Mangrove forest digital elevation model for Pohnpei, Federated States of Micronesia, 2019

Surface elevation of the mangrove forest is important for understanding current and future vulnerability to sea-level rise. Due to the lack of LiDAR data and insufficient accuracy of space-borne synthetic aperture radar-derived elevation models, we leveraged data from differential leveling surveys to generate a digital elevation model (DEM) for the mangrove forest of Pohnpei. We created a general slope model with a shore-normal transect of elevation and a general additive model (GAM) spine. To create a continuous DEM, the GAM spline was then stretched across a grid representing the width of mangrove, created using digitized boundaries of the seaward and interior mangrove edge. This simplified approach assumes that the relationship between slope and width of the mangrove forest is constant. This DEM should be considered an intermediate product until a higher quality DEM is made available.