Considerable attention is being paid to the principle of openly sharing data to help understandability, verifiability, and reproducibility of results reported in publications. The Executive Order dated May 9, 2013, and the Office of Management and Budget’s (OMB's) Open Data Policy define the policy of the U.S. government regarding open access to information generated and/or funded by government agencies. NASA’s Earth Science Program has been among the first in the world to establish a free and open policy for data and information generated under NASA sponsorship. This policy was established at the beginning of NASA's Earth Observing System (EOS) Program in 1990. One of the purposes of this policy is to promote full and open sharing of data and the effective utilization of information to address basic Earth science questions and provide the basis for developing innovative practical applications to benefit the general public.
In addition to providing free and open access to data, NASA’s Earth Science Program values transparency and reproducibility in scientific research, as do organizations with similar objectives such as the National Science Foundation (NSF), the Earth Science Information Partners (ESIP), the Coalition on Publishing Data in the Earth and Space Sciences (COPDESS), and the Global Earth Observation System of Systems (GEOSS). As such, NASA recognizes the importance of authors using NASA-provided datasets to clearly indicate which datasets were used and provide access to these datasets to readers. While there are several ways of accomplishing this objective, citing datasets unambiguously is among the best.
The practice of referencing or citing datasets is evolving in the community. For example, on March 29, 2012, the National Science Foundation’s Directorate for Geosciences published a “Dear Colleague Letter” on Data Citation, which states many benefits of citing datasets. In January 2012, ESIP’s General Assembly approved “Data Citation Guidelines for Data Providers and Archives.” In December 2013, The American Meteorological Society (AMS) Council adopted a policy statement on “Full and Open Access to Data.” Further elaboration on the AMS policy is provided in the “Data Archiving and Citation” section in its Author’s Guide. In 2014, The Future of Research Communications and e-Scholarship 2011 (FORCE 11) published a Joint Declaration of Data Citation Principles that states in its preamble: “Data citation, like the citation of other evidence and sources, is good research practice and is part of the scholarly ecosystem supporting data reuse.” This joint declaration has been endorsed by 218 individuals and 97 organizations (as of September 2015).
Many publishers have developed similar data policies. Links to these are provided by COPDESS along with a “Statement of Commitment from Earth and Space Science Publishers and Data Facilities,” which notes the “important progress and a continuing commitment by publishers and data facilities to enable open data in the Earth and space sciences.” As of September 2015, there have been 37 signatories to this statement of commitment, including the American Astronomical Society (AAS), the American Geophysical Union (AGU), the Consortium of Universities for the Advancement of Hydrologic Science, Inc. (CUAHSI), Dryad, Elsevier, The Geological Society of London, International Council for Science (ICSU) World Data System (WDS), Wiley, Nature Publishing Group, Science, and Springer.
As a provider of Earth science data to the global user community, NASA’s EOSDIS has a responsibility to enable users of data to comply with these evolving policies regarding the open access to published data and the need to provide data citations. One of the steps EOSDIS is taking is to assign Digital Object Identifiers (DOI’s) for each of the datasets distributed by the EOSDIS Distributed Active Archive Centers (DAACs). Another step is to provide clear instructions to users on how to cite and/or acknowledge the data and services provided by the DAACs. Instructions and links to the DAAC citation policy webpages can be found on the Data Citations and Acknowledgements page on the EOSDIS Earthdata website.
NASA’s EOSDIS will continue to take steps proactively to improve these open data and data citation policies to remain in line with the policies of our community. Our overarching objectives are to ensure that data from NASA’s Earth Science Program can easily be accessed and that research based on NASA-supported datasets clearly cites the sources of these data.