Long Term Preservation of Earth Observation Data in Europe – Challenge and Cooperation Activities

Earth observation data are unique snapshots of the Earth and the atmosphere. As such they constitute a humankind asset in their importance for monitoring changes in global environmental conditions. With spaceborne Earth observation (EO) missions dating back to the 1970s, 40 years worth of observations are now available in EO data archives worldwide. Data holdings are growing exponentially, e.g. with the Sentinel series of high resolution EO satellites of the European Copernicus Program – which introduces a new dimension of data volumes to be handled.

As other EO data holders around the globe, the European Space Agency (ESA) and its member states are committed to keeping the valuable EO data assets safe, accessible, and useable for an unlimited timespan. Rapidly evolving information technology and changing user requirements call for a dedicated and coordinated approach to EO data long term preservation.

In Europe collaborative EO data stewardship activities are coordinated by ESA within the ESA long term data preservation (LTDP) program. With a view to the entire data set life cycle of historic and current missions an active LTDP working group addresses a wide range of relevant technical and organizational topics. Studies investigate archiving and access technologies, user expectations, or applicable standards; guidelines and best practices recommend preservation workflows, steps to take in curating individual data sets, the composition of the preserved data set, or concepts for introducing persistent identifiers. Fostering an active international exchange, the activities and documents developed within this European LTDP framework extend beyond Europe by being introduced to the Group on Earth Observations (GEO) and the Committee on Earth Observation Satellites (CEOS).

The paper describes the European LTDP cooperation framework, discusses individual focus areas and current activities, and highlights the interaction with global data stewardship initiatives.