Wikipedia:IPCC citation

[Under construction]

Citation of the Intergovernmental Panel on Climate Change (IPCC) Assessment Review reports is challenging, with complications not seen in other sources. Described herein is a system of citation developed to provide clear, consistent, accurate, and easy to use citation of IPCC sources, particularly for the Assessment Reports. Ready-to-use filled-out templates are available for the following:

• Sixth Assessment Review (AR6)
• Fifth Assessment Review (AR5)
• Fourth Assessment Review (AR4)
• Special Reports (SR)

Templates for the First, Second, and Third Assessment Reports (FAR, SAR, and TAR) are not yet ready. Only a limited number will be prepared, as these ARs are considered scientifically obsoleted by subsequent ARs. Where these need to be cited (presumably for historical purposes) it is recommended to follow the form developed for AR4 and AR5. Ask on the Talk page if you need assistance.

Differences between this system and the IPCC's preferred form

The principal difference between the citation format developed here and that requested by the IPCC is: each IPCC full citation – typically of a chapter – includes a complete description of the work containing that source, while the form recommended here replaces that with a link to a full citation for the enclosing work. The IPCC forms are intended for independent, stand-alone use, which makes much duplication when there are multiple citations; the form here eliminates duplication by referencing a separate, single full citation for the enclosing work. Also, while the IPCC prefers to list all authors (and, optionally, all editors at each level of the whole work), this is not useful, as many chapters have around twenty authors, and some have over fifty. The canonical forms provided here include at least the first eight authors (or editors) in the template, but display only the first four. (As set with the |display-authors= parameter.)

The previous recommended form cited chapters by author's last names. Identifying chapters by number (or title) was found to be clearer and easier to use, and avoided complications when chapters have the same lead authors.

Description

The system of IPCC citation developed here uses short-cites created by the {{harvnb}} template to link to a source's full citation. This is not a "parenthetical referencing" system, as the short-cites used here 1) do not require use of parentheses 2) nor inclusion in the text (although those are permitted if an editor so chooses), 3) nor do they use the "author-date" convention of identifying the full citations.

Experience has shown the author-date convention to be unsuitable for IPCC citation. The convention developed here is to use an index string concatenated from a set of key words and the year. All of these index strings begin with "IPCC", to ensure there is no conflict with any non-IPCC sources that by chance might be similar. For the Assessment Reviews (AR) the next term identifies which review: FAR ("First Assessment Review"), SAR, TAR, AR4, AR5, or AR6. The next term specifies which Report: that of Working Group (WG) I, II, or II, or the Synthesis Report (SYR): WG1, WG2, WG3, SYR. Within each Report are various chapters, typically a Summary for Policymakers (SPM), a Technical Summary (TS), some numbered chapters, and one or more Annexes. Thus Box TS.1 ("Treatment of Uncertainty") in the Technical Summary of the Report of Working Group I in the Fifth Assessment Review of the IPCC can be cited to "IPCC AR5 WG1 TS 2013", which links to the proper full citation for that chapter.

A particular challenge in citing IPCC Assessment Reviews is that the citable units (generally the chapters) are contained "in" a work (a Report) that in turn is contained "in" a larger work (the AR). The IPCC recommendation for handling this is to put all of the information for all levels into each citation. While this is acceptable for an isolated, stand-alone citation, in articles with several dozen such full citations this not only entails unnecessary duplication of data, it also obfuscates the information in each particular citation, and makes them harder to work with.

The solution developed here is to replace the information about the next higher level with a link to that level. No information is lost, it simply is not repeated at a lower level.

This system is agnostic on whether citations should be in notes, or in the text (with or without parentheses). While it is recommended that the full citations be collected in a section dedicated for that purpose, that is only for ease of maintenance; functionality is not affected if the full citations are in notes.

"Sources" section

It is strongly recommended that citations of the IPCC Assessment Reports be in their own "Sources" or "IPCC sources" section, even if the article's established citation "style" is to put full citations in the article text. Even with the abbreviated form used here, mixing full citations in the wikitext makes both harder to read and maintain. Experience has shown that full citations are effectively unmaintainable unless they are in a dedicated secton. It also sets off the non-standard (albeit occasionally entertainingly inventive) forms of IPCC citation added in the article text by "drive-by" editors who have not read these recommendations.

Introduction of a "Sources" section (by any name) should not be done arbitrarily. Per WP:CITEVAR, where a consistent style of citation has been established for an article consensus is required to alter that style. In many cases this is not difficult to obtain, especially if someone offers to organize the existing IPCC citations. (Tip: do not ask for permission to proceed; ask if anyone would object to the proposed changes.) If consensus is not obtained there are basically two options. First, put the full citations into notes however is convenient, as the in-line short-cites can find their full citation wherever it is. However, trying to maintain a set of related full citations that are dispersed across an article can be quite excruciating. In that case the second option might be preferable: move on to another article.

See also

• WP:Basic citation concepts. Clarification of essential concepts.