As a national organization representing the geospatial community, the American Society for Photogrammetry and Remote Sensing (ASPRS) plays an important role in setting standards for data preservation and archiving. Basic guidelines for managing geospatial data on a daily basis and preventing destruction over time are necessary to maintain accessibility and extend the usefulness of many types of data and derivative products. The ASPRS Data Preservation and Archiving Committee (DPAC) has been working on this topic for the past three years.
John Faundeen, archivist for the U.S. Geological Survey, EROS Center, serves as the chair of DPAC. Members are from private, government and academic entities that are knowledgeable about data preservation and archiving practices and procedures. Their goal is to assess practices and develop guidelines that will be reviewed by the ASPRS Executive Board and then distributed to other ASPRS Committees and the general membership for comments.
There is a wide variety of data types and an even wider array of preservation and archiving issues. “ASPRS wants to make people aware of the complexity associated with this topic,” said Jeff Young, ASPRS Rocky Mountain Region Director, DPAC Member and business development manager at LizardTech. “It is of interest to a broad community. There is no one right answer, but the guidelines that DPAC develops should save organizations from making all the same mistakes, and in the long term result in the effective preservation of data.”
The DPAC recently took on the task of compiling a list of existing international data life cycle models, contributed by U.S. government agencies such as BLM, USGS and NOAA, as well as universities in the U.S. and the UK, and from as far away as the “Make it Digital” initiative led by the National Library of New Zealand. The ASPRS DPAC website includes descriptions of 55 approaches to these models. The next step for DPAC is identifying common practices pulled from the variety of methods, followed by establishing the best practices based on the common practices.
Due to the complexity of the topic, the DPAC committee is functioning through subcommittees that are assigned manageable areas of study. Initial subcommittees include: analog data (aerial photography, astronaut photography, maps, etc.); digital data (spectral image data, GIS, GPS, etc.); Practices and Procedures: Facilities and Holdings; and Outreach.
Data may be important for historical, scientific or legal reasons. There are many questions being considered by DPAC that impact the archiving and preservation guidelines, such as:
1. What are the specifications for a climate-controlled environment to preserve analog or digital data?
2. Should analog original data be discarded or saved along with the derivative products?
3. What media is best for storing satellite imagery to ensure accessibility in the future?
4. Who owns digital data?
5. Who has the rights to use digital data?
6. Is there an extended value from archiving, such as change detection?
7. Who pays for storing, moving and indexing data?
“Many archiving methods today are primitive,” Young said. “We need more research to assess data quality, and determine the best way to manage digital and analog image databases, and possibly recommend what to do with the large volume of data being generated by LiDAR collection.”
The European Union serves as an excellent example of how difficult it is to bring together disparate organizations to agree on a common data concept. Back in 2001, experts from key European Union organizations met to prepare the legislative framework and organization of what became the Infrastructure for Spatial Information in Europe (INSPIRE). With different traditions, cultures and socio-economic models, it is not surprising that the 27 Member States manage and organize their geospatial data with varying quality and standards. It took until 2007 for the mandatory policy to go into effect.
The overarching goals of INSPIRE are to collect data only once and seamlessly combine data into a common database from different sources. Naturally this has not been a painless process. The Member States are aiming for November 2017 to be serving basic data in a compatible format, such as coordinate reference systems, geographical names, addresses and cadastral parcels; by October 2020, more complex data such as elevation and land cover, and energy and mineral resources is scheduled to be available based on INSPIRE’s criteria.
“ASPRS started with the basics, such as defining ‘archive’ and data ‘preservation,’" Young said. “From there, we are working our way through every facet of the issue. The amount of geospatial data being generated will only continue to increase, so we need to have practical, effective methods in place to organize, store and keep data accessible so as not to lose valuable knowledge.”