Date of Award

Spring 2012

Project Type


Program or Major

Earth Sciences: Oceanography

Degree Name

Master of Science

First Advisor

Joseph E Salisbury

Second Advisor

Janet W Campbell


In an attempt to explore the feasibility of using chromophoric dissolved organic matter (CDOM) as a freshwater tracer in the Kennebec Estuary of Maine, potential causes of the variability of the CDOM absorption coefficient (ag412) in relation to salinity were investigated. A predictable relationship between CDOM variability and factors such as river discharge and season was sought to explain CDOM variability for use in remote sensing. To accomplish these objectives, ag412 was calibrated to continuous underway FDOM measurements using linear regressions from 14 cruises. USGS daily discharge rates were checked for possible relationships with ag412 values. Although no trends were noted, there were elevated CDOM accumulation levels during summer suggestive of summer salt marsh growth. A residence time hypothesis is described to explain the relationship between discharge rates and CDOM accumulation levels in the estuary. The absence of trending in the data suggests that CDOM variability is complex and influenced by multiple factors.