Dmitrenko et al.: Oceanographic Causes for Trallsarctic Ice Transport
e
u
011
U
....
:c ,
drift ice
fast ice edge
fast ice
- isopycnals and isohalines
83
Figure 7: A scheme of the influence of the heat fluxes from the intermediate layer to the surface on the formation
of ice conditions in the zone of river water spreading. 1 - molecular heat exchange, 2 - convective heat exchange
at ice formation, 3 - double-diffusion convective heat exchange, 4 - heat exchange governed by isopycnic
advection of intrusions to the surface, 5+3 - heat exchange governed by the double-diffusion convection at the
upper periphery of isopycnic intrusions. The upper diagrams present the efficiency of each of the enumerated
processes calculated to centimeters of ungrown ice.
Table 1: Estimates of the Richardson gradient number for different shear values for the horizontal component of
current speed (Transdrift III, transect II data).
Station (KD95 .. )
48
49
50
51
52
53
55
54
DS
7.2
7.7
13.3
11.8
12.9
13.7
14.2
13.2
DU=2 cm/s
619
409
1121
1022
1194
2230
1858
5804
DU=15 crnls
11
7
20
18
20
40
103
33
III) across the zone of river water spreading (Figure 2B), These estimates were based on the
data collected by oceanographic stations during the onset of intensive ice formation and were