Posts Tagged ‘Laptev Sea’


Arctic sea ice gone by 2015? A challenge to David Barber.

December 10, 2008
Here we go again. Last March I wrote about the media predictions that the Arctic sea ice would be gone by the summer of 2012. As I showed back then, those wild predictions were based on a simple extrapolation of the minimum summer sea ice extents of 2006 and 2007.


I’ll repeat the basic facts:

The sea ice area in the Arctic has been monitored by satellite for almost 30 years, since 1979. The area of the ice rises and falls, as you would expect, as the year cycles through its seasons. It reaches its yearly minimum by late September or early October. On the average, this minimum has been declining for the last 30 years. After October the northern sea ice area increases until it reaches a maximum in late March or early April each year. The yearly cycle is huge. Typically, about 60% of the total sea ice area melts away as is goes from yearly maximum to the yearly minimum.

The 2007 melt season was very severe and the Arctic sea ice area anomaly reached its lowest level since satellite tracking began.  But that low level was immediately followed by an unprecedented rise in sea ice area in the Arctic in the months following the 2007 summer melt season. The 2008 melt season was quite severe, but not as severe as the 2007 melt season. In order to go from the minimum ice extent of 2007 to zero ice in 2012, the Arctic sea ice extent minimum needs to drop an average of about 600,000 square kilometers per year. But the Arctic ended up with slightly more ice area (about 100,000 square kilometers more) after the 2008 melt season than after the 2007 melt season.  Figure 1, below sums it up.

Figure 1

Figure 1

New predictions of meltdown

Now along comes David Barber  from the University of Manitoba, who estimates that the Arctic Basin will be ice free by the summer of 2015. The Star Phoenix reports:

The ice that has covered the Arctic basin for a million years will be gone in little more than six years because of global warming, a University of Manitoba geoscientist said. And David Barber said that once the sea ice is gone, more humans will be attracted to the Arctic, bringing with them even more ill effects…He said he estimates the Arctic sea should see its first ice-free summer around 2015…Barber has said before the Arctic basin would be free of summer sea ice some time between 2013 and 2030. But their research about recent changes in the Arctic has allowed them to pinpoint the date even closer.

Barber sounds like a smart guy, and was the scientist in charge of a $40-million Arctic research project, the Circumpolar Flaw Lead System Study. He will present his preliminary findings at the International Arctic Change 2008 conference  in Quebec. However, his track record for predictions is rather spotty. Earlier this year National Geographic reported:

“We’re actually projecting this year that the North Pole may be free of ice for the first time [in history],” David Barber, of the University of Manitoba, told National Geographic News aboard the C.C.G.S. Amundsen, a Canadian research icebreaker.”

Prediction for summer of 2008 didn’t work out

The Arctic sea ice concentration reached its minimum around September 15th this year. Figure 2, below, from the Polar Research Group at the University of Illinois, shows the distribution of ice in the Arctic on that day. As you can see, the North Pole was not even close to being ice free. Figure 3 shows the Arctic Basin sea ice area for the last 365 days. Note that in mid-September the the sea ice area anomaly for the Arctic Basin was about negative 0.75 million square kilometers, but there were still 2.5 million square kilometers of ice yet to melt. Again, not even close to zero.

Figure 2

 Figure 2. Arctic Sea Ice Concentration on September 15th, 2008, when the Arctic sea ice reached its minimum for the year. Image from the University of Illinois Polar Research Group.

Figure 3. Figure 3. Arctic Basin sea ice area for the last 365 days.  In mid-September the sea ice anomaly was negative 0.75 million square kilometers, but there were 2.5 million square kilometers more than zero.  Image from the University of Illinois Polar Research Group.  Click on image to see clearer version. 

Those who like to parse words will note that National Geographic piece did not quote Barber as saying the “Arctic Basin” or the “Arctic Ocean” would be ice free during the summer of 2008.  They will correctly point out that he said “the North Pole.”  My answer to that is “So what.”  The North Pole has certainly seen open water in modern times, as attested to by the following images:
Figure 4.

 Figure 4. Skate (SSN-578), surfaced at the North Pole, 17 March 1959. US Navy photo courtesy of This image is from NavSource Online: Submarine Photo Archive

Figure 5.

 Figure 5. Seadragon (SSN-584), foreground, and her sister Skate (SSN-578) during a rendezvous at the North Pole in August 1962. Note the men on the ice beyond the submarines. USN photo from The American Submarine, by Norman Polmar. This image is from NavSource Online: Submarine Photo Archive


What about Barber’s prediction for 2015?

The December 5th StarPhoenix article mentioned above says that according to Barber, “The ice that has covered the Arctic basin for a million years will be gone in little more than six years because of global warming.”  I wonder if Barber can seriously believe that the Arctic Basin has been continuously ice covered for “a million years.”  There is considerable evidence  that the entire Arctic region was warmer just several thousand years ago than it is now. 

Open water from the northern coast of Greenland to the North Pole likely occurred in the not too distant past.  According to Science Daily, Astrid Lysa and colleagues have studied shore features, driftwood samples, microfossils and shore sediments from Northern Greenland. Science Daily reports:

 “The architecture of a sandy shore depends partly on whether wave activity or pack ice has influenced its formation. Beach ridges, which are generally distinct, very long, broad features running parallel to the shoreline, form when there is wave activity and occasional storms. This requires periodically open water,” Astrid Lyså explains.

Pack-ice ridges which form when drift ice is pressed onto the seashore piling up shore sediments that lie in its path, have a completely different character. They are generally shorter, narrower and more irregular in shape.

“The beach ridges which we have had dated to about 6000-7000 years ago were shaped by wave activity,” says Astrid Lyså. They are located at the mouth of Independence Fjord in North Greenland, on an open, flat plain facing directly onto the Arctic Ocean. Today, drift ice forms a continuous cover from the land here.

Astrid Lyså says that such old beach formations require that the sea all the way to the North Pole was periodically ice free for a long time.

“This stands in sharp contrast to the present-day situation where only ridges piled up by pack ice are being formed,” she says.

Funder and Kjaer reported similar results at the 2007 fall meeting of the American Geophysical Union. They point out that “Presently the North Greenland coastline is permanently beleaguered by pack ice…” but “that for a period in the Early Holocene, probably for a millennium or more, the Arctic Ocean was free of sea ice at least for short periods in the summer.” They date this time period to sometime between 8500 and 6000 years ago.  (Update 7/8/10 – Funder now believes “that multiyear sea ice was reduced to between half and a third of the present during the Holocene Thermal Optimum.”  Thanks to Kevin O’Neill and his persistence  in making this correction.)

An Open Challenge to David Barber

I am concerned about climate exaggerations and the effect  they have on public policy makers.  It seems quite clear that David Barber was off the mark when he predicted that “this year that the North Pole may be free of ice for the first time,” because neither the Arctic Ocean, the Arctic Basin nor the North Pole were ice free this past summer.  The North Pole being ice free is not that unusual, and the entire Arctic was probably ice free a relatively short 7,000 years ago.

Now Barber has made the slightly longer term prediction that “The ice that has covered the Arctic basin for a million years will be gone in little more than six years.”  I propose a friendly wager based on this prediction.  I will bet David Barber $1000(US) that the ice covering the Arctic Basin will not be gone anytime before December 31st, 2015.  The bet would involve no transfer of  cash between myself or Barber, but rather, the loser will pay the sum to a charitable organization designated by the winner.

 Definition of terms.  The Arctic Basin is defined by the regional map at Cryosphere Today.  “Gone” means the Arctic Basin sea ice area is less that 100,000 square kilometers, according to National Center for Environmental Prediction/NOAA as presented at Cryosphere Today .  Charitable organizations will be agreed upon at the time the bet is initiated. 

David Barber is a smart guy and evidently an expert in his field.  Taking on a wager with an amateur like me should be like shooting fish in a barrel.  I look forward to reaching an agreement soon.


Don’t Panic – The Arctic has survived warmer temperatures in the past

October 15, 2008

Since we are in the season of comparing charts, graphs and interpretations of the summer Arctic ice melt, it may be useful to pause and consider the history of Arctic temperatures in the Holocene.  There is an abundance of data compiled by hardworking field researchers over the years.  Before everybody got so excited about global warming, it was understood that the Arctic was considerably warmer in earlier parts of the Holocene than in the present.  The evidence for these warmer periods seems to have been forgotten in an age when satellite data causes us to fixate on the last thirty years.

I have collected a short list of papers that indicate times during the mid-Holocene, and places in or near the Arctic, when it was warmer than the present.  Some of these papers may also indicate warmer periods in the early or late Holocene, but I am concentrating primarily on the mid-Holocene in this post.  Figure 1, below, shows the spatial distribution of areas covered by these papers.  Click on the image to get a larger view.  Figure 2 shows the times in the mid-Holocene that each paper says it was warmer than the present.

Figure 1.  Numbers correspond to the journal articles that are listed below.  They also correspond to the numbered lines in figure 2.


 Figure 2.  “Paper #” corresponds to the numbered journal articles listed below.  The colored areas indicate the time periods in the mid-Holocene for which the papers indicate it was warmer than present.


The evidence that the Arctic was warmer in the mid-Holocene than it is now is compelling.  At longitudes almost completely encircling the Arctic, palaeological proxies of all kinds speak from the past with the same message.  Treelines moved in latitudes and elevations.  Alkenone molecules produced from sun loving organisms in the top layer of ocean water recorded the temperature of the water and settled into the depths of the ocean, depositing their temperature record in the sediments.  The pollens of various species of plants changed their ratios with changing temperatures and forest locations, drifted over lakes and settled to the bottom, leaving layer upon layer of temperature history.  Choronomid midges, small insects that live out their short lives in just a few weeks, varied their physiology according to the temperature of their environment, and carried their temperature stories to lake sediments. Forest plant species came and went at temperatures rose and fell, leaving behind their seeds in successive layers of soil as positive reminders that they had been there.

These proxies, and others, strongly indicate that the arctic region was warmer around 5,000 years ago than it is today.  Read the papers listed below to see the details.

Please feel free to criticize my interpretations of the papers, or to point out contradictory or complementary papers.


1. Jung-Hyun Kim, Norel Rimbu, Stephan J. Lorenzb, Gerrit Lohmanna, Seung-IlNam, Stefan Schoutene, Carsten Ruhlemannf, Ralph R. Schneiderg, North Pacific and North Atlantic sea-surface temperature variability during the Holocene, Quaternary Science Reviews, 23, 2004

Kim, et. al., used alkenone-derived sea-surface temperature records from sediments from over 30 locations to derive temperature changes in the Pacific and the Atlantic Oceans during the Holocene.  I have marked the locations of the five highest northern latitude cores, two above the arctic circle and three below it.  Kim’s data for these cores covers only the last 7,000 years, rather than the entire Holocene.  Nevertheless, the cores show temperatures clearly dropping to modern values over the last 7,000 years.  The northern-most core (75N) shows a temperature drop of 4.4 degrees C since 7,000 years ago.  Two other cores show temperature drops greater than 3 degrees C (3.3 and 3.8 degree drops at 57.8N, 8.7E and 57.7N, 7.1E respectively).  The remaining two cores show temperature drops of 1.8 and 0.6 degrees C.  Get copy here.

2. Kultti, S., et. al., Past changes in the Scots pine forest line and climate in Finnish Lapland: a study based on megafossils, lake sediments, and GIS-based vegetation and climate data,” The Holocene, Vol 16 No3, 2004b.

In this paper, Kultti, et. al., (2004b) looked at tree lines in Finnish Lapland and found “Results indicate that pine reached its maximum distribution between 8300 and 4000 cal. yr BP. The inferred minimum shift in mean July temperature was at that time c. +2.5.” Get copy here.

3. Solovieva, N., and Jones, V., A multiproxy record of Holocene environmental changes in the central Kola Peninsula, northwest Russia, Journal of Quaternary Science, 17(4), 2002. 

Solovieva and Jones studied a multi-proxy record of the Kola Peninsula in northern Russia and concluded that for the period from 8000 years ago to 5400 years ago “A maximum of forest cover and the high Pinus abundance during this period indicate the Holocene climate optimum. The multiproxy data from Chuna Lake generally agree with the temperature reconstructions based on the evidence from the Greenland ice-cores (Stuiver et al., 1995) and summer temperatures were likely to have been 2°–3 °C higher than at present.” Get copy here.

4. MacDonald, G., et. al., Radiocarbon dated Pinus sylvestris L. wood from beyond tree-line on the Kola Peninsula, Russia, The Holocene, Vol. 10, No.1, 2000.

MacDonald, et. al., dated Scots Pine wood (Pinus sylvestris L.) in Russia’s Kola Peninsula and found “the density of trees north of the modern tree-line was greatest between 7000 and 5000 BP.  Get copy here.

5. Sarnthein, et. al., Centennial-to-millennial-scale periodicities of Holocene climate and sediment injections off the western Barents shelf, 75°N, Boreas, Vol. 32, 2003.

Sarnthein, et. al., studied sediments on the Barents shelf and found “disappearing sea ice from 6.4–5.2” thousand years before the present, and again “3.0–1.6 kyr BP.” Get copy here.

6. Kultti, S., Oksanen, P., and Väliranta, M., Holocene tree line, permafrost, and climate dynamics in the Nenets Region, East European Arctic, Canadian Journal of Earth Science, Vol 41, 2004a.

 “Pollen, stomata, and macrofossils in a lake core with a basal date of 9700 14C BPwere used to reconstruct past changes in climate and vegetation in the arctic tree line area, northeast European Russia” … “We interpret summer temperatures to have been ca. 3–4 °C higher between ca. 8900 and 5500 BP than at present, and the lowest temperature regime of the Holocene to have occurred between 2700 and 2100 BP.”

7. V.L. Koshkarova and A.D. Koshkarov, RegionalSignatures of Changing Landscape and Climate of Northern Central Siberia in the Holocene, Russian geology and geophysics, N 6, v. 45, 2004

 Koshkarova and Koshkarov(2004) draw their conclusions based on “25 sections of Holocene deposits and soils of northern Central Siberia [that] were studied by paleocarpologicalmethods. Special attention was given to the reconstruction of the dynamics of speciation of forest cover in time and space.” These 25 sections are all above the arctic circle and range in longitude from 86 to 119°E. They divide the Holocene in the region into “intervals 9-8 ka (thermal maximum), 6.5-5ka (climate optimum – combination of higher temperatures and higher humidity), and 2.5-2 ka (thermal minimum).  Get copy here.

8. Robert A. Monserud, Nadja M. Tchebakova, and Olga V. Denissenko, Reconstuction of the mid-Holocene Palaeoclimate of Siberia using a bioclimatic vegetation model, Palaeogeography, Palaeoclimatology, Palaeoecology, 139, 1998

 Monserud, et. al., concentrated on the mid-holocene, which they defined as 4600 to 6000 years before the present. They found that during this period the Siberian winters “between 60 and 65N the palaeoclimate was 5.3 C warmer on average, and between 65 and 70N it was 7.7 C warmer.” For the warmer months the found “Summer was 2-5 C warmer than today between 63 and 73N, embracing much of the Northern Taiga, Forest-Tundra, and Tundra zones. A band of moderate summer temperature anomalies (0 – 2 C) is centered at 65N, and a second band of greater anomalies (2-5 C) is centered at 70N.” Get copy here.

9. Ilyashuk, E.A., Ilyashuk, B.P., Andreev, A.A.b, Bennett, K.D., Hammarlund, D., Hubberten, H.W., Chironomid-inferred Holocene mean July air temperatures for the Lena River Delta area, East Siberia, and the Kola Peninsula, northwestern Russia, ACSYS Final Science Conference,11-14 November 2003, Arctic and Antarctic Research Institute (AARI), St. Petersburg, Russia

 Ilyashuk, et. al. show that Radiocarbon-dated chironomid records from the lake Nikolay region of the Lena River Delta area “imply the warmest (up to 2-3°C warmer than nowadays) climate during ca. 10,200-9200 cal. yr BP…with two short warm oscillations (up to 8.9oC) at c. 5600 and 4500-4100 cal. yr BP…and a relatively long warm period ca. 2300-1400 cal. yr BP.” Get copy here.

10. Matul, A. G., et. al., Recent and Late Holocene Environments on the Southeastern Shelf of the Laptev Sea As Inferred from Microfossil Data, Oceanology, Vol. 47, No. 1, 2007.

Matul, et. al., (2007) from the Russian Academy of Science studied microfossils from the Laptev Sea, which is north of Siberia and well within the Arctic circle. They found that “Judging from the increased diversity and abundance of the benthic foraminifers, the appearance of moderately thermophilic diatom species, and the presence of forest tundra (instead of tundra) pollen, the Medieval warming exceeded the recent “industrial” one and is reflected in the near-delta sediments.” But they indicate that it was warmer even earlier by saying “..the warming in the Laptev Sea during the period of ~5100–6200 years B.P. corresponding to the Holocene climatic optimum could be even more significant as compared with the Medieval Warm Period.”

11. Lawson, D.E.,et. al., 2007, Early to mid-Holocene glacier fluctuations in Glacier Bay, Alaska, in Piatt, J.F., and Gende, S.M., eds., Proceedings of the Fourth Glacier Bay Science Symposium, October 26–28, 2004: U.S. Geological Survey Scientific Investigations Report 2007-5047, p. 54-55.

Lawson looked at glacial advances and retreats in Glacier Bay, Alaska. Glacier Bay is well south of the Arctic circle, but yields information about northern latitude climates. They found a glacial retreat starting 6800 years ago followed by a new glacial advance starting 5000 years ago. The retreat “was long enough to develop a mature forest” on land that was subsequently recovered with ice. Get cop here.

12. Kaufman, D. S., et. al., Holocene thermal maximum in the western Arctic (0-180°W), Quaternary Science Reviews, 23, 2004

In a very comprehensive study of the western Arctic Kaufman and coauthors from the US, UK, Canada, Norway, Iceland, and Russia (2004), studied proxies from over 140 sites in the western hemisphere part of the arctic. Their abstract notes “Paleoclimateinferences based on a wide variety of proxy indicators provide clear evidence for warmer-than-present conditions at 120 of these sites. At the 16 terrestrialsites where quantitative estimates have been obtained, local HTM[Holocene Thermal Maximum] temperatures (primarily summer estimates) were on average 1.6 ± 0.8 ° C higher than present…”
They devided the region into four zones, which I have labeled on the map.
12a. Central Eastern Beringia.Sketchy evidence indicates that the Holocene Therma Maximum occurred very early and had a short duration in this region. Temperatures were several degrees above current temperatures for some period between 12.8 and 7.1 ka. (mean initiation plus one sigma to mean termination minus one sigma).
12b. Northern Continental Canada.Better evidence indicates that this zone experienced higher temperatures from about 7.3 to 4.3 ka.
12c. Canadian Arctic Islands.Good abundant data that this zone was warm from 8.6 to 4.9 ka.
12d. Greenland, Iceland and other Artic islands.Temperatures were high in this zone from 8.6 to 5.2 ka.

13. Stewart, T. and England, J., Holocene Sea-Ice Variations and Paleoenvironmental Change, Northernmost Ellesmere Island, NWT., Canada, Arctic and Alpine Research, Vol 15, No. 1, 1983.

 Stewart and England examined more than 70 samples or Holocene driftwood on Ellesmere at 82° N Latitude. The time distribution of the driftwood indicates “prolonged climatic amelioration at the highest terrestrial latitudes of the northern hemisphere” from 4200 to 6000 years before the present.  Get copy here.

14. D. Dahl-Jensen, K. Mosegaard, N. Gundestrup, G. D. Clow, S. J. Johnsen, A. W. Hansen, N. Balling, Past Temperatures Directly from the Greenland Ice Sheet, Science, 282, 1998

“Dahl-Jensen, et. al., use borehole data to conclude “After the termination of the glacial period, temperatures in our record increase steadily, reaching a period 2.5 K warmer than present during what is referred to as the
Climate Optimum (CO), at 8 to 5 ka. Following the CO, temperatures cool to a minimum of 0.5 K colder than the present at around 2 ka. The record implies that the medieval period around 1000 A.D. was 1 K warmer than present in Greenland.” Get copy here