Domain decomposition in shallow lake modelling for operational forecasting of flooding

For the prediction of flooding at the borders of the major lakes in the Netherlands, a new system is in operational use. At the moment the time horizon of forecasts is two days ahead. To enlarge this time horizon, the shallow-water models of the lakes will be applied in combination with short-to-medium weather ensemble forecasts up to 15 days. Therefore, in this paper we study how to run ensembles with these models efficiently on current hardware. For this purpose, we use domain decomposition in the shallow-water models to have a good balance between computational times and (parallel) efficiency.