A canonical correlation approach to the determination of homogeneous regions for regional flood estimation of ungauged basins

A canonical correlation method for determining the homogeneous regions used for estimating flood characteristics of ungauged basins is described. The method emphasizes graphical and quantitative analysis of relationships betw een the basin and flood variables before the data of the gauged basins are used for estimating the flood variables of the ungauged basin. The method c an be used for both homogeneous regions, determined a priori by clustering algorithms in the space of the flood-related canonical variables, as well a s for "regions of influence" or "neighbourhoods" centred on the point repre senting the estimated location of the ungauged basin in that space.