. The Eastern Bering Sea Shelf : oceanography and resources / edited by Donald W. Hood and John A. Calder . Figure 12-22. A schematic diagram of the band of ice in which the targeted ice floes were found after 23 hours. The location of the floes is marked using the same notation as in Fig. 12-18. The dotted portion represents the edges of the band characterized by small fragments of ice, pancakes, and larger, mostly submerged floes. Thus, for wind speeds less than 5 m/sec, like those during the first few hours of the experiment, the thicker ice might move 1-2 cm/sec faster than the thinner ice
. The Eastern Bering Sea Shelf : oceanography and resources / edited by Donald W. Hood and John A. Calder . Figure 12-22. A schematic diagram of the band of ice in which the targeted ice floes were found after 23 hours. The location of the floes is marked using the same notation as in Fig. 12-18. The dotted portion represents the edges of the band characterized by small fragments of ice, pancakes, and larger, mostly submerged floes. Thus, for wind speeds less than 5 m/sec, like those during the first few hours of the experiment, the thicker ice might move 1-2 cm/sec faster than the thinner ice. At wind speeds greater than 10 m/sec, this value may increase to a 10-20 cm/sec difference in speeds. These numbers confirm what we observed: before the experiment the winds were low and easterly, so that due to the Coriolis force the ice motion would have been to the northwest. In ad- dition, momentum transferred from the swell to the ice by reflection and absorption would have helped to form the compact ice edge which we observed at the start of the experiment. Then during the first four hours the winds, as Table 12-1 shows, came from the north as described above, and the targeted floes moved slightly south of the main edge. A speed difference of 1 cm/sec over four hours would cause the faster-moving ice to move about 150 m ahead of the slower ice. During the next five hours, the winds remained northerly and increased in speed, thereby increasing the difference in speeds and the distance between types of ice. In the final fourteen hours, the winds remained near 10 m/sec and the targeted floes were found some 15 km south of the ice edge. This requires an average difference in speeds of about 25 cm/sec. This number appears to be quite high when only wind and water stresses are considered; we must also consider the transference of energy and momen- tum from waves to the ice. Once the bands move away from the immediate ice edge, the absorption and reflection of wind waves also
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