FOREWORD 



As a result of the launch of the Nimbus-7 Coastal Zone Color Scanner (CZCS) 

 in October 1978 and the subsequent progress with data analysis, it is now 

 possible to determine ocean chlorophyll concentrations from space to 

 better than +30 percent for values of 0-5y gS, " in Case I waters (little 



sediment or humic matter). Calculations of annual ocean primary 



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 production vary from 20 to 55 x 10 tons C yr" and may be underestimated 



by three to ten fold, leading to unreliable estimates of world fish 



production and of the role of ocean biota in global C0 ? cycles. With some 



modest improvements in similar satellite instrumentation, together with a 



limited amount of vn_ situ data, it appears feasible to determine global 



marine algal biomass and primary productivity with sufficient accuracy 



that future changes, induced by overfishing or anthropogenic nutrient 



inputs, for example, can be detected. 



With this prospect in mind, the Satellite Ocean Color Science Working Group 

 was established in October 1981 to consider the scientific utility of 

 repeated satellite measurements of ocean color, especially for measuring 

 global ocean chlorophyll and for studying the fate of global primary 

 productivity in the sea. The group was specifically asked: 



a. What are major scientific problems that can be studied using 

 satellite-derived measurements of near-surface ocean color? 



b. To what extent can satellite ocean color measurements make a 

 significant improvement over conventional observations? 



c. To what extent can complementary satellite measurements, such as 

 sea surface temperature and wind speed, or airborne and in situ 

 measurements, significantly augment the value of ocean color 

 measurement? 



d. What are the options on accuracy, resolution, areal coverage, and 

 revisit time of the satellite ocean color observations that best 

 satisfy the data requirements of these scientific problems? 



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