In September 2017, South Florida was affected by Hurricane Irma. Hurricane Irma caused large amounts of damage across South Florida, including damage to a large swath of mangrove forests. A combination of hurricane-strength winds and high storm surge across the area resulted in defoliation, broken branches, and downed trees changing the forest structure. Evaluating changes in mangrove forests’ structure and recovery is necessary as loss or change in mangrove forests can lead to a loss in the ecosystems services they provide. This study quantifies changes to mangrove forests caused by Hurricane Irma and their recovery over time. New generation technologies from NASA Goddard’s Lidar, Hyperspectral, and Thermal imager (G-LiHT) provided a unique opportunity to investigate changes in mangrove forests to assess mangrove forests at different tree structures levels. High-resolution airborne imagery collected by G-LiHT before and after Hurricane Irma was used to estimates volumes of damage induced to a swath of mangrove forests and Multispectral satellite data provided an opportunity to monitor and assess mangrove phenology changes overtime. Normalized Difference Vegetation Index (NDVI) calculated from multiple multispectral remote sensing instruments was specifically used to observe and model the change and recovery of mangrove canopy in the Everglades over time.
Using in-field data collected a few months after Hurricane Irma and using changes in processed G-LiHT data we were able to model necromass ( biomass from standing dead trees) for two swaths of mangrove forests. It is seen that lower latitude mangroves were more damaged than their more northern counterparts and that this damage in mangrove forests increased as you moved from the edge of the forest into the interior. We are also seeing a trend of recovery from mangroves within our study area using NDVI time series showing a positive outlook for recovery but this is not true for all mangroves within the Everglades National Park.