Assessing the Local Uncertainty of Precipitation with Copulas

The traditional geostatistical model requires regional precipitation fulfills assumption of mul-tivariate normal distribution in order to estimate the probability density function(PDF)of any un-gauged location.And the classical statistical model describes precipitation of any ungauged location u-sing only one PDF.The study attempted to use copula-based geostatistical technology to model the un-certainty of monthly precipitation at any ungauged location and compare it with the above two meth-ods.A case study showed that Copula-based geostatistical model could get the PDF of any ungaugedlocation,which not only depended on the density of the observation network,but also on the magni-tude of the measurements and the coverage of cross-validation confidence intervals was better than thatof the ordinary Kriging and ordinary Kriging with Box-Cox transformation.