »
...
Please don't suggest non-physical things that violate the conservation of angular momentum.
But in a random chaotic system something as small as the flapping of a butterfly wing can turn into a hurricane... Or a GAC. Or two. 

As far as violating angular momentum that doesn't need to be crossed. Drop water into the bottom of the abyss at the north pole and it has to come from somewhere.

oren

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Re: 2018 sea ice area and extent data
« Reply #235 on: March 01, 2018, 03:06:50 AM »
This is becoming waaay off-topic here.

Neven

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Re: 2018 sea ice area and extent data
« Reply #236 on: March 01, 2018, 09:43:53 AM »
But in a random chaotic system something as small as the flapping of a butterfly wing can turn into a hurricane... Or a GAC. Or two.

Solution: Kill all the butterflies.  ;D

I'm late to this party, so I'm not going to delete all those comments. But, please, people, stay on topic. Take each other's hand and go to the appropriate threads, or create them. It's a forum, not a chat room.
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #237 on: March 01, 2018, 12:32:45 PM »
Hullo Neven,

thanks for being gentle with the chide.

JAXA ARCTIC SEA ICE EXTENT DATA AS AT 28TH FEB 13,727,837 km2. Up again - by 46k, a big increase for this time of year. Extent is just 150k less than the 2017 maximum on 6th March. On average, 15 days, 1.8% and 0.18 million of extent gain to go, leading to a maximum of 13.90 million, i.e. to all intents and purposes the same as 2017.

Does this mean the ice is in as good condition as last year to meet the melting season? I think not. The spectacular images and animations on the freezing thread show the extent of damage to ice in the CAB. I suspect that much of the recent extent gains is due to this broken up ice being shoved in a generally southward direction into the Baffin and Greenland seas.

I wonder when our Guv'nor will feel the time is right to open the 2018 melting season threads. Can't be long.
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Neven

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Re: 2018 sea ice area and extent data
« Reply #238 on: March 01, 2018, 01:06:05 PM »
I wonder when our Guv'nor will feel the time is right to open the 2018 melting season threads. Can't be long.

Probably 7-14 days from now, given that the AO is projected to strongly negative.
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gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #239 on: March 01, 2018, 01:52:40 PM »
NSIDC Daily Extent Data as at 28th Feb UP 110k to 14.285  million km2, now only 20k less than 2017.

Peripheral Seas data attached in table. All continues to change as warmth moves around the Arctic, e.g. Baffin (warmer) Greenland (colder). Bering Sea up 70k in 3 days, while Okhotsk starts to fall.
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DavidR

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Re: 2018 sea ice area and extent data
« Reply #240 on: March 01, 2018, 08:11:36 PM »
I wonder when our Guv'nor will feel the time is right to open the 2018 melting season threads. Can't be long.

Probably 7-14 days from now, given that the AO is projected to strongly negative.
I think 1 March should be declared the official opening day of the Melting Thread and 1 September the official opening day of the Freezing Thread.   In the NSIDC record several  years have already  passed their maximums.
Toto, I've a feeling we're not in Kansas anymore

Neven

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Re: 2018 sea ice area and extent data
« Reply #241 on: March 01, 2018, 08:39:00 PM »
Let's not discuss that here. This thread would be a better place.
« Last Edit: March 01, 2018, 09:05:20 PM by Neven »
Compare, compare, compare

gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #242 on: March 02, 2018, 01:22:05 PM »
JAXA ARCTIC SEA ICE EXTENT DATA AS AT 1st March 13,759,813  km2. Up again - by 32k, a greater than average increase for this time of year. Extent is just 120k less than the 2017 maximum on 6th March. On average, 14 days, 1.4% and 0.14 million of extent gain to go, leading to a maximum of 13.89 million, i.e. to all intents and purposes the same as 2017.

But 2018 extent still in its lonely furrow, 42k less than 2017, but likely to be second to 2015 for a bit very soon.

Look at 2012 - on Mar 1st 0.77 million greater extent than 2018, and about to go a lot higher (for about two weeks in April was above the 30 year average used by NSIDC). And yet produced the record low in 6 months.

Also attach a table of differences over the years. 1.8 million km2 less winter ice than in the 1980's. The decline in winter ice is still gradual.
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"Damn, I wanted to see what happened next" (Epitaph)

RikW

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Re: 2018 sea ice area and extent data
« Reply #243 on: March 02, 2018, 04:29:28 PM »
Having above average changes isn't really surprising when we are so extremely low on extent. Because there is a lot of sea/ocean that is normally frozen that isn't frozen and it still is in most parts of the arctic below 0 degrees Celsius. And for area max it doesn't really matter if we have ice that is 10 cm thick or 2 meters thick. It still is covered with ice, until melting and/or wind/waves etc. starts

gregcharles

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Re: 2018 sea ice area and extent data
« Reply #244 on: March 02, 2018, 05:45:49 PM »
2018 set record lows in the NIPR Extent data almost every day in February, finally wiping 2006 off the chart in the process. The only pre-2010 year left with daily low extent records is 2007, with four days in October. Given that 2016 is about to dominate the early melt season and 2012 the late melt, I'm not sure how many more records 2018 will be logging for a while. There's no doubt it owns Q1 though -- well, at least until next year.  :(

(A small aside: the NIPR CSV data now blanks out Feb. 29 data for non-leap years. It used to fill in those gaps, I think with the value from March 1. I like it better this way, but have they said anything about why they changed?)

gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #245 on: March 02, 2018, 06:26:24 PM »
(A small aside: the NIPR CSV data now blanks out Feb. 29 data for non-leap years. It used to fill in those gaps, I think with the value from March 1. I like it better this way, but have they said anything about why they changed?)

When making my spreadsheets Feb 29th was a real pain in the butt. I thought about it and realised that Feb 29th is at a time of year when extent gain (Arctic) and extent loss or gain (Antarctic) are minimal (transition season). But none of my stuff is going to appear in a peer-reviewed scientific publication). So I have to tell you that Feb 29 does not exist in my spreadsheets. SHAME ON ME.

No worries until 2020 ( I will take a day off on Feb 29).
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

oren

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Re: 2018 sea ice area and extent data
« Reply #246 on: March 02, 2018, 11:06:35 PM »
Gerontocrat, I do the same with the annoying 29th of Feb... unless dealing with PIOMAS, which has numbered days rather than dates.

gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #247 on: March 03, 2018, 11:15:25 AM »
JAXA ARCTIC SEA ICE EXTENT DATA AS AT 2nd March 13,736,896 km2. Down  - by 23k, a which makes a change. Baffin and Bering regions still very warm ?

Extent is 140k less than the 2017 maximum on 6th March. On average, 13 days, 1.2% and 0.12 million of extent gain to go, leading to a maximum of 13.86 million, i.e. to all intents and purposes the same as 2017.

2018 extent still in its lonely furrow, 51k less than 2017, but still likely to be second to 2015 for a bit very soon. PIOMAS update - "Wherefore Art Thou, PIOMAS".
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: 2018 sea ice area and extent data
« Reply #248 on: March 03, 2018, 02:32:35 PM »
NSIDC Daily Extent Data as at 2nd March down 55k to 14.302 million km2, now 77k less than 2017.

Peripheral Seas data attached in table. All continues to change as warmth moves around the Arctic, e.g. Baffin (warmer) Greenland (colder and northerly winds pushing ice south).
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

Pmt111500

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Re: 2018 sea ice area and extent data
« Reply #249 on: March 03, 2018, 06:26:24 PM »
Yeah, the leap day problem is a pesky one. To solve it for CT SIA, I had to convert all the dates to metric time. And still you get one line too many for complete uniform graphing for the data. I just split the difference over the whole year... But to be very accurate, technically, you'd need to start to number the datapoints of a year at six hour intervals on Metric time over the four year period. Thus you'd get staggered points of datevalues on graphs of several years. I figured that as I did not know the exact times of data acquisition, though the satellites orbit is very regular, this didn't matter. Anyway the fixed year+date/365 or date/366 made for prettier graphs at least with some illusion i knew what i was doing. And please don't ask me what to do about year 2100 which doesn't fit to the Julian calendar system.
« Last Edit: March 03, 2018, 06:44:34 PM by Pmt111500 »
Amateur observations of Sea Ice since 2003.