NASA and multi-year Arctic ice and historical context

Over at NASA, they have a press release about old Arctic sea ice disappearing since 1980, including a helpful comparison widget that splits the before and after for comparison. I’ll run it in full below followed by comments.

NASA Finds Thickest Parts of Arctic Ice Cap Melting Faster

This interactive illustrates how perennial sea ice has declined from 1980 to 2012. The bright white central mass shows the perennial sea ice while the larger light blue area shows the full extent of the winter sea ice including the average annual sea ice during the months of November, December and January. The data shown here were compiled by NASA senior research scientist Josefino Comiso from NASA's Nimbus-7 satellite and the U.S. Department of Defense's Defense Meteorological Satellite Program. Credit: NASA/Goddard Scientific Visualization Studio.

› View 1980 image

› View 2012 image

GREENBELT, Md. — A new NASA study revealed that the oldest and thickest Arctic sea ice is disappearing at a faster rate than the younger and thinner ice at the edges of the Arctic Ocean’s floating ice cap.

The thicker ice, known as multi-year ice, survives through the cyclical summer melt season, when young ice that has formed over winter just as quickly melts again. The rapid disappearance of older ice makes Arctic sea ice even more vulnerable to further decline in the summer, said Joey Comiso, senior scientist at NASA Goddard Space Flight Center, Greenbelt, Md., and author of the study, which was recently published in Journal of Climate.

The new research takes a closer look at how multi-year ice, ice that has made it through at least two summers, has diminished with each passing winter over the last three decades. Multi-year ice “extent” – which includes all areas of the Arctic Ocean where multi-year ice covers at least 15 percent of the ocean surface – is diminishing at a rate of -15.1 percent per decade, the study found.

There’s another measurement that allows researchers to analyze how the ice cap evolves: multi-year ice “area,” which discards areas of open water among ice floes and focuses exclusively on the regions of the Arctic Ocean that are completely covered by multi-year ice. Sea ice area is always smaller than sea ice extent, and it gives scientists the information needed to estimate the total volume of ice in the Arctic Ocean. Comiso found that multi-year ice area is shrinking even faster than multi-year ice extent, by -17.2 percent per decade.

“The average thickness of the Arctic sea ice cover is declining because it is rapidly losing its thick component, the multi-year ice. At the same time, the surface temperature in the Arctic is going up, which results in a shorter ice-forming season,” Comiso said. “It would take a persistent cold spell for most multi-year sea ice and other ice types to grow thick enough in the winter to survive the summer melt season and reverse the trend.”

Scientists differentiate multi-year ice from both seasonal ice, which comes and goes each year, and “perennial” ice, defined as all ice that has survived at least one summer. In other words: all multi-year ice is perennial ice, but not all perennial ice is multi-year ice (it can also be second-year ice).

Comiso found that perennial ice extent is shrinking at a rate of -12.2 percent per decade, while its area is declining at a rate of -13.5 percent per decade. These numbers indicate that the thickest ice, multiyear-ice, is declining faster than the other perennial ice that surrounds it.

As perennial ice retreated in the last three decades, it opened up new areas of the Arctic Ocean that could then be covered by seasonal ice in the winter. A larger volume of younger ice meant that a larger portion of it made it through the summer and was available to form second-year ice. This is likely the reason why the perennial ice cover, which includes second year ice, is not declining as rapidly as the multiyear ice cover, Comiso said.

=========================================================

One of the most often complained about things from icy fanatical folks like Tamino (aka Grant Foster) and Neven Acropolis on their blogs is “cherry picking”.

Generally, cherry picking claims are applied when you pick a section out of datasets, and use that short section to draw a conclusion. For example, over at Steve Goddard’s blog he has nice multi-year sea ice plot from NSIDC where he’s suggesting the short term gain in 2 and 3 year old multi-year ice is significant against the larger down trend.

ScreenHunter 64 Mar. 01 01.52 NASA Caught Lying Again

The ongoing loss of 4 and 5 year old ice would tend to confirm the premise of the NASA article.

But I want to expand the scope a bit. For the first time in history, starting about 1980 with the advent of satellite remote sensing, we have geophysical data we’ve never had before. The trouble is, that 30+ year period from 1980-2012 is just barely over a 30 year climate normals period. We don’t know what sea ice extent and age trends were before that, as there really aren’t any good data on the Arctic ice pack prior to 1980.

For example if you visit the Wikipedia page Polar Ice Packs, you won’t find anything about historical sea ice data prior to that, but plenty about recent declines. They do though have a century scale model from 1950 to 2050 that posits a loss of thickness.

I’m not sure where they got that high resolution data for 1955, since we didn’t have any satellites then (Sputnik launched in 1957 and had no remote sensing capability, only a radio beacon beeper so you could track it) and we didn’t have under the ice submarines (to measure ice thickness) then either as the USS Nautilus (SSN-571) was the first vessel to complete a submerged transit beneath the North Pole on August 3, 1958.

Even the USS Skate (SSN-578) didn’t surface at the North Pole through the ice until 1959. Here’s that photo again that drives Tamino and Neven crazy when they see it because it shows open water in the Arctic in 1958:

Skate (SSN-578), surfaced in the Arctic August 1958. US Navy photo

From John Daly: (added)

For example, one crew member aboard the USS Skate which surfaced at the North Pole in 1959 and numerous other locations during Arctic cruises in 1958 and 1959 said:

“the Skate found open water both in the summer and following winter. We surfaced near the North Pole in the winter through thin ice less than 2 feet thick. The ice moves from Alaska to Iceland and the wind and tides causes open water as the ice breaks up. The Ice at the polar ice cap is an average of 6-8 feet thick, but with the wind and tides the ice will crack and open into large polynyas (areas of open water), these areas will refreeze over with thin ice. We had sonar equipment that would find these open or thin areas to come up through, thus limiting any damage to the submarine. The ice would also close in and cover these areas crushing together making large ice ridges both above and below the water. We came up through a very large opening in 1958 that was 1/2 mile long and 200 yards wide. The wind came up and closed the opening within 2 hours. On both trips we were able to find open water. We were not able to surface through ice thicker than 3 feet.”

Hester, James E., Personal email communication, December 2000

More here

So where does NOAA get 1955 high resolution data on Arctic sea ice thickness? One wonders. Wikipedia cites the source as http://www.gfdl.noaa.gov/visualization-gallery but when you go there, there’s no record of the plot. Even when you go to the page at GFDL for the graphics used in IPCC’s AR4, you don’t find this visualization anywhere, nor do they have any data prior to 1980 to visualize with.

In fact it seems the Wikipedia source page is the only place that 1955-2055 visualization exists anymore. Perhaps it has been deep-sixed at NOAA after somebody pointed out the folly of it like I did with another visualization blunder from the same group.

Back to the main point.

You can plot, model, and visualize all you want, but there’s just no good sea ice thickness nor extent data prior to 1980 when satellite remote sensing came on the scene, yet we do have anecdotal evidence of previous Arctic ice retreats. For example, this now famous report from 1922 that first appeared in the Washington Post.

changing-artic_monthly_wx_review_intro.png

Sailing all the way to 81° 29 minutes North. That sure beats the Catlin expeditions and the recent Row to the Pole (which never actually made it to a pole of any kind).

In fact, so little ice has never before been noted.

But do we have any Arctic wide data for 1922? No. We also don’t have any Arctic wide data for the Little Ice Age (LIA), The Medieval Warm Period (MWP), Dark Ages Cold Period (DACP) and the Roman Warm Period (RWP). We do however have temperature reconstructions from Ljungqvist (2010) like the one below:

Reconstructed extra-tropical (30-90°N) mean decadal temperature variations relative to the 1961-1990 mean of the variance-adjusted 30-90°N CRUTEM3+HadSST2 instrumental temperature data of Brohan et al. (2006) and Rayner et al. (2006), showing the approximate locations of the Roman Warm Period (RWP), Dark Ages Cold Period (DACP), Medieval Warm Period (MWP), Little Ice Age (LIA) and Current Warm Period (CEP). Adapted from Ljungqvist (2010).

These alternating warm/cold periods, in Ljungqvist’s words: (Source CO2 Science)

“probably represent the much discussed quasi-cyclical c. 1470 ± 500-year Bond Cycles (Bond and Lotti, 1995; O’Brien et al., 1995; Bond et al., 1997, 2001; Oppo, 1997),” which “affected both Scandinavia and northwest North America synchronically (Denton and Karlen, 1973)” and have “subsequently also been observed in China (Hong et al., 2009a,b), the mid-latitude North Pacific (Isono et al., 2009) and in North America (Viau et al., 2006), and have been shown to very likely have affected the whole Northern Hemisphere during the Holocene (Butikofer, 2007; Wanner et al., 2008; Wanner and Butikofer, 2008), or even been global (Mayewski et al., 2004).”

Now it could be argued strongly that since we are in the Current Warm Period (CWP) and Arctic Sea Ice is on the decline, and the rise of the machines in the industrial age coincides with that, that man has the greatest influence on Arctic Sea Ice. That may be, but we just don’t know. We have no good ice data prior to 1980. We do however have suggestions that much of Earth’s climate and responses to it (like Arctic sea ice) is cyclic.

And with only just over 30 years of good sea ice data, how does one determine if this downturn isn’t just part of a regular cycle? For all we know, we may be simply looking at one part of a larger cycle. In fact, a recent peer reviewed paper says “there appear to have been periods of ice free summers in the central Arctic Ocean” in the early Holocene, about 10-11,000 years ago

In that larger context, using 30 years of Arctic sea ice data to draw conclusions and model out to 2050 might very well be viewed as an exercise in cherry picking.

Suggestions by NASA in 2007, in Smedsrud Et Al 2011 and recently in Wang, Song, and Curry suggest that wind patterns are a big factor in the Arctic puzzle. There’s also direct evidence that soot from the industrialization of Asia is collecting in the Arctic and could be a factor in albedo changes in the Arctic which contribute to ice loss.

Sea ice is a complex problem, and my personal view is that we simply don’t know enough about its behavior in the larger context to demonstrate a causal relationship with the recent global temperature increases.

And speaking of global, then there’s that pesky Antarctic, which has an upward trend in sea ice area:

Image from Jeff Condon via his Air Vent blog.

And then of course, unless you believe Steig’s (2009) application of Mannian statistical madness, there’s no evidence that Antarctica has any statistically significant temperature trend. That claim has been disproved by O’Donnell et al 2010.

Global sea ice hasn’t varied all that much in 30 years, and I for one, am just not all that worried about it. Especially since the Great Pacific Climate Shift occurred right about the start of the satellite data, and you all know what our friends tell us about starting conditions.

Image above from this excellent essay on The Air Vent

You can track sea ice in the NH and SH on WUWT’s sea ice page.

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richard

Just recently i have been looking through the NSIDC website , it is very interesting and they explain ice melt and increase and tie it into natural weather conditions,
eg- The past two Arctic winters were dominated by a negative phase of the Arctic Oscillation, a large-scale weather pattern that brings generally warm conditions to the Arctic and colder conditions to Europe and North America.
their press releases etc are a different matter, there they push the agw line but worded carefully,

More Soylent Green!

Who first coined the phrase “determining a trend from just one data point?” Essentially, that’s what we have here, just a small amount of data that’s being extrapolated out over a period of time, as if the short-term trend is going to continue forever. The timeline for the data is just too short.
There’s no historical context, either, as the rest of the post indicates.
Finally, evidence of global warming does not prove it’s anthropegenic.

AFPhys

I continue to be haunted by the recollection of an item I ran across about a decade ago:
In diaries of Marco Polo, there is a statement that he sailed to a location where he observed the Pole Star in the South. That means he was on a line between true north and magnetic north, since he was using lodestone compass. That, in turn means he had sailed the Arctic Ocean from Japan nearly all the way to Greenland.
It sounds to me like Marco did not encounter a whole lot of ice, if any at all.

Andrew

So does this mean the polar bears will start eating all the penguins if the ice keeps melting?
…also, anybody ever charted volcanic eruptions and ice thickness to see if there is any correlation…and perhaps even some causation? Since 1980 the have been some big ones in the tropics, but nothing like Krakatoa. St Helens is getting closer, but Iceland and Alaska are belching pretty regularly and they divert airplanes to avoid the ash…I am just wondering

TG McCoy (Douglas DC)

Cousin’s husband was a young torpedoman on the Skate when they did that…
there was a LOT of open water…

Nerd

Thanks for the reference to peer review paper about Arctic being ice-free during the summer 10,000 years ago. That would come handy when discussing with others about ancient Egypt civilization at that time (Atlantis?) when Pyramids, Sphinx, etc may have been built much earlier than widely believed.

Steve from Rockwood

Multi-year ice “extent” – which includes all areas of the Arctic Ocean where multi-year ice covers at least 15 percent of the ocean surface – is diminishing at a rate of -15.1 percent per decade, the study found.

This will be easy to prove as 50% of the ice in 2011 will be gone by 2015. I am not a believer.

Steve from Rockwood

Whoops. 2041. Mis-read. Just when I thought they had stopped with their 30 year projections (one career long)! Sorry.

Dave Wendt

I’ve posted this video from Ignatius Rigor a number of times

It is an expansion on the ideas developed in this paper

The red dots shows the current location of buoys used to estimate the age of sea ice. The areas of older, thicker ice are shown in white, while younger, thinner sea ice is shown as darker shades of blue.
This animation of the age of sea ice shows:
1.) A large Beaufort Gyre which covers most of the Arctic Ocean during the 1980s, and a transpolar drift stream shifted towards the Eurasian Arctic. Older, thicker sea ice (white ice) covers about 80% of the Arctic Ocean up to 1988. The date is shown in the upper left corner.
2.) With the step to high-AO conditions in 1989, the Beaufort Gyre shrinks and is confined to the corner between Alaska and Canada. The Transpolar Drift Stream now sweeps across most of the Arctic Ocean, carrying most of the older, thicker sea ice out of the Arctic Ocean through Fram Strait (lower right). By 1990, only about 30% of the Arctic Ocean is covered by older thicker sea ice.
3.) During the high-AO years that follow (1991 and on), this younger thinner sea ice is shown to recirculated back to the Alaskan coast where extensive open water has been observed during summer.
The age of sea ice drifting towards the coast explains over 50% of the variance in summer sea ice extent (compared to less than 15% of the variance explained by the seasonal redistribution of sea ice, and advection of heat by summer winds).
If you concentrate on the change in the drift paths of the buoys the paradigm shift in the surface circulation patterns that Rigor and Wallace refer to is very apparent

Gary

In terms of ice coverage that reduces heat transfer between water and air, does it make much difference whether the baby ice is one foot thick or the great-grandpa ice is ten feet thick?

Dave Wendt

Oops I double posted the video rather than linking this paper
http://iabp.apl.washington.edu/research_seaiceageextent.html

Allan M

So we have annual ice, biennial ice and perennial ice. Can we grow any of these in an ordinary garden? Or a CO2-enriched greenhouse?
But Oh, the wonders of drawing straight lines on graph paper.

There always seems to be a little bit of truth in the alarmists’ pronouncements. Is not black soot a major influence upon Arctic ice melt? Also subterranean vocalic activities are a known factor? Has NASA quantified and factored these and other similar causes of ice melt into heir models? I doubt it.

Gil Dewart

It would be interesting to see if there is a connection to the opening of the Russian Northern Sea Route in the 1930s.

Owen in GA

You cover it very well. 30 years is a painfully short time in geologic time.

DirkH

NOAA is a shady bunch. Anyone know their real mission?

Anything is possible

I can’t help wondering whether they got their 1955 volume by calculating the observed trend in ice volume between 1979 and the present, plugging it into their model, and back-projecting on the assumption that the observed trend remained unchanged between 1955 and 1979.
Sound about right?

JJ

That NASA graphic that Anthony reproduces to lead the article is very misleading.
It shows different halves of the NH for each of the two years being compared. The half it shows for the “high ice” 1980s is the half that has the overwhelming majority of the ice in all years. The half they are showing for the “OMG Global Warming” present is the half that has very little sea ice in any year, as it has very little sea. Apples to oranges.
Not that there hasn’t been a reduction in prerennial sea ice, but that is a very misleading graphic that doesn’t show the true extent of the issue.
Why does NASA do things like this.

Andrew

@More Soylent Green!
To your point Mr Green…
The fun one can have with data points, charts and historical stock and mutual fund performance…
In most cases it is illegal as well as being very unethical. But it does get done at times. Usually in an attempt to DUPE people…and get them to believe in what you are saying…so they give you their hard earned money…just ask Bernie Madoff…
So…is it ironic…Madoff is pronounced Made off…as in somebody made off with our money… Al Gore has told us all a fancy allegory, which in turn fueled the money machine that has Made Off with all our money…but Al is smarter than Bernie, because VP Al avoids the SEC via the UK…OKAY
But that is for the $ thread…this thread is about playing games with charts and graphs…
Maybe the Climate Guys can include in their charts and graphs certain disclaimers such as…
“Past performance is no guarantee of future results.”
Caveat emptor…modern translation: Be skeptical

Dave Wendt

In regard to my comment above, I have been following the daily Arctic sea ice drift maps for some time and it appears to me that the surface circulation patterns established in the late 80s are changing again in the last couple years, although they don’t seem to have stabilized into new paradigm as yet. The drifts do seem to be slowing the flows out through the Fram, which might partially explain the short term increases in the sea ice age that Goddard noted

bertief

Sadly I have reached the point now where if anyone of Hansen’s goons were to present me with something that looked like a duck and quacked like a duck, I would reckon it could only be a rat in a duck suit.

crosspatch

“The ongoing loss of 4 and 5 year old ice would tend to confirm the premise of the NASA article.”
Actually, if you look at that chart, we should be due for a significant increase in 4yo ice next year. That is to be expected. If you look at the 3yo ice from 2010 to 2011, there was a significant increase. That should translate to an increase in 4yo ice in 2012 and in 5yo ice in 2013. I think overall we are in good shape. 2008 + 5 years = 2013 so we can’t start recovering the 5yo+ ice until 5 years after the first ice season after the 2007 anomaly. So 5+ ice can not possibly start to recover until 2013 because ice formed in 2008 won’t be 5yo until then.

Green Sand

Barrow Sea Ice Day 61 – Mar 01, 2012, 08:30 AM AKST:
Air temperature:
-36 °C, -32 °F
Ice thickness:
1.37 m, 4 ft 5.5″
1.37m not met until Day 90 in 2011
http://seaice.alaska.edu/gi/observatories/barrow_sealevel

Martin

The USS Skate picture you show was taken in 1958 (not at north pole).
REPLY: Yes I have the date year wrong, fixed thanks, Wikipedia suggests the photo is at the North Pole:
http://en.wikipedia.org/wiki/File:USS_Skate_at_North_Pole_-_0857806.jpg
This may be of interest from John Daly:
For example, one crew member aboard the USS Skate which surfaced at the North Pole in 1959 and numerous other locations during Arctic cruises in 1958 and 1959 said:
“the Skate found open water both in the summer and following winter. We surfaced near the North Pole in the winter through thin ice less than 2 feet thick. The ice moves from Alaska to Iceland and the wind and tides causes open water as the ice breaks up. The Ice at the polar ice cap is an average of 6-8 feet thick, but with the wind and tides the ice will crack and open into large polynyas (areas of open water), these areas will refreeze over with thin ice. We had sonar equipment that would find these open or thin areas to come up through, thus limiting any damage to the submarine. The ice would also close in and cover these areas crushing together making large ice ridges both above and below the water. We came up through a very large opening in 1958 that was 1/2 mile long and 200 yards wide. The wind came up and closed the opening within 2 hours. On both trips we were able to find open water. We were not able to surface through ice thicker than 3 feet.”
– Hester, James E., Personal email communication, December 2000

Susan Corwin

This is sorry, even you’ve consumed some of the koolaide:
“30 year climate normals period”
As anyone on the “waste” coast knows: the minimum climate cycle is the PDO: 60 years,
and then there is the AMO.
Since no one can predict solar activity for even this maximum, much less SC25 or SC26, anyone who is truly honest, would have to use, at least, one solar micro cycle of 177 years as the
“time for a climate normalization”.
I have to view anything else as bluster, and as the expression goes,
should you want to use short term results, then “gleick you”.

RobW

lets see if I get this right. After years of a cooling globe (1940-1970’s) we say the level of Arctic ice is “Normal” then after thirty more years of slightly warmer globe we say see the normal ice is disappearing. OK got it.

Not Interested

Life in the Holocene is so easy we argue about ice being lost. What frivolous mental masturbation it is to cry about the cold and to complain about warmth. I think we need an ice age to stop the nonsensical ‘we actually know what’s happening’ chatter. Besides, what would life be without new challenges? Come on nature!

Rob Crawford

“In diaries of Marco Polo, there is a statement that he sailed to a location where he observed the Pole Star in the South. That means he was on a line between true north and magnetic north, since he was using lodestone compass. That, in turn means he had sailed the Arctic Ocean from Japan nearly all the way to Greenland.”
Or he ran through some sort of magnetic anomaly. Think “Iron Bottom Sound”, but natural.

‘Sea ice is a complex problem, and my personal view is that we simply don’t know enough about its behavior in the larger context to demonstrate a causal relationship with the recent global temperature increases.”
Well, it’s hard to deny physics. And the physics and observations about warming SSTs around the arctic suggest that warmer SST is a contributor. Its not like warmer SSTs will cause an increase in ice. Do other factors–wind and soot– play a role? Of course. Do warmer SSTs play a role? of course. is the final figure determined soley by one of them? of course not.
It’s probably more accurate to say that many factors, including increasing SST temperatures, play a role in the diminishing ice. Were there ice free periods in the warm parts of the Holocene?
Probably. Was soot from industrial processes around? probably not 10K years ago. Warmer planet, heat moves polarward. heat moves poleward.. less ice than there would be otherwise.
Kinda hard to argue that we were ice free in the warm holocene, but that now there is no causal relationship whatsoever between warming planet and diminishing ice.
So, is it getting warmer? yup. will that result in there being less ice in the north than there would be otherwise? yup. Is all of the loss directly a consequence of the warming? no there are other factors. Did C02 cause it all? no. The ice at the pole is retreating. Warming plays a role. Co2 plays a role in that warming. The debate should be centered on how much warming and what if anything we can do about it and what should we do.
REPLY: and then there’s Antarctica, an opposite anomaly all by itself. Bipolar disorder me thinks – Anthony

We should not forget that in the usual way, Arctic sea ice melts when it disappears. Some of it is carried out of the Arctic Ocean by the wind, but usually this is a small amount. In 2007, an unusual weather event occurred, with high pressure developing over Canada, and low pressure over Russia. The strong winds generated by this weather pattern blew large quantities of old ice into the Atlantic Ocean, where it melted. July 1st 2007 was the day when the sea ice decreased by the maximum amount recorded. How unusual was this event. We dont know. We do not have enough in the way of histrorical data. But, part of what this study has found, can be explained by this unusual event, and there are signs that the old ice may be recovering. For example, the figure September Ice Age 1983 to 2011 shows a recovery of 2 and 3 year old ice. Yes, we simply dont have enough data.

Bloke down the pub

Most days I take a look at the sea ice ref page. I haven’t been able to confirm it, but I’ve got a suspicion that the Noaa/Ebrl graphic for Northern hemisphere surface temperatures has changed it’s colour coding. Is anyone able to put me out of my misery by showing where I can find archived graphics to compare it to?

Sun Spot

Regarding arctic ice “high resolution data for 1955” reference on wikipedia, are you telling me Willy Connoley let inaccurate data slip onto wikipedia ?
I am being sarcastic of course.

BioBob

Come on, Steve Mosher. You are going to tell us all how GREAT the data is, right ? All those fabulous sea surface temperatures from Argos and satellites accurate to .00000000000000001 degrees, with gazillions of replicates all the way back to 12,000 BC right ? [Never mind that 451 degree Lake Michigan]
Give.Me.A.Break.
Exactly what is the big rush ? IS the planet going to turn into a glowing cinder next year or in a decade ? Perhaps it would be wise to do the science first and then draw the conclusions, neh ?
Step one would be to take the proper observations using the proper sampling regime or not bother at all. The current data is so bad and even if you think it adequate, taken for such a short period that any conclusions drawn bear more resemblance to reading entrails than real science.
“A Good Man Always Has to Know His Limitations”

Coach Springer

“Co2 plays a role in that warming. The debate should be centered on how much warming and what if anything we can do about it and what should we do.”
I’m not a scientist or contributor to the science anyway anywhere, but can’t the debate also be about what role CO2 – not “CO2 has a role so what if anything can we do about it”? As orignally stated above, by all means, let the international conferences decide what to do about CO2 since it’s problem is conceded. The orginal statement sounds like The Accidental Warmist.
I may be – no I am – a scientific dolt. But I’m pretty damned sure that it’s been warmer and colder with higher and lower levels of CO2 and the role of CO2 is not adequately defined in relation to known and unknown variables. Dolt that I am, I am also the one who will have to pay the price for the outcome of the debate and, hopefully, may get to vote in a way that affects the outcome of the power play – I mean debate. Right now, I remain unconvinced to surrender my natural gas furnace, SUV, lawnmower, electricity rates, grocery bill, showering habits, ect. to the care of Al Gore and Jim Hansen as a higher power.

Spence_UK

So we had a single data point – very low ice in 2007.
In 2008-2009, when ice was recovering, they couldn’t point to the current ice because it was recovering. So what did they do? Wail about the multi-year ice. The multi-year ice has reduced! Oh no! We’re doomed etc.
Trouble is, by 2012 the multi-year ice is starting to recover as well. So what do they point at? Oh no! The 5-year old ice is at a low point!
OF COURSE IT IS THERE WAS A MINIMA FIVE YEARS AGO.
Sorry for shouting, but do they really think they can get away with this? If there is a local minima in year X, and current year is Y, there will be a minima in (Y-X) year old ice currently. It isn’t exactly rocket science.

Alcheson

Why they just take core samples of the ice at various points all over the ice cap? They could establish the age of the ice at any place of concern and then estimate ice coverage versus age over the whole area. Problem is, they would probably find that there is no very old ice anywhere and instead would establish that the North Pole was free of ice in the not to distant past, which is exactly NOT what they would want to find.

Allen C.

Of course this is all because of man made CO2. Without that tiny bit of extra CO2 in the atmosphere, the Arctic Ice Cap would be somewhere near Churchill Falls Nfld, right?

@Steven Mosher says:
The ice at the pole is retreating. Warming plays a role. Co2 plays a role in that warming. The debate should be centered on how much warming and what if anything we can do about it and what should we do.
======================
Why do you want to do anything about it Steve? Why does it matter? Two thirds of the ice melt every year for a few months at the peak of summer anyway. If a little more melts during that period why would anyone care? Do our societies really having nothing better to worry over? This is the nature of fads I suppose, and the latest fad is climate science.

Ice from early 1980s to mid 1990’s may contain more volcanic ash
http://www.vukcevic.talktalk.net/EAA.htm
Just a thought.
Steven Mosher says:
………….
Hi Steven
Thanks, I have been rehabilitated on RC.
( http://www.realclimate.org/index.php/archives/2012/03/unforced-variations-march-2012/comment-page-1/#comment-229334 )

DesertYote

Anyone else catch the last paragraph?
“This cycle is reminiscent of one occurring on the opposite pole, known as the Antarctic Circumpolar Wave, which has been related to the El Niño-Southern Oscillation atmospheric pattern. If the nine-year Arctic cycle were to be confirmed, it might explain the slight recovery of the sea ice cover in the three years after it hit its historical minimum in 2008, Comiso said.”
If the trend is to the “good” its natural cycles, and they are covering up the bad. If the trend is “bad” then its worse then we thought its all mans fault and we need to do something NOW.

Andrew

Anthony, regarding your Skate comments…
Note the lack of specificity given by the submariner…Uncle Sam does know the exact locations and the exact depth of the ice…and for years they kept this a secret, due to National Security concerns. I cannot think of a valid excuse for this information not to be public. The Russian’s most assuredly have better info today than we had in the 50’s and 60’s. Heck, we have declassified the fact that we Howard Hughes salvaged a Commie sub…and last I checked…state of the art submersibles are not being readily manufactured…in any of the more sandy regions of our globe…so no threats from any peace loving peoples either…speaking as a card carrying Infidel…
I would think someone should request the details of Sea Ice in the 1950’s from the Department of the Navy…maybe…

u.k.(us)

Great post, Anthony.
A return to the roots of our current understanding, such as it is.

I see somebody has already referenced William Michael Connolley’s name; this would be the first place I would start (no sarc) on this subject:
In fact it seems the Wikipedia source page is the only place that 1955-2055 visualization exists anymore.
.

Green Sand

Steven Mosher says:
March 1, 2012 at 11:26 am
“Well, it’s hard to deny physics.”

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Arctic very interesting this year, Barents and Kara sea ice has struggled to get established and the North Atlantic SSTs have shown positive anomalies throughout the freeze period, well up to now they have.
The North Pacific SSTs have however recorded significantly negative anomalies and the Bearing and Chukchi Sea ice is so far showing an increase in extent and thickness over last year.
http://weather.unisys.com/surface/sst_anom.gif
The melt season will be interesting to watch.

rw

If as they claim there’s continual thinning, then sooner or later the minimal ice extent is going to have to start falling in a serious way. Or am I missing something? (Or does thinner ice melt more slowly as the temperatures rise?)
So when will we see an ice-free Arctic? Or have they given up being that specific?

richard verney

Steven Mosher says:
March 1, 2012 at 11:26 am
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I find myself agreeing with much of what Steven says, save that I would say that CO2 may play a role in the warming. Anthony is right to point out that the Antartic is not behaving in a similar fashion, and this just goes to emphasise the effects of natural variability.
As regards Artic ice loss, the real issue is so what?
Does the ice loss have any significant impact on Albedo? Probably not much.
Does increase ice loss help cool the planet? Probably yes.
Is thin 1 year ice as effective as 3 or 5 year ice at trapping ocean heat? Probably yes.
Is there any need to be concerned about Artic ice loss? Probably not.
Is Artic ice loss likely to be beneficial? Probably yes.

SteveSadlov

Unless there is broad use of some type of radioisotope tracking, I really question any characterization of a particular “pixel” of ice as being 1, 2 or n year. How on earth could that ever be tracked within an ever shifting plastic and “tectonic” mass, with new accrual and accretion, “obduction” of slabs over each other with subsequent fusion, snow pack accumulating on top and “glaciating” to the overarching mass, melt ponds later refreezing, etc, etc, etc.
I question the whole enterprise of ascribing an “age” to any particular ice “pixel.”

John F. Hultquist

Susan Corwin says:
March 1, 2012 at 11:11 am
About “normal”
Since the mid-1930s there has been an established international agreement to calculate “normal” temperature and precipitation using a 30-year average. After a year ending in zero (0) a new set of “normals” is calculated and used until another decade has passed. The idea was to provide a simple basis for comparisons that folks could personally relate to.
For example, go to the link below and you can see three periods, namely 1961-1990, 1971-2000, 1981-2010. These are shown on the left side. The table on the right shows 1948-2012 for a summary. The computer era has changed things some but when a TV or radio station reports the weather they will be comparing the day’s numbers to the 1981-2010 period.
http://www.wrcc.dri.edu/cgi-bin/cliMAIN.pl?wa7473

Rosco

Can someone explain why a space agency studies Arctic ice ??

G. E. Pease

RobW says:
March 1, 2012 at 11:20 am
“lets see if I get this right. After years of a cooling globe (1940-1970′s) we say the level of Arctic ice is “Normal” then after thirty more years of slightly warmer globe we say see the normal ice is disappearing. OK got it.”
The submarine pictures in open Actic water during the fifties indicate that the ice may have been less than “normal” then as well!