Global AgWet Mask for SSEBop ET Model Version 7

The AgWet (Agriculture Wetland) mask is a specialized land‑cover dataset developed to enhance wet-bulb boundary parameterization in Version 7 of the SSEBop evapotranspiration model (operational Simplified Surface Energy Balance), particularly improving the Forcing and Normalizing Operation (FANO) algorithm over wet-bare surfaces. In sparsely vegetated surfaces, low NDVI (Normalized Difference Vegetation Index) combined with wet soil can violate the FANO assumption of an inverse NDVI–LST (Land Surface Temperature) relationship, leading to underestimated ETa. The AgWet mask addresses this by restricting the wet-bulb parameter to agricultural, rangeland, and wetland areas exhibiting active vegetation (NDVI >= 0.4). The dataset is produced by integrating multiple global and regional land‑cover sources, including HydroSHEDS (Hydrological data and maps based on SHuttle Elevation Derivatives at multiple Scales), GLWD wetlands (Global Lakes and Wetlands Database), European Commission ASAP (Anomaly Hotspots of Agricultural Production) crop and rangeland masks, NLCD (National Land Cover Database for U.S.), and NALCMS (North American Land Change Monitoring System). The maximum extents of relevant land‑cover classes from each source are extracted, converted into binary masks, and merged into a unified raster representing vegetated agricultural and wetland environments. The resulting product provides a consistent, continental-scale land‑cover mask tailored to enable more accurate wet-bulb/cold‑boundary definition and enhance ETa performance in the SSEBop version 7 modeling framework.