During the accessioning process, NODC created four files to include as
additional metadata for this data collection. These files include a list
of all latitude-longitude pairs for observations, bounding values that
indicate the northernmost, southernmost, easternmost and westernmost
boundaries of the data, and graphical plots of all data locations in a
.jpg and .ps format.

The accession number assigned by NODC is depicted in each file name as
#######. The files use the following naming conventions:

#######_lonlat.txt - this file is created by extracting the longitude
and latitude values for all station locations in the data. The list of
longitude-latitude pairs is then processed to remove duplicate stations
and to reformat the values to decimal degree formats, if necessary. The
left column contains longitude values, the right column contains latitude
values.

In accordance with FGDC guidelines, North latitude and East longitude are
positive values, South latitude and West longitude are negative values.

#######_box.txt - this file is generated by a processing script
developed at NODC that analyses the values in #######_lonlat.txt and
outputs the northernmost, southernmost, easternmost and westernmost
values.

#######_map.jpg - this JPEG file is created by plotting the values in
#######_lonlat.txt using the unix plotting software Generic Mapping
Tools (GMT).

#######_map.ps - this PostScript image file is created by plotting the values in
#######_lonlat.txt using the unix plotting software Generic Mapping
Tools (GMT). 

For more information about GMT, please see http://gmt.soest.hawaii.edu/
(last accessed on 2006-01-27).