Compound and Cascading Climate Extremes in Chile

Most research and practical risk studies have so far focused on estimating the frequency of occurrence of individual extreme events. Hence, there is an urgent need to better understand the likelihood and impacts of compound and cascading events in Chile as well as unveil physical mechanisms driving such events. This need is more pronounced considering that a significant fraction of the Chilean critical infrastructure (bridges, power plants, water reservoirs, etc.) has not been designed to account for the effects of cascading and compound events. This proposal, involving an interdisciplinary team of researchers (climatologists, meteorologists, hydrologists, glaciologists, and oceanographers), has been designed to respond to this need.

We will focus on a number of costly and deadly hazards that, according to the available information, point to an increase in the risk of compound events (concurrent hazards) and cascading events (consecutive hazards) in Chile: HWs, droughts, wildfires, ARs, algal blooms and GLOFs.

Our mission is to assess the severity and frequency of compound and cascading events in Chile. Rather than applying the traditional risk assessment methods (that typically only consider one driver and/or hazard at a time), we will investigate spatial-temporal patterns of concurrent hazards (for example, HWs-fires-droughts) and consecutive hazards (for example, HWs-> droughts-> fires and ARs -> flooding -> algal blooms). We will combine existing datasets of individual hazard identification with regional climate models and climate observations to identify hotspots of compound effects and associated trends, and to determine the main drivers. Moreover, by using Regional Climate Models (RCMs) and assuming an array of emission scenarios, we will also assess the expected increase by mid-century in the number/severity of compound and cascading events, as well as unveil physical mechanisms responsible for these increases.

This project is funded by the ANID Anillo program ACT210046.