e. Discussion 



Geometric position accuracy is obviously of much greater 

 concern to the land resources teams than to ice and oceans 

 groups. Greater accuracies are also possible over land 

 due to the ability of ground control points. The 

 compromise figures shown in Table 5, are based on the most 

 stringent requirements stated by Renewable Land Resources 

 and will, therefore, satisfy the requirements of the other 

 teams. It is realized that the optimal figure (15 m) 

 cannot be achieved at even relatively short distances from 

 ground control points. However, in view of the importance 

 of this parameter, the 15-m figure has been inserted as a 

 firm goal to be achieved whenever advances in technology 

 will so permit. 



6. Type of Data 



Requirements for data type stated by applications teams are 

 summarized as follows: 



a. Renewable Land Resources 



The large number of different application requirements to 

 be met will necessitate the provision of a variety of data 

 types with delivery times ranging from a few days to 

 several weeks. Both image and CCT data will be required. 

 It is envisaged that much of the analysis will be 

 performed by computers and therefore, digital data which 

 is radiometrically corrected or in geocoded form will be 

 necessary. 



b. Nonrenewable Land Resources 



The prime concern is provision of data which is 

 geometrically corrected to permit coregi stration with 

 other data. Radiometric correction for variations in 

 image intensity across the swath is also necessary. It is 

 assumed that some image analysis will be performed by 

 computers, but a large number of images will be required 

 for visual analysis. As rapid delivery of products will 

 in most cases not be a restrictive factor, production of 

 precise geometrically and radiometrically corrected 

 digital data should be possible. 



c. Ice 



For operational sea ice applications, rapid turnaround is 

 the predominant factor affecting the type of product that 

 can be provided. As backscatter values from various ice 

 features and/or open water is essential to analysis. 



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