Reference
Crimmins, M. A., Ferguson, D. B., Meadow, A. M., & Weiss, J. L.. (2017). Discerning “Flavors” of Drought Using Climate Extremes Indices. Journal of Applied Meteorology and Climatology, 56(4), 989-1001. https://doi.org/10.1175/JAMC-D-16-0270.1