Citation: Gopar-Merino, L. F., A. Velázquez, and J. Giménez de Azcárate. 2015. Bioclimatic mapping as a new method to assess effects of climatic change. Ecosphere 6(1):13. http://dx.doi.org/10.1890/ES14-00138.1Abstract. Rigorous mapping of climatic patterns outstands as one of the mayor issues concerning climatic change. This paper investigates the extent of the bioclimatic approach to develop a rigorous cartographic methodology to express climatic diversity patterns. Michoacan, Mexico was chosen to represent a region of complex geo-ecological layout where the Nearctic and Neotropical biogeographical realms converge. Bioclimatic indices were computed and their spatial expression was processed in a Geographic Information System. Ground verification was performed at 93 sites across the province. In addition, from 2010 until 2012, more than 2000 kilometers of roads were surveyed to gather data on isobioclimate boundaries. In total, one macrobioclimate, two bioclimates, four thermotypes, five ombrotypes and 14 isobioclimates were distinguished in Michoacan. The Tropical pluviseasonal bioclimate was the predominant bioclimate, covering 56.17% of the province. The Tropical xeric covers 43.82% and the Tropical pluvial is practically negligible, covering 0.01% of the entire province. The relevance of the outcome is discussed in light of its potential use for assessing likely effects of climatic change.