<Notes>Wet and Dry Analysis for the Cagayan Valley, the Philippines

Abstract

In this first step toward a regional analysis of wet and dry events, the theory of runs is coupled with a multi-site data generation technique in order to serve two purposes. The first one is to define the parameters of the wet and dry events in terms of the runs-characteristics such as the run-length and run-sum, thus placing the wet and dry analysis within the scope of statistical and probabilistic treatment. The multi-site data generation scheme incorporates the inter-dependence (in space and time) between the data at various stations in a region into the analysis. This approach is illustrated by a simulation study using the rainfall data at nine stations in the Cagayan Valley located in the Northern part of Luzon Island of the Philippines. The duration, magnitude and intensity of the wet and dry events are obtained for different demand levels.