Comparison of SPI and SPEI indices for drought assessment in eastern part of Satara district of Maharashtra, India

Abstract

Drought indices are normally used as a tool to assess drought conditions. In the proposed study, we have assessed meteorological drought conditions using the Standardized Precipitation Index (SPI) and Standardized Precipitation Evapotranspiration Index (SPEI)for the eastern part of the Satara district of Maharashtra, India. For this investigation, precipitation and temperature data have been used from the period of 1979 to 2014 for sixteen meteorological stations. The same data was collected from the Climate Forecast System Reanalysis (CFSR) website.The result reveals that, according to SPI, severe dry conditions are more prominently observed at stations 2, 3, 8, 9, 11 and 12. Moderate dry conditions are observed at stations 1, 4 and 7. The SPI reveals that notable severe drought events were found in the years 1983 to 1988, 1992, 2000 to 2004, 2007, 2008, 2012 and 2013. According to SPEI, every station has experienced a dry and wet period. Extreme dry conditions are notably observed at stations 2, 3, 5, 6, 8, 9, 11, 12, 15 and 16. Moderate dry conditions are prominently observed at stations 1, 4 and 7. The SPEI reveals that notable extreme drought events were found in the years 1985 to 1990, 1993, 2000 to 2007, 2009, 2013 and 2014. The correlation analysis revealed that there is a strong linear relationship between the SPI and SPEI values.