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VIIRS Ocean Color Tutorial

Posted: Thu Apr 04, 2013 12:41 pm
by gumley
This tutorial describes how to install and run SeaDAS 7.0beta to create Ocean Color products from VIIRS SDR files created by CSPP. The script files and data described in this tutorial are available at

Note that SeaDAS 7.0beta does not create Sea Surface Temperature (SST) products. This capability will be available in an upcoming release of CSPP VIIRS EDR.

1. To install SeaDAS 7.0beta, run the install script as shown below (note: 64-bit Intel Linux host computer is assumed). Approximately 3.5GB of hard drive space will be used in your home directory.

chmod u+x install_seadas.bash

When you see the 'Select Components' dialog box, check the boxes labelled 'Linux64', 'Common processing files', and 'VIIRS'. This will download the SeaDAS 7.0beta software package from NASA OBPG, and install it in your home directory. It will also update the SeaDAS package. To install it in a different directory, just edit the install script.

2. Run the SeaDAS Level 2 ocean color code on the test data. Note that the run script is executed once for each granule of VIIRS SDR data. The run script will handle aggregated SDR granules created using CSPP (-a option in

chmod u+x run_viirs_seadas.bash
./run_viirs_seadas.bash data/SVM05_npp_d20130331_t1802568_e1804210_b00001_c20130331182137542989_cspp_dev.h5

This will create temporary uncompressed copies of the VIIRS M-band SDR and geolocation files, run the SeaDAS ocean color retrieval code, and write the output file in HDF4 format. Note that the h5repack utility is distributed with the CSPP SDR software package.

3. Now you can visualize the SeaDAS chlorophyll product. In the example below, we use IDL for this purpose.

IDL> !path = 'idl:' + !path
IDL> seadas, 'SEADAS_npp_d20130331_t1802568_e1804210.hdf'