Widespread mangrove damage resulting from the 2017 Atlantic mega hurricane season

Abstract

Comprised of 17 named tropical storms, 6 of which were major hurricanes, the 2017 Atlantic hurricane season ranked as one of the most damaging and costly hurricane seasons on record. In addition to socio-economic impacts, many previous studies have shown that important coastal ecosystems like mangroves are shaped by severe storms. However, little is known about how the cumulative effects of storms over entire hurricane seasons affect mangroves across large regions. We used satellite imagery from the entire Caribbean and Gulf of Mexico region to show that 2017 resulted in disproportionate mangrove damage compared to baseline responses over the previous 8 years. Specifically, we observed 30 times more mangrove damage, via a reduction in the normalized difference vegetation index (NDVI), during 2017 compared to any of the eight previous hurricane seasons, and most (72%) of this damage persisted throughout the 7 month post-hurricane season period as indicated by no NDVI recovery. Furthermore, wind speed, rainfall, and canopy height data showed that mangrove damage primarily resulted from high maximum wind speeds, but flooding (cumulative rainfall), previous storm history, and mangrove structure (canopy height) were also important predictors of damage. While mangroves are known to be resilient to hurricane impacts, our results suggest that increasingly frequent mega-hurricane seasons in the Caribbean region will dramatically alter mangrove disturbance dynamics.

Global declines in human‐driven mangrove loss

“…Storms can have a significant effect on mangrove loss, both through ER and dieback (e.g., EWE; Cahoon et al., 2003; Radabaugh et al., 2019; Taillie et al., 2020). The decline in natural mangrove loss may be associated with a relatively low tropical cyclone landfall period from 2009 to 2016 and a lower accumulated cyclone energy, particularly for the Caribbean (Taillie et al., 2020). The intensity and frequency of tropical storms has increased (Bhatia et al., 2018; Sobel et al., 2016), thus monitoring the frequency and location of landfall necessitates further study to identify future trends in EWE.…”

“…Storms can have a significant effect on mangrove loss, both through ER and dieback (e.g., EWE; Cahoon et al., 2003; Radabaugh et al., 2019; Taillie et al., 2020). The decline in natural mangrove loss may be associated with a relatively low tropical cyclone landfall period from 2009 to 2016 and a lower accumulated cyclone energy, particularly for the Caribbean (Taillie et al., 2020).…”

“…Similarly, we overcome the water masking issues with the GFC loss layer (Lagomasino et al., 2019) to better capture ER along the seaward margin and other flooding conditions. The GFC dataset also captures considerable temporary loss in regions that could recover quickly after cyclones and other EWE (Taillie et al., 2020). Differences in methodology, classification types, and time period make a direct comparison difficult (Table S1), but ultimately the data presented here support previous findings on the dominance of commodity‐driven loss in Southeast Asia.…”

Natural Processes and Human Actuations: Impacts on Mangrove Forests of South America

“…En los meses posteriores al paso del huracán se observó una recuperación del manglar en la mayoría de los lugares estudiados, observándose una recuperación mucho menor o nula en aquellos sitios afectados por actividades antrópicas evidenciando así como la degradación inducida por el hombre construye un factor que influye directamente en la recuperación del manglar (Walcker et al, 2019). Taillie et al (2020), estudiaron, mediante el uso de imágenes satelitales, los daños sufridos por los bosques de manglar en la región del Caribe y del Golfo de México durante la temporada de mega huracanes del Atlántico del año 2017. Los autores reportaron que los manglares sufrieron 30 veces más daños durante el 2017 que en cualquiera de las 8 temporadas de huracanes anteriores, y la mayor parte de los daños persistieron durante los 7 meses posteriores a la temporada de huracanes.…”

Mapping the Extent of Mangrove Ecosystem Degradation by Integrating an Ecological Conceptual Model with Satellite Data

“…By leveraging the vast amounts of information available from satellite data, a range of analyses to investigate different aspects of ecosystem degradation are possible. Examples include: (i) time-series of single satellite-derived indices, such as the normalised difference vegetation index (NDVI) to identify changes in primary productivity [16,22]; (ii) temporal summaries of metrics to model changes in the physical structure of ecosystems [23]; (iii) quantitative modelling of satellite spectral bands [24]; (iv) generalised linear models to estimate ecosystem degradation [25]; and (v) combination of threat maps with satellite-derived maps to identify disturbed ecosystems [26].…”