23 
Fig. 9 shows progressive vector diagrams calculated from ADCP (A) and BSHcmod data 
(B). Generally, there is a considerable agreement both in current speed and direction. 
However, ADCP data show a northward flow at the end of the records, while model data 
exhibit a southward flow at 20 and 27 m depth. 
Table 5 compares basic current statistics. The ADCP sampling interval is 10 minutes, 
model data are available every 15 minutes. There is a good agreement of magnitude V s 
as well as of mean vector speed V v 2) . Differences within the near-surface layer are 
probably caused by the different depth levels (see Table 4, 0 m). Both data sets exhibit 
only small vertical shear, but there is a greater shear in the ADCP data for depths greater 
than 20 m. Good agreement between both data sets is also found for mean kinetic 
energy ku and eddy kinetic energy /ce 3) . 
Table 5: Current statistics Borkum-Riffgrund, BSHcmod (M) and ADCP data (A) 
sd 
m 
u 
cm/ s 
V 
cm/ s 
v s 
cm/s 
V v 
cm/ s 
dir 
O 
Jce k-n 
(cm/s) 2 
u'u' 
v'v' 
(cm/s) 2 
u'V 
k E /k H 
M 
0.0 
13.2 
8.3 
40.5 
15.6 
58 
922.0 
121.9 
1790 
54 
17 
7.6 
A 
5.3 
12.7 
11.4 
36.0 
17.1 
48 
657.2 
145.5 
1199 
116 
-177 
4.5 
M 
10.0 
10.1 
4.8 
38.4 
11.1 
65 
865.2 
61.9 
1674 
56 
52 
14,0 
A 
11.3 
8.5 
8.4 
37.4 
11.9 
45 
778.6 
71.0 
1482 
75 
-189 
11.0 
M 
to 
o 
o 
6.3 
1.7 
34.1 
6.5 
75 
681.3 
21.4 
1293 
70 
62 
31.8 
A 
21.3 
5.2 
3.0 
33.0 
6.0 
60 
631.5 
18.1 
1182 
81 
-108 
34.9 
M 
27.0 
5.1 
1.0 
29.9 
5.2 
79 
522.4 
13.7 
986 
59 
64 
38.2 
A 
27.3 
4.5 
0.4 
28.2 
4.5 
85 
453.6 
10.1 
819 
89 
-46 
44.9 
sd = sampling depth, dir = current direction