• Tue. Mar 28th, 2023

Visitor put up: What 13,500 citations reveal concerning the IPCC’s local weather science report


Mar 16, 2023

In August 2021, the Intergovernmental Panel on Local weather Change (IPCC) revealed their long-anticipated report on the “bodily science foundation” for local weather change. 

The report concluded that local weather change is “unequivocally” attributable to people and already affecting each area on our planet. These findings had been reported world wide, drawing worldwide consideration.

The mammoth 2,500-page doc brings collectively an infinite quantity of peer-reviewed literature to supply essentially the most up-to-date abstract of local weather science but revealed. Each assertion within the report is backed up by authoritative sources.

Altogether, the report boasts a staggering 13,500 citations.

Our evaluation explores which citations had been included within the report and divulges a surprisingly broad and numerous vary of subjects.

Nonetheless, it additionally exhibits that citations within the report are closely dominated by the worldwide north and generally sit behind a paywall.

We discovered that 99.95% of the cited references had been written in English and three-quarters of all literature cited within the report featured not less than one writer based mostly in both the US or the UK.

When and the place?

The IPCC’s report on local weather science – often called the Working Group I (WG1) report – is the primary part of the three-part sixth evaluation report (AR6). A whole lot of scientists spent years assessing the prevailing literature on local weather change to supply this report, which is able to type the cornerstone of local weather science for the years forward.

The report was adopted by two different instalments on the impacts, adaptation and vulnerabilities of local weather change and the mitigation of local weather change, launched in February and March 2022, respectively. The AR6 will conclude with a synthesis report, launched subsequent week.

The AR6 WG1 report is an replace from the fifth evaluation cycle (AR5) WG1 report, which was revealed in 2013. Authors of the brand new report had been inspired to give attention to offering an replace because the final cycle, explaining the advances in local weather science, how the arrogance of findings had modified or strengthened and what new subjects had emerged since AR5.

We discovered that 98.5% of citations within the AR6 WG1 report had been revealed because the 12 months 2000 and 85% of had been revealed after the discharge of the AR5 in 2013. The chart under exhibits what number of citations had been revealed yearly over 2000-21.

Yr of publication 12 months for all IPCC AR6 WG1 report references revealed between 2000 and 2021. Credit score: Félix Chavelli.

We discovered that 290 (2%) of references are from January 2021, reflecting a push from the scientific group to get papers accepted for publication earlier than the report’s literature closing date on 31 January 2021.

The oldest quotation – “An historic account of the commerce winds, and monsoons, observable within the seas between and close to the Tropics, with an try to assign the bodily explanation for the stated winds” – was revealed by English astronomer and mathematician Edmond Halley in 1686.

We additionally analysed the place the authors of every paper had been based mostly on the time of its publication. In complete, the 13,500 citations have round 39,000 distinctive authors. Nonetheless, many authors co-authored greater than one of many cited papers, and this quantity jumps as much as virtually 130,000 names when these duplicates are counted.

The dominance of the worldwide north among the many quotation authorship is stark. Whereas 185 international locations are represented throughout the citations, we estimate that greater than 80% of authors are based mostly within the world north. The map under illustrates this with a subset of papers revealed between 2011 and 2020. The quantity in every bubble exhibits the variety of authors based mostly in that nation.

Country location of all the co-authors from the papers cited in the WG1 report that were published between 2011 and 2020.Nation location of all of the co-authors from the papers cited within the WG1 report that had been revealed between 2011 and 2020. Map created utilizing SciVal. Credit score: Félix Chavelli

Three-quarters of all literature cited within the report options not less than one writer based mostly in both the US or the UK. Greater than 6,000 of the references embody not less than one writer based mostly within the US. 

Along with the US and UK, Germany, France, China, Australia, Switzerland, Canada, Japan and the Netherlands are additionally represented in additional than 1,000 distinctive references within the report.

The maps under targeted in on the variety of authors from international locations in Africa, Asia-Pacific, Europe, the Center East, North America and South America.

Country location of all the co-authors from the papers cited in the WG1 report that were published between 2011 and 2020. Maps are shown across Africa (top left), North & Central America (top right), Europe (middle left), the Middle-East (middle right) the Asia-Pacific (bottom left) and South America (bottom right).Nation location of all of the co-authors from the papers cited within the WG1 report that had been revealed between 2011 and 2020. Maps are proven throughout Africa (prime left), North & Central America (prime proper), Europe (center left), the Center-East (center proper) the Asia-Pacific (backside left) and South America (backside proper). Maps created utilizing SciVal. Credit score: Félix Chavelli

In many of the maps above, a small variety of particular person international locations dominate every area – for instance South Africa in Africa and Saudi Arabia within the Center East. The one partial exception is Europe – though the UK, France and Germany can boast many extra authors than their western counterparts.

We additionally discovered that 99.95% of the cited references had been written in English. We estimate that the ultimate quotation checklist included solely 11 non-English language references, with 4 in French, 4 in Spanish, two in German and one in Portuguese. 

Nonetheless, not all references assessed in IPCC stories find yourself being cited within the ultimate product because the sheer quantity of accessible literature makes it not possible to quote the whole lot within the report. Which means that many extra papers could have been assessed than these included in our evaluation. 

For instance, the WG1 writer survey ran from February to March 2022 and picked up suggestions from over 150 WG1 authors and assessment editors on the successes, challenges and classes realized from the WG1 AR6 expertise. Round 20% of the survey respondents stated that non-English literature was assessed of their chapter – together with analysis in Arabic, Bangla, Chinese language, Farsi, French, German, Italian, Japanese, Portuguese, Russian, Spanish and Ukrainian. 

Topping the tables

The authors of papers cited within the WG1 report hail from greater than 2,500 establishments world wide. Essentially the most generally cited establishment is the Centre nationwide de la recherche scientifique (CNRS) – an amalgamation of a number of establishments based mostly in France, whose consultants contributed virtually 11% of the entire citations. 

Virtually the entire prime 100 establishments are based mostly within the world north. Maybe this imbalance isn’t any enormous shock, contemplating the shortage of variety in local weather analysis and that the costly, resource-intense world local weather mannequin analysis centres are predominantly based mostly in world north international locations. The regional imbalance in local weather analysis filters by means of to an imbalance within the report citations.

The desk under exhibits the highest 15 establishments, the nation they’re based mostly in and the share of citations within the AR6 WG1 report that embody not less than one writer from that establishment.

EstablishmentNationProportion of citations

1Centre nationwide de la recherche scientifique (CNRS)France11%

2National Oceanic and Atmospheric Administration (NOAA)US9%

3National Centre for Atmospheric Analysis (NCAR)US7%

4Université Paris Sciences et LettresFrance7%

5UK Met OfficeUK7%

6Université de ParisFrance7%

7École PolytechniqueFrance7%

8Institute Polytechnique de ParisFrance7%

9Institute de Recherche pour le Développement (IRD)France6%

10Le Commissariat à l’Energie Atomique et aux Energies Options (CEA)France6%

11Swiss Federal Institute of Expertise ZurichSwitzerland6%

12Columbia UniversityUS5%

13Chinese Academy of SciencesChina5%

14Centre Nationwide d’Etudes Spatiales (CNES)France5%

15University of ReadingUK5%

The highest 15 most represented establishments within the WG1 references and the share of the citations inside which they seem.

We additionally checked out which journals had been cited most incessantly. Virtually the entire WG1 citations are scientific articles, that are revealed in peer-reviewed, educational journals. (In the meantime, 4% are labeled as technical stories or books – often called “gray literature”.)

In complete, there are greater than 800 distinctive journals represented within the WG1 checklist of citations. The desk under exhibits the ten most extremely cited journals throughout the references. It contains the nation that the writer relies in and whether or not the journal is open-access – that means that anybody can entry papers revealed within the journal at no cost.

JournalVariety of instances citedNation
Open entry by default?

1Geophysical Analysis Letters1.561USYes, as of Jan 2023

2Journal of Climate1,537USAfter one 12 months

3Climate Dynamics1,075GermanyNo

4Nature Local weather Change740GermanyNo

5Environmental Analysis Letters618UKYes

6Nature 531GermanyNo

7International Journal of Climatology516USNo

8Atmospheric Chemistry and Physics490GermanyYes

9Nature Geoscience 424GermanyNo

10Proceedings of the Nationwide Academy of Sciences416USAfter six months

The highest 10 most extremely cited journals discovered within the IPCC WG1 quotation checklist, noting their corresponding writer and whether or not they’re open entry by default.

Essentially the most extremely cited journal throughout all chapters was Geophysical Analysis Letters with 1,561 citations within the WG1 references, comparable to round 1,200 distinctive papers. 

Most of those 10 journals should not open-access by default or require authors to pay further charges for his or her paper to be an open-access publication. Subscriptions and processing charges could be a enormous barrier to participation for teachers, significantly for these from the worldwide south. 

The push in direction of open-access science doesn’t at all times cut back up-front publication charges for researchers, however does enable for the ultimate materials to be accessed at no cost. Universities and researchers are nonetheless paying excessive charges to entry and publish their analysis regardless of many objections. 


To discover which subject areas are mostly cited, we used a instrument referred to as SciVal to robotically assign subject labels to every of the WG1 citations. The WG1 literature foundation has hyperlinks to a surprisingly broad choice of analysis themes.

That is illustrated within the determine under, which exhibits a wheel of analysis disciplines and the place clusters of those assigned WG1 quotation subjects match. Every dot represents a selected cluster of subjects and its dimension signifies the variety of instances they seem within the WG1 citations. The color corresponds to the scientific self-discipline that subject is related to, as assigned by SciVal.

WG1 report citations categorised into ‘clusters’ of research topics.WG1 report citations categorised into ‘clusters’ of analysis subjects. All subjects and the way they’re clustered are robotically assigned by SciVal. Dots signify a selected cluster of subjects. The dimensions of the dots signify the variety of instances that cluster seems within the WG1 references. The color corresponds to the scientific self-discipline that the subject is related to. Scientific disciplines are divided up into the checklist proven within the backside panel. Map created utilizing SciVal. Credit score: Félix Chavelli

Greater than half of all WG1 citations are linked with the subject cluster “Local weather fashions, Mannequin, Rain”, which sits among the many bodily, chemical and environmental science disciplines, and is illustrated by the big mild inexperienced circle within the determine.

Many citations are linked to analysis disciplines not normally related to the WG1 report, however these replicate a rising curiosity within the cross-disciplinary nature of local weather change – even in a report based mostly on the bodily science of local weather change.

For instance, the subject cluster “Salmonella, Escherichia Coli, Listeria Monocytogenes”, which incorporates citations labeled underneath the medical analysis self-discipline, however the truth is covers how bodily local weather traits comparable to temperature can alter ailments. In one other instance, “Tourism, Vacationers, Vacation spot” is a cluster linked to the enterprise scientific self-discipline that features citations protecting local weather providers linked to snowfall projections for ski resorts.

Lastly, we explored the variations in citations between chapters. Following on from the introduction in Chapter 1, the WG1 report is break up in three sections:

  • Massive-scale local weather change (Chapters 2–4)
  • Local weather system parts and processes (Chapters 5–9)
  • Regional local weather data (Chapters 10-Atlas)
  • Of the 13,000 citations within the report, round 4,500 are cited in a number of chapters. About 2,000 references are cited in two chapters, over 500 seem in three chapters and simply over 200 are cited in 4 or extra chapters.

    As a result of their comparable themes, chapters 8 (“Water cycle adjustments”) and 11 (“Climate and local weather excessive occasions in a altering local weather”), 11 and 12 (“Local weather change data for regional affect and for threat evaluation”) and eight and 10 (“Linking world to regional local weather change”) share essentially the most citations.

    For extra data on the IPCC WG1 references and this evaluation, try the accompanying report or you possibly can obtain the citations your self from the WG1 web site.

    Particular thanks to Robin Matthews, former senior science officer on the Working Group I Technical Help Unit, for his high quality management of the WG1 chapter quotation lists.

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