Scope and Aim
B. Cooling of Europe
Arctic Europe - winter of
C. Three European winters: 1939 – 42
153 Occupation of Norway - Return of Ice
D. Global sea war and climate changes
211 Oceans in times of war: 1942 to
E. Severe Warming 1918
251 Europe Weather-Influence by WWI (5_11)
F. Climate changes twice
303 Two wars at sea - Two climate shifts (6_11)
West Wind lost –
09 December 1939
09 December 1939
12 December 1939
Further details: (A) North Sea cooling, 2_16, and Baltic Sea cooling, 2_17.
*) German meteorologists prior WWII used the term ‘west wind drift’, a term which is today commonly used for Antarctic circumpolar wind and current.
II: The flow of ‘normal’ weather processes in the atmosphere
depends on the balance between humidity in the air and its concentration
and transport by low-pressure systems, or vice versa, the dry air of
high-pressure systems. This balance can be easily affected by reducing the
amount and concentration of ‘water’ in the atmosphere. That this
definitely occurred along and behind the Western Front of several hundreds
km length from Dunkerque (France) and
Further details: (A) Rain-Making, 2_31; USA dried out, 2_32, and War in China, 2_33.
chapter proposes to show that the meteorological developments since
September 1939 indicate clearly that conditions of the North Sea helped
pave the way for plunging North-Western Europe, from
According an analysis by the Neue Zürcher Zeitung (NZZ, 14 January 1940) the development of cold conditions happened as follows:
cold which flooded the whole of
convincing is the assumption made shortly after WWII, that the “shift”
to the severe winter conditions of 1939/40 was caused by a sudden build-up
of a cyclone off the Lofoten on 20th December 1939.
the scientific approach of this work is to elaborate historical data and
views, an exception shall be made with regard to recently published
articles concerning the long-distant effect of El Niño.
graphic – not enlargeable
Recently Stefan Broennimann and his colleagues inquired the causation of the extreme European winters 1940-42. We fully support the conclusion “that the global climate anomaly in 1940 to 1942 constitutes a key period for understanding of large scale climate variability”, but have reservations in following Broennimann et. al. linking the arctic war winters decisively to El Niño. As this is not the place to reply in detail, only a brief comment shall be given.
is a long established fact that El Niño events can be linked to unusual
short-term weather deviations in distant regions, but
in 3 to 7 years interval, a warm water pool that causes the
El Niño effect generates in the western Pacific
the full Chapter F from the new book 2012 (p.155-160) HERE
Any role of El Niño?
After all, the warm water pool is relatively small, presumably of a volume corresponding to a few times of water masses held by the North Sea when traversing the Pacific starts, respectively an area comparable to that of Australia, to a depth of 50 to 100 metres at a later stage. The extra heat stored is substantial but limited. The temperature may be up to 4°C higher than usual. Correspondingly the time duration for causing local and long distant effects is limited. The 1939 El Niño culminated in late summer 1939. Thereon El Niño receded, as the full cycle is 1 to 2 years. Even if the water pool still held any surplus heat it had little if anything to do with the record
Further details: (A) USA dried out, 2_32.
are even less reasons to assume that the equatorial Pacific had anything
to do with the 2nd and 3rd glacial war winter in
weather analysis by the NZZ on 14th January 1940 came to the
conclusion that the origin of the cold wave across
discussing the cooling of Europe in late 1939, a brief assessment of the
general conditions during the year 1939 will be presented in the form of
weather analysis clippings by meteorological services in respect of
following four extracts should be read keeping in mind that WWII started
in September 1939 and that climatic conditions were not necessarily
‘normal’ during the final four months of the year or first four months
of the war, i.e. September to December 1939. Particularly the record rain
area stretching from
Further details: (A) Rain-Making, 2_31.
weather conditions were almost average, the spring again had a succession
of warm spells interspersed with brief cold spells. After a warm and sunny
start in early June, the summer was comparatively sunshine-free with an
early autumn, with the exception of a warm period in August and early
September. As in previous years, November was very warm. There were,
however, very few gales. There was a notable above average rainfall in the
South-eastern districts and below average in the North-western districts.
Rains, far in excess, occurred in the Southeast. Actually, in October 1939
meteorological analysis for the months January - June 1939 notes a weather
with a tendency to be mild and partly too wet but mentions nothing special.
During the months of July and August 1939, the weather in
The start of the year 1939 was marked with mild winter weather with low wind cyclones and excessive rain. Spring months witnessed changing pressures with partly dry spells. The summer months were dominated by a low-pressure moving northeast, which brought along high precipitation to the Southwest of Sweden, in particular. Warm and dry summer weather appeared in August, when a high pressure dominated, which lasted through September. Then the weather became wetter and wetter with storms, which are usually rare during the season, becoming more frequent.
October, however, was characterized by several highs consequently making the weather relatively cold and dry. During the remaining months of the year there was a rather large number of lows, carrying along precipitation as well as storms. The last week of the year was marked by some lows – moving southeast – and brought along an exceptionally strong cold for the whole country.
1939 was a very rainy year. In Zürich it was the year with the highest precipitation for the last thirty years. The sunshine was one third less than expected. For the last fifty years no other year had witnessed less sunshine as 1939. Only January and April had normal sunshine; farthest away from normal were May and October, which reached a degree of cloudiness like never before. Compared with these extremes the average annual temperature was quite normal. As to the 75 year average, the average of 8.8°C of 1939 even showed a slight increase in the level of warmth by about one tenth of a degree. Still, 1939 was the coldest among the past six years.
Source: Neue Zürcher Zeitung; Montag, 8 Januar 1940
should be noted that the high precipitation is due to the heavy rain since
the war started. The triangle
details: (A) Rain-Making, 2_31.
weather conditions in
to the Neue Zürcher Zeitung (14 January 1940) the meteorological
conditions for the early cold in January 1940 could be traced back to the
first week of December 1939. (A) Indeed, on the 8th of December
the situation was conducive for an early winter and presumably cold start
into the winter season, when a solid high-pressure bridge stretched from
Scandinavia to France (see map above). Such a situation cuts Middle Europe
off from the weather making process in the
Further details: (A) above page 25.
It took only two weeks for
the first few days of September 1939 the weather in Western Europe was
influenced by a high pressure over
Book image – not enlargeable
It could well be possible that the cyclone’s movement was determined by
military activities in the Helgoland Bight and the laying of large mine
fields in the Middle of the North Sea (called: ‘Westwall’).
details: (A) Sea mines, 2_14.
the next two weeks the daily weather charts show quite solid proof of the
existence of a high-pressure area between
September 1939; Cyclonic activities over the
23 September 1939; With the advance of Atlantic air into Middle Europe a more forceful cyclone can develop along this channel (Rinne) which could extend its influence in the Middle Europe later.
The last two extracts show the high expectation that cyclonic activities
in Middle Europe will resume soon, which did not occur as indicated in the
following extract one week later.
1939; Along with a peripheral low, the first effective gust of maritime
air has reached
October 1939; A broad high-pressure bridge has formed between the Atlantic
1939; Usual weather is changing now and the high pressure bridge which
October 1939; Since a high pressure bridge from Middle Scandinavia to
End of October 1939; Analysis of the weather chart for November 2reads as follows:
Data for the next four weeks are mixed. Four statements made during the month may illustrate the situation as seen by the analysts who thought them worth mentioning at that time.
November 1939: It appears that now – like in many earlier years – a
WWD with lively cyclone activities will begin to move over
1939; It seems that a mainly sectional circulation is going to take over
in the general weather situation: its pressure field will be characterized
by a long high pressure zone – Azores –Southern Germany –
29 November 1939; West Siberian high is slowly retreating towards the East thereby allowing the disturbance coming from the West to penetrate still deeper into the regions of European Russia.
30 November 1939; A very distinct west wind weather situation rules over North and Middle Europe.
In summary the expectations of the weather analyst for ‘lively cyclone activities’ did not materialize. Seawater changes by devastating war machinery were not imaginable by weathermen then.
The first few days of December see attempts by rather weak cyclonic storms
to reclaim their common path of travel from the
21 December 1939 (not enlargable)
21 December 1939
25 December 1939
1 December 1939; Quite distinct Atlantic frontal zone of the last few days is disintegrating.
8 December 1939; It appears that the influx of warm air from the West is stronger than the retreating stream of cold air so that the high pressure bridge might stay, although the English frontal zone is currently progressing towards the East ever so slowly.
19 December 1939; A high-pressure ridge stretches….(etc). These conditions, however, are not likely to exist. The same pressure ridge is attacked from two sides and has gained more than 10mb in the past 24 hours….
21 December 1939; A high pressure area that yesterday lay over the
Northern coast of
Since this date the West Wind Drift was defiantly barred from
The foregoing investigation stressed the significance of the
observed change of wind direction in
At this stage it might be worth noting the research made by Drummond for Kew Observatory (London) in the early 1940s, that of the prevailing wind directions in South-West England during 155 winters from1788 to 1942 only 21 had easterly resultants whereby the few winters 1814, 1841, and 1940 had resultants from NE to ENE, meaning northerly than East. Another little number of winters since 1841 (1845,1870,1879, 1891, 1895, 1904, 1929) had prevailing SSE to ESE. With the exception of the winters 1801 and 1804 all of these 21 winters with predominant easterly winds had a temperature below average (40,1°F; 4,5°C). While eleven of the above winters had means between 34°F and 36°F, only few westerly resultants had means lower than 37°F, these being 1820,1830,1847,1855 and 1886.
In summary it can be established, that winter 1940 clearly played in the league of the Little Ice Age, being the only winter with wind from the NE quadrant since the end of the Cold Medieval Age Period. That had little to do with distant El Niño but a lot with the just started war at sea.
1939, on the question whether the usual west wind situation was returning
to normal, the analysts concerned may have become frustrated over the
delay. On 19th December it was regarded certain that the ridge
would cease, but the belief was in vain. The two low pressures may have
looked strong enough to fulfil the task, but what the analysts did not
know was that the regional seas were not able to act in unison. Only two
days later Central Europe was solidly under the control of a high pressure
bringing in air from Greenland or Russia’s North. The North and Baltic
Sea had lost too much of their heat capability to steer
Further details: (A) Winter 1939/40, 2_11; (B) North Sea cooling, 2_16, and Baltic Sea cooling, 2_17.