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MEMO 93 <br />Table 1. Estimates of SPDSS Landsat MSS imagery affected by banded and striped imagery. <br />Landsat <br />MSS <br />Frame 1976 <br />Date Percentage of image affected by <br />striping Percentage of image affected by <br />bad scan lines <br />37/32 9/5 0 <1% <br /> 4/22 14% <1% <br /> 7/12 14% 1-5% <br />36/32 8/26 0 5-10% <br /> 9/4 0 <1% <br /> 4/12 0 1-5% <br />35/32 5/27 0 <1% <br /> 8/25 0 1-5% <br /> 4/20 0 1-5% <br /> 6/13 0 <1% <br />34/32 8/6 0 <1% <br /> 9/2 0 <1% <br />35/33 6/14 14% 1-5% <br />~ <br />~3 <br />` ~ ~~. y <br />9 <br />~~ ~ <br />, <br />c <br />t ~h~~ 9 <br />~ ~ W.. <br /> <br /> <br />~.' ^ v <br />P~ - a <br />~ d <br />j/~, ~ r~_ . <br />d ~ k <br />_. ~ ~ ~ + <br />1' <br />M <br />~ <br />¥ <br />~Y ~ ~ R~ <br />~ <br />I <br />W <br />~ <br />s <br /> . <br />_ - <br />~yy <br />ti:.. <br />~~~' ~~•._ RV's - ~ .~~ <br />:1tip~ ~i~. .¢ <br />~a~ <br /> r <br />' <br /> ~ <br />ne <br />j <br />~ . <br />~~~ <br />R ~ <br />~F <br />r ~ <br />{~ b 4 <br />4 <br />R. <br />f~ <br />:.7~ ~~ ~l n~y + <br />#~ <br />I~ <br />~ n - ~ ~~ <br />~ ~ <br />y Ya1 ~:i <br />F .. <br />f~ <br />'~ <br />~ ~ ~~ <br />h j W <br /> ~~ <br /> <br /> <br /> <br />~b~ <br />Figure 3. Example of Landsat MSS striping and bad scan line corrections (a) before ERDAS Imagine <br />corrections applied and (b) after corrections. <br />2.4 Cloud Removal <br />Clouds and cloud shadows can significantly alter classification results for multi-date satellite imagery. In <br />this analysis, when clouds or cloud shadows overlapped irrigated parcels, the clouds were removed from <br />the image using an ERDAS Imagine function to "fill" the cloud or cloud shadow affected area with a <br />value of zero. Imagery containing clouds over non-irrigated parcels was not removed. Irrigated parcels <br />affected by cloudy imagery on one or more dates were handled by a separate classification. Cloudy <br />imagery was removed from the multi-date normalized difference vegetation index (NDVI) layer stack <br />before analysis began for the subset of cloud affected irrigated parcels. Procedures for these subset <br />classifications followed procedures described in Section 4.2 of this memo. <br />Page 6 of 59 tij,Rareradde ~eshn~P~gy, ~os~ <br />