Bathymetry of Lake Ontario
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On-line store: Poster (50x36 in), CD-ROM |  |
Free Downloads |
DATA ANNOUNCEMENT 2000-MGG-01 revised May 2001
The National Geophysical Data Center announces a full color poster measuring 50" by 36"depicting the bathymetry of Lake Ontario. Included with the poster are color diffracting glasses for viewing in 3-D. The poster has a scale of 1:275,000 in a Transverse Mercator projection and with 2 meter contour intervals. This bathymetry resolves physiography of the lake floor to the extent that known features are revealed more accurately, and features never before seen are revealed. For example, what has been called the Charity Shoal can now be seen as a near circular depression with a rim having downward relief on both sides.
A custom 3 foot by 5 foot wall size poster of Lake Ontario bathymetry is also available at a scale of 1:250,000.
Preparation and Supporting Data of the New Bathymetry
This new Lake Ontario dataset is the third in a series of five depicting the bathymetry of the Great Lakes - the other two being Lake Michigan (1996) and Lake Erie (1998). The new Lake Ontario bathymetry was a collaborative effort between scientists at the NOAA National Geophysical Data Center (NGDC), the NOAA Great Lakes Environmental Research Laboratory (GLERL), the Canadian Hydrographic Service, and the University of Colorado Cooperative Institute for Research in Environmental Sciences (CIRES).
The entire historic hydrographic sounding data base from the U.S. and Canada, originally collected for nautical charting purposes, was used to create a complete and accurate representation of Lake Ontario bathymetry. The U.S. data primarily came from the NOS Hydrographic Survey Data, U.S. Coastal Waters CD-ROM Set (Version 4.0, Data Announcement 98-MGG-03). This and other bathymetric sounding data collected by the U.S. National Ocean Service's (NOS) Coast Survey and the U. S. Army Corps of Engineers was employed to construct bathymetric contours at 1 meter intervals from 1-10 meters depth and 2 meter intervals at depths greater than 10 meters. Compilation scales ranged from 1:10,000 to 1:50,000. Bathymetric sounding data collected by the Canadian Hydrographic Service (CHS) were employed to construct bathymetric contours at 1 meter intervals and compilation scales ranging from 1:1,000 to 1:30,000. Digitization of the bathymetric contours, merging of the bathymetric contour data sets, poster construction, and preparation of a CD-ROM, were accomplished at the NGDC. Multibeam bathymetric data collected by the University of New Brunswick's Ocean Mapping Group (UNB-OMG), with support of the Geological Survey of Canada (GSC) and the CHS, were kindly made available in gridded form. In two areas where multibeam bathymetric data were made available, no other bathymetric data were used in the compilations. In some areas all available Canadian and U. S. bathymetric sounding data, collected at different times on different survey expeditions, were used to derive the contours.
AVAILABILITY
NGDC has the capability of generating custom graphics for specific regions. These custom graphics are available as digital files, paper prints, transparencies, or 35 mm slides. For more information and prices associated with custom graphics, please refer to the contacts listed below.
More information on Lake Ontario
For more information on the Great Lakes Data Rescue Project, see the
Great Lakes Data Rescue Project WWW Page.