2. Geospatial metadata

Geospatial metadata (also geographic metadata, or simply metadata when used in a geographic context) is a type of metadata that is applicable to objects that have an explicit or implicit geographic extent, i.e. are associated with some position on the surface of the globe. 

Metadata documentation has increased attention due to the evolution from Monolithic GIS to Web-GIS. Web-GIS allows spatial data sharing across distributed infrastructure. In this context spatial data documentation has become more important than ever as it allows the users the possibility to find the available spatial data shared by data providers to evaluate where the discovered data fulfill the requirements of their application in terms of scale, accuracy, actuality etc.

The ISO/TC 211 defined metadata by data about the content, quality, condition and other characteristics of spatial data or services and gives answer to the following questions:

  • What spatial data (or service) are available? – Title, short description
  • Who is responsible for data and metadata generation?  - Publisher/Owner
  • Where (geographic location)? – Geographic coordinates (box)
  • Why were the data collected? – Data collection purpose
  • When were the data acquired? – Temporal information
  • How to access the available data? – Data access and lineage

Metadata serve a wide range of applications, apart from data description also the organisation and maintenance of data. Complete metadata descriptions of the structure, contents and accuracy of all datasets is an important requirement for database design.