Metadata in GIS is essentially information about data.
Understanding Geospatial Metadata
Think of metadata like the card catalog in a library, but for geographic data. It's a descriptive record that helps users understand the characteristics of a spatial data resource.
As highlighted in the reference, metadata records document the crucial details about a data resource, answering the fundamental questions of:
- Who
- What
- When
- Where
- How
- Why
By providing these details, metadata allows users to determine the content, quality, origin, and other vital aspects of a dataset without needing to open or fully process the data itself.
Key Information Documented in GIS Metadata
Metadata provides a comprehensive description that addresses key questions:
- Who: Identifies the creator, publisher, or contact person for the data.
- What: Describes the subject matter, content, scale, geographic extent, and attributes included in the dataset.
- When: Specifies the date the data was created, published, or last updated.
- Where: Indicates the geographic coverage or area that the data represents.
- How: Explains the methods used to collect, process, and generate the data, including lineage and quality information.
- Why: States the purpose for which the data was created.
Here's a quick summary in a table:
| Aspect | Information Provided by Metadata |
|---|---|
| Who | Data creator, contact person, organization |
| What | Content, topic, attributes, geographic extent |
| When | Creation date, publication date, update date |
| Where | Geographic coverage of the data |
| How | Data collection methods, processing steps, lineage |
| Why | Purpose, application, intended use |
Types of GIS Resources Described
Geospatial metadata is used to describe a wide range of location-based data resources. This includes, as per the reference:
- Maps
- Geographic Information Systems (GIS) files (like shapefiles, geodatabases)
- Imagery (such as satellite photos or aerial pictures)
- Other location-based data resources
Metadata ensures that anyone using these resources can find the necessary information about them.
The Importance of Metadata in GIS
Creating and maintaining good metadata is critical for effective GIS data management and sharing. It enables:
- Discovery: Users can easily search for relevant data based on descriptive keywords or geographic location.
- Evaluation: It helps users assess if a dataset meets their specific requirements for accuracy, timeliness, and content.
- Data Use: It provides instructions, restrictions, and proper attribution details for using the data correctly.
- Organization: It helps data producers manage and track their data inventories.
- Interoperability: Following standards allows different systems and users to understand the data descriptions.
In essence, comprehensive metadata turns raw spatial files into discoverable, understandable, and usable information resources.
