Adaptable and comprehensive vulnerability assessments for water resources systems in a rapidly changing world.

Comprehensive and adaptive approaches to vulnerability assessment are crucial for guiding effective adaptation in global water resources systems. A common approach to quantify vulnerability is through indicators, which capture the 'spirit of vulnerability' while retaining practical ease-of-use benefits. However, a comprehensive meta-analysis of reveals two specific limitations of global indicator-based vulnerability assessments for water resources systems: 1) vulnerability is influenced by complex interactions among multi-domain factors, for which indicator quality and data vary; and 2) vulnerability is dynamic and evolves over time, an aspect overlooked in most approaches. In response to these identified challenges, we propose a new dynamic "build-your-own" approach to vulnerability assessment. Our approach focuses on correcting for the identified gaps and biases in indicators and data to improve assessment comprehensiveness. This approach also incorporates guidance around adapting assessments over time to better reflect vulnerability under changing conditions. The open-source nature of our approach and underlying data can facilitate the development and customization of indicator-based vulnerability assessments for diverse applications, supporting practical and relevant planning for more resilient water resources systems.