Spatial-temporal Analysis of Droughts over India using Reliability-Resilience-Vulnerability (RRV) index
Abstract
There is an increase in extreme events with the changing climate which brings serious challenges for societies; extremes such as droughts have led to substantial impacts on the livelihood of humans and animals. Drought is one of the most frequently occurring disasters in several regions of India and its assessment is required for effective drought planning and management. This study presented Reliability-Resilience-Vulnerability (RRV) analysis of droughts, which uses the duration and severity properties of drought, estimated using the Standardized Precipitation Index (SPI-3). The study is carried out over India at 0.25˚ resolution using India Meteorological Department (IMD) monthly rainfall data for a period of 121 years (1900-2021). The analysis is carried out for three periods 1900-1940 (1st), 1941-1980 (2nd) and 1981-2021 (3rd). The spatial variation of drought properties duration and severity at 50, 70 and 90 percentile levels elucidate the regions that have higher drought duration and severity. The droughts-prone areas are classified into five categories based on RRV index values (very low: <0.2; low: 0.2 to 0.4; moderate: 0.4.to 0.6; high: 0.6. to 0.8; very high: 0.8 to 1). The RRV combined index maps showed that the period 1941-1980 has fewer drought-prone areas as compared to other periods. Significant shifts are identified in the distribution of spatial extent of drought-prone areas (RRV index map) in India for 2nd and 3rd periods as compared to the 1st period. The drought has increased for the 1981-2021 period, especially for the Indo-Gangetic plain, Jharkhand, and Tamil Nadu. The percentage of areas in India falling in the high to very high droughts category (from RRV index map) has changed over different periods, viz., 42.82%, 33%, and 46% of areas in 1st, 2nd, and 3rd periods respectively. The time series analysis of the percentage area of droughts (calculated by counting the number of grids the SPI value falling below -0.8 divided by the total number of grids in India) showed that there is a substantial increase in the percentage area of droughts in India. The above findings can help government bodies and/or drought mitigation policymakers to understand the areas that require immediate action for drought management, thus to plan a region-specific line of action.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2022
- Bibcode:
- 2022AGUFMGC54C..04G
- Keywords:
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- Severity;
- Resilience;
- Vulnerability