This map is part of a series that are all created using essentially the same method, as outlined in section 2.2 of this paper: Crookston, NL, GE Rehfeldt, GE Dixon, AR Weiskittel. 2010. Addressing climate change in the forest vegetation simulator to assess impacts on landscape forest dynamics. Forest Ecology and Management. 260:1198-1211. The values are species viability scores in the range of 0 to 1, where low numbers indicate that the climate is not consistent with where the species grows and high numbers indicates consistency.