Together with the attached diskette and included software, this publication is a follow-up to an Expert Consultation held in FAO Headquarters in December 1993.

The meeting looked into the “Coordination an Harmonization of Databases and Software for Agroclimatic Applications”. In one of the recommendations, it proposed to “inventory, collect, standardize and disseminate procedures used in agrometeorology, together with guidelines on their use in the solution of agrometeorological and agroclimatic applications”.

The spatial interpolation of agroclimatic data is one of the operations for which standard software is not easily available.

The Unité de Biométrie at the University of Louvain-la-Neuve, Belgium, was therefore requested to prepare the tools, following the philosophy below:

• - the programmes will be provided with a manual giving detailed description of the technique being implemented;
• - the programmes will be distributed both as executable modules and as source code, to allow users to incorporate them into their own applications;
• - the programmes will be made available free of charge and can be freely copied and distributed by users;
• - a set of typical data files will be distributed together with the programmes to allow users to experiment with the programmes.

It is hoped that this manual will be followed by others adopting the same philosophy.

R.G.

• Introduction
  • 1.1 Presentation of the method
  • 1.2 The software
  • 1.3 Installation, file naming conventions and disclaimer
• 2. VARIO module
  • 2.1. Fundamentals
  • 2.2. Estimation of variograms
    • 2.2.1. Stationarity of the mean
    • 2.2.2. Choice of classes
  • 2.3. File structure and syntax
  • 2.4. Example
• 3. COREG module
  • 3.1. Fundamentals
  • 3.2. Fitting the Linear Model of Coregionalisation (LMC)
    • 3.2.1. Type of possible basic models
    • 3.2.2. Choice of the basic models
    • 3.2.3. Fitting the LMC to the estimated variograms
  • 3.3. File structure and syntax
  • 3.4. Example
• 4. COKRIG module
  • 4.1. Fundamentals
  • 4.2. Kriging-Cokriging of values
    • 4.2.1. Size of the neighbourhood
    • 4.2.2. Maximum number of known values
    • 4.2.3. Simplification of a cokriging system
  • 4.3. File structure and syntax
  • 4.4. Example
• 5. A practical case study
• 6. Some references