A NONPARAMETRIC WET DRY SPELL MODEL FOR RESAMPLING DAILY PRECIPITATION/

A nonparametric wet/dry spell model is developed for resampling daily precipitation at a site. The model considers alternating sequences of wet and dry days in a given season of the year. All marginal, joint, a nd conditional probability densities of interest (e.g., dry spell leng th, wet spell length, precipitation amount, and wet spell length given prior to dry spell length) are estimated nonparametrically using at-s ite data and kernel probability density estimators. Procedures for the disaggregation of wet spell precipitation into daily precipitation an d for the generation of synthetic sequences are proffered. An applicat ion of the model for generating synthetic precipitation traces at a si te in Utah is presented.