OPTIMAL SELECTION OF NUMBER AND LOCATION OF RAINFALL GAUGES FOR AREALRAINFALL ESTIMATION USING GEOSTATISTICS AND SIMULATED ANNEALING

This paper presents a method for establishing an optimal network desig n for the estimation of areal averages of rainfall events. The problem consists of minimising an objective function which includes both the accuracy of the areal mean estimation (as expressed by the kriging var iance of estimation) and the economic cost of the data collection. The well known geostatistical variance-reduction method is used in combin ation with simulated annealing as an algorithm of minimisation. This m ethodology has several advantages which will be demonstrated in this p aper. Several synthetic examples are shown in order to illustrate the performance of the methodology in two different optimisation problems: the optimal selection of a subset from a set of stations that already exist and the optimal augmentation of a previously existing network. (C) 1998 Elsevier Science B.V. All rights reserved.