It could be used to provide a platform on which systems developers could base their development efforts, supporting the computing industries involvement in the building of marine information systems.
9.1 Benefits of XML
The use of XML to form a metadata ‘tag’ for marine data will have many benefits for the marine community including:-
･Improving data discovery,
･Automating database population,
･Automating aspects of data quality control and data set integration
･Simplifying data exchange.
･Simplifying the processing of data.
･Provide a common platform to support marine data management system developers
･Supporting the entry of data into analysis and visualisation applications
XML can provide the conduit for the creation of different versions of the data as it transitions from its initial collection, to the management, analysis and display phases. It could also provide the ability to track individual datasets as they become part of integrated databases and part of value added products. This is an important consideration when intellectual property or ownership of data is an issue.
XML can provide the key to linking data to information and also provide linking to analysis, management, exchange and display applications. This is the underlying framework discussed earlier. An added benefit is the ability to easily create new and different ‘views’ of a data set. An obvious example of this is the use of different languages to present the appropriate view of the data depending on the nationality of the user. The ability to ‘internationalise’ the data and also the applications has tremendous commercial value as well as scientific benefit.
9.2 How Would IODE Go About Creating a Marine Version of XML?
IODE has attempted to create data formats in the past and the General Format Three (GF3) is the latest version of this process. Unfortunately, while it is an excellent format, it has not been widely adopted. The main reason for this is that data management and scientific agencies have already invested millions of dollars in developing independent data management systems. The cost of changing these to support GF3 is not seen as outweighing the benefits GF3 would bring. As a result few agencies have adopted this standard.
The problem with formats is that they are generally too prescriptive. Even if they provide a structure that is relatively flexible they still have difficulty handling the wide variety of structures that exist especially when considering physical oceanographic, geophysical, chemical and biological parameters. In addition to this, each user of marine data has software in place to take advantage of their own or their agency's data formats. They do not want to convert either their data or their software to support a new format. There is no incentive and little perceived benefit from doing this.
An XML based solution provides a higher level approach than the use of specified data formats. An XML based approach has fewer negatives associated with it and could be more easily agreed on by the broad community. Experience indicates that agreement on a specific data format between a number of individuals is almost impossible to achieve, but what if we try and agree on how a field within a data record is structured and described.
