Craig Drennan, Tufts University

Class Year:

2017

Mentor:

Greg Silsbe Ph.D.

Abstract:

Existing ocean color phytoplankton models are not designed to handle the high levels of backscattering and absorbance characteristic to optically complex coastal and estuarine systems, and so are useless in measuring phytoplankton biomass in these environments. An understanding of the behavior of these inherent optical properties is vital in the development of accurate regionally-specific phytoplankton remote sensing models in “Case II” systems like the Chesapeake Bay estuary. This study examined how absorbance and backscattering varied along an “estuarine gradient” in the Chesapeake Bay and one of its freshwater tributaries. We found that both backscattering and absorption decreased from the mouth of the Bay to the headwaters of the freshwater tributary, primarily as a function of depth. In addition, we also made some basic changes to the Quasi-Analytic Algorithm for Optically Deep Waters, an ocean color phytoplankton model designed for use in the open ocean, to improve its performance in the optically complex waters of the Bay.