Estimation of extreme flow quantiles and quantile uncertainty for ungauged catchments

摘要

Pooled frequency analysis is used to estimate extreme event quantiles at catchments where the data record is either short or not available. This can be accomplished by combining (pooling) information from hydrologically similar sites to increase the available information for estimating the required extreme event quantiles. This paper compares methods for estimating extreme event quantiles at ungauged catchments and determines the uncertainty associated with the estimated extreme event quantiles. The techniques are demonstrated and evaluated using data from a collection of catchments in the Canadian province of Ontario A geographic nearest neighbour index flood-based approach resulted in the lowest mean squared error value.