Trends and variability of drought in the extended part of Chhota Nagpur plateau (Singbhum Protocontinent), India applying SPI and SPEI indices

Abstract

Drought is a hydrological extreme and it brings negative consequences over environment, society and livelihood. Globally, drought frequency and magnitude is being amplified due to natural as well as anthropogenic causes. This scientific research attempts to examine the drought severity, trend and consequences applying the SPI and SPEI indices in the extended part of Chhota Nagpur Plateau (India) considering last 25 years period along with 3, 6, 9, and 12 months time scale. Mann-Kendall test and future prediction have also been done to find out the trend of drought. The results show that the frequency and trend of meteorological and ground water drought are being amplified and the years 1999, 2003, 2010, 2015 and 2016 have been recorded as extreme drought. The research revealed that the principal causes of drought are slight change of precipitation, unscientific withdrawal of ground water, modification of cropping patterns and drastic landuse change. District statistical bureau report states that drought events eventually reduce the crop production in most of the blocks of Purulia and severe water crisis creates during post monsoonal months in this particular region. The future prediction result signifies that around 60% mild and 6% severe drought will be faced using SPI index while around 64% mild and 5% severe drought will be occurred considering SPEI index. This scientific study along with integrated watershed management strategies will definitely assist to the regional planners and administrators for sustainable water resource management particularly for semi-arid climatic region of India.