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Publishing and Scholarly Communications: Open Access

Types of Open Access Explained

Open Access refers to a set of principles on how scholarly information is disseminated online, free of cost or other barriers, and comes in a number of varieties, often presented in a color-coded naming system. The most familiar and common of these are the Gold, Green, and Hybrid types of open access. 

  • Gold OA: in this model, the publisher makes articles available for free online immediately. Often these have creative commons licenses and require the author to pay fees for publication. 
  • Green OA: sometimes referred to as "self-archiving" green OA where the author posts the article on their own personal site or through an institutional repository.
  • Hybrid OA: is when a journal contains a mixture of open and closed articles. These publishers are funded from two streams; OA article processing charges and subscriptions from libraries. 
  • Diamond/Platinum OA: similar to Gold OA, but the publisher does not charge any article processing/publication fees, nor do they charge subscription fees to readers. 

Determining a Journal's Level of Open Access

Below are a few resources to that can help identify and clarify open access journals and their policies. 

  • Sherpa/Romeo: the site aggregates and analogizes publisher's open access policies and requirements; including self-archiving capapbilities for authors and institutions.
  • Directory of Open Access Journals (DOAJ): a community-curated online directory that indexes and provides access to high quality, open access, peer-reviewed journals.
  • Unpaywall: is an open database of OA articles that offers a free Chrome browser extension and other tools. 
  • Kopernio: similar to Unpaywall, it is an online tool and Chrome browser extension used for locating OA articles/journals. 
  • NCL Guide to Predatory Publishing: created by the Library's public services team, this guide offers information on identifying predatory publishers.

Green vs. Gold OA

What is Plan S?

Plan S, launched in 2018 by the cOAlition-S, is an open-access initiative for science publishing. While primarily adopted in Europe, Plan S looks to make all government funded scientific research available via OA by 2021. 

Creative Commons Licensing

Creative Commons


At this time NOAA does not have any policy dictating the type of CC license authors are to use. As a general rule, the Library recommends making OA publications as open and available as possible; for Creative Commons licenses we would recommend the CCBY level.