Oceansat Imagery from the Earth Scan Laboratory

The Louisiana coast receives large volumes of river water from the Mississippi
and Atchafalaya Rivers. The rivers usually flood in spring and sometimes into
summer, producing a stratified water column. The river-borne nutrients fuel
large phytoplankton blooms on the shelf. These physical and biological
processes can result in hypoxia on the shelf, and the "dead zone".

The Ocean Color Monitor (OCM), with 8 spectral bands similar to NASA's SeaWiFS
sensor, is used to estimate chlorophyll a concentrations as well as to quantify
suspended sediments. "True color" enhancements can provide additional
information on cloud cover, water mass color/types, vegetation health, and
bottom type. The fate of river waters and the location of ocean eddies can be
determined using various channels and channel combinations from "ocean color
sensors". One big advantage of the OCM sensor is that its pixels are 360m, in
contrast to SeaWiFS and MODIS which have 1 km pixels.

It is important to clarify that satellite-derived chlorophyll measurements can
be effected by CDOM, suspended sediments, and bottom reflectance. Thus, caution
should be taken when interpreting the patterns in coastal waters.