Date of Award

Winter 2009

Project Type


Program or Major

Earth Sciences: Oceanography

Degree Name

Master of Science

First Advisor

Janet W Campbell


With satellite technology, the dynamics of oceanic photosynthesis can be analyzed on a global scale using remotely sensed estimates of chlorophyll concentration. Such work is dependent on the performance of empirical ocean color algorithms that produce the chlorophyll estimates. In hopes to understand the sources of algorithm uncertainty, the NASA bio-Optical Marine Algorithm Data set (NOMAD) was analyzed. The OC4v.4 algorithm estimates were compared to NOMAD's in situ measurements, and a bias was apparent when the data were sorted by ocean (Atlantic, Pacific, and Southern). Several instrumental artifacts were found to be insignificant to the oceanic algorithm bias. Using a subset of NOMAD that contained absorption measurements with each observation, the oceanic bias was independently verified, and explained through differences in the concentration of non-algal organic matter and the phytoplankton community structure. Ultimately, the world's oceans were found to be optically different as a result of differences in biogeochemical processes.