Clark Lake - playa ALSM results

1. Clark Lake - playa ALSM results B4 Project Hudnut & Bevis

2. study area Clark Lake Radio Observatory (T-shape) Clark Lake is flat - it is a dry lake or ‘playa’ surface

3. zoomed-in on study area; playa with a few bushes and tracks

4. scan edge SURFER 0.5 m DEM from NCALM - standard product

5. Two types of ‘corduroy’ artifact type 1 - ‘scan angle artifact’ scanner reads higher going one direction than it does in the other type 2 - scan overlap mismatch aircraft first pass is vertically mis- aligned with second pass

6. Scan artifact - at scan edge on dry lake one sees a pattern of up-down consistently; as mirror flips, height reads differently

7. scan edge This is on a playa surface, so all vertical differences seen here are system noise in the ALSM equipment.

8. scan edge Zooming in on the edge of the overlapped scans, one sees the color difference; blue is low, green high

9. scan edge The inner scan is consistently lower than the outer scan; this is a different source of ‘corduroy,’ the second type.

10. Two types of ‘corduroy’ artifact type 1 - ‘scan angle artifact’ scanner reads higher going one direction than it does in the other type 2 - scan overlap mismatch aircraft first pass is vertically mis- aligned with second pass Second type can be removed by increasing the accuracy of our GPS/INS trajectories