Arctic Sea Ice Extent, Area, and Volume

[zenmsav6810]

2 minutes ago, skierinvermont said:

Given this decline has been persistent and today's value is 160k lower than the value 3 days ago it's not due to cloud cover or measurement error. If we saw a 100k blip down and then it went right back up the next day then a big portion of the dip could have been measurement error. But when the measurement is consistent across 3 days, and in fact just keeps getting lower, it's not measurement error. 

A calving event or ice shelf breaking off would have no effect on sea ice area. If anything land ice or ice shelves calving would increase sea ice area because previously land bound ice would now be afloat and thus newly within the sea ice boundary area.

Sea ice decreases this time of year are probably largely due to wind compaction. We could also be seeing newly formed ice from the last week or two melting. When it first freezes it would be very thin and then if the weather changes it might melt again.

Normally any compaction would be compensated for by the rapid freezing going on elsewhere. The ice area and volume should be exploding this time of year. So what we're really likely seeing is a general arctic-wide lack of rapid freezing combined with either compaction and/or melting of newly formed ice. 

1

Yeah, that makes sense. I guess we're all doomed.

[skierinvermont]

1 minute ago, zenmsav6810 said:

Yeah, that makes sense. I guess we're all doomed.

Well I wouldn't say that. But as the climate warms we're going to see more and more extreme anomalies like this.

We're so far below even the modern average for the date. And what so often gets forgot in discussions of sea ice is that 1980-2000 is not "average" or normal for sea ice. There's strong evidence that there was lots more sea ice earlier in the century. The highest years of the early 1980s might be a little closer to an early 20th century normal.

[chubbs]

5 hours ago, skierinvermont said:

Well I wouldn't say that. But as the climate warms we're going to see more and more extreme anomalies like this.

We're so far below even the modern average for the date. And what so often gets forgot in discussions of sea ice is that 1980-2000 is not "average" or normal for sea ice. There's strong evidence that there was lots more sea ice earlier in the century. The highest years of the early 1980s might be a little closer to an early 20th century normal.

This chart illustrates how 2016 compares to the range of extent in previous years.  The extreme outer edge represents the coldest years from the early portion of the satellite record. Note that 2016 is not the least expansive year in all areas.

[Sophisticated Skeptic]

 

 

[tacoman25]

12 hours ago, skierinvermont said:

troll

One words posts are lame. Repeating the same one word post is even more lame.

I've been here long enough, you should know I'm not a troll. Sometimes I just like to bring a slightly different perspective to the echo chamber. Sometimes that includes the lighter side of things.

[tacoman25]

11 hours ago, skierinvermont said:

Well I wouldn't say that. But as the climate warms we're going to see more and more extreme anomalies like this.

We're so far below even the modern average for the date. And what so often gets forgot in discussions of sea ice is that 1980-2000 is not "average" or normal for sea ice. There's strong evidence that there was lots more sea ice earlier in the century. The highest years of the early 1980s might be a little closer to an early 20th century normal.

This is somewhat true, but it really depends on what part of the 20th century you're talking about. There's evidence that the 1980s probably had close to or higher extent than the 1940s-1950s, and perhaps the 1920s as well.

 

[Amped]

57 minutes ago, tacoman25 said:

One words posts are lame. Repeating the same one word post is even more lame.

I've been here long enough, you should know I'm not a troll. Sometimes I just like to bring a slightly different perspective to the echo chamber.

The best way to become a troll magnet is to take jokes seriously.

[csnavywx]

We're at 8.3M. In order to avoid getting a new SIE low-max record, extent will have to increase by 5.7M before maximum. The record increase between now and maximum is 5.2M, set in 2012-2013. Still possible, but getting to be a tall order.

[SN_Lover]

Almost off the charts...

 

 

[skierinvermont]

21 hours ago, tacoman25 said:

This is somewhat true, but it really depends on what part of the 20th century you're talking about. There's evidence that the 1980s probably had close to or higher extent than the 1940s-1950s, and perhaps the 1920s as well.

 

I would be greatly interested in such evidence. I hope you are not referring to anecdotal reports of submarines surfacing at the north poll etc.

Studies that actually compiled airplane recon and ship data come to a very different conclusion. The highest years of the early 80s might have been similar to the lowest years of the 40s:

Also I don't want to hear the same old dismissal of these studies because they look too "flat". As you go back farther on the graph the data is smoothed because there is less data and more uncertainty. To reduce uncertainty they combine data from multiple years. Thus it represents the multi-year average well, but doesn't capture all the annual variability. The data is smoothed. That doesn't make it "wrong" or "suspicious" as you and others have suggested.

 

 

 

[donsutherland1]

4 hours ago, skierinvermont said:

I would be greatly interested in such evidence. I hope you are not referring to anecdotal reports of submarines surfacing at the north poll etc.

Studies that actually compiled airplane recon and ship data come to a very different conclusion. The highest years of the early 80s might have been similar to the lowest years of the 40s:

Also I don't want to hear the same old dismissal of these studies because they look too "flat". As you go back farther on the graph the data is smoothed because there is less data and more uncertainty. To reduce uncertainty they combine data from multiple years. Thus it represents the multi-year average well, but doesn't capture all the annual variability. The data is smoothed. That doesn't make it "wrong" or "suspicious" as you and others have suggested.

 

 

 

Fantastic comparative information.

[donsutherland1]

Ice extent data from 2003-16 (except for Fall 2016 and Annual 2016):

 

 

 

 

[Sophisticated Skeptic]

^from spaceweather.com

The large coronal hole to effect earth again...the next few days. 

and for those that think it's ridiculous to compare the 2. 

Quote

Traveling across freezing space should suck all the heat from the plasma by the time it nears Earth, but the solar waves detected near our planet are still hot. Scientists think something is happening within the plasma to generate heat.

http://blogs.agu.org/geospace/2015/01/05/measuring-temperature-solar-winds/

 

It's BOTH poles that are taking hits currently.   When solar wind / coronal holes unleash....the Poles take the biggest hits.

Dunno why i'm the only one correctly identifying this...while others are blaming global warming or some other nonsense.  What's going on at both the north and south poles currently is unprecedented .  

[tacoman25]

9 hours ago, skierinvermont said:

I would be greatly interested in such evidence. I hope you are not referring to anecdotal reports of submarines surfacing at the north poll etc.

Studies that actually compiled airplane recon and ship data come to a very different conclusion. The highest years of the early 80s might have been similar to the lowest years of the 40s:

Also I don't want to hear the same old dismissal of these studies because they look too "flat". As you go back farther on the graph the data is smoothed because there is less data and more uncertainty. To reduce uncertainty they combine data from multiple years. Thus it represents the multi-year average well, but doesn't capture all the annual variability. The data is smoothed. That doesn't make it "wrong" or "suspicious" as you and others have suggested.

 

 

 

 

The honest answer is that it's an apples to oranges comparison, and no one knows for sure how extent from the first half of the 20th century compares to the satellite era. The graph above is one educated guess, but far from the only estimate. This post goes into great detail on the difficulties of comparing sea ice extent measurements back then to now: https://judithcurry.com/2013/04/10/historic-variations-in-arctic-sea-ice-part-ii-1920-1950/ You may not agree with the conclusion, but the reasoning is thorough and well laid out.

What we do know for sure is that the Arctic has gone through cyclical warming and cooling periods that are much more variable than lower latitudes. In the 1980s, the Arctic was in one of its cooler phases, and given the amount of AGW to that point and total variation that the Arctic climate sees naturally, it's not at all unreasonable to assume that some of the warm phases of the Arctic earlier in the 20th century were probably warmer than the final cool phase of the 20th century. Ice extent typically follows temperature, to a certain degree.

 

 

[donsutherland1]

1 hour ago, Bacon Strips said:

^from spaceweather.com

The large coronal hole to effect earth again...the next few days. 

and for those that think it's ridiculous to compare the 2. 

http://blogs.agu.org/geospace/2015/01/05/measuring-temperature-solar-winds/

 

It's BOTH poles that are taking hits currently.   When solar wind / coronal holes unleash....the Poles take the biggest hits.

Dunno why i'm the only one correctly identifying this...while others are blaming global warming or some other nonsense.  What's going on at both the north and south poles currently is unprecedented .  

Coronal holes have been observed since the 1950s (https://www.cfa.harvard.edu/~scranmer/Preprints/eaaa_holes.pdf). If coronal holes were largely responsible for the current low ice conditions in the Arctic and Antarctic regions, one should have seen similar issues across time. That there is a linear decline in Arctic sea ice underway suggests that something other than coronal holes is responsible, given that they've been occurring regularly.

[skierinvermont]

1 hour ago, tacoman25 said:

 

The honest answer is that it's an apples to oranges comparison, and no one knows for sure how extent from the first half of the 20th century compares to the satellite era. The graph above is one educated guess, but far from the only estimate. This post goes into great detail on the difficulties of comparing sea ice extent measurements back then to now: https://judithcurry.com/2013/04/10/historic-variations-in-arctic-sea-ice-part-ii-1920-1950/ You may not agree with the conclusion, but the reasoning is thorough and well laid out.

What we do know for sure is that the Arctic has gone through cyclical warming and cooling periods that are much more variable than lower latitudes. In the 1980s, the Arctic was in one of its cooler phases, and given the amount of AGW to that point and total variation that the Arctic climate sees naturally, it's not at all unreasonable to assume that some of the warm phases of the Arctic earlier in the 20th century were probably warmer than the final cool phase of the 20th century. Ice extent typically follows temperature, to a certain degree.

 

 

 

I read through most of that article and the comments and am fairly unimpressed. It's a stew of anecdotes (no saying how cherrypicked they might be) without any objective data compilation and analysis.

[skierinvermont]

The "back to 1870" project that the author of that blog post references hoping they will show less ice 1920-1940 than the early 2000s was completed recently. It did not live up to the author's expectations. It did increase the variability somewhat, but the lowest years of the 1930s is similar to the 1980s.

The study produced was titled " A database for depicting Arctic sea icevariations back to 1850. " and was published earlier this year in the journal Geogrpahical Review.

https://www.carbonbrief.org/wp-content/uploads/2016/08/Walsh-et-al.-2016-Fig8.png

 

http://cires.colorado.edu/news/reconstructing-arctic-history

 

[ORH_wxman]

We have garbage data from the North American side in the mid-20th century....ironically the best data on the Asian side of the pole for sea ice back then.

The Mahoney et al paper is probably the most robust in the literature for sea ice records...but of course it only covers about 3/4th of the arctic region that would lose ice when we're comparing to the 1980s/1990s...we don't have good Beaufort Sea ice data:

 

 

 

Then of course you can go on temperatures....the late 1930s through the early 1950s had temperatures very comparable to the 1980s...and at least into the early 1990s.

 

 

 

 

We'll never know for certain because we don't have a full dataset. But I think there is absolutely some compelling evidence that sea ice had years comparable to the 1980s/1990s back in the mid-20th century.

 

 

 

 

[nzucker]

The coronal hole thing probably explains the blip, but it's superimposed on a long-term decline in Arctic sea ice that allows for such abnormally poor periods in ice extent.

Re: the temp anomaly map, that's an extreme example of the -AO warm arctic, cold continents pattern. +24C anomalies in the Arctic while Siberia, Southwest Asia, and Western North America see near record cold. It's actually fairly encouraging to see such large areas of cold anomalies, which suggest Winter 16-17 in the Northern Hemisphere will be MUCH COLDER than Winter 15-16 was in the Super El Nino, in which almost nowhere finished below average.

[chubbs]

8 hours ago, nzucker said:

The coronal hole thing probably explains the blip, but it's superimposed on a long-term decline in Arctic sea ice that allows for such abnormally poor periods in ice extent.

Re: the temp anomaly map, that's an extreme example of the -AO warm arctic, cold continents pattern. +24C anomalies in the Arctic while Siberia, Southwest Asia, and Western North America see near record cold. It's actually fairly encouraging to see such large areas of cold anomalies, which suggest Winter 16-17 in the Northern Hemisphere will be MUCH COLDER than Winter 15-16 was in the Super El Nino, in which almost nowhere finished below average.

Yup, I am more optimistic about our winter than 75-90N. Here is Nov 2009.

 

[Sophisticated Skeptic]

12 hours ago, donsutherland1 said:

Coronal holes have been observed since the 1950s (https://www.cfa.harvard.edu/~scranmer/Preprints/eaaa_holes.pdf). If coronal holes were largely responsible for the current low ice conditions in the Arctic and Antarctic regions

Yes,  but it's the unusually large size and consistency of these very large coronal holes that we haven't seen ever (so many) occur back to back in a year's time.

I don't even see 1 other person mentioning the 'possibility' of this being the issue...anywhere.  95% of the horde are all caught up in climate change this and that.    Somewhat seems like their 'scared' to mention the sun as the culprit.  

I guess if there's no politics involved, they can't mention it as the problem...since there's no silver bullet to fix the sun.

[donsutherland1]

17 minutes ago, Bacon Strips said:

Yes,  but it's the unusually large size and consistency of these very large coronal holes that we haven't seen ever (so many) occur back to back in a year's time.

I don't even see 1 other person mentioning the 'possibility' of this being the issue...anywhere.  95% of the horde are all caught up in climate change this and that.    Somewhat seems like their 'scared' to mention the sun as the culprit.  

I guess if there's no politics involved, they can't mention it as the problem...since there's no silver bullet to fix the sun.

Do you have a source of data that indicates the current coronal holes are largely unprecedented?

[Juliancolton]

2 hours ago, donsutherland1 said:

Do you have a source of data that indicates the current coronal holes are largely unprecedented?

Coronal holes always become bigger and more numerous during the years leading up to solar minimum. Nothing new as far as I can tell.

[donsutherland1]

58 minutes ago, Juliancolton said:

Coronal holes always become bigger and more numerous during the years leading up to solar minimum. Nothing new as far as I can tell.

Thanks. That's what I've read. So, as you noted, there doesn't appear to be anything unusual going on right now.

[Sophisticated Skeptic]

4 hours ago, donsutherland1 said:

Do you have a source of data that indicates the current coronal holes are largely unprecedented?

 

From monitoring coronal hole data for decades, it is 'not' normal.   The size of these holes.  Even during solar minimums in the past.

[pazzo83]

51 minutes ago, Bacon Strips said:

 

From monitoring coronal hole data for decades, it is 'not' normal.   The size of these holes.  Even during solar minimums in the past.

"source of data" != your anecdotal monitoring

[Mallow]

50 minutes ago, Bacon Strips said:

 

From monitoring coronal hole data for decades, it is 'not' normal.   The size of these holes.  Even during solar minimums in the past.

There is no conspiracy here. Extraordinary claims require extraordinary evidence--anecdotes based on memory are about the weakest form of evidence one could present. In other words, you're going to have to present data (again, not anecdotes, but real, comparative data) which support your claims in order for people to take your hypothesis more seriously.

[donsutherland1]

20 hours ago, Bacon Strips said:

 

From monitoring coronal hole data for decades, it is 'not' normal.   The size of these holes.  Even during solar minimums in the past.

The issue is that in the absence of concrete data, it's difficult to draw firm conclusions with any degree of confidence.

[Sophisticated Skeptic]

sometimes you have to think outside the box, and look at data from outside the box.  

everything going on with the planet, isn't always going to be handed over on a silver platter.   Public data is only a piece of the puzzle. 

This year alone has been exceptional (record breaking) in terms of both Coronal Holes and Ice Melt.    Shouldn't take much processing to connect the dots. 

[Thunderbomb1982]

On ‎11‎/‎21‎/‎2016 at 8:36 PM, skierinvermont said:

 

I read through most of that article and the comments and am fairly unimpressed. It's a stew of anecdotes (no saying how cherrypicked they might be) without any objective data compilation and analysis.

You say you are so unimpressed. I agree with the original poster that ice fluctuates at intervals from time to time during our current climate.   Were you around before the 20th century?   The why don't you have the correct maps and justification?? If you are so unimpressed?   I agree with the original poster and once again you have no logical justification.