Downloading, decompressing, and reading WOD data
For technical help or to report problems, please e-mail OCL.help@noaa.gov
WOD data are accessible through interfaces that sort data geographically and by date in native ASCII format presorted by 10° geographic squares and by year. The WOD data format description can be found in detail in the WOD documentation.
Downloading individual data files:
All the WOD ASCII output files are in GZIP
compressed format.
However, the user should be aware that different web browsers handle GZIP compressed files differently.
MOZILLA USERS:
Can download the
data file in two ways: (1) hold the "shift" key and click on the link
to the data file or (2) right-mouse click on the link and select the
"Save Link Target As ..." option.
INTERNET EXPLORER USERS:
Can
download the data file by copying the link location to your browser
and then saving the file in your local working directory.
Decompressing data:
After downloading the data file, to uncompress the file the user can use any software which can handle zip-archives,
such as WinZip, WinRAR, StuffIt, MacZip, UnZip, etc.
After downloading and uncompressing the file, you can view the data
using any ASCII text editor.
Reading WOD native data format:
The WOD data format description can be found in the WOD documentation.
The data format is comprised of several sections
including primary, secondary, variable-specific second headers,
character data, taxa-specific and biomass data, and
measured variables.
NOTE: WOD native ASCII format has been altered slightly to accomodate the changes to the standard depths since WOD13 release. There is a 'C' in the first byte of each cast instead of a 'B' as for World Ocean Database 2009. Provided example programs have been updated to reflect this change.
The WOD native data format can be read in a number of ways:
(1) The user can use any of a number of WOD Programs (see Documentation section) in FORTRAN and C to read the WOD native data format or the user can write his/her own code. The programs provided are designed as examples on how to read the WOD data for all types of datasets and convert data into a form useable in Matlab and ArcGIS. The sample programs prompt the user to input a data file to read casts and variables included in these casts to the screen. Note that the user needs to modify the programs to incorporate user specific needs such as single or multiple input data files, output file(s), number of cast, data output format and number of variables. The metadata codes listed within each cast are described in the code tables.
(2) The user can also use the Ocean Data View (ODV) software package to read the WOD native format and display the data.
NOTE: No prior version will read WOD data. Ocean Data View 4.5.7 has been updated to read the amended format (WOD13 and later releases).
The latest version is available from ODV website. The user will need to open a new ODV collection (or add to an existing ODV collection) and specify "World Ocean Database Variables" in the "Definition of Collection Variables" menu. The detailed instructions are available from WOD tutorial (pdf, 0.1 MB). Note that ODV will not be able to read surface only data; originator's quality flags; or plankton biomass and taxonomic data in the OSD file.