SS3.08 Application of Automated Technology to Detect Environmental Change
Date: Thursday, June 13, 2002
Location: Poster Session - VCC
 
MacIntyreHL, University of Maryland, Cambridge, MD, USA, macintyr@hpl.umces.edu
 
MONITORING SHORT-TERM CHANGES IN THE OPTICAL PROPERTIES OF ESTUARINE WATERS WITH IN-WATER SENSORS.
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Satellite remote sensing allows an unprecedented ability to examine the distributions of chlorophyll and physical parameters over wide spatial scales. However, the sampling frequency (usually once per day) does not match the tidal scale of forcing in estuarine systems nor does its reliance on visible radiation allow examination of processes that occur at night. Both can be addressed by in-water sensors that measure the spectral dependence of absorption. The proportion due to phytoplankton can then be estimated with an inverse model that subtracts the contributions of detritus and chromophoric dissolved organic matter (CDOM) using empirically-determined coefficients. The model relies on two assumptions, that changes in the volume scattering function are minor compared to changes in particle loading and that the quantum yield of CDOM fluorescence is invariant. Preliminary testing of the model in the Choptank River, a tributary of Chesapeake Bay, suggests that the approach is robust and that simultaneous monitoring of the physical environment can yield useful information on the dominant forcing factors for (and interactions between) phytoplankton abundance and absorption characteristics, particulate loading and CDOM concentration.