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{{Short description|Limits not to be exceeded if humanity wants to survive in a safe ecosystem}}{{Distinguish|Planetary boundary layer}}{{Use dmy dates|date=August 2021}}File:PBs2023.png|thumb|Visualizations of the Planetary Boundaries; data for September 2023JOURNAL, Richardson, Katherine, Steffen, Will, Lucht, Wolfgang, 2023, Earth beyond six of nine planetary boundaries, Science AdvancesScience AdvancesPlanetary boundaries are a framework to describe limits to the impacts of human activities on the Earth system. Beyond these limits, the environment may not be able to self-regulate anymore. This would mean the Earth system would leave the period of stability of the Holocene, in which human society developed.JOURNAL, Rockström, Johan, Steffen, Will, Noone, Kevin, Persson, Ã…sa, Chapin, F. Stuart, Lambin, Eric F., Lenton, Timothy M., Scheffer, Marten, Folke, Carl, Schellnhuber, Hans Joachim, Nykvist, Björn, 2009, A safe operating space for humanity, Nature (journal), Nature, en, 461, 7263, 472–475, 10.1038/461472a, 19779433, 2009Natur.461..472R, 205049746, 0028-0836, free, JOURNAL, Rockström, Johan, Steffen, Will, Noone, Kevin, Persson, Ã…sa, Chapin, F. Stuart III, Lambin, Eric, Lenton, Timothy M., Scheffer, Marten, Folke, Carl, Schellnhuber, Hans Joachim, Nykvist, Björn, 2009, Planetary Boundaries: Exploring the Safe Operating Space for Humanity,www.ecologyandsociety.org/vol14/iss2/art32/, Ecology and Society, en, 14, 2, art32, 10.5751/ES-03180-140232, 15182169, 1708-3087, free, 10535/5421, free, JOURNAL, Rockström, Johan, Gupta, Joyeeta, Qin, Dahe, Lade, Steven J., Abrams, Jesse F., Andersen, Lauren S., Armstrong McKay, David I., Bai, Xuemei, Bala, Govindasamy, Bunn, Stuart E., Ciobanu, Daniel, DeClerck, Fabrice, Ebi, Kristie, Gifford, Lauren, Gordon, Christopher, Hasan, Syezlin, Kanie, Norichika, Lenton, Timothy M., Loriani, Sina, Liverman, Diana M., Mohamed, Awaz, Nakicenovic, Nebojsa, Obura, David, Ospina, Daniel, Prodani, Klaudia, Rammelt, Crelis, Sakschewski, Boris, Scholtens, Joeri, Stewart-Koster, Ben, Tharammal, Thejna, van Vuuren, Detlef, Verburg, Peter H., Winkelmann, Ricarda, Zimm, Caroline, Bennett, Elena M., Bringezu, Stefan, Broadgate, Wendy, Green, Pamela A., Huang, Lei, Jacobson, Lisa, Ndehedehe, Christopher, Pedde, Simona, Rocha, Juan, Scheffer, Marten, Schulte-Uebbing, Lena, de Vries, Wim, Xiao, Cunde, Xu, Chi, Xu, Xinwu, Zafra-Calvo, Noelia, Zhang, Xin, Safe and just Earth system boundaries, Nature (journal), Nature, 2023, 619, 7968, 102–111, 10.1038/s41586-023-06083-8, 37258676, 10322705, 2023Natur.619..102R, free, The framework is based on scientific evidence that human actions, especially those of industrialized societies since the Industrial Revolution, have become the main driver of global environmental change. According to the framework, “transgressing one or more planetary boundaries may be deleterious or even catastrophic due to the risk of crossing thresholds that will trigger non-linear, abrupt environmental change within continental-scale to planetary-scale systems.“The normative component of the framework is that human societies have been able to thrive under the comparatively stable climatic and ecological conditions of the Holocene. To the extent that these Earth system process boundaries have not been crossed, they mark the “safe zone” for human societies on the planet. Proponents of the planetary boundary framework propose returning to this environmental and climatic system; as opposed to human science and technology deliberately creating a more beneficial climate. The concept doesn’t address how humans have massively altered ecological conditions to better suit themselves. The climatic and ecological Holocene this framework considers as a “safe zone” doesn’t involve massive industrial farming. So this framework begs a reassessment of how to feed modern populations.The concept has since become influential in the international community (e.g. United Nations Conference on Sustainable Development), including governments at all levels, international organizations, civil society and the scientific community. The framework consists of nine global change processes. In 2009, according to Rockström and others, three boundaries were already crossed (biodiversity loss, climate change and nitrogen cycle), while others were in imminent danger of being crossed.JOURNAL, 2009, Earth’s boundaries?, Nature (journal), Nature, en, 461, 7263, 447–448, 10.1038/461447b, 19779405, 2009Natur.461R.447., 29052784, 0028-0836, free, In 2015, several of the scientists in the original group published an update, bringing in new co-authors and new model-based analysis. According to this update, four of the boundaries were crossed: climate change, loss of biosphere integrity, land-system change, altered biogeochemical cycles (phosphorus and nitrogen). The scientists also changed the name of the boundary “Loss of biodiversity” to “Change in biosphere integrity” to emphasize that not only the number of species but also the functioning of the biosphere as a whole is important for Earth system stability. Similarly, the “Chemical pollution” boundary was renamed to “Introduction of novel entities”, widening the scope to consider different kinds of human-generated materials that disrupt Earth system processes.In 2022, based on the available literature, the introduction of novel entities was concluded to be the 5th transgressed planetary boundary. Freshwater change was concluded to be the 6th transgressed planetary boundary in 2023.{{TOC limit|3}}

Framework overview and principles

The basic idea of the Planetary Boundaries framework is that maintaining the observed resilience of the Earth system in the Holocene is a precondition for humanity’s pursuit of long-term social and economic development.{{sfn|Rockström|28 others|2009}} The Planetary Boundaries framework contributes to an understanding of global sustainability because it brings a planetary scale and a long timeframe into focus.The framework described nine “planetary life support systems” essential for maintaining a “desired Holocene state”, and attempted to quantify how far seven of these systems had been pushed already. Boundaries were defined to help define a “safe space for human development”, which was an improvement on approaches aiming at minimizing human impacts on the planet.{{sfn|Rockström|28 others|2009}}The framework is based on scientific evidence that human actions, especially those of industrialized societies since the Industrial Revolution, have become the main driver of global environmental change. According to the framework, “transgressing one or more planetary boundaries may be deleterious or even catastrophic due to the risk of crossing thresholds that will trigger non-linear, abrupt environmental change within continental-scale to planetary-scale systems.“{{sfn|Rockström|28 others|2009}} The framework consists of nine global change processes. In 2009, two boundaries were already crossed, while others were in imminent danger of being crossed. Later estimates indicated that three of these boundaries—climate change, biodiversity loss, and the biogeochemical flow boundary—appear to have been crossed.The scientists outlined how breaching the boundaries increases the threat of functional disruption, even collapse, in Earth’s biophysical systems in ways that could be catastrophic for human wellbeing. While they highlighted scientific uncertainty, they indicated that breaching boundaries could “trigger feedbacks that may result in crossing thresholds that drastically reduce the ability to return within safe levels”. The boundaries were “rough, first estimates only, surrounded by large uncertainties and knowledge gaps” which interact in complex ways that are not yet well understood.{{sfn|Rockström|28 others|2009}}The planetary boundaries framework lays the groundwork for a shifting approach to governance and management, away from the essentially sectoral analyses of limits to growth aimed at minimizing negative externalities, toward the estimation of the safe space for human development.JOURNAL, Kim, Rakhyun E., Kotzé, Louis J., 2021, Planetary boundaries at the intersection of Earth system law, science and governance: A state‐of‐the‐art review,onlinelibrary.wiley.com/doi/10.1111/reel.12383, Review of European, Comparative & International Environmental Law, en, 30, 1, 3–15, 10.1111/reel.12383, 2050-0386, Planetary boundaries demarcate, as it were, the “planetary playing field” for humanity if major human-induced environmental change on a global scale is to be avoided.

Authors

The authors of this framework was a group of Earth System and environmental scientists in 2009 led by Johan Rockström from the Stockholm Resilience Centre and Will Steffen from the Australian National University. They collaborated with 26 leading academics, including Nobel laureate Paul Crutzen, Goddard Institute for Space Studies climate scientist James Hansen, oceanographer Katherine Richardson, geographer Diana Liverman and the German Chancellor’s chief climate adviser Hans Joachim Schellnhuber.Most of the contributing scientists were involved in strategy-setting for the Earth System Science Partnership, the precursor to the international global change research network Future Earth. The group wanted to define a “safe operating space for humanity” for the wider scientific community, as a precondition for sustainable development.

Nine boundaries

Thresholds and tipping points

The 2009 study identified nine planetary boundaries and, drawing on current scientific understanding, the researchers proposed quantifications for seven of them. These are:

1. climate change (CO2 concentration in the atmosphere

Related concepts

Planetary integrity

{{See also|Sustainable Development Goals#Weak on environmental sustainability}}Planetary integrity is also called earth’s life-support systems or ecological integrity.

• {{Citation |last1=Bass |first1=S. |title=Planetary boundaries: Keep off the grass |department=[commentary] |journal=Nature Reports Climate Change |issue=910 |page=113 |date=2009 |volume=1 |doi=10.1038/climate.2009.94 |doi-access=free}}

• {{Citation |last1=Brewer |first1=P. |title=Planetary boundaries: Consider all consequences |department=[commentary] |journal=Nature Reports Climate Change |issue=910 |page=117 |date=2009 |volume=1 |doi=10.1038/climate.2009.98 |doi-access=free}}
• JOURNAL, Cordell, Dana, Dana Cordell, Drangert, Jan-Olof, White, Stuart, The story of phosphorus: Global food security and food for thought, Global Environmental Change, 19, 2, 2009, 292–305, 0959-3780, 10.1016/j.gloenvcha.2008.10.009, 1450932,
• {{citation |author1-link=Paul J. Crutzen |first1=Paul J. |last1=Crutzen |date=3 January 2002 |title=Geology of mankind – The Anthropocene |journal=Nature |volume=415 |issue=6867 |pages=23 |doi=10.1038/415023a |pmid=11780095 |bibcode=2002Natur.415...23C |s2cid=9743349 |doi-access=free}}
• {{citation |ref={{sfnref|Dansgaard|others|1993}} |display-authors=4 |first1=W. |last1=Dansgaard |first2=S.J. |last2=Johnsen |first3=H.B. |last3=Clausen |first4=D. |last4=Dahl-Jensen |first5=N.S. |last5=Gundestrup |first6=C.U. |last6=Hammer |first7=C.S. |last7=Hvidberg |first8=J.P. |last8=Steffensen |first9=A.E. |last9=Sveinbjörnsdottir |first10=J. |last10=Jouzel |first11=G. |last11=Bond |author-link1=Willi Dansgaard |author-link4=Dorthe Dahl-Jensen |name-list-style=amp |date=15 July 1993 |title=Evidence for general instability of past climate from a 250-kyr ice-core record |journal=Nature |volume=364 |pages=218–20 |url=http://earthsciences.ucr.edu/gcec_pages/docs/geo224/Dansgaard%20et%20al%201993-Nature-Evidence%20for%20generalinstability%20of%20past%20climate%20from%20a%20250-kyrice-core%20record.pdf |doi=10.1038/364218a0 |bibcode=1993Natur.364..218D |issue=6434 |s2cid=4304321 |access-date=7 July 2011 |archive-date=3 October 2011 |archive-url=https://web.archive.org/web/20111003153658earthsciences.ucr.edu/gcec_pages/docs/geo224/Dansgaard%20et%20al%201993-Nature-Evidence%20for%20generalinstability%20of%20past%20climate%20from%20a%20250-kyrice-core%20record.pdf |url-status=live}}
• {{Citation |ref=CITEREFFolkeothers2004 |last1=Folke |first1=C. |last2=Carpenter |first2=S. |last3=Walker |first3=B. |last4=Scheffer |first4=M. |last5=Elmqvist |first5=T. |last6=Gunderson |first6=L. |last7=Holling |first7=C. S. |title=Regime Shifts, Resilience, and Biodiversity in Ecosystem Management |journal=Annual Review of Ecology, Evolution, and Systematics |volume=35 |pages=557–81 |year=2004 |doi=10.1146/annurev.ecolsys.35.021103.105711 |url=http://www.colorado.edu/AmStudies/lewis/ecology/ecobiodiver.pdf |url-status=dead |archive-url=https://web.archive.org/web/20121018074852www.colorado.edu/AmStudies/lewis/ecology/ecobiodiver.pdf |archive-date=18 October 2012 |citeseerx=10.1.1.489.8717}}
• {{Citation |last1=Gordon |first1=L. J. |last2=Peterson |first2=G. D. |last3=Bennett |first3=E. M. |title=Agricultural modifications of hydrological flows create ecological surprises |journal=Trends in Ecology & Evolution |date=2008 |volume=23 |issue=4 |pages=211–19 |doi=10.1016/j.tree.2007.11.011 |pmid=18308425 |url=http://nrs-staff.mcgill.ca/bennett/pdfs/Gordon_etal.TREE.pdf |access-date=26 October 2011 |archive-date=1 June 2011 |archive-url=https://web.archive.org/web/20110601031842nrs-staff.mcgill.ca/bennett/pdfs/Gordon_etal.TREE.pdf |url-status=live}}
• {{citation |first1=O. |last1=Greenfield |date=April 2010 |title=Discussion input for the 4th session: Corporate social responsibility in a globalised economy &91;meeting abstract&93; |at=European Conference: “Towards a Greater Understanding of the Changing Role of Business in Society”, Brussels, 22 April 2010 |url=http://ec.europa.eu/research/social-sciences/pdf/14-4th-session-oliver-greefield_en.pdf |access-date=3 July 2011 |archive-date=3 November 2012 |archive-url=https://web.archive.org/web/20121103230258ec.europa.eu/research/social-sciences/pdf/14-4th-session-oliver-greefield_en.pdf |url-status=live}}
• {{citation |first1=Itsuki C. |last1=Handoh |first2=Toru |last2=Kawai |date=2011 |chapter=Bayesian Uncertainty Analysis of the Global Dynamics of Persistent Organic Pollutants: Towards Quantifying the Planetary Boundaries for Chemical Pollution” |editor1-first=K. |editor1-last=Omori |display-editors=etal |title=Interdisciplinary Studies on Environmental Chemistry—Marine Environmental Modeling & Analysis |publisher=Terrapub |pages=179–187 |chapter-url=http://www.terrapub.co.jp/onlineproceedings/ec/05/pdf/PR_05179.pdf |access-date=22 June 2011 |archive-date=27 September 2011 |archive-url=https://web.archive.org/web/20110927172415www.terrapub.co.jp/onlineproceedings/ec/05/pdf/PR_05179.pdf |url-status=live}}
• {{citation |first1=Itsuki C. |last1=Handoh |first2=Toru |last2=Kawai |title=Modelling exposure of oceanic higher trophic-level consumers to polychlorinated biphenyls: Pollution ‘hotspots’ in relation to mass mortality events of marine mammals |journal=Marine Pollution Bulletin |date=2014 |volume=85 |issue=8 |pages=824–830 |doi=10.1016/j.marpolbul.2014.06.031 |pmid=25016416 |bibcode=2014MarPB..85..824H |issn=0025-326X}}
• {{citation |first1=Janet |last1=Larsen |date=7 April 2005 |title=Plan B updates: Disappearing lakes, shrinking seas &91;web page&93; |publisher=Earth Policy Institute |place=Washington, D.C. |url=http://www.earth-policy.org/plan_b_updates/2005/update47 |access-date=13 July 2011 |archive-date=24 April 2021 |archive-url=https://web.archive.org/web/20210424170923www.earth-policy.org/plan_b_updates/2005/update47 |url-status=live}}
• {{Citation |last1=van der Leeuw |first1=S. E. |title=Climate and Society: Lessons from the Past 10,000 Years |journal=Ambio: A Journal of the Human Environment |date=2008 |volume=37 |pages=476–482 |doi=10.1579/0044-7447-37.sp14.476 |pmid=19205123 |bibcode=2008Ambio..37S.476V |s2cid=25602752}}
• NEWS, Lewis, Leo, Scientists warn of lack of vital phosphorus as biofuels raise demands, Times Online, 23 June 2008,www.foodandwatersecurity.net/data/172.pdf, dead,www.foodandwatersecurity.net/data/172.pdf," title="web.archive.org/web/20110723130701www.foodandwatersecurity.net/data/172.pdf,">web.archive.org/web/20110723130701www.foodandwatersecurity.net/data/172.pdf, 23 July 2011,
• {{Citation |last1=Lovelock |first1=J. E. |title=Gaia as seen through the atmosphere |journal=Atmospheric Environment |date=August 1972 |volume=6 |issue=8 |pages=579–580 |doi=10.1016/0004-6981(72)90076-5 |issn=1352-2310 |bibcode=1972AtmEn...6..579L}}
• JOURNAL, Lovelock, J.E., Margulis, L., 1974, Atmospheric homeostasis by and for the biosphere: the gaia hypothesis, Tellus A, 26, 1–2, 2–10, 10.3402/tellusa.v26i1-2.9731, free, 129803613, en, 1974Tell...26....2L,
• {{citation |first1=G. |last1=Mace |first2=H. |last2=Masundire |first3=J. |last3=Baillie |contribution=Biodiversity |pages=79–115 |editor1-first=R.M. |editor1-last=Hassan |editor2-first=R. |editor2-last=Scholes |editor3-first=N. |editor3-last=Ash |title=Ecosystems and human well-being: current state and trends : findings of the Condition and Trends Working Group of the Millennium Ecosystem Assessment |date=2005 |isbn=978-1-55963-228-7 |lccn=2005017196 |series=The millennium ecosystem assessment series |publisher=Island Press |url=https://books.google.com/books?id=UFVmiSAr-okC |access-date=7 November 2016 |archive-date=10 April 2017 |archive-url=https://web.archive.org/web/20170410012806books.google.com/books?id=UFVmiSAr-okC |url-status=live}}
• {{citation |ref=CITEREFMartinHenrichsothers2010 |first1=J. |last1=Martin |first2=T. |last2=Henrichs |display-authors=etal |year=2010 |title=The European environment – state and outlook 2010, Chapter 7: environmental challenges in a global context |publisher=European Environment Agency |url=http://www.eea.europa.eu/soer/synthesis/synthesis/chapter7.xhtml |access-date=7 June 2011 |archive-date=28 September 2011 |archive-url=https://web.archive.org/web/20110928201812www.eea.europa.eu/soer/synthesis/synthesis/chapter7.xhtml |url-status=live}}
• {{citation |ref=CITEREFMeadowsothers1972 |first1=D. H. |last1=Meadows |first2=D. L. |last2=Meadows |first3=J. |last3=Randers |first4=W. W. |last4=Behrens III |year=1972 |title=The Limits to Growth: a report for the Club of Rome’s project on the predicament of mankind |publisher=Universe Books |isbn=978-0-87663-165-2 |url=https://books.google.com/books?id=ulyPB2pl0SwC&q=intitle:the+intitle:limits+intitle:to+intitle:growth |access-date=7 November 2016 |archive-date=21 November 2021 |archive-url=https://web.archive.org/web/20211121224252books.google.com/books?id=ulyPB2pl0SwC&q=intitle%3Athe+intitle%3Alimits+intitle%3Ato+intitle%3Agrowth |url-status=live}}
• {{citation |first1=Toni |last1=Meier |date=2017 |title=Planetary boundaries of agriculture and nutrition – an Anthropocene approach |magazine=Proceedings of the Symposium on Communicating and Designing the Future of Food in the Anthropocene. Humboldt University Berlin, Bachmann Publisher |url=http://www.nutrition-impacts.org/media/2017_TMeier_planetary_boundaries_agriculture_nutrition.pdf |access-date=6 May 2017 |archive-date=13 September 2017 |archive-url=https://web.archive.org/web/20170913232233www.nutrition-impacts.org/media/2017_TMeier_planetary_boundaries_agriculture_nutrition.pdf |url-status=live}}
• {{citation |first1=N. I. |last1=Meyer |first2=J. S. |last2=NørgÃ¥rd |date=2010 |title=Policy Means for Sustainable Energy Scenarios (abstract) |publisher=International Conference on Energy, Environment and Health – Optimisation of Future Energy Systems |place=Denmark |pages=133–137 |url=http://www2.dmu.dk/1_om_dmu/2_afdelinger/3_atmi/ceeh/Collection%20of%20Extended%20Abstracts.pdfpage=134 |access-date=5 July 2011 |archive-url=https://web.archive.org/web/20161009062231www2.dmu.dk/1_om_dmu/2_afdelinger/3_atmi/ceeh/Collection%20of%20Extended%20Abstracts.pdfpage=134 |archive-date=9 October 2016 |url-status=dead}}
• {{citation |last1=Molden |first1=D. |title=Planetary boundaries: The devil is in the detail |department=[commentary] |journal=Nature Reports Climate Change |issue=910 |page=116 |date=2009 |volume=1 |doi=10.1038/climate.2009.97 |doi-access=free}}
• {{citation |author1-link=Mario J. Molina |last1=Molina |first1=M. J. |date=2009 |title=Planetary boundaries: Identifying abrupt change |department=[commentary] |journal=Nature Reports Climate Change |volume=1 |issue=910 |pages=115–116 |doi=10.1038/climate.2009.96 |doi-access=free}}
• JOURNAL, Neset, Tina-Simone S., Cordell, Dana, Global phosphorus scarcity: identifying synergies for a sustainable future, Journal of the Science of Food and Agriculture, 92, 1, 2–6, 2011, 10.1002/jsfa.4650, 21969145,
• {{citation |first1=M. |last1=Palaniappan |first2=P. H. |last2=Gleick |contribution=Peak Water |editor1-first=P. H. |editor1-last=Gleick |editor2-first=H. |editor2-last=Cooley |editor3-first=M. |editor3-last=Morikawa |date=2008 |title=The World’s Water 2008–2009: The Biennial Report on Freshwater Resources |publisher=Island Press |isbn=978-1-59726-505-8 |url=http://www.worldwater.org/data20082009/ch01.pdf |url-status=dead |archive-url=https://web.archive.org/web/20090320104604www.worldwater.org/data20082009/ch01.pdf |archive-date=20 March 2009}}
• {{citation |ref={{sfnref|Rockström|28 others|2009}} |display-authors=1 |last1=Rockström |first1=J |author1-link=Johan Rockström |last2=Steffen |first2=WL |author2-link=William L. Steffen |last3=Noone |first3=K |last4=Persson |first4=Ã… |last5=Chapin III |first5=FS |last6=Lambin |first6=EF |author7-link=Tim Lenton |last7=Lenton |first7=TM |last8=Scheffer |first8=M |last9=Folke |first9=C |author10-link=Hans Joachim Schellnhuber |last10=Schellnhuber |first10=HJ |last11=Nykvist |first11=B |last12=de Wit |first12=CA |last13=Hughes |first13=T |last14=van der Leeuw |first14=S |last15=Rodhe |first15=H |last16=Sörlin |first16=S |last17=Snyder |first17=PK |author18-link=Robert Costanza |last18=Costanza |first18=R |last19=Svedin |first19=U |last20=Falkenmark |first20=M |last21=Karlberg |first21=L |author22-link=Robert Corell |last22=Corell |first22=RW |last23=Fabry |first23=VJ |author24-link=James Hansen |last24=Hansen |first24=J |author25-link=Brian Walker (ecologist) |last25=Walker |first25=B |last26=Liverman |first26=D |author27-link=Katherine Richardson |last27=Richardson |first27=K |author28-link=Paul Crutzen |last28=Crutzen |first28=P |last29=Foley |first29=JA |year=2009 |title=Planetary Boundaries: Exploring the Safe Operating Space for Humanity |journal=Ecology and Society |volume=14 |issue=2 |page=32 |url=http://www.stockholmresilience.org/download/18.8615c78125078c8d3380002197/ES-2009-3180.pdf |doi=10.5751/ES-03180-140232 |doi-access=free}}
• {{Citation |author1-link=Cristián Samper |last1=Samper |first1=C. |title=Planetary boundaries: Rethinking biodiversity |department=[commentary] |journal=Nature Reports Climate Change |volume=1 |issue=910 |pages=118–119 |date=2009 |doi=10.1038/climate.2009.99 |doi-access=free}}
• {{citation |first1=R. N. |last1=Sandford |date=2009 |title=Restoring the flow : confronting the world’s water woes |publisher=Rocky Mountain Books |location=Victoria B.C |isbn=978-1-897522-52-3 |url=https://books.google.com/books?id=rtlsGsb9I4wC&q=%22Restoring+the+flow:+confronting+the+world%27s+water+woes%22&pg=PA1 |access-date=16 October 2020 |archive-date=21 November 2021 |archive-url=https://web.archive.org/web/20211121224233books.google.com/books?id=rtlsGsb9I4wC&q=%22Restoring+the+flow%3A+confronting+the+world%27s+water+woes%22&pg=PA1 |url-status=live}}
• {{Citation |author1-link=William H. Schlesinger |last1=Schlesinger |first1=W. H. |title=Planetary boundaries: Thresholds risk prolonged degradation |department=[commentary] |journal=Nature Reports Climate Change |issue=910 |page=112 |date=2009 |volume=1 |doi=10.1038/climate.2009.93 |doi-access=free}}
• {{citation |editor1-first=I. A. |editor1-last=Shiklomanov |editor2-first=J. C. |editor2-last=Rodda |title=World water resources at the beginning of the twenty-first century |publisher=Cambridge University Press |year=2003 |isbn=978-0-521-61722-2 |url=http://catdir.loc.gov/catdir/samples/cam034/2002031201.pdf |bibcode=2004wwrb.book.....S |access-date=6 July 2011 |archive-date=13 March 2012 |archive-url=https://web.archive.org/web/20120313142124catdir.loc.gov/catdir/samples/cam034/2002031201.pdf |url-status=live}}
• {{citation |last1=Steffen |first1=W. |last2=Crutzen |first2=P. J. |last3=McNeill |first3=J. R. |author2-link=Paul J. Crutzen |title=The Anthropocene: Are Humans Now Overwhelming the Great Forces of Nature |journal=Ambio: A Journal of the Human Environment |volume=36 |issue=8 |pages=614–21 |date=2007 |issn=0044-7447 |doi=10.1579/0044-7447(2007)36[614:TAAHNO]2.0.CO;2 |pmid=18240674 |hdl=1885/29029 |s2cid=16218015 |hdl-access=free}}
• {{citation |author1-link=Nicholas Stern, Baron Stern of Brentford |first1=Nicholas |last1=Stern |title=The economics of climate change : the Stern review |publisher=Cambridge University Press |date=2007 |isbn=978-0-521-70080-1 |url=http://www.hm-treasury.gov.uk/sternreview_index.htm |archive-url=http://webarchive.nationalarchives.gov.uk/20100407174731www.hm-treasury.gov.uk/sternreview_index.htm |url-status=dead |archive-date=2010-04-07}}