North American Grid-Based Sampling Frame: Continental United States at a 50x50km resolution

This sampling frame is a set of grid-based finite-area frames spanning Canada, the United States, and Mexico. The grid for the United States is broken into individual grids for the continental United States, Hawaii, and Puerto Rico. Alaska is combined with Canada into a single grid. Each country/state/territory extent consists of four nested sampling grids at 50x50km, 10x10km, 5x5km, and 1x1km resolutions. The original 10x10km continental United States grid was developed by the Forest Service, U.S. Department of Agriculture for use in the interagency “Bat Grid” monitoring program in the Pacific Northwest and was expanded across Canada, the United States, and Mexico for the North American Bat Monitoring Program (NABat). Additional grids [...]