Nearshore Canyon Experiment Bathymetry/Topography
Gridding
The processing of the raw survey data into a grid is done as follows:
- Outliers were removed from each data set.
- The edited data was sorted by latitude and duplicate points (data
with same lat,lon) were removed.
- Delaunay tesselation was used to create a faceted surface of triangles
from the data where the triangles are as equiangular as possible. The
grid points were linearly interpolated from the surfaces of the triangles.
Areas with widely spaced or no data were excluded by restricting the
maximum size of triangles that could be passed to the grid interpolation
subroutine.
In the creation of NCEX Grid 1, all the survey data was combined into
a single data set before gridding. For NCEX Grid 2, each data set was
gridded individually, and the resulting grids overlaid, worst surveys
first, best surveys last, to form a final grid.
Horizontal Data Convention: Latitude and Longitude (WGS84)
Vertical Data Convention: meters from MSL. Water depths are positive, land elevations are negative.