Physical and biological data linked to stratification events in Suisun Bay, CA

This data release contains all collected data sampled during vertical stratification events, as well as during times of vertical mixing within and around Suisun Cutoff, in Suisun Bay, CA. Data were collected using a holistic approach spatially and temporally, looking at hydrodynamics, biotic compositions, and water biogeochemistry throughout the water columns at designated points in Suisun Bay between September 22 and October 3, 2025. Sample data were collected either at points around Suisun Cutoff or by stationary sampling at an established sample site (USGS station 380530122003101, Suisun Cutoff A Simmons Island CA).
Data streams from this effort include: biota community composition sampling from zooplankton net tows around Suisun Cutoff with a depth-integrated zooplankton net; high-resolution water quality mapping around Suisun Cutoff; water quality vertical profiling around Suisun Cutoff, FluoroProbe monitoring at a single location in Suisun Cutoff; a mobile, downward-facing BioSonics echosounder for detections of organics and biota around Suisun Cutoff; a stationary upward-facing Multi-Frequency Echosounder and Acoustic Doppler Current Profiler (MFE-ADCP) at the sample site; stationary continuous water quality Yellow Springs Instrument (YSI) sonde records at the sample site; stationary point sampled water quality with an RBR (originally named for Richard Brancker Research) sonde and particulate optics with a Laser In-Situ Scattering and Transmissometry (LISST) optical sensor at the sample site; recording of weather conditions that may impact other data at the sample site; and stationary discrete sampling for particulate organic matter (POM) isotopic content that were collected at the sample site. USGS Water Data for the Nation (WDFN) sample information on suspended sediment concentrations (SSC) and concentrations of chlorophyll-a (Chl-a), phaeophytin, total particulate carbon (PC), particulate organic and inorganic carbon (POC and PIC), particulate nitrogen (PN), and total suspended solids (TSS) collected at the sample site are also included in this data release. Please see the Process Steps in the Stratification_SuisunBay_Metadata.xml document to view parameter and method codes.
Detailed descriptions of sampling methods and processing to develop each data stream can be found in the Process Steps sections of the ‘Stratification_SuisunBay_Metadata.xml’ document. A description of how to access each data stream in this data release can be found in the Overview section of the Stratification_SuisunBay_Metadata.xml document. Entities (files) and attributes (columns/fields) for each file with the data streams can be found in the DataDictionary.csv document, and for the MFE_ADCP_Raw.h5 file, attributes can be found in the MFE_ADCP_DataDictionary_Raw.h5.csv document.
The stationary upward-facing echosounder data file for this data release is large and requires 200 GB storage space for download. Additionally, raw data for the two mobile downward-facing echosounders are provided for user interest in their original .dt4 format in the MobileAcoustics_Data compressed zip folder and can be accessed through an echogram-compatible software such as the freely available Microsoft Windows-based VisualAcquisition6 (developed by BioSonics, Inc see Note below).
Note: Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.