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The basin Rank-mean and Rank-std values are determined using all the large enough river pixels in the basin. Currently, only pixels above 50km2 are used in EFAS and pixels above 250 km2 are used in GloFAS in the averaging. The basin Rank-mean/Rank-std values are calculated as an arithmetic average of the Rank-mean and Rank-std values of the individual river pixels, weighted by the square of the upstream area, as described below:
Figure 6. Example snapshot of the basin summary maps with the lead time navigation indicated and the categories and basin colours explained.
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