GEODAS uses a series of Coastlines files when it graphically displays maps. Currently 3 different coastlines are used. These coastlines come with all GEODAS CD/DVD sets. The files are all in GEODAS 2-D Vector Format VCT00, which allows for multiple resolutions within the coastline file. GEODAS software takes advantage of the different resolutions, plotting the appropriate level of resolution automatically. Additionally the GEODAS Coastline Extractor application allows the user to determine the coastline file and it's resolution for plotting and/or saving. If you desire to plot and/or save a different coastline you may use the Choose Coastline Dialog to change the coastline/resolution from the default. Be aware that using a higher resolution coastline for a large area plot will result in longer plotting time and rather large saved files.
The GEODAS Coastline files installed are:
hersey.b00 - Worldwide Hersey Low Res. 1:120 million
wvs1mres.b00 - World Vector Shoreline subset at 1:1million resolution (altered)
nosconus.b00 - NOS Medium Resolution Continental US shoreline (altered)
The data provided are an historical data set, and as such they may not always reflect current conditions. Thus the data are NOT TO BE USED FOR NAVIGATION PURPOSES.
Except for the Great Lakes region (see below), the source of these data are the U.S. NOAA/NOS Medium Resolution Vector Shoreline of U.S. waters. (obtained as ARC/INFO export files which has a geographic projection with GRS1980 spheroid as a reference (decimal degrees) (obtained the files, *.gz, online at www.ngdc.noaa.gov/mgg/shorelines/noaamrdvs.html)
The Great Lakes portion of the NOS Medium Resolution Shoreline was replaced by Great Lakes shoreline data compiled at NGDC. This Great Lakes shoreline data compiled at NGDC was added to the World Vector Shoreline file. The Lake Michigan shoreline is from the U.S. NOAA/National Ocean Service's(NOS) Medium Resolution Vector Shoreline of U.S. waters(www.ngdc.noaa.gov/mgg/shorelines/noaamrdvs.html). The Lake Erie shoreline is from the Bathymetry of Lake Erie and Lake Saint Clair CD/DVD, GEODAS volume G1, 1999, Lisa Taylor.
The Lake Ontario shoreline came from the Canadian Hydrographic Service (CHS), NGDC digitized contours, the U.S. NOAA/GLERL Medium Resolution Vector Shoreline of the Great Lakes (Lee, et als., 1998), and the U.S. NOAA/NOS Medium Resolution Vector Shoreline of U.S. waters.
Lakes Superior and Huron shorelines are from the U.S. NOAA/Great Lakes Environmental Research Lab's(GLERL) Medium Resolution Vector Shoreline of the Great Lakes (Lee, et als., 1998). (ftp.glerl.noaa.gov/gis/shoreline/) These two lake coastlines will probably change as we push forward to complete new contours for these lakes.
Lee, D. H., C. Morse, and D. Bandhu, 1998, Great Lakes and St. Lawrence River Medium Resolution Vector Shoreline Data, NOAA Technical Memorandum NOAA ERL GLERL-104.
For additonal information on the NGDC's Great Lakes coastlines contact William.T.Virden@noaa.gov.
WVS is a digital 1:250,000 scale NIMA (National Imagery and Mapping Agency) product in ASCII coded Standard Linear Format (SLF) that has been in existence since the late 1980's. It contains shorelines derived from Digital Landmass Blanking (DLMB) data and supplemented by Operational Navigation Charts (ONCs) and Tactical Pilotage Charts (TPCs). It also contains international boundaries and country names derived from paper products including ONCs, TPCs, and Joint Operation Graphics (JOGs). More information on this coastline can be found at www.esri.com/library/userconf/proc97/proc97/to350/pap339/p339.htm