It’s no surprise that as the use of geospatial technology continues to grow, the amount of geospatial data being collected, stored, protected and used increases as well. So, it’s important for organizations to develop good data management practices to ensure the accessibility, reliability and timeliness of their data for users. Geospatial metadata is the best way to keep track of geospatial data assets. When implemented properly, metadata can be an important component of your data management toolbox. Read this blog post to learn about some of the common geospatial metadata formats and tools that you can use to create and maintain geospatial metadata.
For my last blog post for 2019, I’ve selected a topic that is near and dear to all geospatial practitioners—geospatial metadata. I’m sure that most geospatial specialists remember when they used or searched metadata in a project and may have wondered about a metadata file’s construction and use. Geospatial metadata is a very useful, if not essential, aspect of every geospatial data file. The reason for metadata’s importance is that sometimes you need to find geospatial data files and sometimes you just need metadata to remind yourself of what features the file contains and how you made the data file. There are several popular metadata formats that you may see as you search for data around the world. There are some unique formats and several open standard metadata formats.
Like many other things, the ‘devil is in the details’ and metadata is all about the details. So, this means that despite the fact that filling out metadata fields and publishing metadata files look simple, there are some “gotchas” that could trip you up in your metadata project. In this blog post, I’ll provide you with an overview of geospatial metadata and some of the tools that can be used to meet your metadata project requirements.
Let’s start with the common metadata file types (metadata styles) used in Canada. These are:
Item Description – In an ArcGIS system, there is a simple set of basic metadata available in the ArcGIS Catalog or metadata window. Fields included in the item description are: data type, tags, summary, description, credits, use limitations, extent, scale range, topics and keywords, citation, and resource details. This type of metadata is contained within the spatial data files.
The view of an empty Item Description metadata record from ArcGIS Pro.
ISO 19139 Metadata Implementation Specification—This standard-based metadata style allows users to view and edit a complete metadata document that complies with ISO standard 19139, Geographic information — Metadata. An ISO 19139 metadata file is defined by an XML schema and is included as a separate XML file from the spatial data.
North America Profile of ISO 19115 2003—This standard-based metadata style allows users to view and edit a complete metadata document that complies with North American Profile of ISO 19115:2003 – Geographic information – Metadata. A NAP metadata file is defined by an XML schema and is included as a separate XML file from the spatial data.
Harmonized ISO 19115:2003 North American Profile (HNAP) metadata for Government of Canada geospatial data. This metadata format is a Canadian variant of the North America Profile of ISO 19115 2003, which has a defined XML schema that supports federal government requirements. However, HNAP is not fully compatible with either the ISO or the NAP standards and thus requires unique processing.
ArcGIS metadata is an internal format for ArcGIS systems. ArcGIS supports many metadata styles and types such as item description, ISO, NAP and other metadata formats, so metadata in any or all of these styles can all be stored and processed from within ArcGIS metadata format because ArcGIS needs to handle many different metadata styles.
Item Description metadata editing screen from ArcGIS Pro. Users can enter or edit the appropriate information into the metadata fields for the spatial data file they are using.
For handling metadata, both ArcGIS Pro and ArcMap allow users to view and edit metadata in most of the commonly used formats noted above. But just recently, ArcGIS Online began to support standard-based metadata such as ISO 19139, the North American Profile, the US FGDC CSDGM metadata format and the European INSPIRE metadata directive format. ArcGIS Online also now allows users to edit their metadata inline.
A metadata editing screen from ArcGIS Online. Note that tabs are available for data edit and entry of specific sections of the metadata. The editing commands available include: view, validate, download, delete, overwrite, save and close.
Metadata is essential for specifying and documenting the data that is contained in a geospatial dataset. This metadata information can be used for many purposes—from a reminder to the data owner of what is in the dataset, to publication in a public geospatial metadata catalogue. From an SDI perspective, the biggest requirement for comprehensive metadata is that it enables datasets designed for a particular purpose to be found and reused for other purposes. Quality metadata is an essential component of modern geospatial data management systems. So, are you keeping the metadata about your geospatial assets up to date and accessible for others to find and use?