The Internet plays an increasing role in GIS. Be it for publishing maps or for exchanging data. New GIS applications are Internet enabled. The current websites containing geographic information are often dedicated to one subject, while integration of different data sources opens up new possibilities.
My last project at ESRI Nederland consisted of creating a web site where professionals can find statistical water related monitoring data (http://www.waterstat.nl). The developed application allowed for geographical selection and for this purpose a so-called map service was created. In a presentation I gave at our annual user conference in the Netherlands, I used this map service to demonstrate the possibilities of one of the ESRI (http://www.esri.com/) products to use Internet data sources in addition to local data.
During my presentation, I realized that the map service was not created as a data source for a GIS conference. It was dedicated to serving an Internet application. This led me to visit other web sites that serve maps and there one can see a similar phenomenon. Interesting maps are being used within these applications. The available Internet maps could be used in many different projects. But this is certainly not common practice. This is a bit sad. After all, how many of us have convinced our customers that GIS is the means of integrating different data sources!
Internet is widely available to organizations, modern GIS products are able to access data sources over the Internet, and maps can be served through the Internet. These ingredients can be combined into applications that give us access to information from local and national governments, combined with commercial data and data created with a project. Multiorganization projects can use a common dataset where each party contributes by supplying a dataset dedicated to one aspect of the project.
Although technical requirements may have been fulfilled to a large extent, there still are some hurdles to be taken. Currently organizations are used to prepare datasets that are only used by the organization itself. The possibility of others using their data requires not only the willingness to share information. It also requires the notion that a dedicated dataset might be used in a broader perspective than the project the dataset resulted from.
For a dataset to be suitable to be integrated with other datasets, one has to know something about its content, its quality, its purpose and so on. Initiatives such as the Geography Network (http://www.geographynetwork.com) implement metadata standards that allow for the search for that missing peace of data. However, being able to find different dedicated datasets and put them on the same map is only the beginning of integration. Content standardization is just as important.
A good example is the development of a nationwide data standard in the Netherlands, used by water authorities (http://www.idsw.nl/standaarden/model/entiteit_relatie/). The good thing of this standard is that it is a result of an initiative from water authorities themselves. Different competing GIS vendors participate in this standard by building applications and extending the standard with new data models. These vendors are all members of the Open GIS Consortium. This means that both with respect to content and with respect to the technical side of things standards are available and in use. Dutch water authorities are now implementing Intranet applications based on this common data standard and some of them are even publishing their maps on the Internet. The step towards being able to use each other’s data is not a big one.
We will have to dedicate ourselves to integrating data. So be a publisher and give us access to your information. It will help us make better decisions and that is beneficial for you too!
Appeared in GeoInformatics Magazine (www.geoinformatics.com) in November 2001
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