Distribution of particle size in suspension at various depths from San Pablo Bay and Grizzly Bay, California, 2020

These data present suspended particle size distributions collected by the U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center within two embayments of San Francisco Bay. Data were collected at one site in San Pablo Bay and one site in Grizzly Bay from January through February 2020 by deploying a Sequoia Scientific Laser In-situ Scattering and Transmissometry instrument (LISST 200x) from a small vessel near pre-established USGS instrument moorings. At both sites, data were collected on four dates at three depths, generally near the water surface, at mid depth, and near the sediment bed, for 1-3 minutes at each depth. LISST volume concentrations are most accurate when the optical percent transmission is above 30; when this is true, light passing through the sample volume is unlikely to be scattered by more than one particle. These files contain all samples collected; judgment should be applied when using them. Users are advised to check metadata and instrument information carefully for applicable time periods of specific data.