Recent bathymetric charts and maps of the Southern Ocean and waters around Antarctica

Abstract

-Some recent bathymetric charts and maps of the Southern or Antarctic Ocean are discussed and some comparisons made between the various interpretations of the relief of the ocean floor. Reference is made to the nomenclature of features on the sea bed, and also to certain aspects of the continental shelf of Antarctica. WITH the advent of the International Geophysical Year interest has again been aroused not only on Antarctica but on the waters which surround it. Recent new editions of exiting bathymetric charts and maps, and an entirely new map, have brought into prominence the amount of work already d o n e often under difficult conditions t o determine the relief of the bed of the Southern Ocean, and of the continental slope and shelf surrounding the continent. Many authorities have contributed towards the knowledge which we now possess of the sea bed of the Southern Ocean. Much of it is still largely unexplored but there can be little doubt that it was the comprehensive oceanographical survey, begun here in 1925 by the former Discovery Committee, and continued later by the National Institute of Oceanography, which has produced a sufficient density of soundings to form the basis for the bathymetry of the charts and maps now under review. These fall into two quite distinct categories, i.e., that in which the primary object has been to contour a wide area of the ocean floor around Antarctica*-~ and that in which the delineation of the coasts and of known features on the Continent itself takes precedence, §. In the latter charts, (or more correctly maps), depth contours have been drawn in at standard intervals for some distance seaward of the land, and the maps thus have an additional value in that features on the sea bed adjacent to or on the continental shelf can often be related to the topography of the continent itself. On account of the long intervals of time which elapsed between the publication of the earlier editions of the bathymetric charts * t and the map :~, and the great differences in the number of soundings plotted, any comparison between the various interpretations of the relief has not previously been considered, nor indeed, would it have been profitable. Now, we have not only a new (the 3rd) edition of the U.S.H.O. Chart No. 2562 of Antarctica, but an almost complete new edition of the International Hydrographic Bureau's Bathymetric Charts south of 46 ° 40'S (series B t and Ct). In addition, there is the recently published 2nd edition of the Australian map of Antarctica and the new Karte der Antarkt is , recently published in Germany. • United States of America, Navy Department Hydrographic Office, Washington, D.C., 1955. Chart No. 2562 (Antarctica). tlnternational Hydrographic Bureau, Monaco, 1952-55. Cartes Grnrrale Bathym&rique des Ocrans, feuilles Bq-IV, Cln, ni. :[:Map of Antarctica (1939) 2nd edition, 1956. Department of External Affairs, Commonwealth of Australia. §HANs-PETER KOSACtt 0955) Karte der Antarktis Geographisch-Kartographische Anstalt Gotha.