While Joe Romm and Mark Serreze bloviate about the current Arctic sea ice being “lowest in history”, science that doesn’t have an agenda (or paying thinktank) attached says otherwise:
“More importantly, there have been times when sea-ice cover was less extensive than at the end of the 20th century.”
From the Hockey Schtck: Paper: Current Arctic Sea Ice is More Extensive than Most of the past 9000 Years
A peer-reviewed paper published in the Canadian Journal of Earth Sciences finds that Arctic sea ice extent at the end of the 20th century was more extensive than most of the past 9000 years. The paper also finds that Arctic sea ice extent was on a declining trend over the past 9000 years, but recovered beginning sometime over the past 1000 years and has been relatively stable and extensive since.
Although it seems like a day doesn’t go by without an alarmist headline or blog posting obsessing over the daily Arctic sea ice statistics (and never about Antarctic sea ice extent which reached a record high this year), this paleo-climate perspective takes all the wind out of alarmist sails. Satellite assessment of sea ice conditions is only available beginning in 1979 (around the time the global cooling scare ended), with only sparse data available prior to 1979. The alarmists at the NRDC fraudulently claim in a new video that due to “climate destruction,” Arctic sea ice reached the lowest in history in 2010 (actually the low since 1979 was in 2007 and 2010 was the 3rd or 4th lowest depending on the source). Probably wouldn’t bring in many donations if they mentioned the truth: the 21st century has some of the highest annual Arctic sea ice extents over the past 9000 years.
The figure below comes from the paper, but has been modified with the red notations and rotated clockwise. The number of months the sea ice extent is greater than 50% is shown on the y axis. Time is on the x axis starting over 9000 years ago up to the present. Warming periods are shown in gray with the Roman and Medieval warming periods (RWP/MWP) notated, a spike for the Minoan Warming Period about 5000 years ago, and two other older & unnamed warming periods. The last dot on the graph is the end of the 20th century and represents one of the highest annual sea ice extents.
Holocene fluctuations in Arctic sea-ice cover: dinocyst-based reconstructions for the eastern Chukchi Sea Canadian Journal of Earth Sciences, 45: 1377-1397
Authors: J.L. McKay, A. de Vernal, C. Hillaire-Marcel, C. Not, L. Polyak, and D. Darby
Abstract: Cores from site HLY0501-05 on the Alaskan margin in the eastern Chukchi Sea were analyzed for their geochemical (organic carbon, d13Corg, Corg/N, and CaCO3) and palynological (dinocyst, pollen, and spores) content to document oceanographic changes during the Holocene. The chronology of the cores was established from 210Pb dating of near- surface sediments and 14C dating of bivalve shells. The sediments span the last 9000 years, possibly more, but with a gap between the base of the trigger core and top of the piston core. Sedimentation rates are very high (*156 cm/ka), allowing analyses with a decadal to centennial resolution. The data suggest a shift from a dominantly terrigenous to marine input from the early to late Holocene. Dinocyst assemblages are characterized by relatively high concentrations (600–7200 cysts/cm3) and high species diversity, allowing the use of the modern analogue technique for the reconstruction of sea-ice cover, summer temperature, and salinity. Results indicate a decrease in sea-ice cover and a corresponding, albeit much smaller, increase in summer sea-surface temperature over the past 9000 years. Superimposed on these long-term trends are millennial-scale fluctuations characterized by periods of low sea-ice and high sea-surface temperature and salinity that appear quasi-cyclic with a frequency of about one every 2500–3000 years. The results of this study clearly show that sea-ice cover in the western Arctic Ocean has varied throughout the Holocene. More importantly, there have been times when sea-ice cover was less extensive than at the end of the 20th century.
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| Arctic summer sea surface temperatures are also currently lower than much of the past 9000 years |
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As “Interesting Times” goes on, while we eat our pop-corn and comment at WUWT, the real icy issues will begin to take an equally more interesting perspective as your next winter time grows near.
Igloos anyone?
So, our carbon is interfering with nature’s trend towards ice-ball earth?
Thanks to whomever made the paper available.
Present conditions of polar temperature are several degrees below peak levels reached several times during the last million years. We have been in a cooling trend for about 10,000 years, but still remain well above average temperature. (Incidentally, CO2 has been rising through most of this cooling trend).
One more in a long series… History gives us lessons every day!
Ecotretas
Canucks rock when it comes to reasonable approaches to climate studies.
As some have posted on this site, the “beginning of the end” of the Holocene interglacial might indeed have been about 1-2 kYrs ago.
This does fit in with the climate record from the end of the last ice age when it was warmer than today.
No wonder, since the last interglacial was warmer than today for most of the time;
Greenland ice core says so:
http://i45.tinypic.com/2uzz32v.jpg
and instrumental record, which hints the Arctic ice was the same in 40ties
http://climexp.knmi.nl/data/icrutem3_hadsst2_0-360E_70-90N_n_mean1.png
and known events, like NW Passage open for shipping in 1942-44 just like in 2007-2009
This is all beginning to resemble one of those boxing matches where the hot young favourite is first knocked down, gets up groggy, dazed and reeling, and is then repeatedly hammered mercilessly by the old-timer until, staggering and bleeding, he collapses on the ropes. The last few posts on WUWT have been like a count-down to the end of the CAGW scam and we can all hope it’s carried out on a stretcher soon. Can’t you see the faces of the guys in the red corner? Seven, eight ……….
Thank you Anthony and all those others who have been the frontfighters in this struggle for the return of real, honest science.
Considering historical records about sea ice extent in the Arctic, this is not surprising at all. I’m sure, however, that the warmers will take exception to these conclusions.
The Titanic just hit an iceberg. Is Captain Smith, er I mean Captain Mann going to go down with the ship or is he elbowing his way to the lifeboats screaming that the data was bad.
Now that’s a shocker. Next, we’ll have a study about how recent warming isn’t unprecedented.
Bah, humbug. All those drowning polar bears beg to differ.
How did the poor cuddly wuddly polar bears survive all the time there was less ice? Did they learn to swim? Could today’s bears do the same? b
Or was nice Mr ex-Vice President Gore (Nobel Prize) doing a bit of scare mongering in his film?
The climate debate should always be framed in this sort of longer frame of reference.
Again, geologists & geoscientific research has much to add to the debate.
As a geoscientist, I have been skeptical from the beginning given the general lack of analysis on this time frame.
The peer reviewd journal “Rolling Stone” disagrees, says ice is disappearing at an alarming rate! “On Thin Ice: The World’s Two Great Ice Sheets Are Melting Faster Than Anyone Believed Possible” Of course the link I checked takes you to a Shania Twain article. Their web science is of course settled.
Nice to see a scientific article here again. Very interesting post, but I find it curious that the graph shows declining sea ice on a rising scale on the x-axis. “ka” means “per thousand years”, I assume? The use of dinocyst diversity and density provides a compelling methodology to support the conclusions, although I have not seen the data. This appears to be solid geological/paleontological paper. Of course, the implications are frightening, as it does sound as if we might be nearing the end of the holocene interglacial. Yikes!
Very interesting but not unexpected. I was talking with a retired scientist with the Geological survey of Canada this summer. In the area she studied she said that the tere were times when the temperature was at least 4 degrees C higher than present. I will try to find the published (peer reviewed paper) when I have a chance.
Interesting. The North West passage has been attempted but seldom completed as recorded at the British Library site
http://www.bl.uk/onlinegallery/features/northwpass/intro.html
and is still being attempted this year by Paul Allen of Microsoft;
http://megayachtnews.org/content/yachts/41-motoryachts/1858-octopus-superyacht-northwest-passage.html
Then of course we have the dichotomy of AGW ice loss assisting the potential extraction of arctic oil;
http://www.bbc.co.uk/news/world-europe-11395015
Yet it could be that the best chance of navigable waters has long gone and the next chance is far off. Mother Nature can be so cruel.
It seems that a knowledge of geological history is a necessity today. I don’t want anyone in our school systems, colleges and universities, and scientific specialities without some understanding of Earth’s processes and natural history. This requirement would certainly flunk the entire Climategate crew (CRU).
This was published in 2008. How come it took so long for it to be found?
I see our old friend the misleading baseline on the front chart there, the one that starts at “4” so it looks like 2007 almost saw a complete loss of ice. Sadly, too many people are incapable of even comprehending how they’re being led astray.
Incidentally, global temperatures are essentially meaningless when baseline is 0C. You need to drop that baseline by about 273 to put things in the proper context.
Slight change in topic, the introduction to the article said “(and never about Antarctic sea ice extent which reached a record high this year)” and I have noticed the recent rather fast drop in Antarctic ice in the WUWT Sea Ice page. I am really curious about this sudden drop and wondering why it is occurring following the record high extent. Seems to be some odd weather about recently.
When global cooling causes humans deaths to increase in serious numbers, who are the first to go? Is it just a matter of being close to the Arctic or Antarctic? Are there large populations on plateaus far from the poles that will suffer greatly? Anyone know?
It is interesting to note that the authors said that the trends in the Western Arctic Ocean were the opposite of those shown in the east. It is a kind of difficult paper to read, however, so I have just skimmed it. But it is not surprising that ice extent (actually SST’s) were higher around the time of the holocene optimum. At that time, because of orbital factors, the northern hemisphere received more insolation.
Of course this one will probably show up on poptech’s list of papers which disprove AGW.