Never has such a high sea ice extent been observed in the North Atlantic as in summer 1917 (Fig.3). This exceptional case has never been investigated. Worst! Science seems not to have taken notice of it although thorough understanding of the event could possibly answer two important questions concerning climate change:
FIRST: Contribute the late icing and subsequent melting process to the sudden extraordinary warming at Svalbard and polar region (Fig.2 & 3) since winter 1918/19?
SECOND: Contribute naval war around Great Britain since 1914 to the exceptional icing?

Fig. 1; March 1917	Fig. 2; April 1917	Fig. 3; May 1917	Fig. 4; July 1917

Although air temperatures at Svalbard fell to all time record low in winter 1917, sea ice conditions in March were usual (Fig. 1). In general annual sea ice extent is highest in April, but succeeded average already in April, Fig. 2; rising to a level by end of May, which presumably has not happen for more than 200 years or longer, Fig.3. Even in late July the sea ice remained at a unusual high level, Fig.4. This late and extensive icing process may have had a pronounced impact and ocean water structure, from sea level to may hundred meter depth, which could have influenced the most significant climatic change in the 20th Century, namely the Arctic and Northern Hemisphere warming that started 18 months later in winter 1918/19 (Fig. 5, 6 & 7)..

Fig. 5; Svalbard, T°C, seasons & annual	Fig. 6; Annual T°C north of 70°1900-2013 + Fig.15

The sudden temperature increase at Svalbard commented the Norwegian scientist B.J. Birkeland in 1930: “In conclusion I would like to stress that the mean deviation (at Svalbard, Fig. 5 & 7) results in very high figures, probably the greatest yet known on earth” . Indeed, in any way exceptional. The significance for the entire Polar region is shown in Fig. 6 (15 & 16) indicating the annual. According I. Schell (1956) such a situation may not have been duplicated earlier for 200 years and more (Fig. 8). It seems that the year 1866 is regarded as the most severe ice year (Fig. 9), but that relates to April while the case 1917 is in May/June.

Fig.7, Svalbard T°C annual means	Fig.8, I. Schell (1959) said:	Fig.9, Extreme sea ice years

What contributed naval war in Europe since August 1914? In summer 1916 the naval war machinery entered a new dimension. Sea mines, sub-marines, torpedoes, depth charges, aerial bombing, were produce an masse and used. Now almost 5-10 merchant ships sunk every day. All water from SW Wales/UK and North Sea travelled northwards with an impact on the sea surface and ocean structure down to many dozen meters, Fig. 10-13.

Fig.10	Fig.11	Fig.12	Fig.13

Exactly at the same time the summer season got a sea ice extent never observed and 1 ½ years later the biggest temperature jump in the Northern North Atlantic and adjacent sector in the Arctic ever observed (Fig.14).

1. First QUESTION: What was the role and impact of navel war on the sea ice situation in the North Atlantic in summer 1917?
2. Second QUESTION: What was the role and impact of summer sea ice on the ocean structure in the high North in winter 1918/19?
3. Third QUESTION: What was the role and impact of naval war in Northern European waters on the Norwegian and West Spitsbergen Current and subsequently ocean structure between August 1914 and November 1918?

The correlation between warming in the Arctic and naval war is evident. It seems time to investigate and prove it.

Continue reading:
http://www.seaclimate.com/i/i.html
http://www.arctic-heats-up.com/chapter_8.html

Fig. 14; Main area of warming between 1920 and 1939	Fig. 15 & Fig. 16

By Arnd Bernaerts
Full text in PDF: HERE (1 MB)

Reference Part II: The previous Arctic warming started in winter 1918/19, in the sea area between Spitsbergen and Fram Strait. This important fact was established in a recent paper titled: “The start of the previous Arctic warming 90 years ago”, while the discussion of the causation of this event was announced to be done in a subsequent paper. By reference to the previous paper it is regarded as an established fact that the Arctic winter warming from
1919 to 1940 (EAW) was caused and sustained by the sea (see: Causation I & II), which does not answer the question of causation: Was it natural variability, or did human activities contributed? As neither the reason, nor the mechanism is known, it was suggested to discuss it separately (Causation III). The following discussion is taking up the thread and trying to bring more light to the most interesting aspect, whether an anthropogenic element had been a part of causing the early Arctic warming (EAW). Fig.13

Figure 1 to 12 refer to the previous paper.
Figure 13 to 25 are related to this paper.
Details in the figures in the annex

Introduction: Analysing the causation and mechanism for the EAW faces two fundamental problems, which the interested reader should be aware of. On the one hand the acknowledgement of the influence of the ocean on all atmospheric processes is still in an infancy stage. How many people and scientists consider weather and climate matter in the relevant dimension between a sea water and an air column, which is in cubic-meter 3 to 10’000. This means, that one degree temperature taken from the 3 cbm water volume, the atmosphere above, over 10 kilometres, can be warmed by one degree. If the air surface layer over 100 metres has a humidity of 100%, the one degree from the 3 cbm water-column could inject into the layer the amount of 100 degree. On the other hand for the Arctic in the early 20^th Century there are virtually no direct observation available, very few air temperature data series, and not any on ocean temperatures, neither from the sea surface, nor from any lower sea levels.

However, few, but very important circumstances are established and build the foundation for the further analysis:

1. The First World War (WWI) lasted from August 1914 to November 1918. Since summer 1916 naval war activities and effectiveness increased significantly due to new weapon systems and mass production.
2. The Arctic temperatures (north of 70°N) between 1915 and 1917/18 were particularly low ( Fig. 3, 4, and 13). North Europe experienced a very cold winter 1916/17, which was the third coldest in Great Britain during the last century¹.
3. A highly unusual sea icing in the North Atlantic occurred in summer 1917, when for the only time in 110 years (1901-2010) the ice covered all sea area off Spitsbergen in April, thereon extended far south in May and June, and only retreated in July 1917 (Fig.9-12, and 24).
4. Record high increase in winter temperature on Spitsbergen in the winter 1918/19, which sustained for two decades. (Fig. 7 and 21)

While the close timing of the four events within a very short time period is self-evident, it is not immediate obvious that their interdependence is also very close. From a geographical point of view it looks as if the mentioned events, which cover a sea area from the English Channel, along the Norwegian coast up to the Fram Strait with a bit more than 2000 kilometres (Fig.14), but with the regard to the sea this distance does not exist. In practical terms of oceanology the distance between Scotland and Spitsbergen is zero, as by far the most of all sea water which was once around Great Britain, reaches the front garden in the west of Spitsbergen, within a small time lag of a couple of weeks or several months.

Fig. 14; Major naval battle areas	Fig. 15; U-Boat activity area

 

The initial making of the EAW is not a global issue, and it is neither a North Atlantic issue, but related to a small corridor in the east of the northern North Atlantic (Fig.16), which function more like a single spot, rather than a long geographical stretch due to the permanent flow of a current in only one direction, from south to north, from the UK to the Arctic Ocean (Fig.8 and 16). Fig.16

The possible nature of causation. Although we have some strongly correlated events it does not tell very much about the causation, or as presumably required in our case, about the chain of causation. On the other hand there is no causation without correlation, and what should not be ignored, that the more strings and circumstances are pointing into one direction, the more it is rectified to take any correlation serious. That is what good science should be all about. Unfortunately earth science is far away from acknowledging fundamental aspects, which would have made it much easier to present the case. Although it would make little sense to include them in the later reasoning, they shall at least be mentioned briefly:

• Long term average weather (climate) is the blue print of the ocean. The influence is a matter of the conditions of the water column (e.g. heat and salinity), and a time factor.  For a full investigation of the mentioned events, one would presumably need may millions data along the stretch from the English Channel to the Atlantic section of the Arctic Ocean. There are extreme few sea surface data available, and none from lower sea levels.

• Until now science has very little knowledge of what kind of human activities at sea (e.g. shipping, fishing, offshore platform) might have an impact on atmospheric conditions. Even naval war activities, which is a very sudden, and forceful penetration in the marine environment, has not reached science.

• Neither can any benefit be drawn from the fact, that the First World War and the Second World War (WWII) came up with a number of similar weather pattern in Europe, as science has done irresponsible little research in this respect. That becomes evident if one takes note of an observation by A.J. Drummond at the Kew Observatory (London) published in 1943:  “Since comparable records began in 1871, the only other three successive winters as snowy as the recent ones (1939/40, 1940/41, and 1941/42) were those during the last war, namely 1915/16, 1916/17 and 1917/18, when snow fell on 23%, 48% and 23%, of the days, respectively”².

If meteorology and oceanology would have done sufficient observation and research on each of the three mentioned subjects, the question what actually caused the EAW would presumably have been answered since long: the ocean and naval war contributed, by a small, medium, or by a big margin.Â

A brief chronology of four years naval war. Â
Four years naval war can not be pressed in one brief paragraph. However it should be recognised that a naval war of the magnitude of WWI has a much more serve dimension as other ocean uses over comparable or even much longer time periods. A particularly decisive factors is the suddenness, and the intensity over considerable depths with regard to the temperature, and salinity structure. This are the two main factors of concern, while any other kind of interference, e.g. by pollution, is not subject of this analysis, as it is, for me, completely out of reach to quantify and verify its relevance.
August 1914 to Autumn 1916: The first two war years are presumably irrelevant for initiation of the EAW toward the end of the war. The sea areas affected were the Baltic Sea, the route to Murmansk, and all waters around Great Britain (Fig. 14 & 15). What interested meteorologist could have realised that it was not difficult to observe that bigger naval encounter immediately influenced the local weather conditions, from good visibility to mist, dust, fog, or rain due to moving from ‘hither and thither’ and shelling. For example it happened off the coast of Scarborough on the 16^th of December 1914, and during the biggest sea battle ever, the Jutland Battle close to the Skagerrak, on 30 May and 01 June 1916, about Winston Churchill brilliantly narrates in his book “The World Crisis 1911-1918″ (p. 251-272, and 599-651).

Fig. 17, Sea Mines general situation in 1918	Fig. 18, Sea Mines, “Northern Barrage”, since April 1918

 

Autumn 1916 to November 1918: The naval war machinery went in full gear since summer 1916, due to new weaponry and mass production.  From now to the end of 1917 the Allies lost, a ship tonnage of about 7’000’000 tons, which means every month between 70 and 350 ships (April 1917) that correlates perfectly with the exceptional summer sea icing in the North Atlantic during the months April to July 1917.

During the remaining 10 full war months in 1918 the Allies lost another 2’500’000 tons. The total loss of the Allies ship tonnage during WWI is of about 12,000,000 tons, or about 5,200 vessels. Somewhat five million tons of cargo and store must have been on board of the sinking ships. The total loss of all naval vessels (battle ships, cruisers, destroyers, sub-marines, and other naval ships) amounted to 650, respectively 1,200,000 tons. How many ammunition, shells, torpedoes, and bombs were used in countless encounters is impossible to verify.

Not less than 200’000 sea mines were placed (Fig.17), of which about 75’000 had been used to build the Northern Barrage between Orkney Island and Norway during summer 1918 (Fig.18). Only few months later the temperatures at Spitsbergen went into a steep rise that became the EAW.

Brief overview of some sea and weather observation.
As the assumption of a comparability between a number of weather conditions during WWI and WWII is not yet a settled issue, and it is not possible to be discussed here, a few aspects shall nevertheless be mentioned in chronological order. This is merely done to indicated that a thorough analysis of the entire period could be of considerable help to understand the reasons of the EAW better.Â

__(A)  The Arctic temperature record north of 70°North indicate a period of slightly lower temperature between 1915 and 1918.(Fig. 2, 3, and 13). See also: Fig 22 (SST,  NW of Scotland; and Fig. 23 (SAT, Thorshaven/Faroe Is.).

__(B) The famous icy winter battle in Masuria (north-eastern Poland) in February 1915 between the German Army and the Russian Tenth Army, caused the German Field Marshall Hindenburg to question: “Have earthy beings really done this things or is all but a fable or a phantom”, (citation from: NYT, 07 January 1942)

__(C) The winter 1916/17 was one of the very cold winters in Northern Europe.

• The German attack on Verdun started on February 21st 1916 with one million troops; the battle became the longest of WWI and ended on December 18th 1916. French and German Army lost several hundred thousand men each. From a climatic perspective it is to note that close battle field regions had been wetter than usual, e.g. Baden had been 30% more precipitation, in the Black Forest rain was even 50-80% higher than normal.

Along all coastal areas of Great Britain the winter season 1916/17 (DJF) was the coldest for about two decades (e.g. Fig. 19) including Thorshaven/Faroe Island (Fig. 23), also along the eastern side of the North Sea up to Norway (Torungen Fry), while for example the record at Aberdeen/Scotland had a similar cold season only a few years earlier.

Fig.19; Air Temp.(DJF) 1900-1927 Scarborough/UK	Fig.20; Sea Surface Temperature in the English Channel, 1904-1927

• For Great Britain it had been the third coldest winter during the last century (together with war winter 1939/40). All three winter months were beneath 2.0C.³

• The sea surface temperatures in the English Channel had been the coldest between 1903 and 1927 (Fig.20).

• On Spitsbergen the months February, March, April, and May 1917 had been the coldest ever recorded.⁴

__(D) The Baltic Sea sea-ice conditions extended during the war each year until naval war activities ended with the Russian Revolution in October 1917. The sea-ice cover during the winter 1917/18 was immediately much less. (Fig.21)
Fig. 21

__(E) At least one report exist claiming that the sea water at the west coast of Spitsbergen had shown unusual high temperatures in summer 1918. (Weikmann, 1942)⁵

__(F) During the Spitsbergen winter of 1918/19 the temperatures varied considerably. There were long periods in November and December 1918 with temperatures close to zero degrees, 4 days with temperatures above zero in November and 7 days in December. In January 1919, the temperatures did not reach –5°C for 14 days, and five days were frost-free.⁶ __(F) The Fisheries Research Service/Aberdeen took sea surface temperatures in the Scotland – Faroe Channel that show a dramatic drop from about 1914 to 1920 (Fig. 22), whereby the timing is, based on the SAT from Thorshaven (Fig. 23), actually from 1914 to 1919 as the air temperatures level from 1914 is already reached again in 1920 (Fig.23).

Fig. 22; SST Scotland- Faroe Channel	Fig.23; Air Temp. Thorshaven /Faroe Is.

__(G) The Russian scientist Jules Schokalsky informed the Royal Scottish Geographical Society in  1935: “The branch of the North Atlantic Current which enters it by way of the edge of the continental shelf round Spitsbergen has evidently been increasing in volume, and has introduced a body of warm water so great, that the surface layer of cold water which was 200 metres thick in Nansen’s time (1895/96), has now been reduced to less than 100 metres in thickness.”⁷

This few mentioned situations should just give an idea that there might be many hundred other suspicious weather or sea observations, which meteorology should identify and analyse for a fully understanding of the WWI interconnection between naval war and weather conditions .

Causation III: Which evidence is possible, or sufficient to draw a link to naval warfare?

As the data required to present a 100% proof are missing to 99,999%, namely ocean data over considerable time periods, space, and depths in many millions, and because only few air temperature data are available, a full proof in out of question. Ideally we seek “empirical evidence”, that is the basic practice of science, which relies on direct experience or observation in order to describe or explain phenomena.  In a strict sense it requires that observations are being potentially replicable, a non option for the EAW case. On the other hand it was possible to list a number of observations and phenomena, which are closely linked by time, space, and exceptionality, to a strong force, namely naval warfare, and to one or more effects, e.g., unusual sea and air temperatures in 1917 & 1918, the North Atlantic sea ice in summer 1917 (Fig. 9-12, and 24), and the temperature jump at Spitsbergen during winter 1918/19 (Fig.25). That is not a proof of a causality, but the closer, stronger, and comprehensive the observation correlate with each other, it can reach a stage of a “prima facie evidence”. Prima facie denotes evidence which – unless rebutted – would be sufficient to prove a particular proposition or fact⁸.Fig. 24

Our case is strong in at least two aspects, which can not be rebutted with reference to “natural variability”, namely:

• The extensive sea icing in the North Atlantic in summer 1917, that happened only this time during the last 110 years, and

• The sudden Arctic winter warming 1918/19 (in the Atlantic section), which was presumably the highest temperatures rise in the Arctic ever recorded.

If these events shall be regarded as ‘natural’, the claimants of such assertion need to prove that this happens frequently, and that they are able to compare it with other observation of a same or similar nature. If they remain silent, they have to accept that the naval war thesis is a serious option and a necessity to investigate.

With regard to the summer sea ice 1917, it is very difficult to name a possible cause. One can exclude that the icing had been generated from atmospheric conditions, and if, than only marginally, as the sea off Spitsbergen was still ice free in March, which only ended in April at a time the sun has already influence⁹. Also any assumption that favourable conditions for icing could have come from the ocean interior seem a to remote possibility. Considering a link to naval warfare would require to come up with pollution, in a way that indicates to conditions that favour icing conditions, a matter completely out of reach for this paper. That is a task of universities and institutions, and is in the responsibility of governmental departments in charge of climate change matters.

Concerning the sudden temperature shift in winter 1918/19, my consideration starts with the observation by Jules Schokalsky, that between about 1895 and 1935 the body of warm water (West Spitsbergen Current) was so great, that the surface layer of cold water of 200 metres was reduced to less than 100 metres in thickness (see above). This observation leaves two options for the process that happened over the time span of 40 years:

• the decrease of thickness over 100 meter occurred gradually, e.g. about 2,5 meters per year, or

• it happened within a very short time span, with an initial push during a couple of months prior, and during winter 1918/19, causing a significant shift that lasted for two decades.

All circumstance leave little room for not taking the push option, but to assume a kick off situation.
Although the push-option could have started as early as in winter 1916/17, it seems only remotely possible that any major influence could have been coming from the low winter air temperatures between Europe and Spitsbergen. The starting point is more likely the summer sea ice in 1917 (Fig.24), by setting ocean internal process in motion, which is unfortunately completely out of reach for any consideration here. But there is at least the information that the SST at Spitsbergen in summer 1918 had been unusual high, and the extraordinary low SST in the Scotland – Faroe Channel (Fig. 22) in the second half of the 1910s, making it virtually impossible to assume ‘natural variability’ by a complete ignorance of the naval war. Fig. 25

In support of ‘prima facie’ it shall be once more repeated what has already been outlined in the previous paper, that there was nothing in “the air”, for example a volcanic eruption, or a major earth quake, or a tsunami, or a meteorite plunging on land or into the sea, which could have caused the sudden temperature shift in the high North. Instead there was a devastation war in Europe, and huge naval activities which penetrated deeply huge sea areas, of which the water masses all ended up after a short period of time where the shift commenced.

Conclusion
The Arctic warming from 1920-1940 is one of the most puzzling climatic anomalies of the 20th century, says Bengtsson, et al., 2004¹⁰. Meanwhile, the time available for science was more than 90 years, but they are not even able to reckon that the early Arctic warming (EAW) commenced within a very short period during which a number of strange meteorological observation could be made, e.g. in Europe (winter temperature), in the North Atlantic the summer sea ice in 1917, and the temperature shift at Spitsbergen in winter 1918/19, which is topped by a simultaneously operation of a disastrous naval warfare in a huge sea area around Great Britain. Due to the prevailing ocean current system, the assumed cause (naval warfare), and the observation in the northern North Atlantic and the adjacent Arctic Ocean sector, the human activities and the significant meteorological changes occurred, practical at one and the same location, in the northern North Atlantic and adjacent Arctic Ocean sector.
The circumstances are so numerous and closely interrelated, and the two major events in the North Atlantic are so exceptional, that it is time that atmospheric science solves the puzzle, or rebut the prima facie evidence that the naval war contributed. Regardless whether the role of naval war during WWI had been only marginal, medium, or considerable, for a science that talks about the danger of climate change it is irresponsible not to know precisely, the circumstances of the EAW, why it happen and why it stayed from winter 1918/19 to winter 1939/40, and whether man did contribute by a naval war in Europe.

Full text in PDF: HERE (1 MB)

1. Web page: t.a.harley;http://www.personal.dundee.ac.uk/~taharley/1917_weather.htm
2. A.J. Drummond (1943), “Cold winters at Kew Observatory, 1783-1942″; Quarterly Journal of Royal Met. Soc., No. 69, 1943, pp 17-32).
3. Web page: t.a.harley;http://www.personal.dundee.ac.uk/~taharley/1917_weather.htm
4. See: Spitsbergen data 1912 – 1926 at: Annex A ; and  Isfjord Radio data 1912-1976 at:GISS-NASA
5. Weickmann, L.; ‘Die Erwaermung der Arktis’, Berlin, 1942.
6. See: “Arctic Heats Up”, page 60, (Further Reading).
7. Schokalsky, J. (1936); ‘Recent Russian researches in the Arctic Sea and the in mountains of Central Asia’, in: The Scottish Geographical Magazine, Vol. 52, No.2, March 1936, p. 73-84.
8. See: http://en.wikipedia.org/wiki/Prima_facie
9. To rely in this situation on the very cold Spitsbergen temperature from February to May 1917 (the lowest ever recorded), could prove to be tricky, as much lower air temperatures can be assumed inevitable from the moment the usually sea ice free tongue of Spitsbergen was gone in April, which lasted until July 1917.
10. Bengtsson, Lennart (2004), Vladimir A. Semenov, Ola M. Johannessen, The Early Twentieth-Century Warming in the Arctic-A Possible Mechanism, Journal of Climate, October 2004, page 4045-4057.

Further Reading:
___Book (2009)__ “Arctic Heats Up. Spitsbergen 1919 to 1939″;http://www.arctic-heats-up.com
___Paper (2010)__“Indian Drought and North Atlantic 1917 & 1918″(PDF, 1MB)
___Paper (2009)__“The Circumstances of the Arctic Warming in the early 20th Century”(PDF, 0,9MB)
___Home Page___ http://www.arctic-warming.com/

Figures:
__Fig. 13; Redrawing of data from Nasa-Giss & junkscience image.
__Fig.14-17, Various sources, and from the material indicated in Further Reading.
__Fig. 18; The layout is based on information from: Daniels, Josephus; (1920); ‘The Northern Barrage’, No.2 (The Northern Barrage and other mining activities), No.4, The Northern Barrage – Taking up the mines), Publication, Navy Department,
Washington Government Printing Office, 1920.
__Fig. 19; Air temperatures Scarborough/UK data from Nasa-Giss.
__Fig. 20; Based on data from: Lumby, J.K..; (1941); ‘Seasonal changes of water temperatures with depth’; Quarterly Journal Royal Meteorological Society, Vol. 67, July 1941, p. 234-238.
__Fig.21; Drawing based on data from Finnish Marine Research 1988, at page 91 of the book “Arctic Heats Up”.
__Fig. 22; Data source: Fisheries Research Service/Aberdeen; And a redrawing of material at:http://ansatte.hials.no/hy/climate/defaultEng.htm, Harald Yndestad,Aalesund university college,
__Fig.23: Based on Nasa-Giss data
__Fig.24; Source as indicated, and at page 91 of the book “Arctic Heats Up”.
__Fig. 25; based on material by: Hesselberg, Th., Johannessen, T. Werner; (1958); in: R.C. Sutcliffe, ed.; ‘Polar Atmosphere Symposium – Part I, Meteorology Section; Symposium at Oslo 2-8 July 1956, London, pp. 18ff; Figure 2.

 

By Arnd Bernaerts, Here posted on 30th November 2010
Earlier posting (20Nov/10) diggingintheclay & (29Nov/10) The Air Vent
Avaible as a PDF

Introduction: Surprisingly, 90 years ago there was a pronounced warming all over the Northern Hemisphere for two decades, but it is still not clear when this warming started. A number of authors identify as period the 1920s and 1930s and the IPCC Report 2007 mention the time from 1925 to 1945¹ , and a recent posting at: Verity Jones Blog on „Mapping global warming“ by ‘KevinUK’ (January 18, 2010) marked 1910 as the beginning of the warming period, and analysing convincingly that: “much of the claimed global warming is hardly global at all. In fact it looks to be more accurately Northern Hemisphere warming, and for that matter primarily Northern Hemisphere WINTER warming!“ With interesting access to data and maps it is an enjoyable reading, confirming that since 1880 there had been four distinct warming/cooling time periods i.e. from 1880 to 1909 (cold), 1910 to 1939 (warm), 1940 to 1969 (cold) and 1970 to 2010 (warm). From the dates given, I would like to object the date 1909/10, which should not be considered as the change from a cold to a warm period, as this happened some years later towards the end of the decade 1910-1920, between 1916 to 1920, presumably in winter 1918/19. Figure 1 reflects the situation from 1921 to 1930 (Details to the figures in the annex). Does it matter to be very persistent in this respect? The answer is clearly yes. The more precisely a shift from a warm to cold period, and the region where it occurred is identified, the more it might be possible to identify the cause. For this reason the following discussion is about the start of the first pronounced warming period after the end of the Little Ice Age, which actually commenced as an Arctic warming, primarily close to the Fram Strait region.

Figure 2 (Spitsbergen 1910-1955)	Figure 3 (70-90°N, 1880-2010)	Figure 4 (70-90°N, 1880-2004)

Overview: A substantial point observed by ‘KevinUK’, as already mentioned, is the more pronounced warming of the Northern Hemisphere and primarily during the winter season. That is exactly what the warming period in the early 20th Century is primarily about. While the summer temperatures increased only modestly, the winters generated the steep warming as observed at Spitsbergen (Fig.2), which is also well reflected in the annual data set for north of latitude 70°N (Fig. 3 & 4). The decade from 1921 to 1930 showed a remarkable winter warming (Fig. 5 & 6), which lasted until 1940 (Fig. 3 & 4). This fact is a paramount aspect to identify the reason for this significant shift during the winter period as the influence of the sun is remote north of 50°N (i.e. London, Vancouver), but any warming must have been coming from somewhere.

Figure 5 (1921-1930)	Figure 6 (1920-1939)

Time and Region: The Figures 1, 5 & 6, give a clear indication that the previous warming period in the 1920s and 1930s was primarily located in the North Atlantic section of the Arctic Ocean. Figure 2, 3 & 4 demonstrate equally that the temperature rise commenced before 1920 (Fig. 5 & 6), probably in 1918 (Fig. 2). The later date (1918) should be regarded as the time the Arctic suddenly moved into a strong warming period. Actually, the warming started in the Spitsbergen region in winter 1918/19 (Fig 7, Spitsbergen D/J/F), and was only subsequently observed beyond this station. Under these circumstances it seems difficulty to regard the year 1910 as starting point. With some generalisation there had been a modest temperature increase before 1910 (Fig. 4), with a significant decrease from 1910 to 1917. At Spitsbergen the shift is between DJF-1912/18 and DJF-1919/23 is about 8°C, for the whole Arctic region the increase between the decades before and after 1919 (Fig.3 & 4) is about 2°C.

 

Figure 7	Figure 8

Causation I: West Spitsbergen Current: Having established the time and region of the sudden temperature shift close to Spitsbergen and narrowed it to the winter 1918/19, it is time to ask, what caused and sustained the warming for two decades. For example ‘Kevin/UK’ states on the analysis of his Figure 8 that: “This is demonstrates clear and significant natural climatic variability during this time period in different parts of the world”, and is reasoning in one comment that: “I’ve personally far happy to convinced that these observable difference in differential warming/cooling trend could be caused by differences in water vapour concentration/relative cloud cover, particularly late evening/night time cloud cover.” The cause is presumably another one.

The Arctic Ocean winter weather is dominated by a sunless period over more than 6 months, a full sea ice cover, extreme cold, low humidity, low cloudiness, and anticyclones. Neither sun spots, nor carbon dioxide, nor water vapor can be considered as a significant direct contributor to generate a sudden remarkable shift, and keep it sustained over two decades. As there is not any indication that the warming had been generated elsewhere, and subsequently been moved to the polar region (Fig. 1, 5 & 6), it must have been a local source, namely warm high saline Atlantic water, which is carried by the West Spitsbergen Current to the Arctic Ocean. Whether this change was due to an increase of the water masses, or due to a change in the structure over the various sea levels over a considerable depths around the gate to the Arctic Ocean, the Fram Strait, is not known. It seems that the latter is the more likely reason. (More details in Book-Chapter 7)

Causation II: Shift of sea level structure. Little is known about an extraordinary North Atlantic sea ice season in 1917. To my knowledge, such a long and extensive sea ice cover occurred only once through out the 20th Century. Usually there remains a sea ice free tongue off the shore of Spitsbergen (Fig. 9). Against all rules, the tongue disappeared in April 1917, the sea ice extended far to the South (Fig.10), remained very high throughout June (Fig.11), and only retreated in July 1917 (Fig. 12). About the consequences one can only speculate, but it was certainly not without any.

Figure 9	Figure 10	Figure 11	Figure 12

 

Throughout the long freezing process the ice-covered sea surface level must take the release salt, which makes the sea water heavy, and thus increases the vertical water exchange with deeper levels. During the subsequent melting process since July 1917 the sea surface receives a huge amount of fresh water, which stays at the surface level, until the salinity and/or water temperature is back to the normal. This highly unusual event in the Northern North Atlantic from April to July 1917 could well have contributed to a shift in the ocean structure between Spitsbergen and the Fram Strait, which subsequently caused the warming of the Northern Hemisphere from winter 1918/19 to 1940.

Causation III: The change in the northern NA ocean structure. This is worth to be discussed separately another time. For now only this brief comment: As there was nothing in “the air”, for example a volcanic eruption, or a major earth quake, or a tsunami, or a meteorite plunging on land or into the sea, it might be necessary to recall what happened in Europe from 1914 to November 1918. Over four years a devastating battle on land, in the air and at sea took place. Huge naval forces battled in the waters in the east and west of Great Britain, it is my view that this may have changed the sea structure with respect to heat and salinity over many meters depth. All water moved north with the Norwegian Current, and the West Spitsbergen Current, to enter the Arctic Ocean after a time period of several weeks or months (Fig. 8). That could have influenced the exceptional sea ice conditions during summer 1917, or even may have contributed alone, via a change in the ocean structure between Spitsbergen and Greenland, the climatic shift in the high north in winter 1918/19.  (More details in Book-Chapter 8)

1. For details see the link in Further Reading:  “Arctic Heats Up”, Chapter 2, p. 16f., (i.e. Drinkwater, 2006; Bengtsson, 2004, Johannessen, 2004) .

Further Reading:
____Book (2009)____“Arctic Heats Up. Spitsbergen 1919 to 1939″; http://www.arctic-heats-up.com
____Paper (2010)____“Indian Drought and North Atlantic 1917 & 1918″ (PDF, 1MB)
____Paper (2009)____“The Circumstances of the Arctic Warming in the early 20th Century” (PDF, 0,9MB)
____Home Page____http://www.arctic-warming.com/

Figures:
__Fig. 1; based on material by: R. Scherhag, (1936), “Die Zunahme der atmosphärischen Zirkulation in den letzten 25 Jahren.”, Annalen der Hydrographischen Meteorologie, Vol. 64, p. 397ff, Tafel 62, Figure 10.
__Fig. 2; based on material by: Hesselberg, Th.,  Johannessen, T. Werner; (1958); in: R.C. Sutcliffe, ed.; ‘Polar Atmosphere Symposium – Part I, Meteorology Section; Symposium at Oslo 2-8 July 1956, London, pp. 18ff; Figure 2.
__Fig. 3; download from:  http://www.climate4you.com/index.htm>>“Temperature in Polar regions: Arctic and Antarctic”, >> Arctic temperature change, showing the mean annual surface air temperature (MAAT) anomaly 70-90oN compared to the WMO normal period 1961-1990, as estimated by Hadley CRUT. HadCRUT3 temperature data from the Climatic Research Unit (CRU) has been used to prepare the diagram.
__Fig.4; Download from http://www.pi-news.net/wp/uploads/2008/10/arktis3.jpg
__Fig. 5; based on material by: R. Scherhag, (1936), see Fig. 1; Tafel 58, Fig. 2 (Temperature deviation from November to March 1921-1930 versus long term mean.
__Fig. 6; based on material by: Ola M. Johannessen, Lennart Bengtsson, Martin W. Miles, Svetlana I. Kuzmina, Vladimir A. Semenov, Genrikh V. Alekseev, Andrei P. Nagurnyi, Victor F. Zakharov, Leonid Bobylev, Lasse H. Pettersson, Klaus Hasselmann and Howard P. Cattle;  “Arctic climate change – Observed and modeled temperature and sea ice variability”;  Nansen Environmental and Remote Sensing Center, Report No. 218, Bergen 2002; Tellus 56A, (2004), p. 328 –341, Figure 2 (SAT trends north of 30°N in the winter period from  November to April, 1920-1939)
__Fig. 7; based on Giss data: Source: Paper (2010)__“Indian Drought and North Atlantic 1917 & 1918”
__Fig. 8; Source:Chapter C (here: amended)
__Fig. 9 – 12: based on data from:http://polar.ncep.noaa.gov/seaice/climatology/months.shtml; Source: Paper (2010)__“Indian Drought and North Atlantic 1917 & 1918”

Avaible as a PDF

 

The Arctic sea ice cover was the lowest in recent decades for six weeks during May and June 2010. Since it recovered above the level of the last three years. (see Fig. right from 22Aug.2010). The decline in 2007 received considerable attention, e.g. by the NYT on 2nd October, 2007: “Scientists are also unnerved by the summer’s implications for the future, and their ability to predict it”. They should blame themselves.

There had been a Artic warming period for two decades in the first half of the last Century. Start and end of the warming was already recognised by H. W. Ahlmann in 1946, a minor warming “increased rapidly during the last decades [1918-1940]” . Although science has had ample of time to understand this extraordinary period thoroughly, the results are still poor. Also their predecessors during the pre and post WWII years failed to recognise the most northern sea areas of the Atlantic, respectively the West Spitsbergen Current as the primary source (see the references on this site). Why shall be discussed along a paper from the late 1940s, I was reminded while visiting the very informative “climate4you.com” today, which had caught my interest due to its very comprehensive list of references (about 400) some years ago: “Recent climatic fluctuations” by Leo Lysgaard .

Lysgaard recognises, like Ahlmann, that the winter warming in the Arctic had been more  pronounced that during the summer season, but is much more unspecific (1949: Recent climatic fluctuations by Leo Lysgaard ). Thereon he discusses in Section 5 the “Cause and Effect of the Climate Variation”, and three possible ways of explaining the observed warming of the atmosphere:

1. It can, inter alia, have received more heat from the interior of the Earth.
2. It can have radiated less heat into space as a result of a change of the contents of carbon-dioxide, aqueous vapour, volcanic and electrical particles of the atmosphere.
3. It can have received more heat from the sun in consequence of a variation in solar radiation or the contents of volcanic and electric particles.

“climate4you” selected the following Lysgaard explanation:
____”As regards Point 1, the quantity of heat which the atmosphere receives from the interior of the earth is extremely insignificant and as far as is known, no measurements exists indicating that the rise in temperature and the increased atmospheric circulation of recent years should be due to the heat of the earth.”
____”As to the other points, no measurements exist either which indicate that the carbon-dioxide contents have so increased that they have importance for the hot-house effect of the atmosphere. The course of the curves seems also to show that the carbon-dioxide cannot have caused the climatic variation.”
____”We will, however, keep to the causes of the present climatic fluctuations and to indications that the cause is to be found in an increase of solar radiation. One must prognosticate here that an increase of solar activity does not necessarily cause a rise in temperature over the whole earth, in any case not immediately. It is so that a variation in one weather element will inevitably cause variations in all other elements, a state of affairs which makes the whole problem so intricate and beyond computation. A temporary fluctuation of the solar radiation can thus very well produce a climatic fluctuation of considerably longer duration on the earth.”

No wonder that he contributed little to the understanding of the Arctic warming many decades ago. Like many of his colleagues at that time the oceans did not exist. The important aspects that the temperatures in high latitude regions during the winter season depend heavily on heat supply from the sea, and that any fluctuation of solar radiation have a minimal, if any, effect during the polar nights, is completely ignored.  That he denies a detectable impact of carbon-dioxide on the climate variation should be of interest to those who make such claims today.

Left Fig: Annual Air Temperature  2009 vs mean 1998-2006 (see Reference)

Although Lysgaard’s considerations would presumably receive little support nowadays, modern Arctic science has hardly achieved more in understanding the reasons that lead to the Arctic Warming since winter 1919. That is even more surprising  when it is meanwhile called :  “as one of the most spectacular climate events of the twentieth century” (Lennart Bengtsson et al , 2004), due to: “temperature increase in the Arctic was related to enhanced wind-driven oceanic inflow into the Barents Sea with an associated sea ice retreat.” That is progress, but to little. On one hand the influence of the West Spitsbergen Current has not been investigated, on the other hand the significant difference between summer and winter temperature is to little addressed. But more importantly nothing has been said on what has caused the “enhanced wind”. The matter is about an enhance winter warming over two decades, which needs  a increased and permanent heat supply from the sea, which in this case from the West Spitsbergen Current.
By Arnd-Bernaerts/23 August 2010

Figure reference:
__Ice cover 22. August 2010:  Danish Meteorological Institute Arctic Sea Ice Extent
__Decadal Arctic temperature data source: NASA Goddard Institute for Space Studies(GISS), as at:  climate4you.com (Arctic precipitation and temperature change during the 20th century ).
__Annual temperature in 2009 vs average 1998-2006; source: NASA Goddard Institute for Space Studies(GISS), as at: climate4you.com. (Section: Arctic temperature change )

14–18 December, San Francisco, California, USA

 

Paper Number:GC51A-0738 , Poster Presentation

Poster in PDF

Presentation Date and Time: December 18, 2009; Location: Poster Hall, Moscone South

Arctic Warming Phenomena 90 Years Ago

ABSTRACT : Due to higher winter temperatures there had been a significant warming in the Arctic from 1919 to about 1940. Only a few details of locations, timing and possible sources of warming are available. Answers can be found if research is confined to an extreme temperature rise during the winter season. Within the Polar Circle, any winter warming is closely related to a number of prevailing circumstances, e.g., minimal direct influence by the sun, sea ice conditions, and the ocean current system.
Meteorological data from the Arctic Ocean region, Greenland, Iceland, North Europe, and Russia are analyzed in order to establish with accuracy, where and when the warming appeared, and its magnitude. Establishing the location and the precise timing is a paramount precondition to discuss the source of the event and its sustaining for two decades.
Thus the study can show that the extraordinary warming in the polar region since 1919 was not an Arctic but a Spitsbergen warming. The higher temperature rise could have only been generated in the sea ice free ocean off the western coast of Spitsbergen, where the warm and saline West Spitsbergen Current is entering the Arctic Basin. A detailed comparison of various coastal stations in the Northern North Atlantic from Russia to West-Greenland show that the rising trend started at Spitsbergen. At more southern stations in Northern Russia and Norway, as well as on Iceland and Greenland at no time there had been any significant surplus of heat, which could have had the ability to supply the winter warming at Spitsbergen for two decades.

AUTHOR: Arnd Bernaerts; KEYWORDS: [9315] GEOGRAPHIC LOCATION / Arctic region, [1616] GLOBAL CHANGE / Climate variability, [1635] GLOBAL CHANGE / Oceans, [0750] CRYOSPHERE / Sea ice.

American Geophysical Union, 2000 Florida Avenue N.W. Washington, DC 20009-1277 USA

The Circumstances of the Arctic Warming in the early 20th Century

For the second time a Online-Conference, “Climate 2009”, is operating from 2-6 November 2009; (HERE). Approximately 100 paper present the latest scientific findings on the social, economic and political aspects of climate change. The Conference sitehttp://www.klima2009.net/en/start invites to participate:

“Climate 2009 / Klima 2009″ will encourage more networking and information exchange among participants and hopefully catalyse new cooperation initiatives and possibly new joint projects. Besides the refereed scientific papers, we will offer you a chance to discuss the problems, barriers, challenges and chances and potentials related to climate and sustainability research. Special discussion fora and chat rooms will cater for direct interaction with the participant scientists.

Here are the first lines from one of the papers that discusses  Arctic matters – see section: Papers – Category 2 “Economic aspects of climate change” – (ca. 10 pages plus 22 graphs) :

The Circumstances of the Arctic Warming in the early 20th Century

Introduction

The Arctic is an ocean. By the Fram Strait at about 80° North, between Greenland and Spitsbergen, it is connected with the Atlantic, which serves as a major gate for the supply of warm and saline water to the Arctic Ocean, which is coming with the West Spitsbergen Current. The subject of the paper is whether the warming in the early 20th Century has been caused here.
The term “circumstances” implies the observation or influence of “existing conditions”. Here the use of the term shall mean the presentation of circumstances which rectify to draw certain conclusions concerning the period of Arctic warming in the early 20th Century on how it started and how it shaped up. The paper will cover both aspects, but with a clear priority for

Fig. 1; Arctic Ocean  current system	Fig. 2; Permanent sea ice cover in the early 20th Century	Fig. 3; North Atlantic  current system

the circumstances around the year 1919 when the warming started. The method of investigation will be explained in the second section of the paper, based on a general picture that will be presented first of all. The third section is about the “circumstances” which will analyze temperature records in the Northern North Atlantic realm that may provide clues concerning the location, the timing, and the likely source of the warming event, and thereon discuss the information.

 

 

Arctic warming now and then

Overview

Nowadays the polar region is often mentioned, because the Arctic is currently experiencing a rapid warming with a dramatic loss of Arctic sea ice, which could be due to a combination of a global warming signal and fortuitous phasing of intrinsic climate patterns (Overland, 2008:289). The rapid warming is likely to be anthropogenic (IPCC, 2007b:83, 86). According to Serreze et al.: “Rises in surface air temperature (SAT) in response to increasing concentrations of greenhouse gases are expected to be amplified in northern high latitudes, with warming most pronounced over the Arctic Ocean owing to the loss of sea ice“, (Serreze, 2004). A recent U.S. government report concluded that the “temperature change in the Arctic is happening at a greater rate than at other places in the Northern Hemisphere and that the ice cover in the Arctic began to diminish in the late 19th century and this shrinkage has accelerated during the last several decades (US Geological Survey, 2009:486, 6). But the recent warming is the second during the last 100 years. The last IPCC report refers to a warm period from 1925 to 1945 (IPCC, 2007a:7), while an earlier report mentions a warming around the years 1920-1940 (IPCC, 1990:215). More to the point is the finding by Polyakov et al. that concludes: the warming during the 1920s –1930s was very fast in spring, autumn and winter, but much weaker and slower in the summer, while the period between 1918 and 1922 displays exceptional rapid winter warming (Polyakov, 2003:2072). Nevertheless the authors assume: that the complicated nature of the Arctic temperature and pressure variations is making the understanding of possible causes of the variability, and evaluation of the anthropogenic warming effect most difficult” (Polyakov, 2003:2076).

Continue to read the full paper  at >>>http://www.klima2009.net/en/papers/2/5

The West Spitsbergen Current (WSC) is getting more attention, but only with regard to recent years. For modern science the Arctic warming 90 years ago is still a non issue, although one could learn so much from it. For example: Piechura et al.(2009)[1]discuss the influence of a warmer WSC on the sea ice conditions north of Svalbard with the main conclusion, that it is primarily the heat transport to the Arctic Ocean (AO) by ocean currents, the West Spitsbergen Current (WSC) in particular, that is playing a significant role in the process of Arctic warming. Actually their investigation focused on the short warming period from 2004-2006.

NOTE: The graphic “Svalbard Luft”  indicates a warming from 1980 until 2006, and decreasing annual temperature mean since 2007 

Other researcher concluded already earlier that “the Atlantic inflow is the primary source of heat to the Arctic Ocean (2007)[2], respectively that the fluxes from the North Atlantic through Fram Strait affect the heat budget in the Arctic Ocean (2003)[3]. Although Chylek et al.(2009)[4]acknowledge that the warming early last Century proceeded at a significantly faster rate than the current after app.1970, the previous warming is ignored.

This applies particularly to Chylek et al which suggest that the Atlantic Ocean thermohaline circulation is linked to the Arctic temperature variability on a multi-decadal time scale, based on the assumption that the Arctic had been warming from 1910 to 2008 interrupted by a significant cooling period from 1940 to 1970, and that the changes are highly correlated with the Atlantic Multi-decadal Oscillation (AMO). One can only wonder that they come up with a start of the warming in 1910 when the IPCC (2007:WGI) sets the date in the year 1925, and the IPCC-Report (1990, p. 228) mentions 1920, which is also confirmed by Polyakov et al.(2003).

NOTE: The graphic “Arctic-Winter” indicates the hot-spots in the 1920s, at Spitsbergen , +3,4°C, and West-Greenland, +3°C

A little historical research would have lead the researchers to the fact that the warming started in winter 1918/19 (HERE)[5]. By such a variety of dates more efforts may be needed to come up with convincing timing before talking about “multi-decadal” AMO. Even more questionable is the ignorance of previous IPCC conclusions. The first IPCC report  (1990:228) states that “Stronger westerlies over the Atlantic, do not, therefore, account for the Arctic warming of the 1920s and 1930s on their own: in fact they preceded it by 20 years”. If that is now regarded as wrong it needs to be said and explained.
More attention to the early Arctic warming that occurred 90 years ago, which had been subject to the last Hot Topic (26th June 2009), would have provided more insight in the functioning of the Arctic during the last decades, than one can learn from the papers mentioned.
___Svalbard Temp-Graphic; Source: NASA/Giss (download: Sept.2009).
___Arctic Winter Temp-Deviation, Source: Scherhag 1936.
ArndB/23 Sept.09

The International Arctic Research Center at the University of Alaska Fairbanks is a think-tank on Arctic matters primarily due to Syun-Ichi Akasofu (see recent Hot Topic) and Igor V. Polyakov.  In 2003 he and his colleagues emphasized that the period between 1918 and 1922 displayed an exceptional rapid winter warming in the Arctic[1]. Although this warming event had been as significant as the recent climatic change, little efforts has been made to learn from the past, instead the issue has been pushed aside by such remarks as e.g. “natural variability”(see: HERE).  Already 70 years ago the American scientist C.E.P. Brooks noted:  “In recent years attention is being directed more and more towards a problem which may possibly prove of great significance in human affairs, the rise of temperature in the northern hemisphere, and especially in the Arctic regions.”[2]

The sudden warming of the Arctic in the early 20th Century is presumably not as puzzling as assumed[3] if investigated on three parameters, namely winter temperature observation in the region, the prevailing sea ice conditions, and the impact the sea has on air temperatures at high latitudes during the sunless winter season. Who else than the ocean can influence the air temperatures at high latitude in winter. That is particular significant if the ocean space is free of sea ice and is supplied with warm water from elsewhere. In the Northern Hemisphere there is only one location where it happen, the West Spitsbergen Current, which supplies warm and saline water via the Fram Strait to the Arctic Ocean. (Discussed: Here)

Winter temperature deviation 1921-30, with 3°+ only at Spitsbergen and West Greenland
Extract from original R. Scherhag Fig., 1936	Winter deviation, 1933-35	Full year deviation – Nov.1936 to Oct. 1938

The starting point is the extreme warming at Spitsbergen in winter 1918/19. The winter temperatures exploded (see Fig. above) only here. The warming was sustained and remained for two decades, showing up in the Kara Sea and eastwards only after 1920. That is an evident aspect that the warming started at Spitsbergen.  When Syun-Ichi Akasofu[4] recently acknowledged  that: “The recent rapid retreat of sea ice in the Arctic Ocean, particularly in 2007, is partly caused by the inflow of warm North Atlantic (Karcher et al., 2003; Polyakov, 2006)“, it would be the same situation as during the Arctic warming 90 years ago. An earlier paper by Polyakov et al.[5] expressed it in this way:
„This study was motivated by a strong warming signal seen in mooring-based and oceanographic survey data collected in 2004 in the Eurasian Basin of the Arctic Ocean. The source of this and earlier Arctic Ocean changes lies in interactions between polar and sub-polar basins. Evidence suggests such changes are abrupt, or pulse-like, taking the form of propagating anomalies that can be traced to higher-latitudes. For example, an anomaly found in 2004 in the eastern Eurasian Basin took 1.5 years to propagate from the Norwegian Sea to the Fram Strait region, and additional 4.5–5 years to reach the Laptev Sea slope.“
Indeed, at first there is the Spitsbergen Current, and some time later, since the mid 1920s the region eastward from Spitsbergen generated a warming impulse on its own during the winter season (see Fig.-Box).  A thorough historical research of the early warming from app. 1919- 1939 would presumably have lead to a similar conclusion since long.
A detailed assessment on the early Arctic warming is  HERE

The author Akasofu explains his themes clear and comprehensively in the 54 pages long paper¹ . Concerning the early Arctic warming, which is subject of this website, the abstract says:

 

Subsequently the author explains (p. 44):

• It is important to note that the temperature rise from 1910 to 1940 was as steep as the one that started in 1975; the range of change was also similar. Although the IPCC was interested only in the rise after 1975, they should have also paid serious attention to the temperature rise between 1910 and 1940 and should have tried to understand its cause before deciding that the rise after 1975 was mostly due to the effect of CO2.

The author concludes that it is not appropriate to conclude -a priori- that the 0,6^oC rise is mostly due to human causes without carefully subtracting the contribution of natural changes.

However the overriding effort should be a detailed understanding of the warming in the early 20th Century, and we fully agree with Prof. Akasufo statement: “Thus, it may be concluded that processes other than the CO2 effect have a greater influence on sea ice in the Arctic Ocean than the greenhouse effects of CO2. The Arctic Ocean is special in this respect.“(p.40)

---

¹Online version 03/19/2009; S.I. Akasufo; “Two Natural Components of the Recent Climate Change: (1) The Recovery from the Little Ice Age (A Possible Cause of Global Warming) and (2) The Multi-decadal Oscillation (The Recent Halting of the Warming)”, at:http://people.iarc.uaf.edu/~sakasofu/little_ice_age.php 
²See the Homepage logo at: http://www.iarc.uaf.edu/