Drought indicators-based integrated assessment of drought vulnerability: a case study of Bundelkhand droughts in central India

摘要

Decision makers face multifaceted challenge in characterizing drought climatology for appropriate water resources-related drought management strategies. This paper focuses on understanding and quantifying the drought vulnerability of Bearma basin in the Bundelkhand region of central India, which is one of the prominent climate extremes that the region is affected by frequently. Regular drought conditions have been prevailing in the region in the last decade with continuous drought from 2004 to 2007. An integrated approach using multiple indicators has been developed to spatially identify the vulnerable regions. The Bearma basin has been selected as a pilot basin to develop a methodology for integrated drought vulnerability assessment adopting spatially and temporally varying drought characteristics represented by drought indicators. The temporally varying indicators include standardized precipitation index (SPI), surface water drought index and groundwater drought index. The spatial information of the indicators was categorized in layers prepared in the spatial domain using a geographic information system, and integrated values of weights of various indicators have been computed on a 50 x 50 m grid scale. The SPI has been applied to quantify monthly precipitation deficit anomalies on multiple time scales (1, 3, 6 and 12 months). The drought characteristics including frequency, duration and intensity and magnitude have been calculated with the estimated SPI. The multiple indicator approach has been used for arriving at the drought vulnerable zones. The highly vulnerable areas are located in the southern and northern regions of the Bearma basin. It has been observed that more than 26 % of the basin lies in the highly and critically vulnerable classes and consequently has greater drought-related negative impacts. Results show that the proposed method is highly effective in representing assessments of drought vulnerability.