Vertical Circulation Off the Ross Ice Shelf

• Main Author: C. W. Thomas
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 1965
• Subjects: Adare; Cape Adare; Edisto; Kainan Bay; McMurdo Sound; Queen Maud Land; Ross Ice Shelf; Ross Island; Ross Sea; Sullivan; Ice Shelf
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.504.5320; http://scholarspace.manoa.hawaii.edu/bitstream/handle/10125/7756/vol20n2-239-245.pdf;jsessionid=25FD059843F6196CD1E03054D89EA376?sequence=1

ABSTRACT: The Ross Ice Shelf is a floating ice mass about 200m thick over an average depth along the barrier of 567 m. In January the prevailing wind blows. from the east, parallel to the coast. The wind current transports the low saliniry layer (ca. 50 m) toward the ice shelf, where it must descend. Directly off the bar-rier we find low salinities to a depth of 150 m. The circulation here is quite similar to that defined by Sverdrup along the shelf ice of Queen Maud Land. Because of sinking of the low saliniry layer near the barrier, diatoms live in abun-dance at subcompensation depths, Trigonium arcticum actually on the sea bed. THE SOUTHERN BOUNDARY of the Ross Sea is fringed by floating ice of the Ross Ice Shelf ex-cept for the relatively small McMurdo Sound-Ross Island area. The clifflike barrier of the ice shelf is about 200 m thick (Sullivan, 1957). An average of 35 m rises from the surface of the water and about 165 m are submerged. The average depth along the barrier is 567 ill. The width of the shelf in places exceeds 1300 km. Since water can circulate beneath this huge ice mass we can expect unique features of circulation. The Ross barrier is washed by the Circum-polar Countercurrent which is produced partly by the distribution of density and partly by the prevailing wind. This current is usually weak along the barrier, but as it sweeps around Cape Adare it often attains a velociry of about 3 knots (author's observation). The data shown in Table 2 for station G-l indicate that at this station a weak current is flowing toward the east. This supports the postulation of Kort (1962), who projected such a current through the vicinity of this station. In all, three stations were taken off Kainan Bay (Ross Ice Shelf) along a north-south line at distances of 0, 40, and 156 km (Fig. 1). Two of these were taken in EDISTO and one in GLACIER. The work was carried out under the