Reefs at Risk Revisited is a high-resolution update of the original global analysis, Reefs at Risk: A Map-Based Indicator of Threats to the World’s Coral Reefs. Reefs at Risk Revisited uses a global map of coral reefs at 500-m resolution, which is 64 times more detailed than the 4-km resolution map used in the 1998 analysis, and benefits from improvements in many global data sets used to evaluate threats to reefs (most threat data are at 1 km resolution, which is 16 times more detailed than those used in the 1998 analysis).
This dataset the extent of coral reefs around Pohnpei. The data layer shown here is a subset of Pohnpei base layer. The original data, so-called Digital Line Graphs (DLSs), were created by U.S. Geological Survey (USGS) for the 1:25,000-scale topographic maps (2001). The shoreline was modified by by University of Guam (UOG) (2017) based on 2016 Worldview-3 satellite imagery from Digital Globe. The dataset was slightly shifted and also updated (mainly around Kolonia and its vicinity).