Table of Contents

• Dataset Description
  • Methods & Sampling
  • Data Processing Description
• Data Files
• Parameters
• Instruments
• Deployments
• Project Information
• Funding

Santa Cruz Municipal Wharf Shore Station
36deg 57'38.3""N  122deg01'13.1""W
YSI 6600v2 Sonde: Temperature, Salinity
Satlantic SeaFET: Internal pH, External pH, Temperature
Fixed intake depth, approx. 1 m

Sampling and Analytical Methodology:
Fixed shore station with pumped seawater from ~1 m depth; YSI 6600v2 sonde and Satlantic SeaFET in the flow through, sampling at 5 minute intervals. Instruments configured/deployed as per manufacturer recommendations. pH from the SeaFET was compared to discrete measurements analyzed by Andrew Dickson’s laboratory (SIO). Calibration curve applied to the data.

Data Processing:
Obvious outliers were removed; missing data replaced with -999. Pre- and post-deployment calibration applied to salinity and pH data.

Discrete samples (used for calibration) and continuous data submitted to the SWAMP and CEDEN databases: http://www.ceden.org

BCO-DMO Processing Notes
 - Generated from original file: "SoCalPlumeEx2012_SCW_pH.csv" contributed by Raphael Kudela
 - Parameter names edited to conform to BCO-DMO naming convention found at Choosing Parameter Name
 - Date reformatted from MM/DD/YY to YYYYMMDD
 - Time reformatted from HH:MM to HHMM
 - Latitude/Longitude and depth appended from original file

In autumn 2012, Orange County Sanitation District (OCSD) will divert ~150 million gallons/day of secondarily-treated effluent to a nearshore (1 mile offshore) outfall pipe over a period of ~4 weeks. No discharges of this magnitude have been conducted in decades. The planned diversion is expected to create a buoyant surface plume that will spread over much of the coastal region. Because OCSD plans to "super-chlorinate" and then dechlorinate the discharge, the effect of the plume should be predominantly a nutrient addition rather than direct addition of intact microbial populations. The PIs propose to address two broad questions through a study of the plume:

First, what happens ecologically and physiologically to the phytoplankton assemblage when nutrients are discharged in the surface ocean for extended periods of time?
Second, can this dynamic and shifting environment be sampled by deploying multiple technologies to identify the physical/chemical drivers of the biological response at ecologically relevant space and time scales?

They will test two hypotheses:
H1: Continual discharge of nutrients to the surface ocean results in a dinoflagellate-dominated bloom which leads to dampening or cessation of vertical migration of the dinoflagellates and drives a shift to net heterotrophy.
H2: The bloom will initially result in a strong local sink for carbon dioxide which gradually develops into a strong source as heterotrophy develops.

The study is expected to provide a time-evolving picture of interactions within and between autotrophic and heterotrophic communities and will illustrate the short-term biogeochemical and ecological consequences of sustained nutrient discharge to a shallow coastal site. The planned diversion provides an unprecedented opportunity to study the ecophysiological response in a natural setting over a period of weeks, including the interaction of biology, chemistry, and physics, and it will contribute to basic understanding of anthropogenic nutrient loading to the coastal ocean. Undergraduate and graduate education and training will be furthered through active participation in lab, field, and data synthesis activities involving academic, government, and industry partners.

Affiliated Programs or Projects:
- NOAA ECOHAB Project (NA11NOS4780030): A Regional Comparison of Upwelling and Coastal Land Use Patterns on the Development of HAB Hotspots Along the California Coast
- Southern California Coastal Ocean Observing System
- Central and Northern California Coastal Ocean Observing System