Agricultural and Meteorological Software
agrimetsoft


Skip Navigation Links

Click Below to open List of Question.

What is SPI (Standardized Precipitation Index)?

The SPI is the most popular drought index (Karabulut, 2015) and is a widely recognized index for characterizing meteorological droughts(Hayes et al., 1999; Deo, 2011). McKee et al. (1993, 1995) defined SPI suitable for different timescales (1, 3, 6, 12, 24 and 48 months), and the output values ranged from -2.0 to 2.0. Because precipitation data may be fitted by a gamma distribution, the SPI is calculated as following using a probability density function of the gamma distribution: AgMerra Drought paper

Name: Hidden