SeaBASS

Questions we often get asked.

High quality in situ measurements are prerequisite for satellite data product validation, algorithm development, and many climate-related inquiries. As such, the NASA Ocean Biology Processing Group (OBPG) maintains a local repository of in situ oceanographic and atmospheric data to support their regular scientific analyses. The SeaWiFS Project originally developed this system, SeaBASS, to catalog radiometric and phytoplankton pigment data used their calibration and validation activities. To facilitate the assembly of a global data set, SeaBASS was expanded with oceanographic and atmospheric data collected by participants in the SIMBIOS Program, under NASA Research Announcements NRA-96 and NRA-99, which has aided considerably in minimizing spatial bias and maximizing data acquisition rates. Archived data include measurements of apparent and inherent optical properties, phytoplankton pigment concentrations, and other related oceanographic and atmospheric data, such as water temperature, salinity, stimulated fluorescence, and aerosol optical thickness. Data are collected using a number of different instrument packages, such as profilers, buoys, and hand-held instruments, and manufacturers on a variety of platforms, including ships and moorings.

MOBY (Marine Optical BuoY) radiometry data are regularly used by the NASA OBPG as part of ocean color validation and vicarious calibration activities. MOBY is an autonomous buoy moored off of the island of Lanai in Hawaii. Each day it is deployed it collects several measurements of upwelling radiance from sensors on its underwater arms (at approximately 1, 5 and 9 m depth) and downwelling irradiance from sensors on its underwater arms as well as at the surface. More information about MOBY can be found on the MLML site and NOAA site.

 

Standard metadata headers are required in every SeaBASS file. Select a header to view its definition. Some headers are required in all SeaBASS files, some are conditionally required depending on what type of data were measured, and others are optional.

 

If you are getting started learning about SeaBASS file format, scroll down below the table of contents to see an example header.

This page provides examples of data files and documentation as models to help you format different types of submissions. Measurement-specific metadata, formatting, and accompanying documents are highlighted.  For each data type found in the menu below, note the sections on "Special Requirements" and "Example Submission".

 

The Special Requirements sections indicate any conditionally required metadata headers needed for specific types of data. Additionally, check for any Required Extra Documents. Those should be filled out and submitted with your other documents and calibration files. These checklists were designed to standardize and preserve critical methods and analysis details that are needed for intercomparison, reprocessing, to make it easier for data users to assess the data quality and to consider them for satellite validation or inclusion in algorithm development datasets.

 

The Example Submission sections include one or more example SeaBASS data files that might be helpful as a reference for which fields and headers to include, and how to arrange your data matrix. Examples of documents and calibration files that were part of a model submission are also provided.

 

Over time additional examples will be added.

 

To assist with the standardization of SeaBASS data files, the SIMBIOS Project developed feedback software, named FCHECK, to evaluate the format of submitted data files. Since then, it has been rebuilt from the ground up by the SeaBASS development team to make it available to the end-users. There are multiple ways to access this software, as explained further below. Using FCHECK, contributors may evaluate the format of their SeaBASS-compatible files prior to submission.

 

FCHECK scans files for common syntax problems, missing header information, data values outside of typical ranges, nonstandard field names or units, and also detects various other issues. It will report a summary of the types of problems detected (if any) among all the files it scanned, as well as a more detailed breakdown of issues found in each individual file. Problems are classified as either errors or warnings, depending on their severity. Errors are critical problems that must be addressed before files can be archived. Warnings should be fixed if possible, but some of them are subjective or optional and may be disregarded.

These validation match-up tools allows Users to

These tools are downloadable for Users to run individually, external to the official SeaBASS validation search. These tools are designed to replicate some of SeaBASS validation search's core functionality, with the exception that these tools do NOT adjust in situ data to water-leaving values.

 

These validation match-up tools are served as part of SeaDAS and apply the default recommended match-up exclusion criteria, as set forth in S.W. Bailey and P.J. Werdell, "A multi-sensor approach for the on-orbit validation of ocean color satellite data products", Rem. Sens. Environ. 102, 12-23 (2006).

Access to the data archived within SeaBASS follows the NASA Earth Science Data and Information Policy. 

NASA's Earth Science program was established to use the advanced technology of NASA to understand and protect our home planet by using our view from space to study the Earth system and improve prediction of Earth system change. To meet this challenge, NASA promotes the full and open sharing of all data with the research and applications communities, private industry, academia, and the general public. The greater the availability of the data, the more quickly and effectively the user communities can utilize the information to address basic Earth science questions and provide the basis for developing innovative practical applications to benefit the general public. In this regard, all users incorporating SeaBASS data into their research are expected to acknowledge both their data sources (the original data contributors and SeaBASS) and NASA, and to abide by the Access Policy.