Marcel Endejan Global Water System Project (GWSP) International Project Office Bonn, Germany CODATA Conference, October 2006, Beijing Assessing the Global Water System: a Holistic View of Key Elements and Datasets Using the Unified Modelling Language

Working definition: … the global suite of water-related human, physical, biological, and biogeochemical components and their interactions. The Global Water System

Richards (1991), WRI (1990) Mackenzie et al (2002)

Working definition: … the global suite of water-related human, physical, biological, and biogeochemical components and their interactions. The Global Water System How are human actions changing the global water system and what are the environmental and socio- economic feedbacks arising from the anthropogenic changes in the global water system?

► Objectives  describe the ► basic elements of the Global Water System ► interlinkages of these elements ► changes in the state of the Global Water System → conceptual framework  provide a consistent set of annotated maps ► Description/interpretation ► related maps  provide data and metadata  support the GWSP Discourse  serve as starting point for a GWS Info Base GWSP Digital Water Atlas

Atlas Website available early 2007 at

UML Class Diagram

Unified Modelling Language ► UML a visual language for specifying, constructing and documenting the artefacts of systems [OMG] ► Different diagrams to represent structure, behaviour, interaction using classes, objects, data types, system states, … ► Class A class describes a set of objects that share the same specifications of features, constraints, and semantic (OMG, 2005) ► Class diagram to represent thinks in a situation of the real world or domain of interest → Domain Model that ‘illustrates noteworthy concepts in a domain’ (Larman, 2004)

List of Important Maps/Datasets ► About 70 topics, including: ► Physical components  Precipitation  River discharge  Dams and reservoirs ► Biological and bio-geochemical components  Biodiversity  Environmental flows  Nutrient loads ► Human component  Gross National Product  Ratification of UN conventions  People’s awareness of biodiversity

Domain Model – Surface Water River discharge Dams/Reservoirs Definitions: ‘Reservoir’: Any natural or artificial holding area used to store, regulate or control water. (World Commission on Dams, 2000) ‘Dam’ A barrier built, usually across a watercourse, for impounding or diverting the flow of water. (North American Lake Management Society, Lake and Water Word Glossary) Draft!

Domain Model – Surface Water Draft for demonstration!

Domain Model water bodies governance land water users Draft!

Domain Model – Dams & Reservoirs Draft for demonstration!

Domain Model – Dams governance operational aspects hydrological aspects physical aspectseconomic aspects Draft for demonstration! Draft!

► GWSP  Human impacts on the GWS  Identification/overview of important elements ► Atlas  system’s view + Maps + description + metadata + data ► Using UML for Domain Modeling  UML is no magic bullet / OO knowledge is needed  Class diagrams easy to understand  Useful to draft, discuss, refine basic elements, linkages, term definitions  Supports the integration of disciplines/datasets Conclusion