Development, Assessment and Commercializaton of a Biogeochemical Profiling Float for Calibration and Validation of Ocean Color and Ocean Carbon Studies

The primary goals of this effort are to develop the technology and expertise to measure optical properties of the upper ocean autonomously over long time scales (months to years) and to make those observations easily accessible to researchers and the public. This will allow monitoring of events such as phytoplankton blooms and will aid in our understanding of physical and biogeochemical dynamics of the upper ocean.

This work will also lead to development of alternative (and cheaper) methods to calibrate satellite ocean color observations using sensors that can be easily deployed across a wide geographic range.

Objective

• Manufacture and test five floats that will measure physical and optical quantities in the upper 2000 m of the ocean
• Develop an optical package that communicates with the float and is able to update sampling strategy using commands telemetered from shore
• Develop hardware, software, and variable parameters for customized sampling strategies
• Determine the best sampling strategies to maximize data quality within power, data, and cost constraints
• Field-test to examine robustness of the measurements (compare to satellite observations)
• Develop software to transfer data efficiently to end users
• Develop software to link with NASA remote sensing products that will provide context for float measurements

We have approached this work collaboratively. Several manufacturers are involved in designing, assembling, and integrating instruments and software (WET Labs, Satlantic, Teledyne Webb, CLS America). Some of the instruments are nearly unmodified versions of stock instruments, while others have required substantial modifications to meet the needs of this mission. The data display technology and data products are also being developed collaboratively (CLS America and NASA-Goddard). The technical work is being overseen and coordinated by the University of Maine. All the manufacturers and developers have worked together to meet the needs of the project within the constraints of the instruments being used.

University of Maine will be responsible for data analysis and scientific results. Data quality will be assessed using:

• Stability of deep water values
• Comparison of surface measurements to satellite observations
• Redundancy of measurements–some particle properties can be computed from multiple instruments on the platform, and these quantities can be compared
• Tests at the site of an established ocean optical observatory (e.g. BOUSSOLE)

This project has involved several individuals at each organization, principally:

• UMaine – Emmanuel Boss and Greg Gerbi: coordination and oversight; development of data analysis methods
• CLS America – Bill Woodward, Phillipe Le Normand, and Seth Ornstein: communications and software development
• NASA-Goddard – James Acker: software development and coordination with NASA's GIOVANNI satellite data products
• Satlantic – Marlon Lewis, Keith Brown, and Diego Sorrentino: hardware and software development to integrate optics instruments with each other and with float
• Teledyne/Webb – Dan Webb, Hugh Fargher, Bill Wallace, and Matt DeDonato: hardware and software development to integrate optics instruments with float and to control mission
• WET Labs – Ron Zaneveld, John Koegler, and Andrew Barnard: instrument modification and assembly
• Laboratoire d’Océanographie de Villefranche – Herve Claustre and David Antoine: logistical coordination of field tests and assistance with data comparison to existing buoy observations

In the coming year we will complete assembly of the first two floats and perform field tests in the spring of 2011. Based on the outcomes of the field tests we will evaluate sampling strategies and construct floats three and four with appropriate modifications. We will deploy those floats on ships of opportunity in areas of interesting ocean dynamics and optical processes. Data processing will be a priority in the coming year. This includes data display development and coordination with NASA satellite products will also take place in the coming year. UMaine will work on algorithms to assess heat flux and primary production from the observations.