Mapping storm spatial profiles for flood impact assessments

Synthetic design storms are often used to plan new drainage systems or assess flood impacts on infrastructure. To simulate extreme rainfall events under climate change, can be modified match a different return frequency of as well temporal distribution intensities. However, the same magnitude change intensities is applied in space. Several hydrological applications limited by this. Climate urban pluvial floods, for example, require use 2D (rainfall fields) at sub-kilometer and sub-hourly scales. Recent kilometer scale models, also known convection-permitting models (CPM), provide outputs high spatial resolution, although simulations still restricted number scenarios time periods. We nevertheless explored potential data obtained from these impact studies introducing method quantile mapping (SQM). demonstrate methodology, we extracted high-resolution CPM four domains representing areas Switzerland. Extreme that plausible present conditions were simulated with stochastic model. Based CPM-informed stochastically generated fields, fit future scenario using three methods: SQM, uniform mapping, adjustment based rainfall–temperature relationship. Throughout all storms, was same. Using model, assessed methods flooding. Significant differences found water depths between methods. In general, SQM results higher than otherwise. The suggest storm profiles may need re-adjusted when assessing impacts.