a. Renewable Land Resources 



The Renewable Land Resources Team suggested that a minimum 

 target size required in forestry applications will be a 

 cutover of 0.4 ha. However, forest roads may be only 10 m 

 wide and some agricultural crops may occupy fields no more 

 than 50 m wide. Optimum spatial resolution has been 

 established as 7.5 x 7.5 m, 1 look, or 30 x 30 m, 16 

 looks. Acceptable resolution can be as low as 30 x 7.5 m, 

 1 look, or 30 X 30 m, 4 looks. 



b. Nonrenewable Resources 



Geologists are primarily concerned with the detection and 

 identification of surface features that, by inference, 

 will establish subsurface geology. Surface features may 

 vary greatly in size and shape, and it is therefore 

 difficult to establish a minimum target size. However, as 

 resolution of the system improves more features can be 

 identified. A spatial resolution of 20 x 20 m at 4 looks 

 was selected primarily to match the projected resolution 

 of other satellite sensors that are proposed for launch in 

 the 1990s. A 25 X 25 m at 4 looks is acceptable with 30 x 

 30 m at 4 looks considered marginal. 



c. Ice 



Identifiable and measurable target size and shape varies 

 widely for ice applications. It may be necessary to 

 establish the width variation, on a day to day basis, of a 

 long, very narrow open water lead, estimate the size and 

 extent of ice ridges or merely plot the position and 

 subsequent movement of ice floes that cover an area of 

 several square kilometers. A 25 x 25 m resolution is 

 deemed to be optimal, a low resolution of +.100 m is 

 acceptable for rapid access data, and less than 100 m is 

 considered marginal. 



d. Oceans 



A 25 X 25 m, 1-look resolution has been established as 

 optimal, but this figure is based on theory only. The 

 Oceans Team has had insufficient experience in the 

 analysis of SAR data to establish a firm spatial 

 resolution that will meet their major requirements. 



e. Discussion 



Spatial resolution is difficult to define, as so many 

 factors other than the target size must be taken into 

 consideration, e.g., the geometry of the target, its 



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