Evaluation of New Sensors for Emergency Management
21
Leaf on/off and palms
Figure 10 shows site 5 with broadleaf and evergreen trees at 1-ft and 8-in.
GSD. Ground truth was obtained in the form of digital pictures. Broadleaf trees
and evergreens identified in ground-truth photos were located in the imagery on
the median of the roadway (left), but cannot be distinguished visually. In addi-
tion, spectral tests run on broad-leaf and narrow-leaf trees indicated no signifi-
cant differences. Leaf on/leaf off is clearly distinguishable in the upper lefthand
corner of the images near the building where the entire rooftop is clearly visible
(shown by an arrow in Figure 10a) in early February, but it is partly obscured by
the canopy in late March. The distinctive fronds of three palm trees are clearly
visible on the roadway median (right) in the lower righthand corner of the 8-in.
GSD scene (shown by arrows in Figure 10b) but not in the 1-ft GSD scene. Other
palms were also recognizable within the area at 8-in. GSD when present, even
when growing among different species.