Hurricane Maria transformed the lush rainforests of Puerto Rico leaving lots of openings in the forest canopy. NASA scientists studied the island's forests before and after the storm. Goddard's Lidar, Hyperspectral, and Thermal Imager (G-LiHT) is a portable instrument that maps forest health and structure from a small airplane resulting in detailed 3-D views of the forest. G-LiHT sends out 600,000 laser pulses every second mapping leaves and branches, rocks and streams. Almost 60% of the canopy trees lost branches, snapped in half, or were uprooted. Trees with wide, spreading crowns were reduced to a slender main trunk. Forests in Puerto Rico are now one-third shorter on average, after Hurricane Maria. The disturbances affected the whole ecosystem, from soils and streams to birds and frogs. G-LiHT data will help scientists understand how forests and wildlife respond to future changes.
In September 2017, Hurricane Maria struck Puerto Rico head-on as a Category 4 storm with winds topping 155 miles per hour. The storm damaged homes, flooded towns, devastated the island's forests and caused the longest electricity black-out in U.S. history.
Hurricane Maria's lashing rain and winds 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 with Goddard’s Lidar, Hyperspectral, and Thermal (G-LiHT) Airborne Imager, a system designed to study the structure and species composition of Puerto Rican forests. Shooting 600,000 laser pulses per second, G-LiHT produces a 3D view of the forest structure in high resolution. In April 2018, post-Maria, they went back and surveyed the same tracks as in 2017.
Comparing the before and after data, the team found that 40 to 60 percent of the tall trees that formed the canopy of the forest either lost large branches, were snapped in half or were uprooted by strong winds.
"Maria gave the island's forests a haircut," said Morton. "The island lost so many large trees that forests were shortened by one-third. We basically saw 60 years' worth of what we would consider natural treefall disturbances happen in one day."
This version was shown at the Association for Computing Machinery (ACM) / Special Interest Group on GRAPHics (SIGGRAPH) Computer Animation Festival (CAF) on July 29, 2019 at the Microsoft Theater in Los Angeles, CA. It will then be part of the ACM/SIGGRAPH CAF traveling show after that.
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 22.214.171.124.0