FOREWORD 
Global and mesoscale oceanographic applications 
and coastal-zone studies require ocean-color imagery 
and sea-surface temperature measurements from 
satellite-borne instruments. Measuring and mapping 
chlorophyll concentrations, sediments, and temperature 
are of particular interest. These data provide a meas- 
ure of the spatial and temporal variability of phytoplank- 
ton biomass, sediment concentration, and ocean cur- 
rents. In addition to this research that promises to pro- 
vide an enhanced understanding of basic physical and 
biological processes in the biosphere, these data also 
constitute the basis for many commercial and opera- 
tional applications of significant importance to several 
industries and to the U.S. Navy. 
The first satellite-borne ocean-color sensor was 
the Coastal Zone Color Scanner (CZCS), which was 
aunched aboard the Nimbus-7 satellite in October 
1978 and operated successfully until the summer of 
1986. The purpose of this instrument was to establish 
the feasibility of determining chlorophyll concentrations 
from space by measuring ocean color. A mathematical 
relationship between the CZCS estimates of algal pig- 
ments and in-situ plankton chlorophyll measurements 
was first established in 1980, and validation experi- 
ments are continuing to extend the accuracy and utility 
of this relationship. CZCS data were also found to be 
useful in defining ocean fronts, current patterns, and 
coastal sediment transport. The knowledge of these 
phenomena, in conjunction with sea-surface tempera- 
ture measurements, was clearly shown to have eco- 
nomic significance for fisheries through the NASA Fish- 
eries Demonstration Program. 
These successes led to formation of a Science 
Working Group, chartered by NASA, with members rep- 
resenting the academic oceanographic community, 
Goddard Space Flight Center (GSFC), and other agen- 
cies. The group recommended that NASA build and fly 
an advanced Ocean Color Imager (OCI) to meet re- 
quirements for ocean chlorophyll data. The group's re- 
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