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The left half of the plot, left of the horizontal dotted line, which indicates the forecast start date, shows the past (see Figure 2a3a). The black dots (connected by black line) indicate the so-called water balance, the proxi observations, which are produced as a LISFLOOD simulation forced with either gridded meteorological observations in EFAS, or ERA5 meteorological reanalysis fields in GloFAS. These black dots show the simulated reality of the river discharge conditions, as close as the simulations can go at the actual periods (average river discharge over months in seasonal and weeks in sub-seasonal).
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The coloured background is the model climatology (see Figure 3b). This climatology is generated using reforecasts over a 20-year period. In the past half Further information on the climatologies and their generation is given here: Placeholder CEMS-flood sub-seasonal forecast generation methodology for the sub-seasonal and Placeholder CEMS-flood seasonal forecast generation methodology for the seasonal. In the past half of the hydrograph, the climatology is always lead time 1, so first week (always as days 1-7) or first month (whichever month of the year it is), as that is the closest equivalent to the proxi-observation-based climatology. While in the forecast half, the climatologies are lead time dependent and for each forecast lead time the equivalent climatology is plotted with that specific lead time.
Probability table section
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