Preface The expedition ARK XIX/3 with the German icebreaking RV ...

due to shallow evaporation fog. Temperatures dropped to minus 3 ° C, which at that time
was the lowest record on the northern hemisphere.
During the first days of August the steering low pressure system for secondary
depressions between Iceland and the Kara Sea was situated in the vicinity of the pole.
From there a Swedish ship sent regularly weather observations. From August 2nd to 3rd
a couple of secondary lows moved from Jan Mayen to the northern Barents Sea. Thus
the wind veered northerly and under few clouds the visibility became very good.
Spitsbergen could be seen at a distance of about 130 km, at times associated with
mirages. In the evening of August 4th the research activity ended and “Polarstern”
headed towards Tromsø. During the transit winds came from south, later southwest to
west for a time about Bft 5. The distribution of wind and visibility is shown in the following
figures (Figs. A2.3.1-3).
35
30
35
Frequency [%]
25
20
15
10
30
25
20
15
10
5
0
N NE E SE S SW W NW
5
0
0 1 2 3 4 5 6 7 8
Wind Force [Bft]
Fig. A2.3-1: Distribution of wind direction during
ARK XIX/3c
Fig. A2.3-2: Distribution of wind force during
ARK XIX/3c
60
50
Frequency [%]
40
30
20
10
0
< 1 > < 2 > < 4 > < 8 > < 10 >
Visibility [km]
Fig. A2.3-3: Distribution of visibility during ARK XIX/3c
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