Arctic Snow Depth, Ice Thickness, and Volume From ICESat-2 and CryoSat-2: 2018–2021

New paper and of course it’s worse than we thought.

New estimates of snow depth, from a combination of lidar and radar, improve sea-ice thickness estimates, according to a new study in AGU’s Geophysical Research Letters. Arctic sea ice has lost 16% of its thickness in the last three years, the study finds.
Credit: NASA/Kathryn Hansen

According to the press release:

– End-of-season Arctic multiyear sea ice is about 1.5 feet thinner in 2021 than in 2019

– Arctic Ocean sea ice lost one-third of its volume in the past 18 years

– New pan-Arctic snow depth suggests previous estimates of sea ice thickness may have been overestimated

https://news.agu.org/press-release/new-observations-from-icesat-2-show-remarkable-arctic-sea-ice-thinning-in-just-three-years

and

WASHINGTON—Over the past two decades, the Arctic has lost about one-third of its winter sea ice volume, largely due to a decline in sea ice that persists over several years, called multiyear ice, according to a new study. The study also found sea ice is likely thinner than previous estimates.

Seasonal sea ice, which melts completely each summer rather than accumulating over years, is replacing thicker, multiyear ice and driving sea ice thinning trends, according to the new research.

https://news.agu.org/press-release/new-observations-from-icesat-2-show-remarkable-arctic-sea-ice-thinning-in-just-three-years

And straight out of Rick’s Cabaret, I’m shocked I tell you.

“We weren’t really expecting to see this decline, for the ice to be this much thinner in just three short years,” said lead study author Sahra Kacimi, a polar scientist at the California Institute of Technology’s Jet Propulsion Laboratory.

https://news.agu.org/press-release/new-observations-from-icesat-2-show-remarkable-arctic-sea-ice-thinning-in-just-three-years

Here’s the paper.

First published: 10 March 2022 | https://doi.org/10.1029/2021GL097448

Abstract

Using ICESat-2 and CryoSat-2 freeboards, we examine the variability of monthly Arctic sea ice snow depth, thickness and volume between October 2018 and April 2021. For the 3 years, satellite-derived estimates captured a decrease in mean April snow depth (∼2.50 cm) and ice thickness (∼0.28 m) equivalent to an ice volume loss of ∼12.5%. Results show greater thinning of multiyear ice with an end-of-season thickness in 2021 that is lower by ∼16.1% (0.50 m), with negligible changes over first-year ice. For the period, sea ice thickness estimates using snow depth from climatology result in thicker ice (by up to ∼0.22 m) with a smaller decrease in multiyear ice thickness (∼0.38 m). An 18-year satellite record, since the launch of ICESat, points to a loss of ∼6,000 km3 or one-third of the winter Arctic ice volume driven by decline in multiyear-ice coverage in the multi-decadal transition to a largely seasonal ice cover.

Plain Language Summary

Ice thickness and volume are critical variables for assessing the evolution and response of the polar sea ice cover to a warming climate. Retrieval of sea ice thickness from altimeter freeboards (i.e., the vertical height of the floating ice and snow above the local sea level) requires knowledge of loading due to snow. Until recently, snow depth has been prescribed with a climatology based on historical field records. Using freeboard differences from ICESat-2 and CryoSat-2, we are now able to derive snow depth estimates. In this paper we examine the differences between climatological and satellite-derived snow depth as well as the retrieved ice thicknesses from the two altimeter missions. Their changes for three winters between 2018 and 2021 are documented. Derived ice volume estimates are placed within the context of an 18-year satellite record.

1 Introduction

As of December 2021, ICESat-2 has completed its 3-year prime mission (Markus et al., 2017) and is currently in extended operation. For the ice-covered Arctic Ocean, the lidar on the ICESat-2 observatory is tasked to provide the heights of sea ice and local sea surfaces for the calculation of freeboard—the vertical height of the floating ice above the local sea level. The retrieved total freeboard (snow plus ice) facilitates the estimation of thickness of the Arctic and Southern Ocean ice covers. The non-stop operations (with only a few interruptions) have provided all season coverage of the polar oceans. Here, we examine estimates of Arctic snow depth and ice thickness between October 2018 and April 2021.

Time-varying snow depth over sea ice, for computing snow loading, has been a limiting factor in the accuracy of sea ice thickness estimates. Prior to the launch of ICESat-2, the potential of combining ICESat-2 (IS-2) and CryoSat-2 (CS-2) freeboards to provide estimates of snow depth was recognized by Kwok and Markus (2017). The measurement concept is based on differencing the freeboards from IS-2 (which measures the height of the air-snow interface above the local sea surface) and CS-2 (which measures the height of the snow-ice interface above the local sea surface). For one Arctic growth season (October 2018 to April 2019), Kwok et al. (2020) provided a first examination of the snow depth retrievals using IS-2 and CS-2 freeboards. Results showed that the snow depths compared well with airborne estimates and spatial patterns of reconstructed snowfields. As well, the variability of the freeboards, derived snow depth, and ice thickness estimates was assessed in the Antarctic (Kacimi & Kwok, 2020).

In this paper, we examine the interannual variability of the freeboard-derived snow depth, ice thickness and volume over the first three winters of IS-2 operations (between October 2018 and April 2021). The paper is organized as follows. The next section describes the data used in this analysis. Section 3 briefly describes the two different estimates of snow depths used here – one from the IS-2 and CS-2 freeboards and the other from a modified Warren climatology (Kwok & Cunningham, 2015; Warren et al., 1999) – followed by an analysis of their spatial variability and seasonal evolution. In Section 4, we describe the calculated sea ice thickness and volume from IS-2 and CS-2, and the observed interannual variability. Section 5 summarizes the record of ice volume estimates since the launch of ICESat in 2003. The last section concludes the paper.

 https://doi.org/10.1029/2021GL097448

Read the full paper here.

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Tom Halla
March 12, 2022 6:09 am

Interesting techique. It is a pity it does not have a longer record.

Reply to  Tom Halla
March 12, 2022 6:23 am

Are griff and his “records” involved ?
😀

fretslider
Reply to  Krishna Gans
March 12, 2022 7:11 am

He may well be involved with saving Sequoia species….

“Giant sequoias are native to California, but due to climate change they are now classed as endangered, with just 80,000 left in North America, down by 98% from peak levels.

As California gets hotter and drier, it is predicted the sequoias will thrive more in the milder UK than the US by the end of the decade.”

https://www.mirror.co.uk/news/uk-news/grove-giant-sequoias-being-planted-26447432

I have questions about this project and few answers.

Last edited 6 months ago by fretslider
Gordon A. Dressler
Reply to  fretslider
March 12, 2022 7:17 am

Might logging for timber have anything—anything at all—to do with the decline of sequoias in North America?

Mike Dubrasich
Reply to  Gordon A. Dressler
March 12, 2022 8:36 am

Giant Sequoias are NOT a timber species, do not make good lumber, and are not logged. They do, however, burn in catastrophic forest fires [LINK]

“… the 2020 Castle Fire killed between 31% to 42% of large sequoias within the Castle Fire footprint, or 10% to 14% of all large sequoias across the tree’s natural range in the Sierra Nevada.”

I realize your comment was pure sarcasm, even though you didn’t use the tag. Obviously you love your timber framed home, much prefer it to a mud hut, and couldn’t care less about Arctic sea ice. Me too.

Gordon A. Dressler
Reply to  Mike Dubrasich
March 12, 2022 9:10 am

Mike, not quite the accurate historical story :

“The wood from huge old-growth giant sequoia trees does not make good lumber, despite the its resistance to decay, because it is brittle and has little strength. Nevertheless, sequoias were logged in the 1870’s and their wood was used for fenceposts and shake shingles . . . Young growth sequoias, unlike old growth sequoias, have wood properties similar to young growth redwood and is suitable for lumber.”
— source: https://ucanr.edu/sites/forestry/California_forests/http___ucanrorg_sites_forestry_California_forests_Tree_Identification_/Giant_Sequoia_Sequoiadendron_giganteum/ (my underlining emphasis added)

But I do stand corrected: I should not have referred to Giant Sequoias as previously having been logged for structural timber

BTW, I do care—and care deeply—about Arctic sea ice levels and trends. It’s just that I don’t believe the AGW/CAGW alarmists claims related to such.

Last edited 6 months ago by Gordon A. Dressler
Mike Dubrasich
Reply to  Gordon A. Dressler
March 12, 2022 11:04 am

Really? Your theory is that logging of Giant Sequoias in the 1870s caused Arctic sea ice to thin today? Unbelievable. Stunningly so.

And you care, deeply, about Arctic sea ice. Why? I don’t. Not one whit.

I care about 1,500 year old heritage trees burned up in predictable and preventable holocausts — caused not by gerbil worming but by absurdly ignorant and incompetent un-management perped by corrupt government agencies and their “expert” class of crony buffoons in scamademia.

Tell me how those trees survived for 1,500 years through all the climate perturbations until a year-and-a-half ago. Could it be that the current science paradigm of “virgin forests having a climax” in a steady state climate is Freudian psycho baloney?

Maybe the resident humans tending the landscape with frequent anthropogenic fire for millennia had something to do with Sequoia tree survival to incredible ages. Maybe modern humans are too self righteous to accept that ignorant savages (who didn’t even invent the wheel) were capable of far better forest management than know nothing Karens.

Gordon A. Dressler
Reply to  Mike Dubrasich
March 12, 2022 11:48 am

Mike, did I hit a nerve of yours?

Please re-read my above posts. I never mentioned any connection between the logging of Giant Sequoias and the thinning or Arctic sea ice . . . that is totally originated by you.

I just commented that the asserted reduction in Giant Sequoia (“down 98% from peak levels” in North America) as posted “fretslider” might be partially due to past logging activity by humans.

You independently brought up the subject that forest fires might also account for part of the asserted decline, which I agree with.

Also, you asked immediately above: “And you care, deeply, about Arctic sea ice. Why?” Short answer: Because a large amount of life on Earth is dependent on conditions in the Arctic and how temperatures in the Arctic drive both NH atmospheric circulation and NH ocean circulation (i.e., weather and climate). I live in Earth’s northern hemisphere.

There is no need for me to comment further on your philosophical musings and statements.

ex-KaliforniaKook
Reply to  Gordon A. Dressler
March 13, 2022 6:16 pm

Excellent response, Gordon. Mike is obviously not a student of California logging history. Of course, it is also possible that Sequoia National Park and others no longer present that history.

Amy
Reply to  Mike Dubrasich
March 12, 2022 9:32 am

I realize your comment was pure sarcasm, even though you didn’t use the tag. Obviously you love your timber framed home, much prefer it to a mud hut, and couldn’t care less about Arctic sea ice. Me too.

R. Morton
Reply to  Mike Dubrasich
March 12, 2022 4:30 pm

Sequoia trees NEED fire to survive. In the 1840s the frequency of fires in Sequoia habitat dropped dramatically due to human interference – perhaps that’s got something to do with their decline as well??

https://www.nps.gov/seki/learn/nature/giant-sequoias-and-fire.htm

tommyboy
Reply to  Mike Dubrasich
March 12, 2022 6:42 pm

They say a picture is worth a thousand words. The largest grove in Sequioa National Park is a grove of sawn stumps.

giant tree.jpg
Clyde Spencer
Reply to  Gordon A. Dressler
March 12, 2022 9:04 am

Old photo:

card00149_fr[1].jpg
Gordon A. Dressler
Reply to  Clyde Spencer
March 12, 2022 11:50 am

Thank you, Clyde.

As the saying goes, the Internet never forgets.

Last edited 6 months ago by Gordon A. Dressler
Amy
Reply to  Gordon A. Dressler
March 12, 2022 9:33 am

“… the 2020 Castle Fire killed between 31% to 42% of large sequoias within the Castle Fire footprint, or 10% to 14% of all large sequoias across the tree’s natural range in the Sierra Nevada.”

Derg
Reply to  Amy
March 12, 2022 11:49 am

Will they grow back?

TRM
Reply to  Derg
March 12, 2022 3:16 pm

Yes. It is fire that releases their seeds AFAIK

rah
Reply to  Amy
March 12, 2022 7:13 pm

That is because of the dumbasses not managing the fire hazard correctly. Sequoias are actually designed to survive a normal forest fire. In fact they must have fire to procreate because their cones don’t open without fire.

But mitigation efforts allow the deadfall to grow beyond what it naturally would before being consumed and the result is larger and hotter fires.

The Park Service has learned this and are now making controlled burns within the confines of their parks to prevent that kind of thing from happening.

Reply to  fretslider
March 12, 2022 10:16 am

I remember reading a National Park Service information at a sequoia grove in Yosemite. They emphasized how badly the sequoias needed forest fires to clear competing vegetation. They even speculated that maybe they grow so huge to attract lightning in order to start fires.

spren
Reply to  Curious George
March 12, 2022 1:49 pm

They also require the fires to cause their pine cones to open allowing the seeds to be planted in the soil.

Jeff Alberts
Reply to  Krishna Gans
March 12, 2022 8:08 am

If griff is the first thing you think of, then you really need to re-assess your priorities.

MarkW
Reply to  Tom Halla
March 12, 2022 12:09 pm

Actually, not having a longer record makes it more useful for the alarmits.

David Guy-Johnson
March 12, 2022 6:10 am

The study also found sea ice is likely thinner than previous estimates. Hmm, come back when you can say for certain one way or the other, instead of just hazarding guesses.

Ron Long
Reply to  David Guy-Johnson
March 12, 2022 6:54 am

I’m guessing, David Guy-Johnson, if you were the teacher and the student wrote in a report “…sea ice is likely thinner than previous estimates.” when it said in the report that there was some thinning up to now, you would grade the paper somewhere south of “C”.

Scissor
Reply to  David Guy-Johnson
March 12, 2022 7:41 am

As far as area extent is concerned, it looks like the maximum is in for 2022 and it’s higher than that from 1974 by about 400,000 km2 or more.

bdgwx
Reply to  Scissor
March 12, 2022 8:22 am

Area and extent are different. Which one are you referring to? What is your source?

David
Reply to  Scissor
March 12, 2022 10:27 am

Am I reading that correctly. The last year was 1987???

Scissor
Reply to  David
March 12, 2022 10:56 am

Yes, it covered the years 73-87 and was published in 1989.

bdgwx
Reply to  Scissor
March 13, 2022 6:09 am

Thanks. Unfortunately that is paywalled. So far the max for 2022 is about 14.88e6 km2. The 1981-2010 media is 15.52e6 km2 so 2022 is well below average. I looked at other extent reconstructions for the 1970’s and they all showed 1974 being well above 2022 for the winter max.

John Edmondson
March 12, 2022 6:14 am

I wouldn’t stand there.

TallDave
March 12, 2022 6:33 am

if this trend continues, humanity will be completely out of ice cubes by 2041

cocktails will have to use CO2 ice instead

sell your SUVs now sheeple

Last edited 6 months ago by TallDave
Gordon A. Dressler
Reply to  TallDave
March 12, 2022 7:20 am

To paraphrase a previous alarmist prediction: “By 2041 your children won’t know what it means to have ice cubes in beverages.”

Clyde Spencer
Reply to  Gordon A. Dressler
March 12, 2022 9:10 am

When I was working in the ice tunnel at Camp Tuto (Greenland), our work was interrupted several times by Danish airline pilots and stewardesses collecting clear ice from the walls of the tunnel for cocktail parties. They liked the ice because the entrained air bubbles would cause the ice to effervesce as it melted in their drinks.

Dave Fair
Reply to  Clyde Spencer
March 12, 2022 9:54 am

Clyde, did you collect any of the stewardesses to assist in making your drinks with the ice they grabbed?

rbabcock
March 12, 2022 6:50 am

US snow and ice website. https://nsidc.org/

David Dibbell
March 12, 2022 6:59 am

From the “Plain Language Summary” : “Ice thickness and volume are critical variables for assessing the evolution and response of the polar sea ice cover to a warming climate.”

From the PIOMAS update for February 2022: “The February time series (Fig 8) for both data sets have no apparent trend over the past 11 years.” (“Both” means CryoSat and PIOMAS.)

So if the Arctic ice volume trend has flattened out, we’re good, right?

http://psc.apl.uw.edu/research/projects/arctic-sea-ice-volume-anomaly/

 http://psc.apl.uw.edu/wordpress/wp-content/uploads/schweiger/ice_volume/ts_cryosat_piomas_current.png

M.W.Plia
March 12, 2022 7:05 am

For this study to be legitimate, if she is serious, author Sahra Kacimi needs to distinguish the natural from the unnatural and cover sea ice thickness and extent during previous warm periods, especially 1910-1945.
 
IMHO this will never happen as these people are just doing their jobs, which is padding the academic consensus narrative. Climate science is funding dependent so first principles can be overlooked.
 

Bruce Cobb
March 12, 2022 7:07 am

That’s funny, I don’t hear the arctic ice screaming. If it isn’t screaming there’s no catastrophe.

Scissor
Reply to  Bruce Cobb
March 12, 2022 8:51 am

It’s sighing over Irritable Alarmist Syndrome.

Brad-DXT
Reply to  Scissor
March 12, 2022 9:22 am

IAS – Irritable Alarmist Syndrome. I’m going to steal that, thanks. 🙂

b.nice
Reply to  Scissor
March 12, 2022 1:03 pm

Is that a precursor to Irritable Bowel Syndrome ?

Eben
March 12, 2022 7:12 am

“May have been” and “Likely” is the new scientific standards

Clyde Spencer
Reply to  Eben
March 12, 2022 9:12 am

Have they replaced “could” and “possibly?”

H.R.
Reply to  Clyde Spencer
March 12, 2022 10:00 am

I’ll stick with it likely could possibly be robust. Gotta work robust in there somewhere.

Gordon A. Dressler
March 12, 2022 7:14 am

Anyone else see the shell-game that is being admitted to in the above article’s very first sentence:

“New estimates of snow depth, from a combination of lidar and radar, improve sea-ice thickness estimates, according to a new study in AGU’s Geophysical Research Letters.”

So, here we have “estimates” being used to improve “estimates” . . . what could wrong with that?

IMHO, it would be much better to use scientific measurements to improve established scientific data.

Chalk up yet another brilliant statement to NASA’s science writer Kathryn Hansen.

Mr.
Reply to  Gordon A. Dressler
March 12, 2022 8:26 am

I estimate that your estimation of these improved estimates is probably approximately correct.

Chuck Kraisinger
Reply to  Mr.
March 12, 2022 8:50 am

Quite possibly.

H.R.
Reply to  Chuck Kraisinger
March 12, 2022 10:02 am

If they are robust estimates.

b.nice
Reply to  Chuck Kraisinger
March 12, 2022 1:05 pm

maybe.. perhaps.. if …..

H B
Reply to  Gordon A. Dressler
March 12, 2022 10:28 am

IMHO they are setting the scene to sell their new measurement technology

Rockphed
Reply to  Gordon A. Dressler
March 12, 2022 1:12 pm

Technically, any time an electromagnetic signal is decoded it is an estimate. So boo on the writers for being imprecise in their language. A better way to write would be “new radar and lidar measurements were combined to reduce the variance of estimates of sea ice thickness estimates.” However, that showcases that their previous estimates were not very precise, and that they probably do not even have a good handle on how imprecise they are.

Gordon A. Dressler
Reply to  Rockphed
March 12, 2022 1:49 pm

“Technically, any time an electromagnetic signal is decoded it is an estimate.”

Hmmm . . . that’s news to me. I thought one of the advantages of using binary coding for EM signaling (communication) was the certainty associated with the signal being either “on” or “off” . . . no ambiguity between the two. I realized that situation may breakdown in an EM-noisy environment, but that’s one reason that binary communications almost always have checksum encoding.

If instead you meant to refer to an electromagnetic signal output from a measurement device being an estimate due to a given number of bits being assigned to measurement resolution, then the word “estimate” is problematic. Yes, an “estimate” if one uses only, say, four bits resolution to measure what needs eight bits to be precise . . . but, no, if one uses, say, 32-bits resolution to measure what only needs eight bits to be consistent with the desired level of precision-of-measurement.

Last edited 6 months ago by Gordon A. Dressler
HotScot
Reply to  Rockphed
March 13, 2022 4:31 am

“We are guessing that…….”

Might be more precise.

stinkerp
Reply to  Gordon A. Dressler
March 12, 2022 2:58 pm

Also, why is anyone taking a 3 year observation of phenomenon supposedly related to climate seriously? It should be mocked with derisive laughter. Not that anyone should be surprised. Leftists always think they’re at the pinnacle of history, “discovering” what has never happened before; despite overwhelming evidence to the contrary. The foundation of all their alarmism rests on their monumental hubris and selection bias.

Remember that funny moment when the alarmists explained away the 17-year warming pause by assuring us that it had in fact happened before (which we all knew from looking at the historical record instead of burying our heads up the climate models)? That you need at least 30 years to establish a trend? Suddenly they “discovered” natural variability (that had always been there) when it bit them hard in the tenderloin district of their backsides. Just as suddenly, they revert to their doomsaying ways with a paltry 3 years of observations and complete ignorance of historical reports of Arctic ice variability. Leftists are nothing if not unstable in their ways.

Rainer Bensch
Reply to  stinkerp
March 13, 2022 3:06 am

What is a ‘short year’? Three of them is how long??

Ireneusz Palmowski
March 12, 2022 7:18 am

If anyone doesn’t understand how thin the troposphere is in winter at mid-latitudes, they should be in the southeastern US right now. Then he will understand how a total freeze can occur in a few hours.comment image

rbabcock
Reply to  Ireneusz Palmowski
March 12, 2022 7:45 am

Living in central NC, this morning is a great example of that. With the front coming through this morning, we will go from 60F to 21F by early tomorrow morning. With all the plants coming into leaf and flower, it is going to be a catastrophe.

Steve Case
March 12, 2022 7:25 am

The IPCC tells us that Nights, Winters, and the Arctic will see the effects of warming due to the greenhouse effect. (AR4 Chapter ten page 750)

Reading between the lines, the warming in the Arctic will be in the Arctic Winter, and that’s when the ice forms. Summers won’t get any warmer. Longer maybe, but not warmer. So if there is any reduction in sea ice extent, it’s not because summers are melting more ice, if there’s any reduction in Arctic ice extent it would be because of winter warming and forming less ice.

I suppose this is a well known scenario.

Here’s a link to a 2009 WUWT article that shows that the summer temperatures don’t change much:

DMI arctic temperature data animation doesn’t
support claims of recent Arctic warming

There’s a very good animation 1958-2009 that illustrates the point.

Last edited 6 months ago by Steve Case
Pat from kerbob
Reply to  Steve Case
March 12, 2022 8:05 am

So in winter at the pole it will be -40 instead of -45
Still forming ice

Chuck Kraisinger
Reply to  Pat from kerbob
March 12, 2022 8:52 am

-40 Celsius or Fahrenheit?

Nicholas McGinley
Reply to  Chuck Kraisinger
March 12, 2022 2:07 pm

Yes.

rbabcock
Reply to  Nicholas McGinley
March 12, 2022 3:39 pm

Only a few will get your comment.

Last edited 6 months ago by rbabcock
Steve Case
Reply to  Pat from kerbob
March 12, 2022 9:13 am

So in winter at the pole it will be -40 instead of -45
Still forming ice
___________________________________________

Will more ice form at -45? Common sense says so. But it may be one of those things, that beyond a certain point it doesn’t make any difference.

Besides all that, exactly how does sea ice extent affect anything all that much? Doesn’t affect me, and the bears don’t seem to mind as were told that there’s less ice, but there’s lots of evidence that the bear population hasn’t decreased. If it had decreased the press would be screaming about it and they are not. So if sea ice extent really is decreasing all it seems to be is evidence of warmer Arctic winters and, “So What?”

Rud Istvan
March 12, 2022 7:26 am

Summer Arctic sea ice remains at several Wadhams, unlike it’s predicted disappearance by Wadham. So shift to an unverifiable estimate of volume rather than a verifiable estimate of surface extent. Another neat trick like Mike’s Nature trick.

Gordon A. Dressler
Reply to  Rud Istvan
March 12, 2022 8:33 am

“. . . unlike it’s predicted disappearance by Wadham.”

Ummm . . . didn’t Al Gore co-opt that prediction on his way to co-winning the 2007 Nobel Peace prize?

The Norwegian Nobel Committee, responsible for selecting the Nobel Peace Prize laureates, must today be so very proud of that particular selection back then . . . NOT!

b.nice
Reply to  Rud Istvan
March 12, 2022 1:07 pm

“several Wadhams”

What is that, please?

Dave Andrews
Reply to  b.nice
March 13, 2022 10:50 am

Professor Peter Wadhams of Cambrige University made numerous predictions of Arctic ice extent falling below 1m square kilometres. Thus was born a ‘Wadhams’ or 1m sq kms of ice

fretslider
March 12, 2022 7:39 am

I stumbled on this by chance:

http://www.cpom.ucl.ac.uk/csopr/seaice.php – Centre for Polar Observation and Modelling Portal (University College London)

It’s CryoSat…

What irks me is the constant moving of the goalposts by alarmism inc

Weather isn’t climate – unless it’s a disaster of some sort. Then climate change, well, changes everything; and on a daily basis, weather depending…
Global warming causes colder winters
One paper syndrome (h/t D Nuccitelli)
Etc

So, let’s take single paper syndrome. This is a single study, therefore….

How to recognise this tactic

This tactic shows up when a person who has a vested interest in a particular point of view pounces on some new finding which seems to either support or threaten that point of view.

“Why do people use this tactic?
People use this tactic to try to convince you that the evidence supports their position.”

https://scienceornot.net/2012/10/23/single-study-syndrome-clutching-at-convenient-confirmation/

It works both ways.

Last edited 6 months ago by fretslider
DaveinCalgary
March 12, 2022 7:51 am

The Gore Effect at play here. Their study period is 2019, 2020, 2021 (really?!) but 2022 is proving to be a big increase in multiyear ice. Compare north of 75 degrees in Canada where most of the multi year ice traditionally forms. Several meters increase in thickness this winter compared to last year.

DMacKenzie
March 12, 2022 8:01 am

“Our new wide area LIDAR method gives different answers than the old borehole-and-measuring-stick method. And over 3 years of flying around huge areas of the planet, we got 5% less ice thickness each year. “ And the odds of throwing “heads” 3 times in a row is…..

Clyde Spencer
Reply to  DMacKenzie
March 12, 2022 9:35 am

Someone obviously had concerns about the sampling protocol used for years, particularly when extrapolated to the entire Arctic. What they have done is confirm that the former sampling protocol was flawed. They can only then speak to the changes that occurred in the last 3 years. The time period is too short to draw any conclusions about the Arctic climate.

Pat from kerbob
March 12, 2022 8:10 am

The way this becomes science is they then go out and do a bunch of boreholes over multiple years to check actual ice thickness vs the “estimate” of this new method.
At that point it becomes data
Today it’s just intellectual wanking.

Old Man Winter
March 12, 2022 8:27 am

I just love all the clowns- including Algore & Seth Borenstein- who
predicted the Arctic would be ice free:

https://www.climatedepot.com/2021/05/10/egg-on-their-faces-years-of-failed-arctic-sea-ice-predictions-by-scientists-al-gore-others/

https://realclimatescience.com/ice-free-arctic-forecasts-3/

BBBBBBBBwwwwwwwwaaaaaaaahhhhhhhhh!!!!!!!

Scissor
Reply to  Old Man Winter
March 12, 2022 9:14 am

The arctic is blowing a raspberry.

March 12, 2022 8:57 am

Ja. Ja. I told you what is happening or happened in the Arctic. Remember my name…

https://breadonthewater.co.za/2022/03/08/who-or-what-turned-up-the-heat/

Last edited 6 months ago by HenryP
March 12, 2022 8:58 am

“Arctic sea ice has lost 16% of its thickness in the last three years, the study finds.”

So the ice loses thickness while it gains ~3.6% more extent since 2018?

comment image

RobR
March 12, 2022 9:05 am

Question: if a 16% decline in three years is a product of climate change, should we not expect a corresponding 16% increase in sea water and air temperatures?

Warming in the past 100 years is not even remotely ose to 16%. Ergo, the study sucks, and or, other factors must be in play.

Walter Sobchak
March 12, 2022 9:17 am

Oh No! We’re All Gonna Die!

Dude1394
March 12, 2022 9:17 am

Let me try to get my head around the math. There has been a 1/3 loss of sea ice. And a pretty negligible rise in sea level as far as I know.

So when the other 2/3rds are gone we can expect what, an inch of sea level rise?

Smart Rock
Reply to  Dude1394
March 12, 2022 9:40 am

Please try to remember Archimedes’ principle

Dave Fair
March 12, 2022 10:06 am

CAGW is like Marxism: Every event proves it.

Robert Hanson
March 12, 2022 10:32 am

Our previous estimates of ice thickness turn out to have overestimated it, Our new estimates show it is thinner than our previous overestimates, which of course proves AGW is real.
Say what?

Matt G
March 12, 2022 11:22 am

The Arctic warming at the pole is behaving differently to the Antarctic continent due to the following reasons.

1) The Arctic is mainly ocean whereas Antarctica mainly land.
2) The Arctic has an ocean current (AMOC) moving through the middle of it whereas Antarctica (ACC) has an ocean current surrounding it.

Which warm or cools the quickest, ocean or atmosphere?

Answer = atmosphere

The atmosphere warms much quicker than the ocean so why was the Arctic warming significantly whereas there has been no or little warming in Antarctica?

The atmosphere can’t be doing this because this would had also happened in Antarctica where it is out of the influence from ocean currents. The warming from CO2 is not visible in the area where most warming should take place. Antarctica is the coldest and driest place on Earth so should have the most warming from the atmosphere if the control was changed from normal.

So what is the cause?

Answer = ocean current

The Antarctic Circumpolar Current (ACC) has very cold ocean water that circulates the continent preventing any warm ocean current from reaching it.

The Atlantic Meridional Overturning Circulation (AMOC) is a large system of ocean currents that carry warm water from the tropics northwards into the North Atlantic Ocean and eventually pass through the Arctic ocean.

If the Arctic was cut off from a warm ocean current it would also show no or little warming. Antartica would warm like the Arctic if it had a warm current directly influencing it.

So what should be expected by atmospheric warming only?

The Arctic would warm much slowly than Antarctica due to one being significantly moderated by water and the other being land based.

So what should be expected by ocean warming only?

Global cloud albedo has shown to have decreased by at least 4% between the 1980’s and 2000’s. This warms the oceans most where the highest solar energy penetrates the closest to the Tropics. Water moving north from the tropics is warmed the most, so when this flows into the Arctic ocean it warms the underneath of the floating ice surrounding the ocean surface. This has been occurring since the early 1980’s and is no coincidence that Arctic ocean ice has been declining since this period started.

Antarctica on the other hand the ocean warms the least with a decline in cloud albedo because the solar energy is considerably weaker closer to the poles. With no ocean current to move warm water towards it this option only applies. Therefore little or no warming over Antarctica and no sea ice decrease around it because this mechanism relies on warmer solar energy from the Tropics to provide the energy the Arctic has been receiving.

So what are the observatons showing over both poles, an atmospheric warming or an ocean warming?

Answer = ocean warming

This leads to a conclusion that there has been no signal at the poles of atmospheric warming and whatever there has been is within error.

Is no sea ice in Summer in the Arctic ocean a possible disaster that alarmists claim?

Answer = no

The melting of ice around the Summer season due to latent heat keeps the ocean surface very cold only slighly above 0c. If this was to occur, it would be only be for a very short time in Summer and ice would form quickly later at the end of the season. Surface ocean temperatures only need to drop around another 2c for freezing to return. Winter sea ice even from a Summer with no ice would return to similar area extents that have been seen for recent decades.

Joe Gordon
March 12, 2022 11:36 am

I suppose we had better take “action” because this undoubtedly means more ice tornadoes and jet-stream ice-melt bomb-vortex blasts.

MarkW
March 12, 2022 12:08 pm

Once again, the alarmists proclaim that the natural state of the world is for everything to stay the same from one year to the next, and if anything changes, it must be CO2 that caused it.

Derg
Reply to  MarkW
March 12, 2022 1:51 pm

This ^

Tom in Florida
March 12, 2022 12:34 pm

So, much like annual sea ice melt which reaches it’s peak near the end of Summer which is well past the peak of maximum insolation, would you expect most of the long term sea ice decreases to occur more near the end of the interglacial which would be well past the peak of the maximum temperature era?

Tom in Florida
Reply to  Tom in Florida
March 12, 2022 12:45 pm

After posting, I re-read my comments and realized I need to re-phrase it as such:
“much like the annual lowest sea ice volume occurs near the end of Summer which is well past the peak of maximimum insolation, would you expect the lowest sea ice volume years to occur towards the end of the interglacial”
And of course I am referring to northern hemisphere ice.

Dusty
March 12, 2022 12:41 pm

Here’s a question. If the new estimates show that ice is thinner than previous estimates, wouldn’t the older previous estimates be in error by a similar amount, such that everything was thinner and there has been, basically, no change?

ghl
Reply to  Dusty
March 12, 2022 5:14 pm

Dusty
They should have continued the old method to compare and calibrate. I wonder why they did not?

Steve Richards
March 12, 2022 12:44 pm

Oh dear! Satellites!

The following is from the technical files at this page:
https://icesat-2.gsfc.nasa.gov/science/specs

“91-day exact repeat orbit with monthly sub-cycle for the polar regions and oceans. Operational off-nadir pointing over land areas to generate a dense grid of data over 2 years”

It takes 91 days for the Satellite to get back to its starting point on the surface of the earth.

What has changed on the surface during those 3 months? Ice comes or goes or both?

Averaging lots of measurements of something that is changing gives you a number that means very little.

Not bad for climate change science.

Jim Gorman
Reply to  Steve Richards
March 13, 2022 5:13 am

Three months is a season the last time I researched it. I think both temps and resulting phenomena change a lot during that time.

lee
March 12, 2022 6:02 pm

The profiles provide a consistently referenced elevation data set with unprecedented accuracy and quantified measurement errors that can be used to generate GCPs with sub-decimeter vertical accuracy and better than 10 m horizontal accuracy.”

https://ntrs.nasa.gov/api/citations/20100026470/downloads/20100026470.pdf

So accuracy of about 100mm.

rah
March 12, 2022 7:20 pm

Well you gotta figure they would come up with something like this because extent has been pretty good the last couple years. In fact this winter it got pretty close to Iceland.

So know how they have operated in the past it is reasonable to expect them to come up with a “study” that claims that ice is thin, rotten, no good ice.

HotScot
March 13, 2022 4:36 am

Probably a dumb question, but where has all this melting ice gone?

Surely there should be a considerable, and noticeable, rise in sea levels.

Chris Norman
March 13, 2022 9:03 am

As the annual maximum arctic ice has been growing since 2015 they have to make it thinner.

ATheoK
March 13, 2022 1:03 pm

“a new study in AGU’s Geophysical Research Letters. Arctic sea ice has lost 16% of its thickness in the last three years, the study finds.”

Not a neutral source.

Their findings appear to me, modeled using personal opinions.

“Arctic sea ice snow depth is estimated, for the first time, from a combination of lidar (ICESat-2) and radar (CryoSat-2) data. Using these estimates of snow depth and the height of sea ice exposed above water, the study found multiyear Arctic sea ice has lost 16% of its winter volume, or approximately half a meter (about 1.5 feet) of thickness, in the three years since the launch of ICESat-2.”

“Scientists make satellite estimates of sea-ice thickness using snow depth and the height of the floating ice above the sea surface. Snow can weigh ice down, changing how ice floats in the ocean. The new study compared ice thickness using new snow depths from satellite radar and lidar to previous ice thickness and snow depth estimates from climate records. The researchers found using climatology-based estimates of snow depth can result in overestimating sea-ice thickness by up to 20%, or up to 0.2 meters (0.7 feet).”

Estimates of estimates compared to believed erroneous earlier estimates… From the linked paper; “The researchers found using climatology-based estimates of snow depth can result in overestimating sea-ice thickness by up to 20%, or up to 0.2 meters (0.7 feet).

Their approach to determining ice height above sea water sounds remarkably like NOAA’s satellite measurements of sea level. They radar and Lidar sea ice, then estimate how high the ice is, smoothing out irregular surfaces. From this they calculate subsurface ice and total ice volume…

The author’s opinion summarizes the lack of quality behind this research.

” The study also found sea ice is likely thinner than previous estimates.”

Such confidence and precision hints at huge error bounds that are not displayed or cited.

Last edited 6 months ago by ATheoK
Jules
March 14, 2022 1:18 am

The study makes two claims: 1. Arctic sea ice is thinner than thought, and 2. It is losing volume faster than thought.

But if 1 is correct then 2 can only be relative to the Adjusted(TM) thinner baseline. At 3yrs long this is clearly an insufficient reference period to enable meaningful conclusions to be drawn, even if everything else in the study is correct.

In this regard, given the researchers involved have seen fit to publish conclusions arising from such an extremely short measurement series, this hardly encourages confidence in the extent of rigour underlying the rest of the research.

michael hart
March 21, 2022 2:44 pm

There is always one statistic to p
ick from many to prove what you want. Isn’t it called the green jelly bean hypothesis?

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