Foreseeing drought-prone regions in India under climate change: a comprehensive analysis through the development of Drought Prone Index.

Droughts are one of the most severe natural hazards, and its occurrences are increasingly exacerbated due to climate change. While numerous studies have analyzed drought occurrences using multi-model ensembles (MME) developed considering uniform weights to general circulation models (GCMs), biases inherent in these models impeded the attainment of reliable predictions. Also, studies conducted were region specific and were limited to considering a specific socio-economic pathway (SSP). The inconsistency in findings drawn across different SSPs limits the applicability of these results to implement best management practices to combat drought effectively. In this study, Drought Prone Index (DPI) built on the mathematical framework of Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) has been proposed. This index represents the frequency and severity of the possible drought events considering near future (2024-2060) and far future (2061-2100). Further, to overcome the limitation of bias, a multi-criteria decision-making (MCDM) framework integrating CRiteria Importance Through Intercriteria Correlation (CRITIC) and analytical hierarchy process (AHP) methods has been proposed to create differential weighted multi-model ensemble. The proposed framework is demonstrated considering India as study area. Findings of our study indicate a significant increase in rainfall and temperature ranging between 100-440 mm, and 0.75-3.5 °C across different SSP scenarios. Alongside a decline in rainfall in certain regions of Northeast India and the Western Ghats is observed from the derived spatial maps created using the data of developed MME. Spatial variation of DPI computed at a district level indicates that though the frequency of drought occurrences in the near and far future periods does not substantially increase, the severity of droughts is found to be intense. Findings highlight that it is imperative to consider the influence of climate change while assessing the droughts. These findings can assist policymakers and stakeholders in prioritizing resource allocation and implementing targeted mitigation strategies.