Metadata education suggestions and materials for:
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Overview of the Metadata Content Standard |
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"Using a standard to create metadata enables the GIS community to speak in like terms. It also sets the basis for software development by standardizing items and item descriptions. This has enabled the development of cataloging and indexing tools as well as search engines which can pose queries against collections of metadata." (NC-CGIA)
Some reasons for using a standard: (SDVC)
More reasons for using a standard for metadata (NOAA)
There are many standards and sub-sets or even super-sets of standards available. The reason for so many standards is that metadata is used for different things. At its simplest, metadata is just a bibliographic record used for searching and locating data. Another use of metadata is as a management record. This requires more information about the dataset such as when it was last modified, what changes have been to it, what restrictions are associated with it. The third and most complex use of metadata is designed to actually accompany a dataset, providing critical information on the dataset's development, specifications/structure, and content.
Three very commonly mentioned standards are discussed here: the CDSGM, ISO, and Dublin Core. The CDSGM and ISO standards are "complete" content standards, however they do not require "completeness" and can be used as bibliographic or management record metadata in a simplified form. The Dublin Core is an example of a metadata standard focused specifically for resource discovery. There are probably more metadata standards in this category than any other.
Since 1994, this has been "THE STANDARD" for entering metadata for geospatial data in the United States of America. This standard was developed specifically for geospatial data, though it has been used for non-spatial data as well. In its generic form, it is fairly flexible for entering different types of data, but there are developing "profiles" of this standard which are more appropriate for certain types of data. Working groups have been established to develop special profiles of the CSDGM for cadastral data, wetlands, digital orthoimagery, soils, vegetation, and biological data, to name a few.
Since 1996, the ISO Technical Committee 211 has been drafting an International Metadata Standard. The FGDC has been an active participant in this project and has had a significant impact on the working drafts of the ISO Metadata Standard. Much of the draft ISO Metadata Standard is closely aligned with the CSDGM. To protect the significant already existing metadata investment, it is important to assure that the proposed ISO Metadata Standard allows the maximum compatibility with existing FGDC-CSDGM compliant metadata records. The FGDC is committed to harmonize the CSDGM with the ISO Metadata Standard and has numerous activities ongoing to assure that the harmonization is successful. What this means for GIS data producers/users in the U.S. is that they don't need to wait till the ISO standard is formalized to do metadata; they can go ahead and use the CSDGM, trusting their current work will be compatible to future changes. Please see the Federal Geographic Data Committee website for the most up-to-date information about the ISO standard.
Metadata goes far beyond application to geospatial data. In its broader sense, metadata is intended to facilitate discovery of any electronic resources, of which geospatial data is just one of many types. Dublin Core metadata is specifically intended to support resource discovery. The elements represent a broad, interdisciplinary consensus about the core set of elements that are likely to be widely useful to support resource discovery. Geospatial metadata generated in the federal CSDGM standard, in html format, contains META elements corresponding to the Dublin Core within its header information.
In the previous section, it was noted that there are so many standards because there are so many uses for metadata, such bibliographic searching/discovery; record management; and data use/determining fitness-for-use.
Standards also differ in whether they specify content, format, or use:
A standard must establish a common set of terminology and definitions for concepts related to metadata, including:
In addition, the CSDGM specifies:
Projects involved in implementing metadata have encountered some difficulties associated specifically with the CSDGM, which can be divided into two categories: problems associated with the standard itself, and problems associated with implementation:
Problems specific to the standard:
Problems associated with implementation of the standard:
The first set of problems, specific to the standard, will be fixed as subsequent standards are released (version 1 came out in 1994, version 2 in 1998, version 3 probably in 2000/2001 after the ISO standard has been released) and as additional profiles of the standard are formalized. See What standards are there? in this topic for information on existing and developing profiles.
The second set of problems can be solved by improved implementation strategies of the standard. For the complaint that "the standard is too complex!!" see the topic Issues regarding implementation.
As to the concern that the final product is not easily understandable to the general public or anyone without firm GIS knowledge, it helps to compare the standard to a spreadsheet of rows and columns of numbers. This spreadsheet is full of very useful data; however, the usefulness of the data is not communicated until it is presented in a final format, such as graph or chart or summary table. In the same way, methods of communicating metadata must be implemented. Very few of these communication/visualization methods have yet to be discussed, much less implemented. So far the major topics of interest in the short history of geospatial metadata have been content and format; we're just getting to the point now where presentation and communication is becoming important. One step in this direction is the development in 1998 of a new on-line format for viewing metadata: Peter Schweitzer's Frequently-asked questions format.
Refer to the section How to use metadata
Refer to the following sections in the topic Using and implementing metadata:
Recommended for most geospatial data producers:
Recommended for metadata specialists:
North Carolina Center for Geographic Information and Analysis, "Accessing Data Tutorial" http://cgia.cgia.state.nc.us:80/tutorials/index.html
NOAA Coastal Services Center: Metadata Reference Guide
Berendsen, Margo. "Metadata for the Rest of Us". University of Wyoming Spatial Data and Visualization Center. http://www.wygisc.uwyo.edu/metadata