Integrating conceptual risk models with an adaptation pathways approach to assess and manage systemic drought risks across sectors and boarders

To tackle systemic drought risks, both short-term and long-term decision making that anticipates climate change and balances the varying needs and availability of water across different sectors is required. Adaptation pathways are a promising approach which can enable this, by indicating how to implement adaptation options progressively depending on how drought risks emerge under different hydrological and societal conditions. However, for adaptation pathways to be effective for managing systemic drought risks, they need to take into consideration cross-sectoral and cross-border effects, and therefore be informed by risk assessments that identify vulnerabilities and underlying risk drivers across multiple sectors. In this presentation we showcase research from the recently published World Drought Atlas, demonstrating how conceptual models of drought risks can integrate with a pathways approach to manage shared impacts and drivers of drought risks across different sectors.

Individual Drought Impact Chains derived from literature were developed for five impacted systems at the global level (water supply, agriculture, hydropower, inland navigation and ecosystems). These were brought together to create a systemic conceptual model that identified cross-sectoral and cross-border impacts and shared underlying drivers and root causes of drought risks across systems. We then showed how different risk management and adaptation measures, which are often designed for a single system, can have positive effects across different, interconnected systems by tackling these shared risk drivers and root causes. The chosen measures covered diverse sectoral needs, focusing on water resource management, land-use management and governance aspects, and included grey infrastructure, early warning systems, Nature-based Solutions and community-based approaches. Finally, the measures were brought together in a pathways approach, demonstrating how different clusters of measures, when implemented progressively and in consideration of one another, can strengthen co-benefits and create synergies across systems. The pathways show how combing measures can be more effective against increasing levels of risk, and also when measures cease to be effective and a shift to a new pathway is needed. The pathways framework additionally supports the timing of when measures should be considered for implementation, avoiding less desirable adaptation decisions until absolutely necessary.

While this methodology was developed in the context of managing systemic and cross-border drought risks, the measures and pathways also have high relevance for flood management. This signals that such an approach cold equally be developed for systemic flood risks, or for managing hydrological extremes from both floods and droughts. By integrating adaptation pathways with a cross-sectoral conceptual model of risks, dynamic adaptation planning is supported that connects the vulnerabilities of multiple systems with prospective, forward looking risk management. This helps to reduce uncertainty and manage trade-offs in decision making. Such an approach shows the benefits of taking a systemic lens towards the management of drought risks.