Woods Hole Science Center
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At this stage, each enclosed polygon will be masked out as land. As it does so, the progress will be stated. It is at this stage of that the requirement for simple closed coastlines becomes critical. If they are not simple closed, the gridding stage will fail.
After the masking completes, the grid will be fitted with bathymetry. The algorithm employed uses an inverse distance weighting scheme along with a search radius around each grid point. Supply the number of bathymetry points in each quadrant around a grid point along with the radius out from said point to search for the bathymetry points. For this tutorial, chose 1 point per quadrant, and 20 km for the search radius.
Next you will be asked if you wish to clip the bathymetry above or below certain depth values. Type in "2 200" to indicated a minimum of 2 m and a maximum of 200 m in the output grid.
And finally, you are asked for the file format in which to save the grid, either ECOM or SCRUM. Choose whichever. When the save operation is complete, you are finished! A window will pop up showing something like
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U.S. Department of the Interior |
U.S. Geological Survey
URL: woodshole.er.usgs.gov/operations/modeling/gridgen/masking.html
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Page Last Modified: Monday, 12-Feb-2007 07:38:06 EST
