SO503, Spring 2003

Digital Bathymetry Properties Lab

You should run the "Update_PC" batch file on the J drive before proceeding.

We will run the program from the c:\guthprog\microdem directory.  Any other locations on the computer will have an old version of the program and help file, and will cause you problems.  

We have the following digital bathymetry sets.  Except for the Smith & Sandwell data set, which has its own icon on the MICRODEM toolbar, they will all be in c:\mapdata\bathylab.

• ETOPO5, world wide coverage
• Smith & Sandwell's predicted bathymetry, world wide coverage
• Annap_bathy, NOAA estuarine data near Annapolis.
• Axial, NOAA data for a volcano on the Juan de Fuca ridge.
• ECBathy, the continental shelf
• Mont-SHP, NOAA data off Monterey

Perform a visual examination of the DEMs.  Look at the product gallery in the MICRODEM help file for suggestions on how you can look at this data.  Insure that you understand the difference between the apparent resolution you see on screen, and what is actually available with the data.  The "1:1" button may be useful for this concept.  Which DEMs do you think are the best, and why?

For next week's lab submission, write a discussion that addresses these points:

• Prepare a table listing the DEMs, their resolution, and the required computer storage to store one square degree.  Discuss any limitations or caveats that go with your estimates.
• What are the costs and benefits of increasing the resolution?  Is there a best resolution?
• What determines the size of a DEM (the file you download)?