Animation that does of a low fly over of El Yunque National Forest, Puerto Rico. The entire animation is split screen showing the 2017 data on top and 2018 on bottom. Notice the dense lush forest canopy in 2017 and how it covers and shades much of the forest floor. However, in 2018, after Maria devastated the forest in late 2017, the tree canopy has been greatly thinned exposing much more of the forest floor.
In September 2017, Hurricane Maria's lashing rain and winds also transformed Puerto Rico's lush tropical rainforest landscape. Research scientist Doug Morton of Goddard was part of the team of NASA researchers who had surveyed Puerto Rico's forests six months before the storm. The team used Goddard’s Lidar, Hyperspectral, and Thermal (G-LiHT) Airborne Imager, a system designed to study the structure and species composition of forests. Shooting 600,000 laser pulses per second, G-LiHT produces a 3D view of the forest structure in high resolution, showing individual trees in high detail from the ground to treetop. In April 2018 (post-Maria) the team went back and surveyed the same tracks as in 2017 (before Maria).
The extensive damage to Puerto Rico's forests had far-reaching effects, Morton said. Fallen trees that no longer stabilize soil on slopes with their roots as well as downed branches can contribute to landslides and debris flows, increased erosion, and poor water quality in streams and rivers where sediments build up.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 126.96.36.199.0