Southern California Coastal Ocean Observing System (SCCOOS)
Link to NOAA Strategic Plan: NOAA’s Mission Goal 1: Protect, Restore, and Manage the Use of Coastal and Ocean Resources Through an Ecosystem Approach to Management; Goal 2: Understand Climate Variability and Change to Enhance Society’s Ability to Plan and Respond; Goal 3: Serve Society’s Needs for Weather and Water Information
RESEARCH OBJECTIVES AND SPECIFIC PLANS TO ACHIEVE THEM
The Southern California Coastal Ocean Observing System (SCCOOS) is one of eleven regional ocean observing systems that contribute to the coastal component of the Integrated Ocean Observing System (IOOS). SCCOOS is an integrated, multidisciplinary coastal observatory that monitors and integrates ocean and climate observations in the Southern California Bight (SCB) to provide information and assist resource managers in addressing issues in coastal water quality, marine life resources, and coastal hazards. Ocean and coastal observations, data exchange and dissemination, modeling, research and education are designed to meet information needs of data users in the region. The system provides data to users of real-time observations and model-based forecasts using a flexible information distribution system. This is the second of three years that NOAA’s Coastal Observation Technology System (COTS) funding is supporting SCCOOS to deploy, maintain, and evaluate new sensors and information technologies as part of the pilot program to develop and implement the integrated coastal observatory.
SCCOOS is building an operational 24/7 observation system whose components include HF radar surface current mapping, nearshore observations of water quality, subsurface observations (including gliders, AUVs, underway-CTD & moored observations), pier-based observations, satellite imagery, database management in real-time, and a goal of data assimilative ocean modeling in near-real-time. The work described represents the multi-disciplinary and collaborative efforts of the research teams that are contributing to the design and products of the SCCOOS infrastructure.
RESEARCH ACCOMPLISHMENTS
HF Radar
NOAA funding supports two long-range HF radar operated by SCCOOS with delivery of generated data to NDBC. These systems complement the siting and installation of short-range HF radar by SCCOOS through the Coastal Ocean Currents Monitoring Program (COCMP) funded by the State of California. The SCCOOS network has benefited from the leveraging of a project that NOAA NDBC and NOS has with SIO, UCSB, and UCSC for a) developing the data management architecture for a national network of HF radar and b) developing and documenting a quality assurance/quality control algorithms and procedures.
A simulation effort has continued this past year to examine the skill of HF radar to resolve currents of varying complexity. The work has indicated areas of research that would lead to improvement in the retrieval of currents using the technique. The simulations also revealed the importance of tracking the radio frequency SNR of the system for future quality assurance and quality control (QA/QC) algorithms. This will be examined in the future using pre-existing data sets. The results of the simulation activity were submitted to the Journal of Atmospheric and Oceanic Technology to communicate the results to a broader audience of HF radar users.
Also over the past year, QA/QC procedures were evaluated by members of the research team for operational processing of radial current vectors and total surface current vectors. Various parameters computed from standard operational software (e.g. signal-to-noise ratio) were compared with statistical measures of velocity differences between HF radar-derived currents and currents measured by in situ current meters. These parameters were also used in the evaluation of baseline velocity difference, a robust indicator of consistency in radial currents measured by different radar systems. Additionally, several distance-based weighting schemes were evaluated in the estimation of total vectors. Reports summarizing the results of these studies have been submitted to NOAA.
Autonomous Observations
Moorings
The interdisciplinary SCCOOS mooring of the Ocean Physics Laboratory (OPL), UCSB in Santa Barbara Channel has been operational and part of SCCOOS since February 2005. The current deployment period began in May 2007 and the recovery is planned for summer 2008.The SCCOOS mooring provides a crucial link between the two regions and provides data at a depth-resolution rare in California long-term moorings. The Santa Barbara Channel SCCOOS mooring is located in 80 m water depth. It measures currents at every 5 m between 10 and 80 m and temperature at every 5 m between the surface and 25 m and then every 10 m between 25 and 75 m. Additionally, a 13m bio-optical package measures chlorophyll fluorescence, light scattering (turbidity), and photosynthetically available radiation (PAR). Cross-shelf processes are monitored with shallow-water moorings operated by the OPL and other UCSB investigators. High frequency radar arrays measure surface currents throughout the Santa Barbara Channel. Data from the acoustic Doppler current profiler and 13m bio-optical package are transmitted via Iridium satellite link to the OPL website (http://www.opl.ucsb.edu/sccoos/realtime.html). All data are also stored internally and are offloaded upon mooring recovery.
The interdisciplinary SCCOOS UCLA mooring in Santa Monica Bay has been a part of SCCOOS since 2004. The current deployment period started in May 2007 and the recovery is planned for summer 2008. The mooring monitors meteorological parameters and atmospheric CO2. At the sea surface, it measures temperature, salinity, chlorophyll fluorescence, light transmission, dissolved CO2, and currents (4-100 m). The stratification of the upper 90 m is measured with 10 additional temperature and salinity sensors. The water depth is 400m. The mooring measurements are complemented by bi-weekly cruises to the mooring site with measurements of CTD profiles, DIC, alkalinity, nutrients (silicic acid, nitrate, nitrite, phosphate), chlorophyll-a, phytoplankton species (N. Gruber, R. Shipe, UCLA), and trace metals (until 2006, J. Adkins, CalTech). All mooring data, except pCO2, is transmitted with a radio link to land in near-real time and is publicly available at www.smbayobservatory.org. The data is also recorded internally.
The SCCOOS SIO mooring, initially deployed off Pt. La Jolla, was redeployed at a new location off Del Mar in 100m water depth in March 2006. Plans are to exchange to mooring once per year, plus occasional small-boat service visits. The mooring now carries surface meteorological sensors, a downward looking 300kHz ADCP, and surface and 35m seacats with oxygen and chlorophyll fluorescence sensors. All data are telemetered via a radio link. Near-real-time data from the SCCOOS buoy are now streaming to the National Data Buoy Center (NDBC) online archive. Current observations include wind speed, water temperature, and salinity. The data are updated every 20 minutes on the NDBC site, and data are also available on the SCCOOS web site. Data are now available for about 1 year from Pt. La Jolla, and since March 2006 from Del Mar.
Nearshore Observations
Alongcoast nowcasts and forecasts of wave height and alongshore currents driven by waves are provided by the Coastal Data Information Program (www.cdip.ucsd.edu)
Marine Life Resources
Harmful Algal Bloom (HAB) Monitoring Program
Monitoring of HAB species has been conducted from the Oceanside and Scripps Pier in an effort to develop methodologies for a Bight-wide HAB monitoring effort. Analyses for the presence of toxins is conducted when toxin-producing species are identified.
Scripps Pier Chlorophyll Program
The monitoring of chlorophyll, nitrates, and silicates are conducted 3 times a week to develop appropriate methodologies for monitoring large-scale areas to examine the relationship between local biological productivity and nutrient inputs. Understanding these processes is key in understanding what forces algal blooms.
Modeling and Assimilation
The modeling and assimilation teams supported by SCCOOS have recently deployed a quasi-operational ocean circulation model using the regional ocean modeling (ROMS) system. The system assimilates ocean information, including currents measured by HF Radar and subsurface ocean state variables measured by gliders.
Statistical decomposition of the measured surface current fields has been conducted to develop statistical models of ocean response to the forcing variables.
Covariance analysis of surface current data has allowed an objective mapping technique for HF radar derived surface current velocity fields to be developed, in addition to the near-real-time mapping of streamlines and vorticity fields to aid in the identification of coastal eddies.
A high resolution ROMS model run was conducted for fall of 2006 that included the influence of waves on sediment transport in the Huntington Beach region.
Data Management
Data collection and dissemination efforts continue within the SCCOOS program. As the network of HF radar systems grows within California, programmers update and incorporate new data streams into the mapping system. In November 2006, an additional data acquisition computer (Portal) was deployed at Cal Poly, San Luis Obispo. Portal and node systems are currently being prepared for Monterey. Together with the Portals deployed at Scripps Institution of Oceanography, University of California at Santa Barbara and San Francisco State University, these machines acquire data from all HFR systems throughout the state. Data acquisition has been dramatically streamlined, resulting in increased data continuity and scalability as observed by reduced gaps in site records and increased speed of network growth (site additions). The acquisition system has enabled development of online diagnostic utilities providing HFR operators with near-real-time information for monitoring system health. Continuing development at the radial data level focuses on schema development and metadata extraction for further diagnostic information and quality control.
A new objective interpolation approach to mapping all of southern California has been developed and is currently undergoing online beta testing. OI mapping is currently conducted only at the 6km data level. Two side products being generated include maps of stream functions and velocity potential. These products are generated to allow rapid assessment of the presence of eddies in our observational domain—and appear to perform a little better than using vorticity maps, which are sensitive to noise in the velocity measurement.
Near-real-time Level-2 products for Southern California and West Coast, in multiple formats, have been developed including:
• QuikScat – wind vectors
• Jason – sea surface elevation
• Modis sea surface temperature
• Modis color products (chlorophyll, total suspended matter)
• SAR wind speed products – demonstration product, not near-real-time
An interactive web-based mapping system (multiple products, overlays, extract values, animations) has been developed based on MapServer functionality.
Additional SAR/ASTER acquisitions were provided during the Hyperion diversion event to identify surface plume location and extent.
Rolling 7-day near-real-time browse data are being provided for multiple sub-regions including:
• Ocean Color Monitor – chlorophyll, total suspended sediment
• Modis sea surface temperature
• Modis color products (chlorophyll, total suspended matter)
• Optimally interpolated sea surface temperature (GHRSST) – recent addition
SCCOOS has been collaborating with SeaSpace and Remote Sensing Systems.
Fig. 1
Time series of temperature (top) and chlorophyll (bottom).
Fig. 2
Southern California Bight (SBC) ROMS.
