S P E C I A L F E AT U R E O N F R O N T I E R S I N F O OT P R I N T I N G

Letter to the Editor

Comment on “Ecological Footprint Policy?Land Use as an Environmental Indicator”

Van den Bergh and Grazi (2013) offer an assessment of eco-logical footprint accounting’s policy relevance. This importantsubject merits critical examination. Though their article con-tains many intriguing ideas, their argument is not structured toaddress the question they have raised.

In order to determine whether ecological footprint account-ing is policy relevant, at least four fundamental questions, ad-dressed in a logical sequence, must be considered first:

1. What underlying question does the footprint address?Without attending to the actual question footprint ac-counting answers, criticism easily focuses on aspects thatare unrelated to the actual question.

2. If the question the footprint addresses is clear, is thequestion relevant to policy concerns? If the underlyingquestion is clear but not relevant to the identified problemarea, then the tool is not useful.

3. If the question is relevant, are there more-accuratemethods available elsewhere for answering this partic-ular question? If so, then other tools should be used.

4. If no better methods are available, is society better offwithout the results this method generates? It could wellbe that the answers would be so poor or misleading, thatit would be better not to have any estimates at all.

Because the Van den Bergh and Grazi (2013) article ad-dresses these fundamental questions inadequately, the assess-ment remains inconclusive, as explained below question byquestion.

1. What underlying question does the footprint address?Footprint accounting attempts to answer the followingquestion: How much do people demand from ecosystemscompared to what those ecosystems (or the biosphere as awhole) can regenerate? Its purpose is to measure how bigan economy’s metabolism is compared to nature’s abilityto provide for this metabolism (Borucke et al. 2013). Vanden Bergh and Grazi’s (2013) article neither mentionsthe intent behind, nor the actual question driving, foot-print accounting. Rather, Van den Bergh and Grazi implyclaims and objectives that footprint accounting does notadvance as indicated in earlier responses to articles byVan den Bergh and his colleagues (e.g., Wackernageland Silverstein 2000).

For instance, nowhere do footprint accounts measurehypothetical hectares (ha). They are real areas. Real de-

© 2014 by Yale UniversityDOI: 10.1111/jiec.12094

Volume 18, Number 1

mand is compared to real supply. More specifically, foot-print accounts measure how many of these real areas areneeded to provide a given flow of resources and ecolog-ical services. If demand exceeds supply, a multiple of anactual, real area is needed to provide this flow. Considerthe example, “This orchard only provides half the applesthis population consumes.” This orchard is not hypothet-ical, just too small for the demand. Similarly, if timber ina forest in a given year was harvested 50% more rapidlythan timber regrew, it means that, for that year, demandcorresponded to 1.5-fold the existing biocapacity of thatforest (the difference comes from stock depletion). Thesame logic applies to the carbon footprint: There, demand(carbon emissions expressed as demand for sequestrationcapacity) is compared to dedicated sequestration capacity(forest dedicated to sequestration).1

The accounts show for the globe as a whole: Currenttotal forest capacity is smaller than the combined demandfor forest products and carbon sequestration.

Neither do footprint accounts determine whether apopulation is sustainable. Rather, footprint accounts pro-vide relevant and necessary information to sustainabil-ity assessments and identify areas of nonsustainability.Footprint accounts attempt to measure how much bio-logically productive area (i.e., biocapacity) is needed tomeet the competing demands on ecosystems, given pre-vailing technology (Borucke et al. 2013; Galli et al. 2007;Wackernagel et al. 2013). These biocapacity-adjusted ar-eas for both footprints and biocapacity are expressed in acommon measurement unit called global hectares (gha).They represent ha with world average productivity (Galliet al. 2007). In other words, 1 gha represents an equalshare of the biosphere’s regenerative capacity (approxi-mately 12 billion ha of the planet are biologically highlyproductive—hence 1 gha represents one twelve billionthof the productivity of that surface. The other 39 billionha of the Earth’s surface are only marginally productive—deep oceans, ice fields, and deserts—and are not includedin the biocapacity accounts [Borucke et al. 2013]). Thisapproach parallels financial statistics that convert differ-ent currencies into (nominal or constant) U.S. dollars,farmers who adjust calculations of available land for itsability to support cattle (expressed as “cow-calf acres”or “animal units” in rangeland management), or varioustypes of greenhouse gases (GHGs) that are convertedinto carbon dioxide (CO2) equivalents for their equiva-lent warming potential. In footprint accounts, the com-mon denominator is units of biocapacity expressed in gha.These gha are not representing potential damage, but, asmentioned above, roughly one twelve billionth of the to-tal regeneration capacity of the biosphere. This capacitycan be used to sequester CO2 or grow food or produce

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fiber or for any other nonoverlapping (competing) use ofbiocapacity.

2. If the question the footprint addresses is clear, is thequestion relevant to policy concerns? The article doesnot discuss whether the underlying question footprintaccounting pursues is relevant or not. If Van den Berghand Grazi (2013) believe it is irrelevant to know howmuch human activities demand, as compared to what thebiosphere can regenerate, they should explain why. Justas it is important for farmers to know the size of their farm,whether their farmland extends over 5,000, 500, or 5 ha,having knowledge about the productive capacity of one’sland makes a significant difference to the opportunitiesthat are available to the farmer. The same logic appliesto a region, a country, or the whole world.

3. If the footprint question is relevant, are there more-accurate methods available elsewhere for answering itsparticular question? Van den Bergh and Grazi’s (2013)article does not explain how to better measure humandemand against the biosphere’s supply, which is the mainpurpose of footprint accounts. There are other measures,but footprint accounts are unique in their ability to com-pare biocapacity supply and demand at various scales.For instance, Rockstrom and colleagues (2009) confirmglobal overshoot independently of footprint calculations,however not in a way that allows researchers to comparethe situation of each nation or put the various demandsin context with each other. Smil (2012) presents a num-ber of potential measures in a rich, information-packedbook. One is the distribution of mammalian biomass. Smilclaims in that book (and in other publications, such asSmil [2003]) that wild mammals make up less than 3% ofmammalian biomass on land, whereas the remaining 97%are made up by people and domesticated animals. Giventhat humanity, in addition to this dominance in biomass,burns significant amounts of fossil fuel, leading to a mas-sive carbon debt in the atmosphere and oceans, the 97%figure points to a striking dominance of the human en-terprise. But, by how much? Does this 97% figure alreadyindicate global overshoot? This is a question footprintaccounting answers.

Another measure Smil (2012) discusses is net primaryproductivity (NPP) assessment. He quotes one calcula-tion that concludes that 17% of global NPP is used bythe human enterprise. How does this relate to the 97%biomass figure cited above, and how close is this 17% fig-ure from a figure for maximum NPP removal? This incon-sistency stems both from the 17% number being withina large range of estimates, 10% to 50% according toRojstaczer and colleagues (2001), as well as from thedifficulty in comparing removal of NPP against a max-imum sustainable harvest rate. What to include in thecalculation of NPP production and, particularly, in NPPremoval is open to interpretation (e.g., should the rootsof the felled tree left in the ground be counted as re-moval or not? What about the ferns trampled by the for-

est workers?). In contrast, footprint accounts, which arebased on an agri- and silvacultural approach, can moresharply determine this relationship. After all, it is bothpossible and current practice to compare cubic metersof timber removed with cubic meters of timber regener-ated. Any forester can produce such estimates with rea-sonable accuracy, even using simple technology. Hence,footprint accounts offer a more reliable and robust ac-counting framework for comparing human demand onecosystems against ecosystem regeneration than NPP as-sessments are able to provide. (Granted, sometimes suchestimates get altered and misreported in official statis-tics because of economic or political interests—for in-stance, to hide illegal harvests or show fulfilled quo-tas. But, such distorted data are not a unique weaknessof footprint accounting, but affect all official statistics,including gross domestic product [GDP] or populationnumbers.)

Others (including Eurostat 2010, see, particularly,chapter 2: “Economy-wide material flows”) use mate-rial flow analysis, such as total material requirement, asan overarching metric for capturing the size of the hu-man metabolism and track overall resource efficiency.Such an assessment counts each kilogram (kg) of massmovement as equal. Of course, adding 1 kg of fossil fuelto 1 kg of gravel is possible. But, it is significantly lessmeaningful than aggregating gha because each of the gharepresents an equal share of the world’s biocapacity. Asexplained, competing demands for biocapacity can be ex-pressed in gha, including the use of 1 kg of fossil fuel or 1 kgof gravel. Further, aggregate indicators extracted frommass flow analysis, such as total material requirement,are questionable even when not compared to supply, be-cause defining a “mass flow” is ambiguous and can behighly arbitrary. What, exactly, qualifies to be includedand what not? For instance, how far does any kg of masshave to be moved in order to be counted? Should airand water be included as well? Is plowing soil movingkg of mass? Or stacking one rock on top of another one?Again, demand on ecosystem productivity, as done infootprint accounting, offers a more robust assessment ap-proach. Granted, footprint and biocapacity results can-not be computed with ultimate accuracy either (and nei-ther can GDP or GHG inventories). Footprint resultsmay have inaccuracies going into double-digit percent-age points, but, depending on how mass flows are de-fined, differences in results may be at least one order ofmagnitude.

Then, there are the monetary measures of natural cap-ital (e.g., World Bank 2011; UNEP, UNU-IHDP 2012).Financial accounts, such as the ones referenced, neitheraddress the question underlying footprint accounting norcompare demand against supply. In addition, footprint ac-counts provide a relative assessment of various demands(i.e., how much of the demand on the biosphere comesfrom food, shelter, mobility, or vice versa, and how much

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do forests, fishing grounds, or cropland contribute to theoverall capacity of the biosphere). Also, looking at thevarious demands in parallel helps to answer the followingquestion: Is the resolution of one problem just shiftingpressure onto another domain, or is the net demand onnature decreasing? Obviously, footprint accounts do notcapture the entire “problematique” of human-nature in-teractions. But, from a perspective of net demand on re-generative capacity, footprint accounts bring competingdemands on biocapacity into one overall equation, ratherthan splitting issues related to fishing, grazing, forestry,cropland, urbanization, climate change, energy, and wa-ter into silos.

4. If there are no better methods to answer the footprintquestion, is society better off without the results thismethod generates? Maybe, even if footprint critics aresatisfied with answers to the three questions above, theymay still be concerned that footprint results are exces-sively inaccurate. Therefore, footprint results need tobe tested by end users. If governments of countries be-lieve that it does matter how much biocapacity they use,compared to how much they have (i.e., they recognizethe relevance of the issue being measured by footprintaccounts—see question 2), then it is ultimately up totheir own scientific advisors to test whether the numbersgenerated are an adequate representation of their situ-ation. So far, over a dozen national government agen-cies have reviewed Global Footprint Network’s NationalFootprint Accounts (2011) for their country. Some ofthe assessment reports are available on Global FootprintNetwork’s website (www.footprintnetwork.org/reviews).For instance, the French statistical office of the Ministryof Sustainable Development independently recalculatedthe French footprint from 1961 to today. Its results werewithin 1% to 3% of Global Footprint Network’s assess-ments (SOeS 2010). So, either Van den Bergh and Grazi(2013) do not accept the relevance of the questions foot-print accounting addresses or they do but fear that theresults are so inaccurate that they would lead to curesworse than the disease. Their article is not clear on wherethey stand.

In summary, the Van den Berg and Grazi (2013) articledoes not adequately answer these four questions which deter-mine whether ecological footprint accounting is policy rele-vant and repeats previous criticism about footprint accountswithout substantiation. In response to their claims, we haveexplained elsewhere that ecological footprint accounts are nei-ther antitrade nor antitechnology, nor limited to nationalassessments, nor providing a theory of value (see frequentlyasked questions at www.footprintnetwork.org/faq, Global Foot-print Network [2009]; Wackernagel [1999]; Wackernagel andSilverstein [2000]; Wackernagel et al. [2013; forthcoming]).Footprint accounts point out trackable, economically chal-lenging mismatches between human demand and ecologicalavailability. If human demand on an ecosystem exceeds regen-eration (i.e., if there is too high pressure on existing ecosys-

tems), the ecological literature calls this “overshoot” (not “hy-pothetical land,” as termed by van den Berg and Grazi [2013]).Footprint accounts are accounts; pictures of what is, not whatcould be.

Even if Van den Berg and Grazi (2013) found the questionunderlying the footprint relevant, and the answers sufficientlyaccurate to be published, the following question still remains:Are footprint accounts policy relevant? That should be inves-tigated rigorously, but only once the footprint method passesthe test of the foundational four questions listed above, a taskthat Van den Berg and Grazi did not complete in their articleand without which their claims cannot be substantiated. But,we should also consider the opposite: Could it be that many ofour policies are not relevant to sustainability? Ultimately, wehave to determine the following: Is it a significant risk or notfor a country to run ever-larger biocapacity deficits in a world inovershoot? Will people who both earn less income than worldaverage and run biocapacity deficits in their respective coun-tries (i.e., approximately half of the current world population)be able to access sufficient biocapacity? And, if not, what couldthis mean for their wellbeing?

Note

1. Because Global Footprint Network does not have reliable globaldata documenting which exact portions of the forests are dedicatedto long-term sequestration and which ones are available to harvest-ing, its accounts have one biocapacity category for forest serving twocompeting footprint categories: forest product footprint and carbonfootprint.

Mathis WackernagelGlobal Footprint NetworkOakland, California, USA

References

Borucke, M., D. Moore, G. Cranston, K. Gracey, K. Iha, J. Larson,E. Lazarus, J. Morales, M. Wackernagel, and A. Gall. 2013. Ac-counting for demand and supply of the Biosphere’s regenerativecapacity: The National Footprint Accounts’ underlying method-ology and framework. Ecological Indicators 24: 518–533.

Eurostat. 2010. Environmental statistics and accounts in Europe. Luxem-bourg: Publications Office of the European Union.

Galli, A., J. Kitzes, P. Wermer, M. Wackernagel, V. Niccolucci, and E.Tiezzi. 2007. An exploration of the mathematics behind the eco-logical footprint. International Journal of Ecodynamics 2(4): 250–257.

Global Footprint Network. 2009. Frequently asked questions.www.footprintnetwork.org/faq. Accessed 31 August 2013.

Global Footprint Network. 2011. National Footprint Accounts—2011edition. www.footprintnetwork.org/en/index.php/GFN/page/footprint_data_and_results. Accessed 31 August 2013.

Rockstrom, R., W. Steffen, K. Noone, A. Persson, F. S. Chapin, E. F.Lambin, T. M. Lenton, et al. 2009. A safe operating space forhumanity. Nature 461(7263): 472–475.

Rojstaczer, S., S. M. Sterling, and M. N. J. Moore. 2001. Human ap-propriation of photosynthesis products. Science 294(5551): 2549–2552.

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Smil, V. 2003. The earth’s biosphere: Evolution, dynamics, and change.Cambridge, MA, USA: MIT Press.

Smil, V. 2012. Harvesting the biosphere: What we have taken from nature.Cambridge, MA: MIT Press.

SOeS (French Ministry of Sustainable Development). 2010. Une ex-pertise de l’empreinte ecologique. (January 2010, Etudes & docu-ments no. 16). [An expert review of the Ecological Footprint.]www.developpementdurable. gouv.fr/IMG/pdf/ED16_cle584d56_1_.pdf and www.developpementdurable.gouv.fr/spip.php?page=article&id_article=13526. Accessed 15 August 2013.

UNEP, UNU-IHDP (French Ministry of Sustainable Development).2012. Inclusive wealth report 2012: Measuring progress toward sus-tainability. Cambridge, UK: Cambridge University Press, UN Uni-versity.

Van den Bergh, J. C. J. M. and F. Grazi. 2013. Ecological footprint pol-icy? Land use as an environmental indicator. Journal of IndustrialEcology 18(1): 10–19.

Wackernagel, M. and J. Silverstein. 2000. Big things first: Focusingon the scale imperative with the ecological footprint. EcologicalEconomics 32(3): 341–394.

Wackernagel, M. 1999. An evaluation of the ecological footprint. Let-ter to the editor in response to “spatial sustainability, trade andindicators: An evaluation of the ecological footprint,” by J. C. J.M. van den Bergh and H. Verbruggen. Ecological Economics 31(3):317–318.

Wackernagel, M., G. Cranston, J. C. Morales, and A. Galli. 2013.Ecological footprint accounts: From research question to applica-tion. In Edward Elgar handbook for sustainable development, 2nd ed.,edited by G. Atkinson, S. Dietz, E. Neumayer, and M. Agarwala.Cheltenham, UK: Edward Elgar (forthcoming).

World Bank. 2011. The changing wealth of nations: Measuring sus-tainable development for the new millennium. Washington, DC:World Bank.

Response to Wackernagel

Both environmental science and policy are ineffective in theabsence of reliable indicators. Therefore, scrutinizing existingindicators is an important task. We are pleased that the editorinvited Wackernagel (2013) to comment on our critical article(Van den Bergh and Grazi 2013) and is allowing us to respond.

In his comment, Wackernagel opens with the statement,“Though their article contains many intriguing ideas, their ar-gument is not structured to address the question they haveraised.” We wonder what he thinks are our intriguing ideas—this alas never becomes clear from reading his comment. Thecomment about “structure” is unclear because we used a verysimple, clear structure, explaining eight shortcomings of theecological footprint (EF) followed by a discussion of its pol-icy relevance. We are disappointed that Wackernagel does notsystematically respond to our eight concerns. As we will ex-plain below, he did not respond to seven of the eight criticisms,whereas he responded in detail to only one of them. Moreover,he did not seriously engage with our arguments in the section onthe policy irrelevance of the footprint. We think that progressis only possible if the concrete shortcomings of the indicatorare discussed in sufficient detail. In the absence of a systematic

set of counterarguments to our concerns, we follow a second-best strategy, which consists of systematically responding to thearguments listed under four questions posed by Wackernagel.

1. What underlying question does the footprint address?

Wackernagel opens this point with, “Without attending tothe actual question footprint accounting answers, criticism eas-ily focuses on aspects that are unrelated to the actual question.”Is this a strategy to avoid responding to our eight concerns? Ishe suggesting that some of our criticisms are correct, but do notmatter much, for some reason?

Wackernagel says further, “For instance, nowhere do foot-print accounts measure hypothetical hectares (ha). They arereal areas. Real demand is compared to real supply.” We are sur-prised by this statement, because, in our view, it misrepresentshow the EF method works. Indeed, on the demand side, energyland is a very clear illustration of hypothetical land (becausecarbon emissions are translated into forest land); and, on thesupply side, global ha (gha; ha with world average productivity)are not concrete ha of land, but are corrected for productiv-ity differences. So, footprint accounts do report hypothetical,and not real, ha. We illustrated, in our article, one result ofthe global hypothetical ha approach: “Because productivity canchange over time, the value of a gha, as expressed in (normal)ha, is not constant.” Our conclusion was that a footprint-basedsustainability test therefore comes down to a comparison of twohypothetical, and possibly changing, quantities. This meansthat footprint studies can be confusing and difficult to inter-pret. As a result, the often-declared simplicity and clarity of theEF approach is debatable. Unfortunately, Wackernagel does notrespond to this critique on the transparency of the method.

About the carbon footprint Wackernagel says, “There, de-mand (carbon emissions expressed as demand for sequestrationcapacity) is compared to dedicated sequestration capacity (for-est dedicated to sequestration).” But, our point simply is thatcarbon sequestration can be realized in many other ways, on landand in the oceans. Focusing on carbon sequestration throughforestation is hypothetical and arbitrary as we explain carefullyin our sixth criticism on carbon sink land. Wackernagel, how-ever, does not respond to the specific arguments listed there.

Wackernagel continues with, “The accounts show for theglobe as a whole: Current total forest capacity is smaller thanthe combined demand for forest products and carbon sequestra-tion.” This denies the multifunctionality of many ecosystems.Moreover, hypothetical demand exceeding hypothetical supplytells us nothing new. Extreme rates of biodiversity loss are welldocumented, and carbon dioxide emissions are exceeding safelevels—we know that already from other indicators and associ-ated reference values, so that, in this respect, there is no needfor EF accounting. Translating greenhouse gas (GHG) emis-sions in forest land does not help to improve our understandingof the problem of global warming or to enhance climate policymaking.

Wackernagel further claims, “Neither do footprint ac-counts determine whether a population is sustainable. Rather,

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footprint accounts provide relevant and necessary infor-mation to sustainability assessments and identify areas ofnonsustainability.” But, these statements do not seem to beconsistent, because sustainability assessments for cities, regions,or countries do imply a statement about whether the associatedpopulations are sustainable (if only because the total footprintis the sum of the individual footprints of people in the popu-lation). Moreover, Wackernagel does not respond clearly to amajor critique of our article, namely, that drawing conclusionson the (un)sustainability of human activities based on an over-simplified, nontransparent method as is the footprint is, at best,irrelevant to policy making, if not misleading.

2. If the question the footprint addresses is clear, is thequestion relevant to policy concerns?

Because Wackernagel does not say much on this secondquestion, we are equally short. We believe it is relevant to exam-ine whether we are overusing certain environmental capacities.So, we believe in concrete indicators, comparing demand forspecific metals, energy, and water resources with their knownsupply. And, of course, it is useful and necessary to compareGHG emissions and concentrations with safe levels, as climatescientists do. Yet, we do not believe it is relevant to aggregatesuch distinct environmental issues, such as GHG emissions,timber use, food production, and others, in one hypotheticalland indicator, as if everything can be reduced to land. Wediscussed the specific problems of this, among others, in thethird criticism on “land value theory.” Wackernagel simplifiesour view as that we “believe it is irrelevant to know how muchhuman activities demand as compared to what the biospherecan regenerate.” We simply do not believe, as he does, that thiscomparison is useful at a very aggregate level.

3. If the question is relevant, are there more accuratemethods available elsewhere for answering this partic-ular question?

The argumentation of Wackernagel under this item remindsus of a frequent defense to criticism of the gross domestic product(GDP; per capita) as an indicator of social welfare or progress(Van den Bergh 2009): if there is no better indicator, whichis comparable for all countries, then we should not get rid ofthe old imperfect one. However, we believe that we shouldstop using the GDP (per capita) to measure progress, regard-less of whether other (better) macro indicators of progress are(already) available, that is, calculated regularly for all countriesin a comparable way (Van den Bergh 2010). Similarly, if thecritique of the EF is valid, then one should not use it or changeits method of calculation, even if there are no other indicatorsthat measure approximately the same thing.

Wackernagel says, “Van den Bergh and Grazi’s article doesnot explain how to better measure human demand against thebiosphere’s supply, which is the main purpose of footprint ac-counts.” Are we really obliged to do this? Can we not criticizean indicator without offering an alternative? Does the absenceof such an alternative make the critique valueless? As explained

already under question 2 above, we are not convinced it is nec-essary or useful to undertake this measurement at the aggregatelevel. Instead, we would urge Wackernagel to take our criti-cisms seriously and strive to alter the footprint method so as toaddress them.

Wackernagel continues: “For instance, Rockstrom andcolleagues (2009) confirm global overshoot independently offootprint calculations, however not in a way that allows re-searchers to compare the situation of each nation or put thevarious demands in context with each other.” One can see thecountry dimension and the comparability of countries perhapsas an advantage of the footprint, but one should add that thecountry rankings of the per capita EF or ecological deficit arevery dubious because they depend on many assumptions and un-reliable data and, as a result, are not robust. The rankings are,however, what make the footprint so popular. The problem isthat the rankings are the least trustworthy part of the footprintoutput because they are very sensitive to the various assump-tions made. The global overshooting message is credible, but notsurprising, because we have already so many indications for itbased on more-concrete indicators of global warming, biodiver-sity loss, ocean acidification, freshwater scarcity, interferencewith nitrogen and phosphor cycles, and so on. The footprintdoes not even aggregate all these important problems and, forthe problems that it aggregates, does not justify the implicitaggregation weights used.

Wackernagel’s criticism of the approaches by Rockstrom andcolleagues, Smil, Eurostat, and Worldbank/UNEP (a bit of anarbitrary selection in our view) does not make the EF moreconvincing. Why did Wackernagel, in fact, use so much spaceand text in his comment to discuss these instead of respond-ing systematically and in detail to the arguments under eachof our eight criticisms? This would surely have resulted in amore productive scientific debate. We do not feel obliged todefend the above-mentioned researchers and reports becausethey are irrelevant to (do not affect) our criticisms. In fact, re-garding Wackernagel’s cynicism about Eurostat (chapter 2) on“Economy-wide material flows,” where each kilogram of massmovement is counted as equal, we fully agree that the “equalweights” approach (common in material input per unit of ser-vice and total material requirement indicators; e.g., Bringezuet al. 2004) to materials as diverse as sand, gravel, toxic metals,plastics, and fuels is indefensible from an environmental per-spective. Wackernagel should realize, nevertheless, that withthis criticism he is on slippery ground because the footprintmethod equally uses debatable implicit weights. We discuss thisin detail in our article’s fifth criticism on “Aggregation throughunfounded, implicit weights.”

4. If not, is society better off without the results thismethod generates?

Wackernagel says here, “If governments of countries believethat it does matter how much biocapacity they use, compared tohow much they have . . . , then it is ultimately up to their ownscientific advisors to test whether the numbers generated are an

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adequate representation of their situation.” The reality, though,is that few governments and statistical offices are interested,because the policy relevance of the footprint information islow. Wackernagel formulates it differently: “So far, over a dozennational government agencies have reviewed Global FootprintNetwork’s National Footprint Accounts (2011) for their coun-try.” Note here the diplomatic use of the term “reviewed.” It is abit like saying, “Top journals have reviewed my paper” withoutindicating that they accepted or rejected it.

We argue the policy irrelevance of the footprint extensivelyin our article’s last section, but Wackernagel, regrettably, doesnot systematically respond to our arguments. The only thingWackernagel says is, “So, either Van den Bergh and Grazi(2013) do not accept the relevance of the questions footprintaccounting addresses or they do but fear that the results areso inaccurate that they would lead to cures worse than thedisease.” We think our article is clear on both issues. The foot-print does not address policy-relevant questions in our view: Assaid, overshooting in several environmental dimensions is clearfrom many other, better interpretable indicators; the countryrankings are debatable; and the footprint does not provide anyspecific information for deciding about concrete policies. Asopposed, information about, for instance, GHG or acidifyingemissions can be directly linked to safe concentrations andeffective policy standards.

We are surprised that Wackernagel ends with, “the followingquestion still remains: Are they policy relevant? That should beinvestigated rigorously, but only once the footprint methodpasses the test of the foundational four questions listed above,a task that Van den Bergh and Grazi did not complete in theirarticle and without which their claims cannot be substantiated.”The truth is that we devoted an entire section on this with clearsubquestions, we scrutinized the policy relevance of particularoutputs of the footprint approach (ecological deficit, regionalfootprint, and so on), we reviewed various footprint studies fortheir policy insights, and so on . How can Wackernagel honestlysuggest that we did not address the policy relevance thoroughly?His response to this point is not so much unfair as disappointing.

Wrapping up

We presented eight concerns about the ecological footprintmethod:

1. False concreteness2. Global hectares: Adding to the hypothetical character of

the ecological footprint3. A case of “land value theory”: Land use as a proxy of

environmental pressure

4. Incompleteness in terms of capturing relevant environ-mental pressures

5. Aggregation through unfounded, implicit weights6. Carbon sink land resulting from an arbitrary “sustainable

energy scenario”7. Countries versus “bioregions”8. Ecological deficit and antitrade sentiments

Wackernagel did not respond at all to our arguments underconcerns 1, 3, 4, 5, 6, and 7 and neither to the section on pol-icy irrelevance. He did defend the arguments under concern 2.Here, our main point remains unrefuted, namely, that gha donot contribute to transparency because not only demand, butalso supply of land has become hypothetical and unreal. Finally,regarding concern 8, Wackernagel just states in one sentence,without any argumentation, that the footprint is not antitrade,whereas he did not go into any of our specific arguments, eventhough we devoted an entire separate section on these. So,despite a fairly long reply, Wackernagel merely responded se-riously to one of eight criticisms. We leave it to the reader tointerpret this conclusion.

Jeroen C.J.M. van den BerghICREA, Barcelona, SpainInstitute for Environmental Science andTechnology, Universitat Autonoma de Barcelona, Spain& VU University Amsterdam, The Netherlands

Fabio GraziAgence Francaise de Developpement (AFD)Paris, France

References

Bringezu, S., H. Schutz, S. Steger, and J. Baudisch. 2004. Internationalcomparison of resource use and its relation to economic growth:The development of total material requirement, direct materialinputs and hidden flows and the structure of TMR. EcologicalEconomics 51(1–2): 97–124.

Van den Bergh, J. C. J. M. 2009. The GDP paradox. Journal of EconomicPsychology 30(2): 117–135.

Van den Bergh, J. C. J. M. 2010. Relax about GDP growth: Implicationsfor climate and crisis policies. Journal of Cleaner Production 18(6):540–543.

Van den Bergh, J. C. J. M. and F. Grazi. 2013. Ecological footprint pol-icy? Land use as an environmental indicator. Journal of IndustrialEcology 18(1): 10–19.

Wackernagel, M. 2013. Comment on “Ecological footprint policy?Land use as an environmental indicator.” Journal of IndustrialEcology 18(1): 20–23.

Letters to the editor commenting on articles published in the Journal of Industrial Ecology are considered for inclusion inthe Journal based on relevance and availability of space. To submit a letter for consideration, visit the Journal’s Web-basedsubmission site at http://mc.manuscriptcentral.com/jie. Letters should be brief and replies from the authors of the article underdiscussion will be invited. Length and content are subject to review by the editors.

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