Abstract:
One objective of the U.S. Southern Ocean Global Ocean Ecosystems
Dynamics (SO GLOBEC) program is to gain a better understanding of the
sea floor bathymetry in the program study area. Much of Marguerite Bay
and the adjacent shelf west of the Antarctic Peninsula were poorly charted
when the SO GLOBEC program started in 2000. Before the first SO
GLOBEC cruise, an improved local area version (ETOPO8.2A) was created
from the Smith and Sandwell (1997) topo_8.2.img 2-minute digital gridded
bathymetry for the study area. The first SO GLOBEC mooring cruise on
the R/V Lawrence M. Gould (March 2001) showed that the 2-minute spatial
resolution of ETOPO8.2A did not resolve many of the canyons and abrupt
changes in topography that characterize Marguerite Bay and the inner- to
mid-shelf region. It also was not particularly accurate in the more uniform
terrain regions. We then decided to collect as much multibeam bathymetry
data as possible during the SO GLOBEC broad-scale survey cruises on the
R/VIB Nathaniel B. Palmer and combine these data with all other
available multibeam and trackline bathymetry data to construct a digital
bathymetry database and map for the study area. The resulting database
has high-resolution data over much of the shelf and parts of Marguerite
Bay gridded at 2 seconds in latitude and 6 seconds in longitude spacing
between 65° to 71° S and 65° to 78° W. This technical report describes the
steps taken to assemble and construct this database and how to access the
data via the Internet.
