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Water Quality of San Francisco Bay
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Notice: The database server for this site is currently offline, to access data please read:

I. Directly measured parameter data (depth, chlorophyll-a, dissolved oxygen, SPM, extinction coefficient, salinity, temperature, nutrients) are available for download in csv files:

  • 1969-2015 data
  • 2016-2019 data
  • Scientific Data article with detailed data descriptions

    II. Calculated parameters (chlorophyll ratio, oxygen % saturation, Sigma-t) are available upon request. These variables are defined on our data description page.

    Contact Erica ( for data requests or questions

    Metadata are included in the data products linked above and the Scientific Data article. Also please see the data descriptions, glossary, and general overview of the sampling program.

    Data Caveats:

  • 2014-2018 Si were corrected 0-10% October 2019.
  • Si data are not available for 2011 - Feb 2014
  • NO2 data are not available for 2005 - 2011
  • Light attenuation data are not available for 2002 - 2006
  • Sigma-t was not calculated prior to November 1987
  • CTD sampling began Nov 1987, since this time discrete data are collected and listed at 2m and/or bottom depth, and light extinction coefficient is listed on the 1m line, or the surface depth if not 1m. Prior to Nov 1987 discrete parameters were collected at variable depths (commonly 0.5m, 1m, and 2m) and light extinction coefficient is list at 0.5m, 1m or 2m.
  • Time of day values for cruise data sampled 1981 through 1987 are accurate within +/- 30 minutes

    Please let us know if you are using our data in any publication (email, it helps us keep this program going

  • Hooking up CTD Image

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