ADVANCED DATA MANAGEMENT TECHNIQUES IN CLIMATOLOGY: A GEOSTATISTICAL PERSPECTIVE

The aim of this work is to analyse different characteristics of the hydrological variables on which depends the regional water balance in Andalusia, southern Spain, and so to evaluate the water resources of this region.

The work starts with an analysis of the available meteorological data. A geostatistical methodology is presented which enables us to fill in the missing data in the daily time series of precipitation and minimum and maximum temperature, using a stratified monthly semivariogram.

From these completed series of minimum and maximum temperature, the reference crop evapotranspiration in Andalusia can be calculated, using the Hargreaves method, which is evaluated in 16 complete meteorological stations, comparing its performance with other, more reliable methods. A calibration of the method, for use in Andalusia, is proposed as a function of ratio between the average temperature and the average daily temperature range.

Furtheron, an evaluation is made of the spatio-temporal distribution of the reference crop evapotranspiration, precipitation, available water holding capacity of the soil and, in last instance, the water balance in Andalusia. The geostatistical study is adapted to the specific requirements of each of these variables, it is intended to use secondary information (e.g. elevation and soil maps) that is well related with the primary variable and an evaluation is made of the performance of the different variants of the kriging algorithm.

Finally these results are combined to estimate the water balance in Andalusia at different spatio-temporal scales, using two very simple models and using the Budyko relation (or similar) to obtain the exhaustive secondary information that is required for the spatial estimation of the different components of the water balance.