Non-Stationary Weather Extremes and the Resilience of Critical Lifeline Infrastructure Network-of-Networks

Critical lifeline infrastructure networks, such as transportation, power, water/wastewater, and communications, need to be robust to perturbations, as well as gracefully recover from damage, caused by extreme events such as floods or heat waves and severe stresses such as droughts or regional water scarcity. The lifeline networks are interdependent, thus cascading failures may further complicate the challenges. The extreme events or severe stresses can be more intense than the design perturbations, both owing to natural variability and because of change, or a combination of the two. In particular, the statistical attributes of weather and hydrological extremes have been showing signs of change across many regions of the world owing to a combination of issues such as greenhouse-gas emissions induced warming, impacts of aerosols, regional changes in land use or irrigation patterns, and urbanization. These changes in hydrometeorological extremes may alter the fundamental basis of proactive design, as well as advance plans for robustness and recovery. Here we develop geospatial and temporal risk profiles of potential nonstationary hydrometeorological extremes and examine what these could mean for the resilience of lifeline networks and network-of-networks at scales ranging from urban communities to megaregions, or interconnected urbanized areas, as well as larger regions. Strategies are developed for translating the risk profiles to actionable plans for enhancing robustness to shocks and pulses as well as for effectively and efficiently recovering from damage. Case studies which may be examined in the future are discussed.