Caution: These data are outdated. Please download desktop software under "Related Links" below to extract updated data from GSHHG.
The Coastline Extractor was created by Rich Signell of the U.S. Geological Survey / Geologic Division / Coastal and Marine Program / Woods Hole Field Center. The extractor pages are currently hosted by the NOAA/National Geophysical Data Center, Marine Geology and Geophysics Division.
Caution: These data are outdated. Download desktop software under "Related Links" below to extract updated data from GSHHG.
The electronic form above allows you to extract coastline segments bounded by a specified latitude/longitude range. Also produces a "page size" screen plot of the coast you extracted in a cylindrical-equidistant projection.
The selected data returned by the query is an ASCII flat file with two columns containing longitude and latitude in decimal degrees (west negative). The default GMT ASCII format is lon, lat with new segments separated by a line containing the character ">". The MAPGEN format is lon, lat with new segments separated by a line with characters "# -b". The MATLAB format is the same, but with the characters "nan nan" indicating line breaks, so in MATLAB you can type "load coast.dat" then "plot(coast(:,1),coast(:,2)". The Arc Ungenerate format works with ArcGIS®.
ArcView will not read the Ungenerate format directly, but you can convert from Ungenerate to a Shape file that ArcView can read using the script gen2shap1.ave. For MAPINFO users, there is a tool CoastCon.zip from Peter Lyngs that converts the MAPGEN format output to MapInfo Import Files (MIF).
The ASCII files may be compressed in a variety of formats before downloading.
The default values below will give you the WVS coastline for Cape Cod, Marthas Vineyard and Nantucket in Massachusetts, USA.About the data sets:
Our processing details may be found here.
Note: If you are interested in making the coastline continuous and you have Matlab, click here.
pages maintained for Rich Signell by: NOAA/NGDC Marine Geology and Geophysics Division