HR: 0800h
AN: C21A-0974 [Abstracts]
TI: The International Bathymetric Charts of the Arctic and Southern Oceans: Setting the Physiographic
Context for Marine Research During IPY.
AU: * Macnab, R
EM: ron.macnab@ns.sympatico.ca
AF: Geological Survey of Canada (Retired), 11 Lyngby Avenue, Dartmouth, NS B3A 3T6
Canada
AU: Jakobsson, M
EM: martin.jakobsson@geo.su.se
AF: Stockholm University, Department of Geology and Geochemistry, Stockholm, 10691
Sweden
AU: Schenke, H W
EM: hschenke@awi-bremerhaven.de
AF: Alfred Wegener Institute for Polar and Marine Research, Bathymetry and Geodesy Group
Postbox 120161, Bremerhaven, D-27515
Germany
AB:
As international bodies whose functions include the overview and coordination of polar research, IASC and SCAR are actively
promoting, planning, and in some cases sponsoring cooperative scientific activities within the IPY context. Among these
activities is the development of accurate bathymetric data bases and maps that describe the depth and morphology of the polar
seabeds. Constructed from all the available sounding information that can be assembled and rationalized, these maps not
only respond explicitly to the needs expressed in IPY Theme 1 (to determine the present environmental status of the polar
regions by quantifying their spatial and temporal variability), but they provide essential background information for
multiple investigations that are central to the attainment of objectives in IPY Themes 2, 3, and 4. For instance, detailed
physiographic descriptions of the seafloor can provide contemporary and historical indicators of sea level change, of
constraints to ocean circulation, and of processes associated with glaciation, sedimentation, and tectonic activity.
In recent years, an international team has operated under the auspices of IASC, IOC, and IHO, to develop the International
Bathymetric Chart of the Arctic Ocean (IBCAO). The First Edition of IBCAO is now available in printed and digital form, with
future improvements planned as new sounding information becomes available. Similarly, a new team sponsored by SCAR, IOC,
and IHO has just launched an Antarctic analog to IBCAO: the International Bathymetric Chart of the Southern Ocean (IBCSO).
The initial objective of IBCSO is to develop a preliminary description of the seabed adjacent to Antarctica prior to the
launch of the IPY, for use in planning scientific field work and for guidance in collecting depth observations in areas where
soundings are scarce. A longer-term objective is to promote the systematic mapping of the Southern Ocean in order to
complement existing data holdings, and to supplant existing seabed portrayals that have been derived from observations of
satellite altimetry, but which are limited in accuracy and resolution. Similarly, it is hoped that IPY undertakings in the
Arctic region will stimulate the collection of new depth observations that can be used to enhance IBCAO.
This presentation will highlight selected features of IBCAO and IBCSO, suggesting how their contents can assist IPY
investigators and indicating where improvements can be expected as a result of IPY activities.
DE: 4207 Arctic and Antarctic oceanography
DE: 3022 Marine sediments--processes and transport
DE: 3040 Plate tectonics (8150, 8155, 8157, 8158)
DE: 3045 Seafloor morphology and bottom photography
SC: Cryosphere [C]
MN: 2004 AGU Fall Meeting