Nearshore Canyon Experiment Bathymetry and Topography



Bathymetry and Topography for the nearshore canyon experiment area has been obtained from different sources. The data have been combined into a uniform grid for use by NCEX investigators. This grid will evolve over time as new bathymetry data are obtained or errors are corrected. The purpose of this web page is to describe the data sources and gridding process, and provide updated grid files with documented changes.

With each grid update, the data files will be assigned a new version number, and will be referred to by a progressing grid number: Grid 1, Grid 2, etc. The grid data are provided in several formats and these will remain consitent with each update of the grid data. Additional grids may be added over time if needed or desired.

The initial grid, created by Mark Orzech at NPS and distributed by Steve Elgar through May 2002, is "NCEX GRID 1".
Horizontal Data Convention: Latitude and Longitude (WGS84)

Vertical Data Convention: meters from MSL. Water depths are positive, land elevations are negative.



The Bathymetry Grids

Grid format description and code to read/view grids.

1.NCEX Grid 1. Original grid by Mark Orzech at NPS.

2.NCEX Grid 2. Created July 2002.
Removes numerous data outliers and adds coastal land elevations.

3.NCEX Grid 3. Created April 2003.
Adds additional CBASS survey data around the south branch of the north canyon head, SHOALS data in shallow water south of SIO pier, and USGS swath survey data for the deep portion of the canyon offshore.

4.NCEX Grid 4. Created August 29, 2003.
Updates shallow water bathymetry from SIO pier northward past Blacks using CBASS August 20-22, 2003 mini-grid survey data.




Description of data sources.

Description of the gridding process.