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Circulation of the Atlantic water layer in the Canada Basin of the Arctic Ocean is re-examined using the numerous data acquired in the last decade. Methods of analysis were (1) the core layer method as used ten years previously, (2) a 500/1000-decibar dynamic topography, and (3) the available direct current measurements. The results confirm the general anti-cyclonic circulation deduced previously which has a transport of about 0.6 sverdrups. A new feature is described: a sub-surface counterflow moving southeast along the eastern slope of the Chukchi Rise with a transport of about 0.3 sverdrups.

Observations of finestructure formed in the mid-shelf front of a broad continental shelf sea provide unique data for elucidating the formation and subsequent behavior of distinct water parcels created by partial mixing of shelf bottom water and basin water. The measurements include one week of hourly vertical current profiles and grids of CTD stations. The partial mixtures are identified by a cold temperature signal from the shelf bottom water. They are extruded seaward from the mixing zone by pressure gradients along isopycnals into the graded density structure of water columns to seaward. If the mixtures have sufficient initial volume, they collapse into “blini” (Russian pancakes) of order 10 to 20 m thickness and 3 to 5 km diameter, the horizontal scale determined by the Rossby radius, and maintain a distinct dynamical identity after leaving the frontal zone. Salt-finger activity is associated with some of the initial mixtures but appears to be a transient phenomenon. If the ocean environment to seaward has low energy (as on the Bering shelf) the larger “blini” can have lifetimes of approximately one month.

Reports results of re-appraisal and interpretation of data from 74 oceanographic stations (of >400 occupied), listed according to vessel and source. Surface water occupies the uppermost 200 m It is almost continuously supplied by continental runoff from Siberia which mixes with and collects saline water, to a few hundred times its original volume, as it crosses the arctic shelf seas. The surface water then flows directly to the exit from the basin between Spitsbergen and Greenland. Three layers of surface water are distinguished, on the basis of temperature and salinity features. Variations and ranges within each layer are thought the result of geographic location, presence of ice cover, seasonal changes, convection , and advection. Lowest layer, from 100 m down to the Atlantic water, shows evidence of mixing with the subsurface layer, as well as evidence of continuous replenishment. Prevalence of the cold subsurface layer in this basin is explained by a proposed model, which recognizes the submarine canyons, notably the Svyataya Anna in the Kara Sea, as important factors in mixing and cooling and as primary sources of subsurface water.

Reports and discusses current measurements made Aug 1966 from USS Burton Island (AGB-1) in the strait which separates Vrangelya Island from the Siberian mainland. A significant tidal oscillation of the currents is caused by the semidiurnal tide wave of the Arctic Ocean, propagating eastward through the strait. The oscillation varies in amplitude with the semimonthly tidal inequality. The long-term mean flow through the channel appears to be controlled by continuity requirements of the Chukchi Sea - East Siberian Sea systems as it responds to the regional winds. When regional atmospheric pressure gradients dictate winds E of Vrangelya and/or northerly-southerly winds to the west, the flow is west-bound through the strait, and vice versa. The surface layer and ice field respond more directly to local winds.

Deals primarily with data from cruises of the Edisto, summers 1964-65, and 1965 drift of Arlis II; supported by the Office of Naval Research through the Arctic Institute of North America. Pt 1 summarizes previously published papers on the East Greenland Current, notes some bathymetric features of the western Greenland Sea and its water masses, and discusses general features of the velocity field, mean velocities and volume transports of the current.

The support of drifting stations and other scientific work on the pack ice by the Naval Arctic Research Laboratory is basic for the US studies of the central Arctic Ocean. A synoptic picture of temperature/salinity variables is needed, as is information on spatial variations of the currents. During the summer 1967, the satellite navigation system gave fixes of Fletcher's Ice Island T-3, from which water motion at depths of 150, 500 and 1300 m was recorded. Results of analyses are graphically shown and discussed; the technique used to smooth the track, noted. The flow is similar in the three water masses; a long-term period variation in the record probably represents the T-3 motion; there is a marked oscillation of ~semidiurnal period which undoubtedly represents an inertial or semidiurnal tidal oscillation. Tracks of drifting stations during 20 yr define the Beaufort gyre circulation, the center of which, 80 W, 140 W, coincides with that of a mean atmospheric pressure anticyclone. West of 140 W, the dominant W and N drifts are segments in the Transpolar Drift Stream; east of 140 W, where drifts are mainly E to W, they are in the eastern Beaufort gyre. Ice drifts faster in the Transpolar Stream than along the Canadian Islands by about 1/2 nautical mi/day; a marked increase in speed occurs in summer or fall; the atmospheric pressure gradient variations agree qualitatively with the drift speed variations. Three experiments needed to solve the principal remaining problems are explained.

The detection and measurement of CO 2 in air bubbles entrapped in ice originated with Per F. Scholander in 1954, predating the studies referred to in Broecker (1982), Geochim. Cosmochim. Acta 46, 1689–1706.