. The Eastern Bering Sea Shelf : oceanography and resources / edited by Donald W. Hood and John A. Calder . SEAWATER DEAD ZONE Figure 14-12. Composite figure showing the wave decay and induced circulation within the grease ice. The top shows a side-view photograph of grease ice in our tank; the bottom is a slcetch of the induced mean velocity and the final distribution of oil spilled in the ice. > grease ice, then slowly pumped onto the ice beyond the dead zone. Also visible in the photographs at 60 and 190 seconds are the small oil droplets which were produced by the turbulence at the lead
. The Eastern Bering Sea Shelf : oceanography and resources / edited by Donald W. Hood and John A. Calder . SEAWATER DEAD ZONE Figure 14-12. Composite figure showing the wave decay and induced circulation within the grease ice. The top shows a side-view photograph of grease ice in our tank; the bottom is a slcetch of the induced mean velocity and the final distribution of oil spilled in the ice. > grease ice, then slowly pumped onto the ice beyond the dead zone. Also visible in the photographs at 60 and 190 seconds are the small oil droplets which were produced by the turbulence at the leading edge of the grease ice and are being carried around within the grease ice by the circulation shown in Fig. 14-12. The last two photographs, at 240 and 310 seconds, show that most of the oil is now on the surface beyond the dead zone, with 5-10 percent of the oU circulating as droplets within the grease ice. For another view of the same experiment. Fig. 14- 14 shows several photographs taken with the hand- held camera. Fig. 14-14a shows the oil being poured into the tank, 14-14b shows the appearance of the oil at approximately 10 seconds, and 14-14c the appear- ance at 250 seconds. In 14-14c, both the wave decay and the pile-up of the oil at the dead zone are clearly visible. Figs. 14-14d and 14-14e, close-ups of the oil droplets, show that these droplets are approximate spheres of 1-3 mm diameter, and circulate within the grease ice without wetting it. Finally, Fig. 14-14f shows the appearance of the oil on the surface after the paddle was turned off at about 30 minutes after the start. In a result similar to Metge's (1978) obser- vations, the photograph shows that because of the grease ice, the oU moves less freely on the surface than it would on open water. To summarize, the laboratory experiments show that most of the oil ends up on the ice surface be- yond the dead zone, with some oil droplets circula- ting in the grease ice ahead of the dead zone. Our field observation
Size: 3046px × 1641px
Photo credit: © The Bookworm Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., book, bookcentury1900, bookcollectionamericana, bookleafnumber255
