The AI model is more reliable, on average, over all return periods. The AI model has precision over 5-year return period events that is not statistically different to GloFAS over 1-year return period events, and recall that is better than GloFAS over 1-year return period events. Statistical tests are reported in the main text. The boxes show distribution quartiles and whiskers show the full range excluding outliers. The blue dashed line is the median score for GloFAS over 1-year events and is plotted as a reference. Tick labels indicate the sample size (number of gauges) for each boxplot; precision scores (a) and recall scores (b) were calculated over slightly different gauge groups in cases where there are no events of a given magnitude at a given gauge location in either the observations or model predictions causing one score for one model to be undefined. GloFAS and the AI model are always compared over an identical set of gauges in all cases. GloFAS simulation data from the Climate Data Store 33.
