TR-475 Drought Hazard and Vulnerability Maps for Texas

Authors: D. Rajsekhar, V. P. Singh

Natural disasters like droughts have a huge socio-economic impact on society. Despite being an important component of mitigation, the concept of vulnerability in association with extreme events has not been explored much. This report presents a systematic approach for the assessment of drought hazard and identification of drought vulnerability indicators pertinent to the state of Texas. A novel drought index known as Multivariate Drought Index (MDI) was used to simultaneously quantify multiple physical forms of drought. A composite risk assessment was then carried out by considering both hazard and vulnerability components. The risk, hazard, and vulnerability components were quantified using standardized indices like Drought Hazard Index (DHI), Drought Vulnerability Index (DVI), and Drought Risk Index (DRI). A suitable classification scheme was adopted for these indices to group regions into classes ranging from low to high. Mapping of DHI, DVI, and DRI classes led to the generation of risk, hazard and vulnerability maps for Texas. The report emphasizes the importance of including vulnerability of the study area in the event of drought while drafting planning measures. Ultimately, the study aims at bridging the gaps existing in the current drought research, which even though substantial, still fails to address some of the issues, and for developing a comprehensive framework for better understanding of droughts in Texas which will help decision makers to formulate a more effective adaptation and mitigation strategy in future.