The Southern North Sea was immediately a
very highly frequented section by naval forces and activities during the
first few months of World War II, which increase the release the summer heat
quickly, by such events for example
(see Chapter 2_14):
- 3-9 September 1939: Four U-boats drop
magnetic mines in the estuaries of Orfordness, Flamborough, Hartlepool
and the Downs drowning four vessels with a total of 16,000-tons and
damaging one ship of 11,000-tons.
- 25 September – 23 October 1939: U-boat sea
mines barrage with 3,636 mines is laid across the Strait of Dover
(between Folkestone and Cap Gris Nez). After three U-boats were lost in October
1939, no further attempts were made by U-boats to reach the English
Channel through the Strait of Dover.
It followed a very cold winter. But
before that there was the intensive rain, an indication for a higher
evaporation at sea due to naval war (see Chapter 2_31),
- Southeast England recorded rainfall of more
than three times above average
Greenwich saw a higher rainfall only in 1888, and before that in
1840. Greenwich total for
October (6.16 in.) and November (4.13 in.) together –10.29 inches – was
the highest ever since recordinghad
begun at Greenwich. Similar conditions had been observed at Camden
Square (London), where hours of rainfall are recorded as follows: October 77.3 h.,
November 96.7 h. These were 50 hours higher than the average.
Until the end
of the year the sea off the coast of South England looses about 8-9°C of the
heat stored. Only a few degrees a couple of weeks earlier can make a big
difference to other winters.