Pacific Atoll Vegetation Maps

Vegetation classification maps of 235 Pacific atolls (1,925.6 km2 in
total) featuring four land cover classes (broadleaf tree canopy, coconut
palm canopy, low vegetation, and non-vegetated surface) at 2 m resolution.
Coconut palms are mapped with a balanced accuracy of 85.3%, producer’s
accuracy (sensitivity or recall) of 82.5%, user’s accuracy (positive
predictive value) of 68.7%, and specificity of 88.1%. Balanced accuracies
for broadleaf tree canopy and low vegetation were lower (75.5% and 70.3%,
respectively), in part because these classes often appear similar in
satellite imagery. Non-vegetated land was classified with a balanced
accuracy of 87.7%. The 235 classification maps feature an overall accuracy
of 71.1%, significantly higher than the no-information rate of 34.4% (p =
2.2e−16). Across the 235 mapped atolls, 36.6±1.0% of vegetated surfaces
featured a coconut palm canopy. By area, 58.3±1.8% of tree canopies (i.e.
excluding low-statured vegetation) were coconut palm. A patch classifier
identified 310.9 km2 of dense, monodominant coconut stands across the 235
mapped atolls, representing 51.2% of the study-wide coconut
area. The classification maps are provided as georeferenced
GeoTIFF files as well as PDF files for ease of viewing. Tabular databases
including per-atoll and per-islet land cover data are also included, along
with geopolitical and historical data about each atoll.