G-WADI – UNESCO's Global Network for Waterand Development Information for Arid Lands

  • Howard S. Wheater


Arid and semi-arid regions face immense pressures to deliver and manage freshwater resources. Problems are exacerbated by population growth, expansion of agricultural activities and agricultural/urban pollution. Water stress, over-abstraction of groundwater, salinisation and desertification are common prob lems. However, although the scientific understanding of arid areas is poor, it is developing rapidly, new tools and management information are becoming available and there is extensive experience of water management, both of the application of new scientific and technical knowledge to mitigate against water scarcity and the reapplication of traditional technologies to conserve water. UNESCO has there fore established a global network for the exchange of knowledge and information. Its aims are to promote: improved understanding of the special characteristics of hydrological systems in arid regions
  • awareness of the potential of new technologies for data provision, data assimila tion and system analysis

  • the development and use of appropriate decision support tools for integrated basin management

  • the exchange of management experience, for example through case studies

  • the exchange of data

  • the broad dissemination of understanding of these systems and their integrated management to stakeholders and the general public

This paper reviews the activities and products of the G-WADI programme to date, highlights the need for appropriate modeling tools based on improved science to support integrated catchment management, and identifies the challenges associated with assessment of impacts of land use and land management change on water resource availability and management.


Hydrological systems data and information exchange rainfall charac teristics modeling 


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Copyright information

© UNESCO 2008

Authors and Affiliations

  • Howard S. Wheater
    • 1
  1. 1.Imperial College LondonLondon

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