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The submarine records should go back to the 1950s. Wondering where they are.

L. Hamilton

Kwok & Rothrock (2009) "Decline in Arctic sea ice thickness from submarine and ICESat records: 1958–2008" Geophysical Research Letters doi: 10.1029/2009GL039035

[1] The decline of sea ice thickness in the Arctic Ocean from ICESat (2003–2008) is placed in the context of estimates from 42 years of submarine records (1958–2000) described by Rothrock et al. (1999, 2008). While the earlier 1999 work provides a longer historical record of the regional changes, the latter offers a more refined analysis, over a sizable portion of the Arctic Ocean supported by a much stronger and richer data set. Within the data release area (DRA) of declassified submarine sonar measurements (covering ∼38% of the Arctic Ocean), the overall mean winter thickness of 3.64 m in 1980 can be compared to a 1.89 m mean during the last winter of the ICESat record—an astonishing decrease of 1.75 m in thickness. Between 1975 and 2000, the steepest rate of decrease is −0.08 m/yr in 1990 compared to a slightly higher winter/summer rate of −0.10/−0.20 m/yr in the five-year ICESat record (2003–2008). Prior to 1997, ice extent in the DRA was >90% during the summer minimum. This can be contrasted to the gradual decrease in the early 2000s followed by an abrupt drop to <55% during the record setting minimum in 2007. This combined analysis shows a long-term trend of sea ice thinning over submarine and ICESat records that span five decades.



Cincinnatus , you may be encouraged to know that I agree with all of the reliable and valid peer review studies published since 2005 I could locate that support your point of view that human caused climate change is virtually non-existent and is instead caused by natural variation. Hopefully, this extensive list or should I say expansive list is complete.

However, since there are more knowledgeable posters on here than I, like Jim Hunt, L. Hamilton, Werther, Neven, Epsen, and a number of others, I am sure they may wish to append the list if/when they find any other reliable/valid material published on this premise in addition to this expansive list. (I have included an "End of List" tag so you will know for sure when you have reached the end of this list.)

Happy reading. List of what I consider to be valid/reliable peer reviewed articles that provide reliable/valid evidence that climate change is wholly caused by natural variation and not human activities follows:

End of List


Jim Hunt

Thanks for your kind words Vaughn, and also for your "list" :)

It seems appropriate to mention here the discussion on the forum about the distribution of multi-year versus first year ice, the latter of course being thinner. This year the North Pole (currently at least) is surrounded by the first year variety:

Andy Lee Robinson

A well-researched, comprehensive and thorough list, but perhaps you could compile a more concise and simplified version more suited to the attention span of the typical denier?

Bill Fothergill

@ Vaughn,

This is a blatant attempt at cherry picking.

Why did you fail to mention...



or even

Yours disgustedly A N Other

Espen Olsen

"It’s no surprise that Arctic sea ice is thinning."

And IJIS is already in a melt mood with record lows:


Chris Reynolds


"The big question now, of course, is whether the thinning will continue at this rate or slow down. Hopefully this will become clear in years to come."

This paper shows continuing thinning, as indeed does the PIOMAS data for the bulk of the Arctic - the Central Arctic region.

It may be that I've called it too early in arguing that an inflection is underway from steep volume declines to less of a rate of volume decline, but on balance I think not. My claim of a 'levelling' is merely based on 2010 to 2014 April volumes, this paper only goes up to 2012 so wouldn't really help identify that in view of the noise around the trend.

By 2020, just 5 years, we'll know.


Try here:

Where there are links to data pages such as this:

Some data goes back to the 1950s (IIRC), I have never had cause to use this. During the Clinton administration Al Gore arranged data to be made available to certain scientists. It was secret so I don't know whether this data is now available publicly. The secrecy was because submarine ULS transects were made to find places where missiles could be fired from nuclear submarines hiding under the ice.


@ Chris: As mentioned in the quote by Neven:
"What we see now is a little above the trend, but it’s not inconsistent with it in any way,” Lindsay said. “It’s well within the natural variability around the long-term trend.”
and that is about the last 2 years.
My observation is that if UW was outcasted for being too 'alarmists' and facts turned out to be worse then their model, on top of that we are starting a possible melt a month before the sun comes up.
For anyone that loves the ice, it is very bad news.


It's interesting that the ref's fig 5 (the second figure above) suggests a linear decline in average ice thickness in the central Arctic. That combined with a linear decline in average ice area (roughly as observed) would produce a quadratic decline in volume. Those who have been criticising 'arbitary' quadratic fits to the PIOMAS volumes might like to take note.


Bill, considering no one has appended my list, I consider it complete. How is "complete" cherry-picking? Just curious.


I did indeed look through 3 papers and the answer is that there were not many polar submarine voyages. The interesting NSIDC link from Chris Reynolds shows that the pre-1967 data consists of "traces on paper rolls". So the 1950s-1960s ice measurements are more of a sample than anything comprehensive, which is why there's not much written about them. Not making any point here other than that the data is sparse.

Bill Fothergill


I had started to write a tongue in cheek response, but then realised there was the possibility of a posting lurking therein.

I will polish this up over the next couple of days, and then ask Neven if he wants to put it on this site.

A.N. Other (still disgusted)

Bill Fothergill

About 5 comments earlier on this page, LRC made reference to the possibility of an early onset melt season - even before the sun gets to do its thing. Similar thoughts have been expressed by others on the "Shock News" thread.

Although 2015 has certainly wandered into virgin territory in many of the datasets, if one looks at even the most recent 10 years, this would still seem to be a bit early for the date of the annual maximum. Yes, 2009 saw NSIDC declare the maximum as having been reached on the 28th February, but on the other hand, 2010 and 2014 both saw significant rises in extent deeper into March.

Having said that, the Jaxa figure dated 5th March is now about quarter of a million sq kms down on the current (transient?) maximum, which occurred on Feb 25. The last 7 days have all been daily record lows on Jaxa. In fact, even if the Jaxa extent now starts to rise by 70 thousand sq kms a day, the next 6 days will still all be daily record lows.

On the NSIDC five-day running average shown on their Charctic tool, 2015 slipped fractionally below the erstwhile record low for this time of year (2006) on the 3rd March. Although 2015 is a mere 74 thousand sq kms below the previous daily record low as at 5th March, continued divergence is effectively guaranteed for at least the next three days.

I don't harbour any strong opinions one way or the other as regards 2015, but I do think that eventually there will be a monstrous drop, and an early melt will be one of its harbingers.

Anyway, as regards insolation at high latitudes, I finally found an interactive app that let's one set latitude (range: 90S-90N) and day of the year on two sliders. The app then shows a simple 24 hour graph depicting the insolation rate.

The location is...

Cheers Bill F
(PS Just as a thought, Neven, might you consider doing a link to this from the graphs page?)

Jim Hunt

Perhaps we really are entering "Shock News!" territory? Daily NSIDC extent fell by 107,510 km2 yesterday, and the 5 day average is now rapidly diverging from it's closest competitors:


It's a low sea ice maximum because the northern Pacific has been warm and so the Bering & Okhotsk have low ice. But they melt out in May anyway. This has no bearing on summer Arctic ice melt, and the north Chukchi ice is looking to be thick and resistant to melting out as it has been very cold there. So a bit premature to panic as I know many here yearn to do.

Jim Hunt

You're a braver man than I Cincinnatus, calling the maximum so early!

Ever tasted crow stew?


There is also the North Atlantic Cincinnatus, the entire winter had relentless warm cyclonic intrusions , as I posted: : http://eh2r.blogspot.ca/

It is still on going. But I digress , "But they melt out in May anyway"

opps a logical error, no ice means sunrays directly warming the sea surface, until May, a significant warming impact . The corrector is corrected.

Kevin O'Neill

Cincinnatus writes: "...But they melt out in May anyway. This has no bearing on summer Arctic ice melt..."

It's always amusing when the clueless stop by and make sublimely silly statements. Cincinnatus ought to Google albedo, calculate the change in and area of reduced albedo, integrate over that the amount of solar insolation that will now be absorbed by the earth instead of reflected back into space, then get back to us with the numbers showing that the total change in energy will have no effect.

Or he can continue blindly stumbling along with uninformed views that only serve to makes us shake our heads and laugh. I actually prefer the latter - we need the occasional comic relief :)

Kevin O'Neill

Over in the Forum, Old Leatherneck writes:

Average JAXA Extent (2003-2014)
12-Apr 13,760,053
13-Apr 13,714,346
14-Apr 13,679,265 < - - - - - 5 Mar 15 13,664,797
15-Apr 13,638,698
16-Apr 13,593,635

It would appear that we are about 5 weeks ahead of where we should be!!

jdallen follows a bit later with a slightly more informed analysis than our friend Cincinnatus:

"Five weeks ahead sounds about right. The key is timing; we are running into increasing insolation with that running start, which has the potential to massively increase heat uptake in the region regardless of cloud cover. Keep in mind we are looking at nearly a million KM2 where the albedo has been cut from about .85 down to about .15; that's a rather large shift in energy budget, even on the periphery."

It may be too early to call the maximum, but if we have seen the maximum already, then there's a whole lot of energy that's going to be absorbed on top of the *already* reduced extent. Gee, sort of like an arctic feedback ... someone alert the scientists :)

Bill Fothergill

@ Jim,

As you rightly observe, the NSIDC daily did just drop by 107 thousand sq kms. On the other hand, there have been many lurches in either direction over the last 4 weeks.

Some notable upturns...
8Feb +131k, 15Feb + 82k, 21Feb +121k, 1Mar +101

Some downturns...
16Feb -98k, 17Feb -110k, 23Feb -83k, 27Feb -85k, 2Mar -89k

That's why I don't pay too much attention to the dailies. The Charctic 5-day rolling average smoothes out much of the wild see-sawing.

On the other, other hand (I'm rapidly running out of hands) the latest daily addition to the 5-day running figure is 228k lower than the one that's going to drop out tomorrow! So even the 5-day figure might lurch a bit.

On the other, other, other hand, going back to your comment elsewhere about a meeting with prospective parliamentary candidates - date and venue now logged - see you there!

BTW Does Christow have a pub called the Artichoke? If so, I've been there.

Cheers bill f

Espen Olsen

Dont waste your time guys, watch the facts!

Espen Olsen

BTW here is some of the facts:


Ladies and gentlemen, I would kindly like to ask you to continue this conversation in the latest blog post discussing this very event.


Bill Fothergill

@ Kevin

On the NSIDC Charctic rolling 5-day plot, last year's March 5th value was matched on the 27th March on the way back down.

However, things can really stagnate at this time of year. Back in 2010, the 5 day average for the 5th March wasn't beaten until the 8th April.

As we don't know how long it will take for any "surprises" around the maximum to work themselves out of the system, it could be a bit premature to characterise 2015 as being 5 weeks ahead of last year. I'm not saying that isn't the case, I'm just saying things could still stall for a goodly period.

cheers billf

Pete Williamson

"The big question now, of course, is whether the thinning will continue at this rate or slow down. Hopefully this will become clear in years to come."

Yep. For example the paper is about thinning ice doesn't say whether its melting or floating away. There is also no timeline so while we have the average rate of change there is no sense of variability over time. I'm doing something I generally really hate, which is to criticize a piece of science for what it doesnt contain rather than look at what it does. I guess Im greedy for the bigger picture answers.

Jon Hurn

I see the PDO has gone positive and NOAA has called El Nino.


No, Bill there is nothing there as I felt it a more dramatic response to Cincinnatus than a direct rebuttal.
FYI, I have read at least 85% of all posts and comments on this blog since Neven first published it several years ago. I teach high school so sometimes I get overwhelmed and am unable to post much or even read anything for a couple weeks sometimes months but I do get caught up. Maybe you do not recall any of my previous posts. I think it is a tremendous blog and is one of the bright spots educating the world on the serious of this issue. So, I hope you understand that was a supportive statement for this blog as I hope the others reading it did too.

Bill Fothergill

@ Vaughn

I fully endorse the comments you have made on this thread (and others). My most recent post to you started off as a bit of tongue-in-cheek banter, but it just sort of grew from there. (Hence my comment about considering doing it as as post in its own right.)

I did not for one moment think you were in any way attempting to denigrate Neven's blog. Any impression to the contrary is down to my idiosyncratic writing style.

mea culpa, mea culpa, mea maxima culpa


Thanks Bill, I was not sure, just making sure we were on the same page. Thanks for your support.

I think there were some valid/reliable papers that came out back in the 1960s and into the early 1970s about particulates and sulfur dioxide causing global cooling and that greenhouse gasses were balancing the cooling. It was, of course. quickly and accurately determined that these effects(human activity causes only NOT volcanic insertion into the stratosphere which might last a year or two) were very short lived....days-weeks or a few months at most..without continued human production. The other part of this was that as greenhouse gasses increased the net effects of sulfur and dust would diminish.

We still have sulfur dioxide and dust being produced in substantial quantities. Amazing how accurately it was predicted back in the 1960s how carbon dioxide(if it was continued to be produced from fossil fuels) would take over and so firmly control the "driver's seat."

Bill, I think your suggestion to Neven is pretty logical. Where are all of these reliable/valid papers that deniers appear to be referencing? I certainly can't seem to find them. (And if certain people read this comment, "reliable and valid" ARE the operative terms here. If you don't know what "reliable and valid" mean Mr. Webster might be a good place to start.)

Chris Reynolds

Comparison of PIOMAS and the Arctic Basin fit from Lindsay & Schweiger 2015.

Details at my blog.

Jim Hunt

Bill - Christow does indeed possess a pub called The Artichoke Inn. Sadly I have never partaken of a pint there.

However I do look forward to meeting you in the vicinity on the 24th!

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