Figure 3: Cal/Val Methodologies.

The nadir-viewing spaceborne and airborne lidars spatially averaged aerosol backscatter profiles in the same sheet of the atmosphere with a time offset of no more than 45 min. The zenith-viewing ground lidars time-averaged profiles at one location, offset by as much as 100 km from the CALIPSO ground track. The arrows represent individual laser pulses and lidar viewing directions. Distances are not to scale. (Source of the sattelite image in the figure: NASA A-Train figure13).