There is a clear requirement for systems that will promote and facilitate the access by individuals, institutions and national entities to relevant global and regional level information. Especially for the land, observations are often scattered and need to be assembled from a large number of sources and locations and may often require substantial analysis to create internally consistent databases. There needs to be explicit links with a variety of different existing data systems. At the heart of any data system is a requirement for high quality meta-data describing data sets, including attributes such as location, time of collection and data reliabilty and quality. Rather than any sort of centralized system, a highly dispersed system is envisaged. Another essential aspect of data and information distribution is to ensure agreement to, and implementation of, data policy that leads to free and open access to the data sets.
To the fullest extent possible, the GCOS/GTOS data and information systems will rely upon existing national and international programmes. Systems operated by these programmes, such as the ICSU World Data Centres, World Weather Watch (WWW) of the WMO, GOOS, UNEP's GRID and many others, should be enhanced as necessary to meet data requirements rather than creating new entities. Tasks necessary to implement the system will be performed by the existing world and national observing systems, telecommunications networks, and data and processing centres. GCOS and GTOS should act to ensure data are collected, validated, processed and archived to the exacting standards necessary. They should also review, monitor and coordinate activities between groups to ensure proper data are being collected and can be exchanged easily.
Figure 3. Relationship between GHOST sample and total possible samples.
Figure 4. Characteristics of the GCOS/GTOS Data Management System.