| The objective of this dissertation is to gain a better understanding of the environmental and climatic effects on the temporal and spatial variability of phytoplankton biomass along the West Florida Shelf (WFS). Chapter 1 examines temporal and spatial patterns in chlorophyll concentrations using satellite data collected between 1997 and 2003. Chlorophyll data derived from the SeaWiFS sensor are validated with in-situ data and analyzed. Wind, current, sea surface temperature, river, and rain data are used to better understand the factors responsible for the patterns observed in the satellite data.;My question is whether the standard OC-4 algorithm is adequate for studying short-term variability of chlorophyll concentrations along the WFS. I will examine temporal and spatial trends using the OC-4 and compare them to the Carder semi-analytical algorithm which uses remote sensing reflectances at 412nm, 443nm, 490nm, and 555nm to estimate chlorophyll concentrations separately from CDOM estimates (Carder et al 1999, Hu et al 2003).;In Chapters 2 and 3 the potential problems due to CDOM and bottom reflectance are examined. In Chapter 2 I analyze the influence of riverine-induced CDOM. Water-leaving radiances (nLw) are analyzed in an effort to discriminate true chlorophyll patterns from CDOM-contaminated signals. Chapter 3 examines the impact of bottom reflectance on the satellite signal by using the percentage of remote sensing reflectance at λ=555 (Rrs(555)) to differentiate between optically shallow waters and optically deep waters. Optically shallow waters are defined as those with the percentage of Rrs(555) due to bottom reflectance (%bt_555) ≥ 25%, while optically deep waters have %bt_555 ≤ 25%. These analyses will help assess the validity of the temporal and spatial patterns of chlorophyll concentration observed with the SeaWiFS data described in Chapter 1. |
