Planetary Boundaries: Guiding Human Development on a Changing Planet
Science, 2015 · paper · Earth science
Updates the planetary boundaries framework, which sets limits on human disturbance of Earth's systems to keep a safe operating space. It finds that four processes (climate change, biosphere integrity, biogeochemical flows, land-system change) exceed the proposed boundaries.
4 findings
Substance Basin-scale freshwater boundary for intermediate-flow months: Table 1 prints "30% (30–60%)", the text prints "40 to 70% for the intermediate-flow regime".
- p. 6 Table 1 (continued), Freshwater use, Basin row
flow months: 30% (30–60%)
- p. 8 Freshwater use, second paragraph
40 to 70% for the intermediate-flow regime
- p. 8 Freshwater use, second paragraph
40 to 70% for
- p. 6 Table 1, Freshwater use, Basin boundary
for intermediate-flow months: 30% (30–60%)
Only the authors can say what is right here.
Judge's note: Table 1 on page 6: "For low-flow months: 25% (25–55%); for intermediate-flow months: 30% (30–60%); for high-flow months: 55% (55–85%)". Text on page 8: "25 to 55% of MMF for the low-flow regime, 40 to 70% for the intermediate-flow regime, and 55 to 85% for the high-flow regime (table S2). The boundaries were set at the lower end of the uncertainty ranges". The low-flow and high-flow ranges are identical in both places, so the same quantity is meant and only the intermediate value differs; by the text's rule the boundary would be 40%, against 30% in the table. I found no statement in the article explaining the difference. Table S2 is not among the files, so which value is right cannot be said.
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Reference or label The summary-page figure labels the wedge "Biochemical flows"; the same diagram in Fig. 3, Table 1 and the text (including the summary text on the same page) call it "Biogeochemical flows".
- p. 1 Summary figure, label at bottom left
Biochemical flows
- p. 7 Fig. 3, same label
Biogeochemical flows
Judge's note: Read on the page 1 image: the bottom-left label reads "Biochemical flows" above the Phosphorus and Nitrogen wedges. The results text on the same page says "biogeochemical flows" twice. Not an extraction artefact. Evident fix: "Biogeochemical flows".
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Reference or label Page 10, Methods summary: "nitrogen (5), biosphere integrity (7), freshwater use (5, 63)" cites reference 5 (de Vries et al., "Assessing planetary and regional nitrogen boundaries related to food security and adverse environmental impacts") for freshwater use; the freshwater-use assessment is reference 6 (Gerten et al., "Towards a revised planetary boundary for consumptive freshwater use"), which is absent from this list.
- p. 10 Methods summary, end of first column
trogen (5), biosphere integrity (7), freshwater use
- p. 10 Methods summary, continuation
(5, 63), and novel entities
- p. 10 Reference 6
D. Gerten et al., Towards a revised planetary boundary for
- p. 10 Methods summary, last paragraph
freshwater use
Judge's note: Read the sentence and references 5 and 6 on the crops and the full page. Reference 5 is cited for nitrogen and again for freshwater use in the same sentence; its title concerns nitrogen only. Reference 6 is the post-2009 freshwater boundary assessment and is the one cited for the freshwater PB on page 8 ("depending on rivers' ecological flow requirements (6)"). Nothing in the text explains citing reference 5 for freshwater. Evident fix: (6, 63).
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Wording Page 12, journal summary: "Of the original nine proposed boundaries, they identify three (including climate change) that might push the Earth system into a new state if crossed and that also have a pervasive influence on the remaining boundaries" says three; the article identifies two core boundaries ("Two core boundaries—climate change and biosphere integrity—have been identified").
- p. 12 Editor's summary, "Crossing the boundaries in global sustainability"
identify three (including climate change) that might push the Earth system into a new state
- p. 2 Abstract
Two core boundaries—climate change and biosphere integrity—have been
- p. 12 Editor's summary
they identify three (including climate change) that might push the Earth system into a new state if crossed
- p. 9 Hierarchy of boundaries
climate change and biosphere integrity should be recognized as core
Judge's note: Read the summary on the page 12 image and the abstract and the Hierarchy section on the crops. The abstract (page 2), the summary page ("Two of the PBs—climate change and biosphere integrity—are recognized as 'core' PBs"), the introduction ("identifying two core boundaries") and page 9 ("climate change and biosphere integrity should be recognized as core planetary boundaries") all give two. No passage counts three; biosphere integrity has two components but is treated as one boundary. The text is the journal's own summary on the publisher's information page, not the authors' text, which is why it is graded S3 and not S1; it is within the PDF pages in scope and misstates the article's count.
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21 minor (typos and the like; most checked by the judge only)
Reference or label Table 1 names the second climate control variable "Energy imbalance at top-of-atmosphere, W m–2", while the text defines it as "an increase in top-of-atmosphere radiative forcing of +1.0 W m–2 relative to preindustrial levels" and gives the same current value, "+2.3 W m–2 (1.1 to 3.3 W m–2) in 2011 relative to 1750", as radiative forcing.
- p. 5 Table 1, Climate change, control variable
Energy imbalance
- p. 4 Climate change, first paragraph
increase in top-of-atmosphere radiative forcing of
- p. 4 Climate change, second paragraph
and +2.3 W m–2 (1.1 to 3.3 W m–2) in 2011 relative
Only the authors can say what is right here.
Judge's note: Table 1 on page 5 prints "Energy imbalance at top-of-atmosphere" with boundary +1.0 (+1.0–1.5) and current value 2.3 (1.1–3.3) W m–2. The text on page 4 gives the same numbers under the name radiative forcing, repeatedly. The numbers agree; the label differs. That energy imbalance and radiative forcing are different physical quantities is general knowledge, not stated in the paper, so this is a labelling query for the authors.
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Wording "The subglobal-level units of analysis for these six boundaries are not identical" follows "We focus on the five PBs that have strong regional operating scales" (five are named), and only four units, (i) to (iv), are then listed; later the text again says "five of the PBs".
- p. 4 Linking global and regional scales, first column
of analysis for these six boundaries are not
- p. 3 Linking global and regional scales, third column
We focus on the five PBs that have strong re-
- p. 4 Updates of the individual boundaries
above are particularly important for five of the
- p. 4 first paragraph
The subglobal-level units of analysis for these six boundaries
Only the authors can say what is right here.
Judge's note: Read on pages 3 and 4. Page 3 names biosphere integrity, biogeochemical flows, land-system change, freshwater use and atmospheric aerosol loading. Page 4 says "these six boundaries" and lists (i) biosphere integrity, (ii) land-system change, (iii) freshwater, (iv) biogeochemical flows, with no item for aerosol loading. No six-member set is defined anywhere in the article; counting P and N separately would give six, but the paper does not say so and treats them as one item in (iv). A count inconsistency in the prose; no data value is affected.
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Wording The nitrogen paragraph says a redistribution of N could "reduce the transgression of the regional-level boundary", but the article defines only a global N boundary (Table 1: "N Global", 62 Tg N yr–1); a regional-level boundary is defined for P only.
- p. 8 Biogeochemical flows, N paragraph
tion and reduce the transgression of the regional-
- p. 5 Table 1, Biogeochemical flows
N Global
Only the authors can say what is right here.
Judge's note: Page 8 text and Table 1 on page 5. The preceding P paragraph ends with the parallel phrase "the regional-level P boundary", which is defined (6.2 Tg P per year). For N, Table 1 lists only "N Global" and adds that "regional distribution of fertilizer N is critical for impacts"; Fig. 2B maps N status regionally. So a regional view of N exists, but no regional-level N boundary is stated in the article and the phrase is left without a referent. Details may be in the supplement, which is not among the files.
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Wording Table 1 defines the regional aerosol control variable as "AOD as a seasonal average over a region", but the current status is given as "The annual mean AOD is currently about 0.3 (66), within the zone of uncertainty".
- p. 6 Table 1 (continued), Atmospheric aerosol loading, control variable
a seasonal average
- p. 8 Atmospheric aerosol loading, second paragraph
mean AOD is currently about 0.3 (66), within the
Judge's note: Both are on the page images (Table 1 on page 6, text on page 8). The same paragraph speaks of "seasonal mean AODs" as high as 0.4. The averaging period of the value compared with the boundary differs from the defined control variable and the paper does not comment on it. Either 0.3 or 0.4 lies within 0.25–0.50, so the stated status is unchanged.
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Wording Table 1 gives the aerosol boundary as "anthropogenic total (absorbing and scattering) AOD over Indian subcontinent of 0.25 (0.25–0.50)", whereas the text sets "a boundary at an AOD of 0.25 (an increase due to human activities of 0.1)" on a background of ~0.15.
- p. 6 Table 1, Atmospheric aerosol loading, boundary
anthropogenic total (absorbing
- p. 8 Atmospheric aerosol loading, second paragraph
(an increase due to human activities of 0.1)
Only the authors can say what is right here.
Judge's note: Table 1 on page 6 and the text on page 8 read as quoted. In the text 0.25 is the total AOD, of which 0.1 is anthropogenic; the table's wording attaches "anthropogenic" to 0.25. The table's current value, "0.30 AOD", matches the text's annual mean total AOD of about 0.3, which indicates the table's 0.25 is also meant as total AOD. The word "anthropogenic" in the table is therefore ambiguous or misplaced.
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Typo The Wageningen postcode is printed "6700AA Wageningen" in affiliation 7 and "6700 AA Wageningen" in affiliation 8.
- p. 2 affiliations 7 and 8
P.O. Box 47, 6700AA Wageningen
Judge's note: Both forms are visible in the affiliation block on the crop. Formatting inconsistency only.
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Typo "large thresholds [e.g, loss of the Greenland ice sheet (18)]" lacks the period after "g"; elsewhere the paper prints "e.g.,".
- p. 3 Second column, sentence on natural carbon sinks
large thresholds [e.g, loss of the Greenland ice
- p. 3 Introduction to boundaries section, climate-sink example
[e.g, loss of the Greenland ice
Judge's note: The crop shows "[e.g, loss" with no period after g. Other instances in the text are "e.g.," (for example "[e.g., (94)]" on page 9).
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Typo The text introducing Figure 2 says "biogeochemical cycles, land-system change, and freshwater use", where the boundary is named "biogeochemical flows" (as in the Fig. 2 legend, "biogeochemical flows of P").
- p. 4 Updates / Figure 2 paragraph
biogeochemical cycles, land-system change, and freshwater use
- p. 4 Fig. 2 legend
biogeochemical flows of P
Judge's note: Both wordings are on page 4. The paper states that "biogeochemical flows" replaces the earlier "phosphorus (P) and nitrogen (N) cycles", so "cycles" here is loose usage for the same boundary. Terminology only; the meaning is clear.
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Typo "The biome-level boundary for these two types of forest have been set at 85%": singular subject with plural verb.
- p. 8 Land-system change, second paragraph
forest have been set at 85% (Table 1 and the
- p. 8 Land-system change, second paragraph
forest have been set at 85%
- p. 8 Land-system change, second paragraph
The biome-level boundary for these two types of forest have been set at 85%
Judge's note: Read on the page 8 image, second column. Grammar only; the meaning is unaffected.
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Typo Page 9, Novel entities: "disrupt the functioning of the Earth-system and society needs to learn how to mitigate these unknown risks" hyphenates the noun "Earth system", which the paper writes unhyphenated as a noun everywhere else (the hyphen is used only for the adjectival form, e.g. "Earth-system functioning").
- p. 9 Novel entities, final paragraph
disrupt the functioning of the Earth-system and society needs to learn
Judge's note: Read on the crop. The same crop shows the noun form "the state of the Earth system" and "of the Earth system to persist" unhyphenated, and the adjectival "Earth-system functioning" hyphenated. A search of the text finds the noun unhyphenated throughout (pages 2, 3, 4, 8, 9, 10); this is the only hyphenated noun use. The missing comma before "and society" is a style point and not part of the verdict.
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Typo Page 10, reference 15: "W. Steffen, J. Crutzen, J. R. McNeill, The Anthropocene: Are humans now overwhelming the great forces of Nature?" gives the second author as "J. Crutzen", whereas reference 19 gives "P. J. Crutzen".
- p. 10 Reference 15
W. Steffen, J. Crutzen, J. R. McNeill, The Anthropocene: Are
- p. 10 Reference 19
P. J. Crutzen, Geology of mankind.
- p. 10 Reference 15
W. Steffen, J. Crutzen, J. R. McNeill
- p. 10 Reference 19
P. J. Crutzen, Geology of mankind
Only the authors can say what is right here.
Judge's note: Rests on outside knowledge: that the second author of the 2007 Ambio paper is P. J. Crutzen, the same person as the author of reference 19. Both entries read on the crops: reference 15 prints "J. Crutzen" and reference 19 prints "P. J. Crutzen". The two forms within one reference list support a dropped initial, but the author list of the cited work is not in the files.
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Typo Page 10, reference 17: "C.B. Field et al., Eds. (Cambridge University Press, Cambridge, UK (2012). doi: 10.1017/CBO9781139177245" has an unbalanced parenthesis: the one opened before the publisher is never closed, and a second opens before the year.
- p. 10 Reference 17
University Press, Cambridge, UK (2012).
- p. 10 Reference 17
Cambridge University Press, Cambridge, UK (2012).
Judge's note: Read on the crop. Other book entries on the same page use the form "(Publisher, City, Year)", for example reference 18 "(IPCC Secretariat, Geneva, Switzerland, 2013)" and reference 20 "(Cambridge Univ. Press, Cambridge, UK, 2011)". Reference 17 should read "(Cambridge University Press, Cambridge, UK, 2012)".
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Typo Page 10, reference 10: "WBCSD (World Business Council on Sustainable Development)" expands the acronym with "on"; the organisation's name is World Business Council for Sustainable Development.
- p. 10 Reference 10
WBCSD (World Business Council on Sustainable Development)
Only the authors can say what is right here.
Judge's note: Rests on outside knowledge: the organisation's official name uses "for", not "on". The page prints the text as quoted (read on the crop). Nothing else in the paper gives the name, so this cannot be checked from the files.
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Typo Page 10, reference 43: "doi: 10.1038/nature11118;pmid: 22678289" lacks the space after the semicolon that other entries have ("; pmid:").
- p. 10 Reference 43
nature11118;pmid: 22678289
Judge's note: Read on the crop: no space between the DOI's semicolon and "pmid" in reference 43, whereas references 19, 21, 41 and 42 in the same view print "; pmid:". Cosmetic. Reference 46 has the same slip (C022), a separate location.
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Typo Page 10, reference 46: "doi: 10.1196/annals.1439.013;pmid: 18566099" lacks the space after the semicolon that other entries have ("; pmid:").
- p. 10 Reference 46
annals.1439.013;pmid: 18566099
Judge's note: Read on the crop: reference 46 prints ";pmid:" with no space, whereas references 19 and 21 in the same view print "; pmid:". Cosmetic. Same kind of slip as C021 but in a different entry, so not a duplicate.
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Typo Page 10, reference 13: "R. C. Bishop, Endangered species and uncertainty: The economics of a safe minimum standard. Am. J. Agric. Econ. 61, 10–18 (1978). doi: 10.2307/1240156" prints volume 61; Crossref's record for this DOI gives volume 60.
- p. 10
R. C. Bishop, Endangered species and uncertainty: The economics of a safe minimum standard
Only the authors can say what is right here.
Judge's note: Rests on outside knowledge: the Crossref record for doi 10.2307/1240156 gives volume 60 (the journal's 1978 volume). The page prints a bold "61" as quoted (read on the crop). The true volume cannot be verified from the files; the printed DOI still identifies the work.
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Typo Page 11, Acknowledgments: "We thank J. Foley and N. Ramunkutty for contributions to the land-system change boundary" spells the name "Ramunkutty"; reference 52 on the same page prints "N. Ramankutty".
- p. 11 Acknowledgments, first line
N. Ramunkutty
- p. 11 Reference 52
N. Ramankutty
- p. 11
J. Foley and N. Ramunkutty for contributions
Judge's note: Both spellings read on the crops: "N. Ramunkutty" in the acknowledgments and "N. Ramankutty" as the last author of reference 52. Same initial and field (land use), thanked alongside J. Foley, so evidently one person; the reference-list spelling is that of the published author name.
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Typo Page 11, reference 82: "T. Lenton, A. Watson, A., Revolutions That Made the Earth (Oxford Univ. Press, Oxford UK, 2011)." has a stray repeated initial "A.," after the second author.
- p. 11 Reference 82
T. Lenton, A. Watson, A., Revolutions That Made the Earth
Judge's note: Read on the crop: "T. Lenton, A. Watson, A., Revolutions That Made the Earth". No other entry in the list has an initial after a surname in this style (the list uses initials before surnames), and no editor marker is indicated. A leftover from a surname-first format.
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Typo Page 11, reference 62: "N. L. Poff, J. K. H. Zimmerman, Ecological responses to altered flow regimes: A literature review to inform the science and management of environmental flows. Biol. 55, 194–205 (2010). doi: 10.1111/j.1365-2427.2009.02272.x" gives the journal as "Biol." only; the journal name appears truncated (Freshwater Biology, "Freshw. Biol.").
- p. 11 Reference 62
management of environmental flows. Biol. 55, 194–205 (2010).
Only the authors can say what is right here.
Judge's note: Rests on outside knowledge: that the DOI prefix 10.1111/j.1365-2427 (ISSN 1365-2427) belongs to Freshwater Biology and that this article appeared there. The page prints an italic "Biol." followed by a bold 55, as quoted (read on the crop). "Biol." alone does not identify a journal, but the correct title is not stated anywhere in the files.
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Typo Page 11, Acknowledgments: "S.S. is supported by the Riksbanken Jubileumsfond and the Institute for Advanced Study" spells the funder "Riksbanken Jubileumsfond"; the foundation's name is Riksbankens Jubileumsfond.
- p. 11 Acknowledgments
Riksbanken Jubileumsfond
Only the authors can say what is right here.
Judge's note: Rests on outside knowledge: the Swedish foundation's name is "Riksbankens Jubileumsfond" (genitive -s). The page prints "Riksbanken Jubileumsfond" as quoted (read on the crop). The name appears nowhere else in the files.
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Typo Page 11, reference 57: "Front. Ecol. Environ 9, 126–133 (2010). doi: 10.1890/090015" pairs volume 9 with 2010, while reference 48 gives "Front. Ecol. Environ 10, 243–248 (2012)"; with one volume per year, volume 9 is 2011.
- p. 11 Reference 57
Front. Ecol. Environ 9, 126–133 (2010)
- p. 11 Reference 48
Front. Ecol. Environ 10, 243–248 (2012)
Only the authors can say what is right here.
Judge's note: Rests on outside knowledge: that Frontiers in Ecology and the Environment publishes one volume per calendar year, so that volume 9 is 2011. Both entries read on the crops as quoted. The 2010 date may be the online-first year of the article (the DOI suffix 090015 indicates a 2009 submission), so either the year or the convention differs; only the authors or the journal can say which is intended. Both entries also omit the period after "Environ".
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