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1 QUESTIONING THE ECOLOGICAL FOOTPRINT 2 3 Alessandro Galli1, Mario Giampietro2, Steve Goldfinger3, Elias Lazarus4, David Lin5, Andrea 4 Saltelli6, Mathis Wackernagel7, Felix Müller#8 5 6 ABSTRACT 7 In this perspective paper a critical discussion about the concept of the Ecological Footprint is 8 documented based on 10 questions which are answered from critical and supporting points-of- 9 view. These key questions are directed towards the underlying research objectives of the 10 approach, a comparison with similar concepts, the quantification methodology and its accuracy, 11 the characteristics of the observed flows, the role of scales and resolutions, the implementation 12 of security, the utility of the ecological footprint for society, the political relevance of the 13 concept and the differences from other international indicator systems. 14 15 KEY WORDS 16 Footprint relevance, footprint methodology, footprint applicability, footprint utility, footprint 17 critics 18 19 HIGHLIGHTS 20  10 key questions concerning the Ecological Footprint are asked 21  The questions are answered from a critical and a supporting viewpoint 22  Overall, discussion and clarity regarding indicators and their representation of 23 is needed and should be continued 24

1 , 7-9 Chemin de Balexert, 1219 Geneva, . Tel.+39-346-6760884, E-mail: [email protected] 2 Institució Catalana de Recerca i Estudis Avançats (ICREA), ICTA-UAB and Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona (ICTA-UAB), E-mail: [email protected] 3 Global Footprint Network, 312 Clay Street, Suite 300, Oakland, CA 94607-3510, USA, E-mail: [email protected] 4 Global Footprint Network, 312 Clay Street, Suite 300, Oakland, CA 94607-3510, USA, Tel. +1-510-839-8879, E- mail: [email protected] 5 Global Footprint Network, 312 Clay Street, Suite 300, Oakland, CA 94607-3510, USA, Tel. +1-510-839-8879, E- mail: [email protected] 6 Centre for the Study of the Sciences and the Humanities (SVT) - University of Bergen (UIB); Institut de Ciència i Tecnologia Ambientals (ICTA) -Universitat Autonoma de Barcelona (UAB),E-mail: [email protected] 7 Global Footprint Network, 312 Clay Street, Suite 300, Oakland, CA 94607-3510, USA, Tel. +1-510-839-8879, E- mail: [email protected] 8 Institute for Natural Conservation, University of Kiel, Olshausenstrasse 75, D 24118 Kiel, Germany.Tel. +49431-8803251, E-mail: fmueller@.uni-kiel.de # corresponding author 1

25 INTRODUCTION 26 Scientific debates are focal elements of progress in research and development of academic 27 conceptions and methodologies. According to the strong epistemological tradition which 28 demarcates science from other endeavors, the capacity to progress by successive refutations 29 and rectifications is a focal element of scientific discussions. Although they are sometimes 30 executed in an obstinate and less tolerant atmosphere, the outcome can be a productive “cross 31 fertilization”, opening the objects of research for new aspects, setting new questions, 32 demanding for adapted concepts and targets and widening the knowledge in the respective 33 field of science. 34 Indicators provide aggregated and simplified information on phenomena which often are hardly 35 directly determinable, and as such they are suitable objects of intensive debates: Their 36 definitions, the relations to the indicandum, the elaborated methodology and its transparency, 37 the respective measurements and collections, the produced results and their interpretations 38 are often related with certain inaccuracies and uncertainties. Furthermore, the contextual 39 extents of indicators as well as their degrees of aggregation provide a wide field of problems, 40 challenges, potential ambiguities, normative loadings and, consequently severe discussions. 41 In the following, unusual article, a hopefully constructive step in the scientific debate about the 42 Ecological Footprint is made: The paper is based on the exchange of several letters, replies and 43 articles in which conceptual and methodological aspects of the Ecological Footprint have been 44 discussed in this journal (see Giampietro and Saltelli 2014 a, b, Goldfinger et al. 2014, Lin et al. 45 2015 and additionally van den Bergh and Grazi 2015). To avoid a long-term sequence of papers 46 the authors agreed to produce this joint perspective article. It aims to shed light on the roots of 47 ongoing critical discussions regarding the Ecological Footprint and its methodology. This has 48 been boiled down to ten key questions by which we identify strengths and limitations of the 49 Ecological Footprint from different perspectives. Therefore, in this article the authors do not 50 agree with the overall contents; In the opposite, the paper is documenting basic disagreements. 51 One perspective is offered by Mario Giampietro and Andrea Saltelli. The other perspective is 52 presented by researchers associated with Global Footprint Network: David Lin, Mathis 53 Wackernagel, Alessandro Galli, Elias Lazarus, and Steve Goldfinger. Both parties suggested five 54 questions each to frame the discussion about the validity and the utility of Ecological Footprint 55 accounting. Each perspective is offering their particular answers for all 10 questions. 56 This paper starts from a common point of departure. Both parties recognize that it is 57 fundamental for policy formulation and monitoring to have a quantitative approach capable of 58 measuring human demand on nature against nature’s ability to provide ecological services. The 59 position of Global Footprint Network is that Ecological Footprint Accounting adds up ecological 60 services people demand in as far as they compete for biologically productive space9. According 61 to this claim the Ecological Footprint can be compared against the available bioproductive area 62 which provides these services - for short (Borucke et al. 2013). Giampietro and 63 Saltelli, on the contrary, argue that the claim of Global Footprint Network does not stand 64 scrutiny (Giampietro and Saltelli, 2014 a, b) and that the Ecological Footprint is not a

9 For an introduction of the footprint methodology, see e.g. Borucke et al. (2013) and Wackernagel et al. (2014) 2

65 quantitative approach capable of measuring human demand on nature against nature’s ability 66 to provide ecological services, and that the results generated by this methodology are not 67 useful. This divergence of opinions led to the present paper. 68 69 The differences between the basic attitudes of the co-authors are already visible by focusing on 70 the basic definitions: 71 72 The Footprint Network provides the following terminology: Ecological Footprint accounting 73 answers the question: How much of the regenerative capacity of the is occupied by 74 human demand? Humanity’s Ecological Footprint is the sum of all biologically productive 75 surfaces of the planet for which all the human demands compete. These biologically productive 76 surfaces renew , provide services such as carbon sequestration, or accommodate 77 urban infrastructure. Human demand can be a single activity, the of one person, a 78 , a country or humanity as a whole. Ecological Footprints, or human demand (in a given 79 year) is compared to the amount of resources and services that are generated by the 80 biologically productive surfaces of the planet or a region (in that given year) – the biocapacity. 81 Both biocapacity and Ecological Footprint are measured in hectare-equivalent units, namely 82 global hectares. These are biologically productive hectares with world average . 83 Note that not only the Ecological Footprint but also biocapacity changes over time with shifting 84 climate conditions, soil quality and management practice. As a consequence, the value of a 85 also changes from year to year. Hence results are presented in constant global 86 hectares, i.e., the value of a global hectare in a given year. 87 88 At the other side, Giampietro and Saltelli comment on the basic term of biocapacity with the 89 following paragraph: What is called “biocapacity” in Ecological Footprint Accounting is better 90 described as “agricultural productivity”. It measures actual yields of per hectare that 91 are due to human manipulation of ecological processes (with no consideration for the damage 92 to the environment) and massive injections of fossil based inputs (entailing the 93 depletion of a non-renewable stock). Therefore, what is measured in the Ecological Footprint 94 protocol under the label “biocapacity” is not an assessment of how much can be produced on 95 this planet according to its ecological limits. 96 97 Basing upon these general contradictions, both parties suggested five questions each to frame 98 the discussion about the validity and the utility of Ecological Footprint accounting. Both parties 99 have answered all questions. 100 101 102 103 104 105 106 107

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108 KEY QUESTIONS

1. What underlying research question does the Ecological Footprint address?10

Giampietro and Saltelli Lin, Wackernagel, Galli Goldfinger, and Lazarus The mathematical protocol developed by the Ecological Footprint accounting addresses Global Footprint Network (GFN) aims to one key question: How much of the assess man’s impact on the planet and biosphere’s regenerative capacity do human wishes to achieve this by aggregating across activities demand? This measure can then be scales and compartments, while at the same compared to the biosphere’s available time focusing on a subset of the relevant regenerative capacity. By doing so, the dimensions of man’s impact. Thus the Ecological Footprint framework accounts for measures arrived at by the Global Footprint 1) the magnitude of humanity’s physical Network - the quantitative assessments metabolism and 2) the demand such labeled as “Ecological Footprint” and metabolism places on the ’s “Biocapacity” - have a purported . Thus, it captures a necessary, resemblance with the regenerative and but not sufficient, condition for sustainability. absorptive capacity of the biosphere but no descriptive power. The Ecological Footprint framework is not a measure of total human impact but a proxy A research question on man’s impact on the for human pressure on ecosystems. planet is asked and left unanswered, while a full metaphorical apparatus is developed to In concept, the Ecological Footprint is the communicate the result of this analysis as an sum of services used by humans, overall measure of man’s impact, such as the to the extent that these services occupy ‘Earth Day’. Stating that ‘August mutually exclusive, biologically productive 13 is 2015’ area. These services include provision of (www.overshootday.org), and that in less resources, housing, infrastructure, and than 8 months, Humanity exhausts Earth's absorption of that ’s waste, using budget for the year is a clear answer to the prevailing technology and management question of man’s overall impact on the practices (Wackernagel, 1991; Rees and planet, but this number, precise to eight Wackernagel, 1994; Wackernagel and Rees, digits, is a misleading – an in a sense 1996; Wackernagel et al., 2002). In current reassuring - non-being. Depending on what National Footprint Accounts (NFA), direct dimension of possibly irreversible impact of tracking of waste flows is limited to CO2. man on the planet is looked at this number By tracking and adding up human demands could refer to a day located decades in the competing for biologically productive space, past (see answer 4). Ecological Footprint accounts incorporate both of Daly’s sustainability principles (Daly, 1990) which stipulate that within a closed system, the harvest rate should not exceed

10 Question formulated by the Footprint Network 4

the regeneration rate and the waste production rate should not exceed the rate of assimilation.

2. How is the research question underlying the Ecological Footprint relevant or irrelevant to policy concerns?11

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus When it comes to policy concern, one should If we are to live within the ecological bear in mind: (i) “make everything as simple constraints of our planet, keeping track of as possible but not simpler” (Albert Einstein); the biophysical size of an economy – and (ii) “all models are wrong, but some are particularly compared to the size of useful” (George E.P. Box). Our criticism of supporting ecosystems – enhances effective the Ecological Footprint protocol moves from policy development (Bullock, Mountford, and a critique of its implausible simplifications Stanley 2001). (e.g., for energy security the only biocapacity taken into account is land absorbing CO2) to Assuming that human society cannot take address the inadequacy of the construct to more than the biosphere can renew without deal with the relevant subject matter. The endangering its stability, any policy we questions addressed by the Ecological implement should consider whether it Footprint are relevant but the answers deepens or alleviates society’s resource misleading (e.g., increasing ecosystem dependence. Also, it may make sense for alteration is deemed positive for each society to set explicit goals about how biocapacity). When dealing with policy much its economy should use compared to concern, the combination of being relevant what ecosystems can renew. and scientifically wrong is unfortunate. While most governments have not yet The extraordinary success of the Ecological committed to meaningful and effective Footprint, its take up by a myriad of policies on consumption and resource countries and well-intended organizations, efficiency, Ecological Footprint accounting and its frantic consumption by the media, has been incorporated into official initiatives raise deep concerns on the internal system of at least 12 national governments or of quality control of science – which is today intergovernmental agencies (e.g., Giljum et in a status of deep crisis (Lancet 2015, al. 2007, SENPLADES 2010). It has been used Nature 2015, Ioannidis 2014). As of today to set targets and to guide major shifts in only a handful of practitioners have moved budgeting, sustainable investments, and to context the veracity of the Ecological policy (Whitby et al. 2014). Businesses and

11 Question formulated by the Footprint Network

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Footprint (see recent reviews in Blomqvist et financial institutions have applied it, such as al. 2013 and van den Bergh and Grazi 2015), in the World Business Council for Sustainable and these critics have never reached neither Development’s Vision 2050 Project. the top mainstream scientific journals nor Additionally, civil organizations, such as the the media. World Wide Fund for Nature International (WWF), use the Ecological Footprint accounts to represent human demand on natural systems.

3. If the research question underlying the Ecological Footprint has some relevance, are there more accurate methods available for answering this particular question?12

Giampietro andSaltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus Yes: Given the acknowledged lack of other * (Rockström et al. comprehensive metrics in this domain, and 2009a; 2009b; Cornell 2012; Wijkman and the fact that Ecological Footprint accounts Rockström, 2012; have been reviewed and validated by nearly http://www.stockholmresilience.org/21/rese a dozen government studies, these accounts arch/research-programmes/planetary- represent, in our view, the best available boundaries.html) systemic approximation of a human *Nature Index (Pedersen et al. 2013; Certain population’s demand on nature. et al. 2011 ; 2013), that can be integrated into the UN System of Environmental- A unique feature of Ecological Footprint Economic Accounting; accounting is its ability to assess the size of http://unstats.un.org/unsd/envaccounting/s the human enterprise against Earth’s eea.asp biological capacity, even over time. *Ecological indicators from , such as EMergy analysis (Odum, Complementary approaches exist, which 1996; Brown and Ulgiati, 2004), confirm the risks of (see for aquatic ecosystems (Ulanowicz, 1996; also question 9). Planetary Boundaries Patricio et al. 2006), Ecosystem Integrity (Rockström et al. 2009, Steffen et al. 2015), (Guntenspergen 2014, Kay et al. 2001); for example, identify overuse in specific *MuSIASEM to study the nexus between domains. However they do not provide an energy, food, and land uses in socio- overall assessment of the ratio between ecological systems and its relation to human demand and earth’s regenerative environmental impact (Giampietro et al. ability, nor show how this relationship 2012; 2014; Madrid et al. 2013). changes over time, or show the regional distribution of overuse. The fact that none of the above methods

12 Question formulated by the Footprint Network

6 offer the perfect tool to measure human Other approaches measure demand but are demand on nature against nature’s not able to identify limits. For example, the regenerative ability does not imply that the World Bank’s monetary Ecological Footprint has comparable assessment provides a relative value of legitimacy and quality. In its insistence to natural capital compared to other capital, but capture the big picture with just one number does not indicate whether the amount of the Ecological Footprint puts itself at odds natural capital is sufficient. Similarly, Material with the of scientists concerned Flow Assessments track the weight of with a responsible use of quantitative material flows, but this is not compared information in . against any regeneration rate.

4. Given the quality and accuracy limitations of current Ecological Footprint results, is society better off without these results?13

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus The results provided by the ecological The National Footprint Accounts, the main footprint are misleading and may result in application of Ecological Footprint harmful policies. According to the Ecological accounting, uses the standard international Footprint protocol replacing natural datasets and operates under the assumption ecosystems with more productive human- that people would be better off with managed vegetation would increase the decisions fully informed by available biocapacity of our planet. The Ecological empirical evidence of the biocapacity Footprint protocol suggests we are situation. Despite representing a overshooting the of the conservative estimate of human demand on planet by a mere 50%, but the quantity of nature, current global and national accounts nitrogen used in agriculture alone would document significant biocapacity deficits (see already require 2.5 planets to be fixed by Galli et al., 2014). If the Ecological Footprint natural processes (let alone the generation truly is an underestimate, the implications of other valuable flows or the absorption of suggest that contracting the human harmful pollutants.) metabolism is necessary, and economic development strategies consistent with this The Ecological Footprint does not address material need should be adopted. Rejecting the requirement of sink capacity for these results and continuing on current pollutants nor the supply capacity for liquid working assumptions, which largely ignore fuels. physical constraints, would make humanity worse off. Other serious flaws have been pointed out in the journal PLoS Biology by Blomqvist et al., Given that conservative results from the 2013 and by many others (for an overview National Footprint Accounts (NFA) represent

13 Question formulated by the Footprint Network

7 see van den Bergh, and Grazi, 2015). a minimum necessary condition, one could argue that sustainability policies based on current Ecological Footprint numbers may not be aggressive enough. However, current sustainability policies remain insufficient to address resource limitations and trends highlighted by Ecological Footprint accounts.

For a detailed explanation on specific examples such as replacement of natural ecosystems with human managed systems such as cropland, and why this does not necessarily increase biocapacity, see Goldfinger et al. (2014).

5. What are the external referents used for quantitative assessments in Ecological Footprint Accounting and what is the accuracy of the measurement schemes used to quantify their relevant characteristics?14

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus This question is not a philosophical but The majority of data used in the Footprint technical one. Before undertaking any accounts refers to annual produced measurement, two pieces of information are quantities (tonnes per year), annual needed: (i) expected characteristics of what productivity (tonnes per hectare per year) has to be measured; and (ii) the accuracy of and areas harvested/used for production of a the measurement scheme. If we want to given year (hectares) as reported by the UN. measure the height of a human being, we Currently, we cannot comprehensively assess must be able to (i) recognize an instance of the precision and accuracy of data compiled human being, i.e. what we want to measure; by UN statistics. Therefore, current National something with a height of 30 m (e.g., a Footprint Accounts calculate results under statue) is not a human being even if it looks the assumption that these data sources are like one; and (ii) use a meter with an reliable. However, discrepancies in trade admissible accuracy. An accuracy of ± 3 m is statistics allow us to compare the degree to good for measuring the length of highways which a country’s trade reporting matches its but not for measuring the height of human partners reporting for what should be beings. What are the “expected identical transactions. These discrepancies characteristics” of the specific processes give insight into potential noise in the data generating biocapacity that are measured by set. the Ecological Footprint? What is the error

14 Question formulated by Giampietro and Saltelli

8 bar on the measurement of biocapacity Significant difficulty remains in assessing the expressed in global hectare equivalent? quality of input data; however verification reports have been performed by the national Is the accuracy of the assessment the same agencies (e.g., statistical bureaus) of several at the local, national and global level? countries (e.g., France, Switzerland, Japan, and Luxembourg). In France, for example, the The implications of these questions become independent re-running of the national clear in the answer to the next question 6. Footprint calculation with locally-sourced data has yielded results consistent with those generated by Global Footprint Network (1-4% difference). Additional assessments of NFA results continue to generate insights into potential improvement of the accounts. This includes moving towards reconciling balance-based NFAs with Multi-Regional Input-Output (MRIO), possibly leading to hybrid-MRIO based Footprint calculations (Weinzettel et al. 2014). Researchers are also refining the calculation (Mancini et al., 2015).

6. When calculating Ecological Footprint and Biocapacity, is the measurement referring to the characteristics of a typology (which typology?) or to the characteristics of an instance? (An instance of what?)15

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus We answer this question with a metaphor Ecological Footprint and biocapacity accounts about how to account for the biocapacity of measure bioproductivity expressed as the a flow. Let’s imagine one wants to calculate amount of global bioproductive area needed the “bio-capacity” required to obtain 1,000 to supply a basket of services. The National liters of milk measured not in hectares but in Footprint Accounts use input data number of cow-day equivalents. Let’s aggregated by year, and therefore are a time assume that at world level there are three series record (1961-2011) of annual flows ways to supply milk: (A) producing 6-15 (Ecological Footprint and biocapacity). liters/day per cow in production (to be Biocapacity can change with environmental reduced because of cow-days not in and managerial conditions and reflects production); (B) producing 20-40 liters/day current conditions as opposed to a per cow in production (ditto); (C) stock theoretical productivity in the absence of

15 Question formulated by Giampietro and Saltelli

9 depletion (using stocks of long-conservation human influence. milk). Imagine to measure in a given year (2014) (i) the liters of milk supply in the Biocapacity accounts start with actual land world (590 billion = total liters); and (ii) the areas (ha), which are then weighted by their number of cow-days producing milk in the relative global bioproductivity (global world (95 billion = total cow-days). The hectares). Footprint accounts start with resulting ratio, 6 liters/cow-day, reflects the material flows such as cereals, vegetables, particular situation in 2014 given by the milk, wood, CO2 emissions, etc. Then the relative importance of the three typologies amount of actual land area needed to A, B and C in providing the total supply, but generate these flows is calculated. Just as does not provide an assessment of the with biocapacity, these areas are expressed “biocapacity” (expected characteristics of in a common measurement unit, global physical processes) required to produce hectares. This is done by calculating the area, 1,000 liters of milk. An assessment of 166.7 at world average productivity, needed to cow-days required for producing 1,000 liters generate these flows. Stocks are not tracked of milk does reflect what happened in the by Footprint accounts. year 2014 (an instance) but will not provide any information about the required For example, the calculation of the Ecological “biocapacity” for producing 1,000 liters of Footprint (or biocapacity requirement) of milk on our planet in a sustainable way. An milk in 2014 starts with milk produced in assessment of “biocapacity” would require a 2014 (not stocks). Using the production flow, prior definition of the characteristics of the we then calculate the total amount of elements producing the flow. These equivalent bioproductive land required for characteristics determine their capacity to the production of this milk. The Footprint of produce the flow in a sustainable way. This milk is spread across grazing land (to provide point is discussed in the next answer. food for milk-animals), cropland (again to provide food for milk-animals), built-up land (to provide supporting infrastructure), and forest land (to sequester CO2 emitted through electricity and fossil fuel use during the production process). For the consumption Footprint, we add to this production number the import and subtract the exports.

7. Ecological Footprint Accounting methodology generates a unique set of quantitative assessments obtained combining together measurements referring to processes taking place at different scales. This unique set of quantitative assessments is supposed to be equally useful for agents operating at different

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scales – e.g. farms, , provinces, nations, macro-regions, and the planet. What are the main benefits and the main limitations of this approach?16

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus The Ecological Footprint protocol is Ecological Footprint accounting provides a measuring flows without making a framework for organizing information. At distinction among different typologies of each spatial scale, whether global, national, elements producing the flows. Using the individual, or a single activity, appropriate metaphor of milk production described in data for these accounts is required. Simmons the previous question 6 we distinguish: et al. (2000) describe two methods to derive NFAs. The first approach follows a bottom-up Type A: flow in steady-state based on natural approach and attempts to account a processes. Cows producing milk without complete set of consumed items, and drugs with a life expectancy of over 15 years determines the Ecological Footprint of each are the external referents to be used to of these using Life Cycle Assessment (LCA). measure natural biocapacity; Accuracy here depends on the completeness of the set, and the accuracy of the individual Type B: flow determined by human LCAs. Given a robust set of input data, this technology powered by non-renewable method can be reasonably accurate and is resources. Cows forced to produce more generally better suited for high-resolution milk with hormones and fossil-energy based specific accounts, such as those at the unhealthy diets should not be included in individual or activity level, but suffers from measurements of natural biocapacity; data availability at larger scales.

Type C : non-renewable flow. Depleting Global Footprint Network uses a second stocks of long-conservation milk has nothing method to produce the NFAs. This method is to do with biocapacity. a top-down approach which uses national aggregate input data on production, trade Summing indiscriminately the different flows, and consumption. (For a full listing of sources of milk and cows-days in 2014 inputs, see Kitzes et al. 2009). For practical generates a number that is completely implementation, regional or world average useless for policy. The resulting value of 6 data is substituted when country specific liters per cow-day does not provide any data is not available. The accuracy and relevant information for individual dairy reliability of accounts following this method farmers (when deciding how to produce are highest at global level and in countries milk: type A or B?), regional governments with robust national statistics. For finer scale regulating milk production, or national accounts such as those of a province, either governments making scenarios of the appropriate province level data is required or environmental impact of milk production. lower resolution national data must be scaled down. The latter would result in decreased

16 Question formulated by Giampietro and Saltelli

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Moving out of the metaphor of milk accuracy. production, an increase in land productivity in agriculture based on the massive For end users, it can be useful to track depletion of “long conservation stocks of Footprint accounts through time and in fossil energy” should not be interpreted as different spatial contexts, from household to an increase in ecological biocapacity. global. Following the principles listed in answer 1, heads of a household may make All sums elaborated by the Ecological decisions based on a particular biocapacity Footprint system of accounting are obtained budget, just as a city or a nation could. by mixing together characteristics of instances belonging to different typologies (liters of milk from cows of Type A, Type B and from stocks), without even specifying the relative size of these instances in the mix.

8. Ecological Footprint Accounting measures the biocapacity required for energy security as the land requirement required to absorb the CO2 emissions. But then why does it not adopt the same logic for calculating the biocapacity required for – e.g. measuring the land required to absorb human dejections and food waste – rather than the land required to produce food?17

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus As explained by Georgescu-Roegen (1975) Ecological Footprint accounts do not, nor are (building on the work of Lotka and Odum) a they intended to measure energy security. society metabolizes matter and energy in Neither do they track stocks (such as the two different forms: (i) endosomatic flows – availability of fossil fuels). They only look at nutrients contained in food metabolized the demand for the annual capacity to inside the human body; (ii) exosomatic flows produce renewable resources and assimilate – energy carriers and minerals metabolized waste. This logic is followed consistently for and transformed under human control but CO2, food waste, or human dejections. outside the human body. This second metabolism requires the use of technology In the case of CO2, this service is waste (exosomatic devices). Both types of assimilation. It is a competing demand on metabolism require biocapacity for the biocapacity and therefore can be added up to supply of the input flows (to produce other demands. Also, to meet the minimum eaten by the population and to produce condition for sustainability in a closed energy carriers and materials used by system, in any given year waste should not society) and for the sink-capacity of waste be produced faster than it is assimilated. Ecological Footprint accounting therefore

17 Question formulated by Giampietro and Saltelli

12 flows (to absorb dejections and emissions). considers fossil fuel only from the perspective of its demand on waste However, when dealing with the stability of assimilation capacity (one aspect of the endosomatic metabolism (the requirement overall biocapacity). of food) the Ecological Footprint protocol measures the requirement of biocapacity by The demand on nature imposed by waste looking only at the supply side (land required food and human dejections is not discretely for agricultural production). On the contrary tracked by the Ecological Footprint, but is when dealing with the stability of the captured within two components of the exosomatic metabolism (the requirement of Ecological Footprint, the carbon Footprint commercial energy) the Ecological Footprint and the Built-up . The carbon protocol measures the requirement of Footprint captures the production of CO2 biocapacity by looking only at the sink side released during the energy intensive (land required for absorbing CO2). This is collection and processing of this waste, and logically inconsistent. Moreover, the the Built-up Footprint captures the land Ecological Footprint protocol cannot indicate demand for infrastructure, which includes whether a given land use can or cannot be areas appropriated for waste disposal such as counted as contributing to sustainability. For landfills and associated infrastructure. example, the land area required for disposal of waste, such as landfills and associated infrastructures may indicate a sustainability problem, as many living close to a landfill can testify, when the landfill is unsafe and unhealthy. This is the same issue flagged in questions 6 and 7 above.

9. Can the assessments generated by Ecological Footprint Accounting methodology define: (i) whether the flows considered in the quantitative assessment are in steady-state or referring to transitional states (i.e. flows obtained by stock depletion and filling of sink); (ii) how much these flows are beneficial to the economy; and (iii) how much these flows are damaging ecological funds; why should assessments of exported (or imported) biocapacity be relevant? 18

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus Assessments of Ecological Footprint and (i) Conceptually, Ecological Footprint Biocapacity are used to calculate the surplus accounts are capital maintenance accounts in or deficit of biocapacity determined by the that they analyze flows from the perspective terms of trade. However, we should not be of whether they lead to net change in stocks surprised to find countries that externalize (depletion and/or accumulation). In other

18 Question formulated by Giampietro and Saltelli

13 their requirement of bio-capacity (using words, they calculate the flows required to someone else’s land) thanks to favorable avoid a change in stocks. terms of trade. Countries trade exactly to exchange what they have in excess with All demand and all regeneration are something they need. Sparsely populated expressed as flows – in consistent units – countries with an of natural contrary to the claims of Giampietro and resources are likely to export their bio- Saltelli (Borucke et al. 2013). These flows capacity in exchange for capital intensive or represent humanity’s demand on and information intensive goods. At the level of nature’s supply of a given set of ecological the whole planet the effect of trade is zero services. (it is a zero sum game). At the country level, the Ecological Footprint does not provide (ii) Given the biophysical limits of the planet, relevant information about local and the finite ability of the environment to environmental impacts – what types of regenerate resources, the human economy is biocapacity are required to generate the a subsystem which resides within the system traded flows. of the environment. requires that these flows (as Addressing this issue would require the use described in answer 1) meet minimum of spatial analysis and addressing explicitly material conditions of sustainability. When the issue of multi-scale analysis. these conditions are not met, the system is in ecological overshoot. Both transitional flows Since by definition the Ecological Footprint and steady-state flows play a part in the cannot say whether a country’s input in accounts and as currently measured, biocapacity is achieved at the expenses of continued overshoot leads to a depletion of another country’s irreversible depletion, the ecological assets. Such depletion, while not information of the Ecological Footprint assessed by Footprint accounts, could include cannot be used to target virtuous bilateral loss of groundwater, soil, fish stock, forest policies but only the generically single out for biomass, or carbon accumulation in the blame countries importing biocapacity. atmosphere.

(iii) Specific assessments of damage to ecological assets can give useful information about their ability to maintain current levels of production flows in the future. These lines of research are important and still contain significant knowledge gaps. As stated in question 1, Ecological Footprint accounting aims to answer a core question related to resource production and consumption. It is related to, but does not answer specific questions related to ecosystem damage.

NFAs track incoming and outgoing flows but do not inform whether specific flows of

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income can be maintained in the long-run. Comparisons of these incoming and outgoing flows indicate where unsustainable imbalances occur.

10. How is the Ecological Footprint Accounting similar or different from other international metrics/indicator systems?19

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus The Ecological Footprint is different from Ecological Footprint Accounting and the main other international metrics or indicators output, the National Footprint Accounts are because it violates simultaneously: unique in three ways (i) semantic rules – the assessment of what is  Consumption (Ecological Footprint) proposed as biocapacity. The assessment can be compared to a biophysical provided by the Ecological Footprint protocol budget limitation (biocapacity). should be called bio-contingency or  Data is aggregated to a single agricultural productivity instead, as the comparable unit of biocapacity (gha). capacity of land to produce and absorb flows  Time series of flows are provided used by humans depends mainly on the use (1961 to 2011) of human technology and the amount of fossil energy used as inputs at a given time Additionally, this is a subject with potential point and location. By measuring what is for a long discussion. To orient the happening today (bio-contingency, including discussion, it is important to make a the over-exploited cow and the stock of milk distinction between accounts and composite in the metaphor discussed in the answer 6) indices. The Ecological Footprint framework rather than what is sustainable (the healthy provides accounts. Accounts add components cow), the Ecological Footprint makes a together using a common unit of measure. disservice to the ecological community ; Other examples of accounts are GDP, (ii) common sense rules – the more greenhouse gas inventories (with CO2 ecological systems are altered the higher equivalents as unit), water accounts. becomes their biocapacity; Accounts can therefore compare, for (iii) formal rules of accounting - dimensional instance income with expenditure, as both inconsistency in the proposed equations, are also using the same measurement unit. where flows of CO2 (dimensions kg/s) are Therefore, flows of CO2 emission of an 2 offset by stocks of land (dimensions kg/m ); activity can be contrasted with flows of (iv) formal rules of sensitivity analysis – the annual CO2 sequestration of an area of land. continuous shift of quantitative assessments Both are measured in the same units across scales makes the quantitative output (kg/year). very fragile due to cumulated uncertainty in

19 Question formulated by the Footprint Network

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the conversion factors and the rounding of Composite Indices aggregate data across the values (Saltelli et al. 2008). different domains which may not have Finally, the Ecological Footprint is also equivalent units, and subjectively assign different from the other measures listed in weights to the various domains to determine the answer to question 3 by its ambition to their relative value. Such indices score a reach the bottom-line with a single number, situation according to a defined set of rules such as in its “Earth Overshoot Day” and based on expert judgment. They are campaign. In relation to this point we can therefore outside of the realm of pure only recall the quote of Einstein: “make scientific inquiry. everything as simple as possible, but not simpler”. Table 1 compares accounts with aims similar to those of Ecological Footprint accounting: quantifying human use of natural capital.

Regarding the breaking of common sense rules, readers are encouraged to review Goldfinger et al. (2014) for a description of how altering ecosystems does not necessarily determine an increase in biocapacity. 109 11. Summarizing the discussions

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus We acknowledge the good intentions behind Using the Ecological Footprint to derive the Ecological Footprint and the policies requires a proper understanding of commitment of its proponents. We advise the question that the tool addresses. against its use because the Ecological Otherwise one may not be able to draw valid Footprint metric is affected by serious conclusions from the results. methodological flaws: To increase clarity, discussions as conducted (1) The Ecological Footprint equates in this paper about the method and possible “agricultural productivity” with misunderstandings are essential. They “biocapacity”. Agricultural productivity is hopefully improve researchers’ presently boosted by reliance on non- understanding of the actual method, identify renewable fossil energy (stock depletion) research areas for improvements, and and (associated with soil highlight areas where a communication erosion, pesticides, phosphorous and deficit may have led to misinterpretations. nitrogen leaking into the water, loss). This increase in productivity carries an For this discussion, we therefore started by ecological impact, which is not captured by identifying the purpose and scope of this the Ecological Footprint accounting; accounting tool. Ecological Footprint Accounts ask, “In a given year, how much of (2) The Ecological Footprint misleads on the biosphere’s regenerative capacity did

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energy security. Several planets would be human activities demand?” Therefore, it does needed to generate agro- (Giampietro not measure, for instance, energy security, and Mayumi, 2009) matching present energy but may provide relevant insights into the consumption. The Ecological Footprint topic. ignores this because it considers only the requirement of land for absorbing CO2 and Furthermore, we emphasized the following: not for producing fuels. The Ecological Footprint is not a measure of human impact, nor is it a predictive measure (3) The Ecological Footprint ignores that a of the sustainability of specific management given forest area can absorb emissions only practices. It is an accounting system that during growth. When the forest becomes compares human demand on Earth’s mature additional forest area is needed. ecosystems to what these ecosystems are Therefore the assessment of land demand able to renew. should not be given in “number of hectares” but as “a quantity of hectares which is a Given this scope and knowledge, Ecological function of time”; Footprint accounts should be used as a necessary but not sufficient minimum (4) The Ecological Footprint neglects scales. reference framework that approximates all of At the local scale some societies can import humanity’s demands on nature that compete “ghost land” because other societies export for biologically productive area. it. At the global level this type of accounting generates a “zero sum game”. In fact, when ignoring the area required for carbon sink, between 1961 and 2001 the ecological footprint of the planet for the other inputs remained basically the same in spite of doubling , 6 times increase in economic activity and 2.5 times increase in food production (Giampietro and Saltelli, 2014). 110 111 112 CONCLUSIONS 113 114 Due to the selected form of this paper, these short conclusions for sure will not include any 115 valuation of the answers and statements. Much more, we hope that some urgent 116 challenges, limitations, and misunderstandings of the Ecological Footprint approach have 117 become clearer, as well as the potential value added from this approach. The respective 118 conclusions can be drawn by the reader. Concerning the future development of the footprint 119 approach and its applications, the critical remarks are understood as demands for clarification, 120 improvement, future development and information to critically ensure the users about the 121 potentials and limitations of the concept. 122

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123 Global Footprint Network’s researchers acknowledge that several aspects of the Footprint are 124 misunderstood and possibly based on outdated versions of the method. Therefore, establishing 125 clarity around Footprint-related definitions is paramount to guide future scientific debate and 126 provide meaningful applications. As part of this effort, the Footprint community should aim to 127 improve communication around what the Ecological Footprint can and cannot do. The authors 128 also acknowledge that methodological advances are needed in a few key areas of Footprint 129 accounting (see for instance Kitzes et al., 2009). To progress from the points of departure in this 130 paper and continue methodological advances, the authors extend a call for open collaborations 131 with academic researchers who aim to improve quantitative approaches to measure human 132 demand on nature against nature’s ability to renew for the formulation and monitoring of 133 sustainability policies. 134 135 On a more general level, the discussion held in this paper elucidates some general problems of 136 environmental indication and especially of sustainability representations. As sustainable 137 development is an extremely complex process it is not possible to represent its multiple 138 features with one indicator set alone. Thus also the footprint cannot indicate sustainability as a 139 whole, but it can look at some attributes of sustainability from a very distinct perspective. 140 Caveats as to the limited scope of any measurement can be assigned to any sustainability 141 indicator set. Hence, more indicators need to be integrated in any meaningful analysis. 142 143 Another conclusion arising from the experience of this paper is the visible demand and 144 necessity of discussions and arguments about indicator qualities, contextual limitations and 145 problems. There are several severe conceptual and methodological challenges which all actors 146 have to face in indicator development. As stated in the introduction – a basic element of 147 scientific progress is the capacity to settle disputes via scientific arguments. 148 149 As such, and given the current proliferation of indicators and the information overload policy 150 makers have to face, research is needed in exploring the synergies among sustainability 151 indicators and to evaluate how they can complement each other (and jointly reduce their own 152 limitations) in monitoring sustainability. An assessment of the linkages between Ecological 153 Footprint accounting and other measures such as ecosystem services or wealth accounting (see 154 also other measures listed in question 3 and Table 1), could be highly relevant for the 155 readership of the Ecological Indicators journal as well as for all other actors interested in both 156 indicators’ development and use. 157 158 In the end, we all, editors, critical and defending authors celebrate this attempt to bring key 159 questions to the table and to wrestle with clarifying constructively and sincerely the different 160 perspectives. We have succeeded if we provided input for the entire community to better 161 understand the potential utility and limitations of an approach like Ecological Footprint 162 accounting. While we are still far away from agreement in how to quantify or even clearly 163 define a sustainable human economy, it is worthwhile pursuing the search for solutions through 164 the use of sustainability indicators, even if potentially elusive. 165

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166 The authors on both sides do agree that exercise like this one and the format of this paper can 167 represent an effective method to enhance the quality check on the development of new 168 scientific approaches. In fact, it is important to avoid ending up in scientific disputes that can 169 be described as ‘scientists throwing numbers at each other’. The present paper will hopefully 170 contribute useful elements to help the reader form her/his own opinion on the merits of and 171 the need for an Ecological Footprint. 172 173 174 175 176 References 177 178 Blomqvist, L., Brook, B.W., Ellis, E.C., Kareiva, P.M., Nordhaus, T., Shellenberger M., 2013. Does 179 the shoe fit? Real versus imagined ecological footprints. PLoS Biol. 11 (11), e1001700, 180 http://dx.doi.org/10.1371/journal.pbio.1001700. 181 Borucke, M., Moore, D., Cranston, G., Gracey, K., Iha, K., Larson, J., Lazarus, E., Morales, J.C., 182 Wackernagel, M., Galli, A., 2013. Accounting for demand and supply of the biosphere’s 183 regenerative capacity: The National Footprint Accounts’ underlying methodology and 184 framework. Ecological Indicators 24, 518–533. 185 Brown, M.T. and S. Ulgiati. 2004. Emergy and . In C. Cleveland (ed) 186 Encyclopedia of Energy. Elsevier, New York, NY, USA. 187 Bullock, H., Mountford, J. & Stanley, R. (2001) Better Policy Making. Centre for Management 188 and Policy Studies, Cabinet Office, , UK. 189 Certain G, Skarpaas O, Bjerke J-W, Framstad E, Lindholm M, et al. (2011) The Nature Index: A 190 General Framework for Synthesizing Knowledge on the State of Biodiversity. PLoS ONE 191 6(4): e18930. doi:10.1371/journal.pone.0018930 192 Certain, G., Nybø, S., Barton, D. et. al. (2013) The SEEA Experimental Ecosystem Accounting 193 framework: Structure, Challenges, and Links with the Nature Index. Working document 194 prepared for the Expert Group Meeting: Modelling Approaches and Tools for Testing of 195 the SEEA Experimental Ecosystem Accounting, 18 - 20 November 2013, UN 196 Headquarters, New York, USA. 197 Cornell, S. (2012) "On the System Properties of the Planetary Boundaries" Ecology and Society, 198 17 (1): r2. 199 Daly, H.E., 1990. Towards some operational principles of sustainable development. Ecological 200 Economics 2, 1–6. 201 Daly, H. E. & J. Cobb (1989): For the Common Good. Beacon Press, Boston 202 Fischer-Kowalski, M., F. Krausmann, S. Giljum, S. Lutter, A. Mayer, S. Bringezu, Y. Moriguchi, H. 203 Schütz, H. Schandl and H. Weisz. 2011. Methodology and Indicators of Economy-wide 204 : State of the Art and Reliability Across Sources, Journal of 205 , Vol 15 Issue 6, pages 855–876, DOI: 10.1111/j.1530- 206 9290.2011.00366.x

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207 Galli, A., 2015. On the Rationale and Policy Usefulness of Ecological Footprint Accounting: the 208 case of Morocco. & Policy, 48, 210 – 224 209 Georgescu-Roegen, N. 1975 Energy and the Economic Myth Southern Economic Journal 210 41(3):347-381 211 Giampietro, M., Aspinall R. Ramos-Martin J. and Bukkens, S. 2014 Resource Accounting for 212 Sustainability: the nexus between Energy, Food, Water and Land use. Routledge 213 Giampietro, M., Mayumi, K. and Sorman A.H. 2012 The Metabolic Pattern of Society: Where 214 Economists Fall Short. Routledge 215 Giampietro, M. Saltelli A. (2014a): Footprint to nowhere Ecological Indicators 46: 610–621 216 217 Giampietro, M. and A. Saltelli (2014b): Footworking in circles: Reply to Goldfinger et al. (2014) 218 “Footprint Facts and Fallacies: A Response to Giampietro and Saltelli (2014) Footprints 219 to nowhere”. Ecological Indicators, Volume 46, November 2014, Pages 260-263 220 Giljum, S., Hammer, M., Stocker, A., Lackner, M., Best, A., Blobel, D., Ingwersen, W., Naumann, 221 S., Neubauer, A., Simmons, C., Lewis, K., Shmelev, S., 2007. Scientific assessment and 222 evaluation of the indicator “Ecological Footprint“. Project Z 6 – FKZ: 363 01 135, Final 223 Report. German Federal Environment Agency, Dessau. 224 Goldfinger, S. M. Wackernagel, A. Galli, E. Lazarus and D. Lin (2014): Footprint facts and 225 fallacies: A response to Giampietro and Saltelli (2014) “Footprints to Nowhere”. 226 Ecological Indicators, Volume 46, November 2014, Pages 622-632 227 Guntenspergen G.R., editor 2014 Application of Threshold Concepts in 228 Decision Making. Springer. 327 pp. 229 Hertwich, Edgar G., and Glen P. Peters, 2009. Carbon Footprint of Nations: A Global, Trade- 230 Linked Analysis. Environ. Sci. Technol., 2009, 43 (16), pp 6414–6420 231 Ioannidis, J. P. (2014). How to Make More Published Research True. PLoS medicine, 11(10), 232 e1001747. 233 Kay, J.J., T. Allen, R. Fraser, J.C. Luvall, and R.E. Ulanowicz. 2001. Can we use energy based 234 indicators to characterize and measure the status of ecosystems, human, disturbed and 235 natural? Pp. 121-133 In. S. Ulgiati, M.T. Brown, M. Giampietro, R.A. Herendeen and K. 236 Mayumi (Eds.) Advances in Energy Studies: Exploring Supplies, Constraints and Strategies 237 SG Editoriali: Padova. 238 Kitzes, Justin, and . 2009. “Answers to Common Questions in Ecological 239 Footprint Accounting.” Ecological Indicators 9 (4): 812–17. 240 Krausmann, Fridolin, Karl-Heinz Erb, Simone Gingrich, Helmut Haberl, Alberte Bondeau, 241 Veronika Gaube, Christian Lauk, Christoph Plutzar, and Timothy D. Searchinger. 2013, 242 Global human appropriation of net primary production doubled in the 20th century, 243 PNAS, vol. 110 no. 25 pp 10324–10329, doi: 10.1073/pnas.1211349110 244 Lancet, Editorial, 2015, Rewarding true inquiry and diligence in research, 385, p. 2121. 245 Lin, D., M. Wackernagel, A. Galli and R. Kelly (2015): Ecological Footprint: Informative and 246 evolving – A response to van den Bergh and Grazi (2014). Ecological Indicators, Volume 247 58, November 2015, Pages 464-468 248 Madrid C., Cabello V., Giampietro M. 2013. Water-Use Sustainability in Socio-Ecological 249 Systems: a Multi-Scale Integrated Approach. BioScience 63 (1): 14-24.

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250 Mancini, et al. 2015. Ecological Footprint: Refining the carbon Footprint Calculation. Ecological 251 Indicators. doi:10.1016/j.ecolind.2015.09.040 252 Nature, 2015, Misplaced faith, Editorial, June 2, The public trusts scientists much more than 253 scientists think. But should it? 522, 6. 254 Odum, H.T. 1996. Environmental Accounting: Emergy and environmental decision-making. John 255 Wiley & Sons. 256 Patrício, J., Ulanowicz, R., Pardal, M.A. & Marques, J.C. 2006. Ascendency as 257 for environmental quality assessment at the ecosystem level: A case study. 258 Hydrobiologia 555:19-30. 259 260 Pedersen, B., Nybø, S. and Skarpaas, O. 2013. Ecological framework for the Nature Index. A 261 more rigorous approach to the determination of reference values and selection of 262 indicators. - NINA Minireport 442. 28 pp 263 Rockström, J., W. Steffen, K. Noone, Å. Persson, F. S. Chapin, III, E. Lambin, T. M. Lenton, M. 264 Scheffer, C. Folke, H. Schellnhuber, B. Nykvist, C. A. De Wit, T. Hughes, S. van der Leeuw, 265 H. Rodhe, S. Sörlin, P. K. Snyder, R. Costanza, U. Svedin, M. Falkenmark, L. Karlberg, R. 266 W. Corell, V. J. Fabry, J. Hansen, B. Walker, D. Liverman, K. Richardson, P. Crutzen, and J. 267 Foley. 2009. Planetary boundaries:exploring the safe operating space for 268 humanity. Ecology and Society 14(2): 32. [online] URL: 269 http://www.ecologyandsociety.org/vol14/iss2/art32/ 270 Rockström, J.; Steffen, W.; Noone, K.; Persson, Å.; Chapin, F. S.; Lambin, E. F.; Lenton, T. M.; 271 Scheffer, M.; Folke, C. 2009b, "A safe operating space for humanity", Nature 461 (7263): 272 472–475. 273 Saltelli A, Ratto M, Andres T, Campolongo F, Cariboni J, Gatelli D, Salsana M, Tarantola S (2008) 274 Global sensitivity analysis - The primer. Wiley 275 SENPLADES (Secretaría Nacional de Planificación y Desarrollo), 2010. National Plan for Good 276 Living 2009-2013. English summary available at : http://www.planificacion.gob.ec/wp- 277 content/uploads/downloads/2012/08/versi%C3%B3n-resumida-en-ingl%C3%A9s.pdf 278 Simmons, C., Kevin Lewis, and John Barrett, 2000. Two feet-two approaches: a component- 279 based model of ecological footprinting. , 32(3), 375-380. 280 Steffen, Will, Katherine Richardson, Johan Rockström, Sarah E. Cornell, Ingo Fetzer, Elena M. 281 Bennett, R. Biggs, et al. 2015. “Planetary Boundaries: Guiding Human Development on a 282 Changing Planet.” Science, 1259855. 283 Ulanowicz, R.E. 1996. Trophic flow networks as indicators of ecosystem stress. pp. 358-368, In: 284 G. Polis and K. Winemiller (eds.), Food Webs: Integration of Patterns and Dynamics. 285 Chapman-Hall, New York. 286 van den Bergh,J., and Fabio Grazi, 2015, Reply to the first systematic response by the Global 287 Footprint Network to criticism: A real debate finally?, 288 http://dx.doi.org/10.1016/j.ecolind.2015.05.007 289 Wackernagel, Mathis, Gemma Cranston, Juan Carlos Morales, Alessandro Galli, 2014. “Chapter 290 24: Ecological Footprint Accounts: From Research Question to Application,” Giles

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291 Atkinson, Simon Dietz, Eric Neumayer and Matthew Agarwala (eds.), 2014, Handbook of 292 Sustainable Development: second revised edition. Edward Elgar Publishing, Cheltenham, 293 UK ISBN-13: 978-1782544692 294 Wackernagel, M, 1991. "Land Use: Measuring a Community's Appropriated Carrying Capacity as 295 an Indicator for Sustainability"; and "Using Appropriated Carrying Capacity as an 296 Indicator, Measuring the Sustainability of a Community." Report I & II to the UBC Task 297 Force on Healthy and Sustainable Communities, Vancouver. 298 Wackernagel, M., Rees, W.E., (1996). Our Ecological Footprint: Reducing Human Impact on the 299 Earth. New Society Publishers: Gabriola Island, Canada. 300 Wackernagel, M., “Ecological Footprint and Appropriated Carrying Capacity: A Tool for Planning 301 Toward Sustainability.” 1994. Ph.D. Thesis. School of Community and . 302 The University of British Columbia. 303 http://circle.ubc.ca/handle/2429/7132; http://circle.ubc.ca/bitstream/handle/2429/71 304 32/ubc_1994-954027.pdf?sequence=1 305 Wackernagel, M., Schulz, B., Deumling, D., Linares, A.C., Jenkins, M., Kapos, V., Monfreda, C., 306 Loh, J., Myers, N., Norgaard, R., Randers, J., 2002. Tracking the ecological overshoot of 307 the human economy. Proc. Natl. Acad. Sci U.S.A. 99 (14), 9266–9271. 308 Weinzettel, Jan, Kjartan Steen-Olsen, Edgar G. Hertwich, Michael Borucke, and Alessandro Galli. 309 2014. “Ecological Footprint of Nations: Comparison of Process Analysis, and Standard 310 and Hybrid Multiregional Input–output Analysis.” Ecological Economics 101 (May): 115– 311 26. doi:10.1016/j.ecolecon.2014.02.020. 312 Whitby, A., Seaford, C., Berryal, C., 2014. ‘BRAINPOoL Project Final Report: Beyond GDP – From 313 Measurement to Politics and Policy’. BRAINPOoL deliverable 5.2, A collaborative 314 programme funded by the European Union’s Seventh Programme for research, 315 technological development and demonstration under grant agreement No. 283024. 316 Available at: http://www.brainpoolproject.eu/wp- 317 content/uploads/2014/05/BRAINPOoL-Project-Final-Report.pdf 318 Wijkman, A. and Rockström, J. (2012) Bankrupting Nature: Denying Our Planetary Boundaries A 319 report to the Club of Rome, Routledge. 320 321 322 323 324 325 326 327 328 329 330 331

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Table 1 by Lin, Wackernagel, Galli, Goldfinger and Lazarus: Comparing the footprint accounts with similar approaches

Genuine Mass Flow Analysis Footprint and Carbon WAVES/Genuine Inclusive Progress Concept Planetary Boundaries (also called HANPP TEEB Biocapacity Footprint Saving Wealth Indicator (GPI ‘material footprint’) or ISEW) Herman Daly, Organizatio Global Footprint Stockholm Resilience UN John & Cliff - Wuppertal Institute IEA/IPCC World Bank UNEP ns Network Centre University Cobb, Redefining Progress, others How much of the What are planetary How much mass How much How much net wealth How much What is the net How much net What is the regenerative capacity of boundaries, and for each moves through an CO2 from does a country have? wealth is in income of a primary production economic value What the biosphere is occupied one of them, how close is economy? fossil fuel is How does it change year a country? country, is appropriated by of ecosystem research by human demand? humanity to those limits? released to year? (focus on natural How does it including non- human economies services? question is (Plus, where does within a capital) change year market benefits, from the being demand originate, and country? to year? and excluding ecosystems within answered? how is the biocapacity Also by a defensive their region? distributed on the or expenditures? planet?) activity. In the 21st century, Makes a scientific global More mass flow is a Future Is overall wealth Is overall GPI adjusts GDP How intensively How big are biocapacity is case for a number of proxy for the overall climate (measured in monetary wealth for aspects that are they using their ecological How is this increasingly a limiting dimensions. Adds amount of resource treaties could value) building up per (measured subtract from own ecosystems? benefits question factor for the human credibility to the possibility being used. put a capita? If not, this is a in monetary wellbeing, and Higher usages, in compared to relevant to economy. It is essential of global overshoot. May limitation on risk to income generation value) adds those that combination with economic understandi to know how much you not be easily applicable at this emission, in the future. building up are missing, high net imports, benefits? Are ng a have, how much you use, local scale. Not clear what through per capita? making the put countries at there hidden country's (or and what the trends are. trade-offs are among prices, or If not, this is measure a more risk. High usages costs that other boundaries. regulations. a risk to realistic could also lead to overshadow entity's) risk To set targets income assessment of degradation. benefits? Are and and monitor generation what the true there both opportunity progress, in the future. annual income of economically exposure? metrics are a nation is. and ecologically needed. better options for development? Metric global hectares kg/yr / kg/yr kg/year kg/year $ $ $ kg biomass/year $/yr www.footrpintnetwork.or www.stockholmresilience.o www.wupperinst.org www.Ipcc.ch www.wavespartnership.o inclusivewe rprogress.org/sust http://www.uni- www.teebweb.or g rg www.materialflows.n Hertwich and rg althindex.or ainability_indicat klu.ac.at/socec/inh g Wackernagel et al. 2014 Rockström et al 2009 et Peters 2009 g ors/genuine_prog alt/1.htm see website for Key websites Fischer-Kowalski see website for reports see website ress_indicator.ht Krausemann et al. reports et al. 2011 for reports m 2013

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Provides the bottom-line Each one of the planetary Kg easy to There is a Dollars speak loudly to Dollars Dollars speak Biophysical Powerful case answer to a central boundaries can easily be understand, directly scientific traditional economic speak loudly loudly to assessment. stories. question: Is there enough communicated and are links to tracked mass effort behind analysts. to traditional Applicable to biocapacity to maintain known to most publics. Can flows of categories. carbon traditional economic business and the metabolism of the build on independent robust accounting. economic analysts. GPI policy contexts. Strengths economy? Area is scientific assessments in Some statistical Public is analysts. relates clearly to relatively easy to each domain. offices now track starting to be GDP, possibly understand - it is like a mass flows. more the most farm. Has been tested by sensitive to prominent policy 12 national governments. basic climate indicator. science.

Many details could be Some boundaries are global Mass flow accounts CO2 in Dollars are unstable Dollars are Dollars are Tool cannot Not improved beyond the (CO2), others are local are at the basis of isolation is predictors of the future. unstable unstable establish clear comprehensive current accounts that use (water, nitrogen). Difficult Footprint accounts. hard to tackle Prices can fluctuate by predictors of predictors of the ecological limits to yet. Also mostly 6,000 data points per to understand trade-offs But it is less clear since self- magnitudes. They only the future. future. Prices can demand. Does not based on country and year. The among them. Difficult to what question they interest for show current human Prices can fluctuate by deal with trade. financial value accounts, however, are apply at sub-planetary answer. One kg of those preferences in the market, fluctuate by magnitudes. They assessments. constantly being refined. scale. gravel has different reducing not ecological necessities. magnitudes. only show current There is currently no demand on nature their They only human direct link to financial than one kg of wood. emission is show preferences in the figures, which makes it (Apart from weight, not obvious current market, not harder to communicate to in what way are they or may be human ecological finance oriented ecologically equal?) absent. Just preferences necessities, or Weaknesses audiences. However, How do mass flows focusing on in the resource limits. numbers can be link to supply? Which CO2 may market, not What is added or interpreted for them. mass flows are detract from ecological subtracted from included and which all other necessities. GDP to get GPI ones not, and why? environmenta Results are can be arbitrary, a While having good l pressures. counterintuit problem which material statistics is ive, and could be fundamental, result suggest that overcome with interpretation (or how natural clear and widely to use them to guide capital has accepted policy) is not as extremely accounting obvious. low value. standards for GPI calculations.

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Manuscript Click here to view linked References

1 QUESTIONING THE ECOLOGICAL FOOTPRINT 2 3 Alessandro Galli1, Mario Giampietro2, Steve Goldfinger3, Elias Lazarus4, David Lin5, Andrea 4 Saltelli6, Mathis Wackernagel7, Felix Müller#8 5 6 ABSTRACT 7 In this perspective paper a critical discussion about the concept of the Ecological Footprint is 8 documented based on 10 questions which are answered from critical and supporting points-of- 9 view. These key questions are directed towards the underlying research objectives of the 10 approach, a comparison with similar concepts, the quantification methodology and its accuracy, 11 the characteristics of the observed flows, the role of scales and resolutions, the implementation 12 of food security, the utility of the ecological footprint for society, the political relevance of the 13 concept and the differences from other international indicator systems. 14 15 KEY WORDS 16 Footprint relevance, footprint methodology, footprint applicability, footprint utility, footprint 17 critics 18 19 HIGHLIGHTS 20  10 key questions concerning the Ecological Footprint are asked 21  The questions are answered from a critical and a supporting viewpoint 22  Overall, discussion and clarity regarding indicators and their representation of 23 sustainability is needed and should be continued 24 INTRODUCTION

1 Global Footprint Network, 7-9 Chemin de Balexert, 1219 Geneva, Switzerland. Tel.+39-346-6760884, E-mail: [email protected] 2 Institució Catalana de Recerca i Estudis Avançats (ICREA), ICTA-UAB and Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona (ICTA-UAB), E-mail: [email protected] 3 Global Footprint Network, 312 Clay Street, Suite 300, Oakland, CA 94607-3510, USA, E-mail: [email protected] 4 Global Footprint Network, 312 Clay Street, Suite 300, Oakland, CA 94607-3510, USA, Tel. +1-510-839-8879, E- mail: [email protected] 5 Global Footprint Network, 312 Clay Street, Suite 300, Oakland, CA 94607-3510, USA, Tel. +1-510-839-8879, E- mail: [email protected] 6 Centre for the Study of the Sciences and the Humanities (SVT) - University of Bergen (UIB); Institut de Ciència i Tecnologia Ambientals (ICTA) -Universitat Autonoma de Barcelona (UAB),E-mail: [email protected] 7 Global Footprint Network, 312 Clay Street, Suite 300, Oakland, CA 94607-3510, USA, Tel. +1-510-839-8879, E- mail: [email protected] 8 Institute for Natural Resource Conservation, University of Kiel, Olshausenstrasse 75, D 24118 Kiel, Germany.Tel. +49431-8803251, E-mail: [email protected] # corresponding author 1

25 Scientific debates are focal elements of progress in research and development of academic 26 conceptions and methodologies. According to the strong epistemological tradition which 27 demarcates science from other endeavors, the capacity to progress by successive refutations 28 and rectifications is a focal element of scientific discussions. Although they are sometimes 29 executed in an obstinate and less tolerant atmosphere, the outcome can be a productive “cross 30 fertilization”, opening the objects of research for new aspects, setting new questions, 31 demanding for adapted concepts and targets and widening the knowledge in the respective 32 field of science. 33 Indicators provide aggregated and simplified information on phenomena which often are hardly 34 directly determinable, and as such they are suitable objects of intensive debates: Their 35 definitions, the relations to the indicandum, the elaborated methodology and its transparency, 36 the respective measurements and collections, the produced results and their interpretations 37 are often related with certain inaccuracies and uncertainties. Furthermore, the contextual 38 extents of indicators as well as their degrees of aggregation provide a wide field of problems, 39 challenges, potential ambiguities, normative loadings and, consequently severe discussions. 40 In the following, unusual article, a hopefully constructive step in the scientific debate about the 41 Ecological Footprint is made: The paper is based on the exchange of several letters, replies and 42 articles in which conceptual and methodological aspects of the Ecological Footprint have been 43 discussed in this journal (see Giampietro and Saltelli 2014 a, b, Goldfinger et al. 2014, Lin et al. 44 2015 and additionally van den Bergh and Grazi 2015). To avoid a long-term sequence of papers 45 the authors agreed to produce this joint perspective article. It aims to shed light on the roots of 46 ongoing critical discussions regarding the Ecological Footprint and its methodology. This has 47 been boiled down to ten key questions by which we identify strengths and limitations of the 48 Ecological Footprint from different perspectives. Therefore, in this article the authors do not 49 agree with the overall contents; In the opposite, the paper is documenting basic disagreements. 50 One perspective is offered by Mario Giampietro and Andrea Saltelli. The other perspective is 51 presented by researchers associated with Global Footprint Network: David Lin, Mathis 52 Wackernagel, Alessandro Galli, Elias Lazarus, and Steve Goldfinger. Both parties suggested five 53 questions each to frame the discussion about the validity and the utility of Ecological Footprint 54 accounting. Each perspective is offering their particular answers for all 10 questions. 55 This paper starts from a common point of departure. Both parties recognize that it is 56 fundamental for policy formulation and monitoring to have a quantitative approach capable of 57 measuring human demand on nature against nature’s ability to provide ecological services. The 58 position of Global Footprint Network is that Ecological Footprint Accounting adds up ecological 59 services people demand in as far as they compete for biologically productive space9. According 60 to this claim the Ecological Footprint can be compared against the available bioproductive area 61 which provides these services - biocapacity for short (Borucke et al. 2013). Giampietro and 62 Saltelli, on the contrary, argue that the claim of Global Footprint Network does not stand 63 scrutiny (Giampietro and Saltelli, 2014 a, b) and that the Ecological Footprint is not a 64 quantitative approach capable of measuring human demand on nature against nature’s ability

9 For an introduction of the footprint methodology, see e.g. Borucke et al. (2013) and Wackernagel et al. (2014) 2

65 to provide ecological services, and that the results generated by this methodology are not 66 useful. This divergence of opinions led to the present paper. 67 68 Both parties suggested five questions each to frame the discussion about the validity and the 69 utility of Ecological Footprint accounting. Both parties have answered all questions. 70

71 KEY QUESTIONS

1. What underlying research question does the footprint address?10

Giampietro and Saltelli Lin, Wackernagel, Galli Goldfinger, and Lazarus The mathematical protocol developed by the Ecological Footprint accounting addresses Global Footprint Network (GFN) aims to one key question: How much of the assess man’s impact on the planet and biosphere’s regenerative capacity do human wishes to achieve this by aggregating across activities demand? This measure can then be scales and compartments, while at the same compared to the biosphere’s available time focusing on a subset of the relevant regenerative capacity. By doing so, the dimensions of man’s impact. Thus the Ecological Footprint framework accounts for measures arrived at by the Global Footprint 1) the magnitude of humanity’s physical Network - the quantitative assessments metabolism and 2) the demand such labeled as “Ecological Footprint” and metabolism places on the Earth’s “Biocapacity” - have a purported ecosystems. Thus, it captures a necessary, resemblance with the regenerative and but not sufficient, condition for sustainability. absorptive capacity of the biosphere but no descriptive power. The Ecological Footprint framework is not a measure of total human impact but a proxy A research question on man’s impact on the for human pressure on ecosystems. planet is asked and left unanswered, while a full metaphorical apparatus is developed to In concept, the Ecological Footprint is the communicate the result of this analysis as an sum of ecosystem services used by humans, overall measure of man’s impact, such as the to the extent that these services occupy ‘Earth overshot day’. Stating that ‘August 13 mutually exclusive, biologically productive is Earth Overshoot Day 2015’ area. These services include provision of (www.overshootday.org), and that in less resources, housing, infrastructure, and than 8 months, Humanity exhausts Earth's absorption of that population’s waste, using budget for the year is a clear answer to the prevailing technology and management question of man’s overall impact on the practices (Wackernagel, 1991; Rees and planet, but this number, precise to eight Wackernagel, 1994; Wackernagel and Rees, digits, is a misleading – an in a sense 1996; Wackernagel et al., 2002). In current reassuring - non-being. Depending on what National Footprint Accounts (NFA), direct

10 Question formulated by the Footprint Network 3 dimension of possibly irreversible impact of tracking of waste flows is limited to CO2. man on the planet is looked at this number By tracking and adding up human demands could refer to a day located decades in the competing for biologically productive space, past (see answer 4). Ecological Footprint accounts incorporate both of Daly’s sustainability principles (Daly, 1990) which stipulate that within a closed system, the harvest rate should not exceed the regeneration rate and the waste production rate should not exceed the rate of assimilation.

2. How is the question relevant or irrelevant to policy concerns?11

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus When it comes to policy concern, one should If we are to live within the ecological bear in mind: (i) “make everything as simple constraints of our planet, keeping track of as possible but not simpler” (Albert Einstein); the biophysical size of an economy – and (ii) “all models are wrong, but some are particularly compared to the size of useful” (George E.P. Box). Our criticism of supporting ecosystems – enhances effective the EF protocol moves from a critique of its policy development (Bullock, Mountford, and implausible simplifications (e.g., for energy Stanley 2001). security the only biocapacity taken into account is land absorbing CO2) to address the Assuming that human society cannot take inadequacy of the construct to deal with the more than the biosphere can renew without relevant subject matter. The questions endangering its stability, any policy we addressed by EF are relevant but the implement should consider whether it answers misleading (e.g., increasing deepens or alleviates society’s resource ecosystem alteration is deemed positive for dependence. Also, it may make sense for biocapacity). When dealing with policy each society to set explicit goals about how concern, the combination of being relevant much its economy should use compared to and scientifically wrong is unfortunate. what ecosystems can renew.

The extraordinary success of the Ecological While most governments have not yet Footprint, its take up by a myriad of committed to meaningful and effective countries and well-intended organizations, policies on consumption and resource and its frantic consumption by the media, efficiency, Ecological Footprint accounting raise deep concerns on the internal system has been incorporated into official initiatives

11 Question formulated by the Footprint Network

4 of quality control of science – which is today of at least 12 national governments or in a status of deep crisis (Lancet 2015, intergovernmental agencies (e.g., Giljum et Nature 2015, Ioannidis 2014). As of today al. 2007, SENPLADES 2010). It has been used only a handful of practitioners have moved to set targets and to guide major shifts in to context the veracity of the Ecological budgeting, sustainable investments, and Footprint (see recent reviews in Blomqvist et policy (Whitby et al. 2014). Businesses and al. 2013 and van den Bergh and Grazi 2015), financial institutions have applied it, such as and these critics have never reached neither in the World Business Council for Sustainable the top mainstream scientific journals nor Development’s Vision 2050 Project. the media. Additionally, civil organizations, such as the World Wide Fund for Nature International (WWF), use the Ecological Footprint accounts to represent human demand on natural systems.

3. If the question has some relevance, are there more accurate methods available elsewhere for answering this particular question?12

Giampietro andSaltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus Yes: Given the acknowledged lack of other *Planetary Boundaries (Rockström et al. comprehensive metrics in this domain, and 2009a; 2009b; Cornell 2012; Wijkman and the fact that Ecological Footprint accounts Rockström, 2012; have been reviewed and validated by nearly http://www.stockholmresilience.org/21/rese a dozen government studies, these accounts arch/research-programmes/planetary- represent, in our view, the best available boundaries.html) systemic approximation of a human *Nature Index (Pedersen et al. 2013; Certain population’s demand on nature. et al. 2011 ; 2013), that can be integrated into the UN System of Environmental- A unique feature of Ecological Footprint Economic Accounting; accounting is its ability to assess the size of http://unstats.un.org/unsd/envaccounting/s the human enterprise against earth’s eea.asp biological capacity, even over time. *Ecological indicators from theoretical ecology, such as EMergy analysis (Odum, Complementary approaches exist, which 1996; Brown and Ulgiati, 2004), Ascendency confirm the risks of overconsumption (see for aquatic ecosystems (Ulanowicz, 1996; also question 9). Planetary Boundaries Patricio et al. 2006), Ecosystem Integrity (Rockström et al. 2009, Steffen et al. 2015), (Guntenspergen 2014, Kay et al. 2001); for example, identify overuse in specific *MuSIASEM to study the nexus between domains. However they do not provide an

12 Question formulated by the Footprint Network

5 energy, food, water and land uses in socio- overall assessment of the ratio between ecological systems and its relation to human demand and earth’s regenerative environmental impact (Giampietro et al. ability, nor show how this relationship 2012; 2014; Madrid et al. 2013). changes over time, or show the regional distribution of overuse. The fact that none of the above methods offer the perfect tool to measure human Other approaches measure demand but are demand on nature against nature’s not able to identify limits. For example, the regenerative ability does not imply that the World Bank’s monetary natural capital Ecological Footprint has comparable assessment provides a relative value of legitimacy and quality. In its insistence to natural capital compared to other capital, but capture the big picture with just one number does not indicate whether the amount of the Ecological Footprint puts itself at odds natural capital is sufficient. Similarly, Material with the community of scientists concerned Flow Assessments track the weight of with a responsible use of quantitative material flows, but this is not compared information in sustainability science. against any regeneration rate.

4. Given the quality and accuracy limitations of current Footprint results, is society better off without these results?13

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus The results provided by the ecological The National Footprint Accounts, the main footprint are misleading and may result in application of Ecological Footprint harmful policies. According to the EF accounting, uses the standard international protocol replacing natural ecosystems with datasets and operates under the assumption more productive human-managed that people would be better off with vegetation would increase the biocapacity of decisions fully informed by available our planet. The EF protocol suggests we are empirical evidence of the biocapacity overshooting the carrying capacity of the situation. Despite representing a planet by a mere 50%, but the quantity of conservative estimate of human demand on nitrogen used in agriculture alone would nature, current global and national accounts already require 2.5 planets to be fixed by document significant biocapacity deficits (see natural processes (let alone the generation Galli et al., 2014). If the Ecological Footprint of other valuable flows or the absorption of truly is an underestimate, the implications harmful pollutants.) suggest that contracting the human metabolism is necessary, and economic The EF does not address the requirement of development strategies consistent with this sink capacity for pollutants nor the supply material need should be adopted. Rejecting these results and continuing on current

13 Question formulated by the Footprint Network

6 capacity for liquid fuels. working assumptions, which largely ignore physical constraints, would make humanity Other serious flaws have been pointed out in worse off. the journal PLoS Biology by Blomqvist et al., 2013 and by many others (for an overview Given that conservative results from the see van den Bergh, and Grazi, 2015). National Footprint Accounts (NFA) represent a minimum necessary condition, one could argue that sustainability policies based on current Ecological Footprint numbers may not be aggressive enough. However, current sustainability policies remain insufficient to address resource limitations and trends highlighted by Ecological Footprint accounts.

For a detailed explanation on specific examples such as replacement of natural ecosystems with human managed systems such as cropland, and why this does not necessarily increase biocapacity, see Goldfinger et al. (2014).

5. What are the external referents used for quantitative assessments in Ecological Footprint Accounting and what is the accuracy of the measurement schemes used to quantify their relevant characteristics?14

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus This question is not a philosophical but The majority of data used in the Footprint technical one. Before undertaking any accounts refers to annual produced measurement, two pieces of information are quantities (tonnes per year), annual needed: (i) expected characteristics of what productivity (tonnes per hectare per year) has to be measured; and (ii) the accuracy of and areas harvested/used for production of a the measurement scheme. If we want to given year (hectares) as reported by the UN. measure the height of a human being, we Currently, we cannot comprehensively assess must be able to (i) recognize an instance of the precision and accuracy of data compiled human being, i.e. what we want to measure; by UN statistics. Therefore, current National something with a height of 30 m (e.g., a Footprint Accounts calculate results under statue) is not a human being even if it looks the assumption that these data sources are like one; and (ii) use a meter with an reliable. However, discrepancies in trade admissible accuracy. An accuracy of ± 3 m is statistics allow us to compare the degree to

14 Question formulated by Giampietro and Saltelli

7 good for measuring the length of highways which a country’s trade reporting matches its but not for measuring the height of human partners reporting for what should be beings. What are the “expected identical transactions. These discrepancies characteristics” of the specific processes give insight into potential noise in the data generating biocapacity that are measured by set. EF? What is the error bar on the measurement of biocapacity expressed in Significant difficulty remains in assessing the global hectare equivalent? quality of input data; however verification reports have been performed by the national Is the accuracy of the assessment the same agencies (e.g., statistical bureaus) of several at the local, national and global level? countries (e.g., France, Switzerland, Japan, and Luxembourg). In France, for example, the The implications of these questions become independent re-running of the national clear in the answer to the next question 6. Footprint calculation with locally-sourced data has yielded results consistent with those generated by Global Footprint Network (1-4% difference). Additional assessments of NFA results continue to generate insights into potential improvement of the accounts. This includes moving towards reconciling balance-based NFAs with Multi-Regional Input-Output (MRIO), possibly leading to hybrid-MRIO based Footprint calculations (Weinzettel et al. 2014). Researchers are also refining the carbon Footprint calculation (Mancini et al., 2015).

6. When calculating Ecological Footprint and Biocapacity, is the measurement referring to the characteristics of a typology (which typology?) or to the characteristics of an instance? (An instance of what?)15

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus We answer this with a metaphor about how Ecological Footprint and biocapacity accounts to account the biocapacity of a flow. Let’s measure bioproductivity expressed as the imagine one wants to calculate the “bio- amount of global bioproductive area needed capacity” required to obtain 1,000 liters of to supply a basket of services. The National milk measured not in hectares but in number Footprint Accounts use input data of cow-day equivalents. Let’s assume that at aggregated by year, and therefore are a time

15 Question formulated by Giampietro and Saltelli

8 world level there are three ways to supply series record (1961-2011) of annual flows milk: (A) producing 6-15 liters/day per cow in (Ecological Footprint and biocapacity). production (to be reduced because of cow- Biocapacity can change with environmental days not in production); (B) producing 20-40 and managerial conditions and reflects liters/day per cow in production (ditto); (C) current conditions as opposed to a stock depletion (using stocks of long- theoretical productivity in the absence of conservation milk). Imagine to measure in a human influence. given year (2014) (i) the liters of milk supply in the world (590 billion = total liters); and (ii) Biocapacity accounts start with actual land the number of cow-days producing milk in areas (ha), which are then weighted by their the world (95 billion = total cow-days). The relative global bioproductivity (global resulting ratio, 6 liters/cow-day, reflects the hectares). Footprint accounts start with particular situation in 2014 given by the material flows such as cereals, vegetables, relative importance of the three typologies milk, wood, CO2 emissions, etc. Then the A, B and C in providing the total supply, but amount of actual land area needed to does not provide an assessment of the generate these flows is calculated. Just as “biocapacity” (expected characteristics of with biocapacity, these areas are expressed physical processes) required to produce in a common measurement unit, global 1,000 liters of milk. An assessment of 166.7 hectares. This is done by calculating the area, cow-days required for producing 1,000 liters at world average productivity, needed to of milk does reflect what happened in the generate these flows. Stocks are not tracked year 2014 (an instance) but will not provide by Footprint accounts. any information about the required “biocapacity” for producing 1,000 liters of For example, the calculation of the Ecological milk on our planet in a sustainable way. An Footprint (or biocapacity requirement) of assessment of “biocapacity” would require a milk in 2014 starts with milk produced in prior definition of the characteristics of the 2014 (not stocks). Using the production flow, elements producing the flow. These we then calculate the total amount of characteristics determine their capacity to equivalent bioproductive land required for produce the flow in a sustainable way. This the production of this milk. The Footprint of point is discussed in the next answer. milk is spread across grazing land (to provide food for milk-animals), cropland (again to provide food for milk-animals), built-up land (to provide supporting infrastructure), and forest land (to sequester CO2 emitted through electricity and fossil fuel use during the production process). For the consumption Footprint, we add to this production number the import and subtract the exports.

7. Ecological Footprint Accounting methodology generates a unique set of

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quantitative assessments obtained combining together measurements referring to processes taking place at different scales. This unique set of quantitative assessments is supposed to be equally useful for agents operating at different scales – e.g. farms, cities, provinces, nations, macro-regions, and the planet. What are the main benefits and the main limitations of this approach?16

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus The EF protocol is measuring flows without Ecological Footprint accounting provides a making a distinction among different framework for organizing information. At typologies of elements producing the flows. each spatial scale, whether global, national, Using the metaphor of milk production individual, or a single activity, appropriate described in the previous question 6 we data for these accounts is required. Simmons distinguish: et al. (2000) describe two methods to derive NFAs. The first approach follows a bottom-up Type A: flow in steady-state based on natural approach and attempts to account a processes. Cows producing milk without complete set of consumed items, and drugs with a life expectancy of over 15 years determines the Ecological Footprint of each are the external referents to be used to to of these using Life Cycle Assessment (LCA). measure natural biocapacity; Accuracy here depends on the completeness of the set, and the accuracy of the individual Type B: flow determined by human LCAs. Given a robust set of input data, this technology powered by non-renewable method can be reasonably accurate and is resources. Cows forced to produce more generally better suited for high-resolution milk with hormones and fossil-energy based specific accounts, such as those at the unhealthy diets should not be included in individual or activity level, but suffers from measurements of natural biocapacity; data availability at larger scales.

Type C : non-renewable flow. Depleting Global Footprint Network uses a second stocks of long-conservation milk has nothing method to produce the NFAs. This method is to do with biocapacity. a top-down approach which uses national aggregate input data on production, trade Summing indiscriminately the different flows, and consumption. (For a full listing of sources of milk and cows-days in 2014 inputs, see Kitzes et al. 2009). For practical generates a number that is completely implementation, regional or world average useless for policy. The resulting value of 6 data is substituted when country specific liters per cow-day does not provide any data is not available. The accuracy and relevant information for individual dairy reliability of accounts following this method farmers (when deciding how to produce are highest at global level and in countries milk: type A or B?), regional governments with robust national statistics. For finer scale regulating milk production, or national accounts such as those of a province, either governments making scenarios of the

16 Question formulated by Giampietro and Saltelli

10 environmental impact of milk production. appropriate province level data is required or lower resolution national data must be scaled Moving out of the metaphor of milk down. The latter would result in decreased production, an increase in land productivity accuracy. in agriculture based on the massive depletion of “long conservation stocks of For end users, it can be useful to track fossil energy” should not be interpreted as Footprint accounts through time and in an increase in ecological biocapacity. different spatial contexts, from household to global. Following the principles listed in All sums elaborated by the Ecological answer 1, heads of a household may make Footprint system of accounting are obtained decisions based on a particular biocapacity by mixing together characteristics of budget, just as a city or a nation could. instances belonging to different typologies (liters of milk from cows of Type A, Type B and from stocks), without even specifying the relative size of these instances in the mix.

8. Ecological Footprint Accounting measures the biocapacity required for energy security as the land requirement required to absorb the CO2 emissions. But then why does it not adopt the same logic for calculating the biocapacity required for food security – e.g. measuring the land required to absorb human dejections and food waste – rather than the land required to produce food?17

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus As explained by Georgescu-Roegen (1975) Ecological Footprint accounts do not, nor are (building on the work of Lotka and Odum) a they intended to measure energy security. society metabolizes matter and energy in Neither do they track stocks (such as the two different forms: (i) endosomatic flows – availability of fossil fuels). They only look at nutrients contained in food metabolized the demand for the annual capacity to inside the human body; (ii) exosomatic flows produce renewable resources and assimilate – energy carriers and minerals metabolized waste. This logic is followed consistently for and transformed under human control but CO2, food waste, or human dejections. outside the human body. This second metabolism requires the use of technology In the case of CO2, this service is waste (exosomatic devices). Both types of assimilation. It is a competing demand on metabolism require biocapacity for the biocapacity and therefore can be added up to supply of the input flows (to produce foods other demands. Also, to meet the minimum eaten by the population and to produce condition for sustainability in a closed energy carriers and materials used by system, in any given year waste should not

17 Question formulated by Giampietro and Saltelli

11 society) and for the sink-capacity of waste be produced faster than it is assimilated. flows (to absorb dejections and emissions). Ecological Footprint accounting therefore considers fossil fuel only from the However, when dealing with the stability of perspective of its demand on waste endosomatic metabolism (the requirement assimilation capacity (one aspect of the of food) the EF protocol measures the overall biocapacity). requirement of biocapacity by looking only at the supply side (land required for agricultural The demand on nature imposed by waste production). On the contrary when dealing food and human dejections is not discretely with the stability of the exosomatic tracked by the Ecological Footprint, but is metabolism (the requirement of commercial captured within two components of the energy) the EF protocol measures the Ecological Footprint, the carbon Footprint requirement of biocapacity by looking only at and the Built-up land Footprint. The carbon the sink side (land required for absorbing Footprint captures the production of CO2 CO2). This is logically inconsistent. released during the energy intensive Moreover, the EF protocol cannot indicate collection and processing of this waste, and whether a given land use can or cannot be the Built-up Footprint captures the land counted as contributing to sustainability. For demand for infrastructure, which includes example, the land area required for disposal areas appropriated for waste disposal such as of waste, such as landfills and associated landfills and associated infrastructure. infrastructures may indicate a sustainability problem, as many populations living close to a landfill can testify, when the landfill is unsafe and unhealthy. This is the same issue flagged in questions 6 and 7 above.

9. Can the assessments generated by Ecological Footprint Accounting methodology define: (i) whether the flows considered in the quantitative assessment are in steady-state or referring to transitional states (i.e. flows obtained by stock depletion and filling of sink); (ii) how much these flows are beneficial to the economy; and (iii) how much these flows are damaging ecological funds; why should assessments of exported (or imported) biocapacity be relevant? 18

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus Assessments of EF and Biocapacity are used (i) Conceptually, Ecological Footprint to calculate the surplus or deficit of accounts are capital maintenance accounts in biocapacity determined by the terms of that they analyze flows from the perspective trade. However, we should not be surprised of whether they lead to net change in stocks to find countries that externalize their (depletion and/or accumulation). In other

18 Question formulated by Giampietro and Saltelli

12 requirement of bio-capacity (using someone words, they calculate the flows required to else’s land) thanks to favorable terms of avoid a change in stocks. trade. Countries trade exactly to exchange what they have in excess with something All demand and all regeneration are they need. Sparsely populated countries expressed as flows – in consistent units – with an abundance of natural resources are contrary to the claims of Giampietro and likely to export their bio-capacity in Saltelli (Borucke et al. 2013). These flows exchange for capital intensive or information represent humanity’s demand on and intensive goods. At the level of the whole nature’s supply of a given set of ecological planet the effect of trade is zero (it is a zero services. sum game). At the country level, EF does not provide relevant information about local (ii) Given the biophysical limits of the planet, environmental impacts – what types of and the finite ability of the environment to biocapacity are required to generate the regenerate resources, the human economy is traded flows. a subsystem which resides within the system of the environment. Sustainable Addressing this issue would require the use development requires that these flows (as of spatial analysis and addressing explicitly described in answer 1) meet minimum the issue of multi-scale analysis. material conditions of sustainability. When these conditions are not met, the system is in Since by definition the Ecological Footprint ecological overshoot. Both transitional flows cannot say whether a country’s input in and steady-state flows play a part in the biocapacity is achieved at the expenses of accounts and as currently measured, another country’s irreversible depletion, the continued overshoot leads to a depletion of information of the EF cannot be used to ecological assets. Such depletion, while not target virtuous bilateral policies but only the assessed by Footprint accounts, could include generically single out for blame countries loss of groundwater, soil, fish stock, forest importing biocapacity. biomass, or carbon accumulation in the atmosphere.

(iii) Specific assessments of damage to ecological assets can give useful information about their ability to maintain current levels of production flows in the future. These lines of research are important and still contain significant knowledge gaps. As stated in question 1, Ecological Footprint accounting aims to answer a core question related to resource production and consumption. It is related to, but does not answer specific questions related to ecosystem damage.

NFAs track incoming and outgoing flows but do not inform whether specific flows of

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income can be maintained in the long-run. Comparisons of these incoming and outgoing flows indicate where unsustainable imbalances occur.

10. How is the Ecological Footprint Accounting similar or different from other international metrics/indicator systems?19

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus The Ecological Footprint is different from Ecological Footprint Accounting and the main other international metrics or indicators output, the National Footprint Accounts are because it violates simultaneously: unique in three ways (i) semantic rules – the assessment of what is  Consumption (Ecological Footprint) proposed as biocapacity. The assessment can be compared to a biophysical provided by the EF protocol should be called budget limitation (biocapacity). bio-contingency or agricultural productivity  Data is aggregated to a single instead, as the capacity of land to produce comparable unit of biocapacity (gha). and absorb flows used by humans depends  Time series of flows are provided mainly on the use of human technology and (1961 to 2011) the amount of fossil energy used as inputs at a given time point and location. By Additionally, this is a subject with potential measuring what is happening today (bio- for a long discussion. To orient the contingency, including the over-exploited discussion, it is important to make a cow and the stock of milk in the metaphor distinction between accounts and composite discussed in the answer 6) rather than what indices. The Ecological Footprint framework is sustainable (the healthy cow), the EF provides accounts. Accounts add components makes a disservice to the ecological together using a common unit of measure. community ; Other examples of accounts are GDP, (ii) common sense rules – the more greenhouse gas inventories (with CO2 ecological systems are altered the higher equivalents as unit), water accounts. becomes their biocapacity; Accounts can therefore compare, for (iii) formal rules of accounting - dimensional instance income with expenditure, as both inconsistency in the proposed equations, are also using the same measurement unit. where flows of CO2 (dimensions kg/s) are Therefore, flows of CO2 emission of an 2 offset by stocks of land (dimensions kg/m ); activity can be contrasted with flows of (iv) formal rules of sensitivity analysis – the annual CO2 sequestration of an area of land. continuous shift of quantitative assessments Both are measured in the same units across scales makes the quantitative output (kg/year). very fragile due to cumulated uncertainty in

19 Question formulated by the Footprint Network

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the conversion factors and the rounding of Composite Indices aggregate data across the values (Saltelli et al. 2008). different domains which may not have Finally, the EF is also different from the other equivalent units, and subjectively assign measures listed in the answer to question 3 weights to the various domains to determine by its ambition to reach the bottom-line with their relative value. Such indices score a a single number, such as in its “Earth situation according to a defined set of rules Overshoot Day” campaign. In relation to this and based on expert judgment. They are point we can only recall the quote of therefore outside of the realm of pure Einstein: “make everything as simple as scientific inquiry. possible, but not simpler”. Table 1 compares accounts with aims similar to those of Ecological Footprint accounting: quantifying human use of natural capital.

Regarding the breaking of common sense rules, readers are encouraged to review Goldfinger et al. (2014) for a description of how altering ecosystems does not necessarily determine an increase in biocapacity. 72 11. Summarizing the discussions

Giampietro and Saltelli Lin, Wackernagel, Galli, Goldfinger and Lazarus We acknowledge the good intentions behind Using the Ecological Footprint to derive the Ecological Footprint and the policies requires a proper understanding of commitment of its proponents. We advise the question that the tool addresses. against its use because the EF metric is Otherwise one may not be able to draw valid affected by serious methodological flaws: conclusions from the results.

(1) EF equates “agricultural productivity” To increase clarity, discussions as conducted with “biocapacity”. Agricultural productivity in this paper about the method and possible is presently boosted by reliance on non- misunderstandings are essential. They renewable fossil energy (stock depletion) hopefully improve researchers’ and monocultures (associated with soil understanding of the actual method, identify erosion, pesticides, phosphorous and research areas for improvements, and nitrogen leaking into the water, biodiversity highlight areas where a communication loss). This increase in productivity carries an deficit may have led to misinterpretations. ecological impact, which is not captured by the EF accounting; For this discussion, we therefore started by identifying the purpose and scope of this (2) EF misleads on energy security. Several accounting tool. Ecological Footprint planets would be needed to generate agro- Accounts ask, “In a given year, how much of biofuel (Giampietro and Mayumi, 2009) the biosphere’s regenerative capacity did

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matching present energy consumption. The human activities demand?” Therefore, it does EF ignores this because it considers only the not measure, for instance, energy security, requirement of land for absorbing CO2 and but may provide relevant insights into the not for producing fuels. topic.

(3) EF ignores that a given forest area can Furthermore, we emphasized the following: absorb emissions only during growth. When The Ecological Footprint is not a measure of the forest becomes mature additional forest human impact, nor is it a predictive measure area is needed. Therefore the assessment of of the sustainability of specific management land demand should not be given in “number practices. It is an accounting system that of hectares” but as “a quantity of hectares compares human demand on Earth’s which is a function of time”; ecosystems to what these ecosystems are able to renew. (4) EF neglects scales. At the local scale some societies can import “ghost land” Given this scope and knowledge, Ecological because other societies export it. At the Footprint accounts should be used as a global level this type of accounting generates necessary but not sufficient minimum a “zero sum game”. In fact, when ignoring reference framework that approximates all of the area required for carbon sink, between humanity’s demands on nature that compete 1961 and 2001 the ecological footprint of the for biologically productive area. planet for the other inputs remained basically the same in spite of doubling world population, 6 times increase in economic activity and 2.5 times increase in food production (Giampietro and Saltelli, 2014). 73 74 75 CONCLUSIONS 76 77 Due to the selected form of this paper, these short conclusions for sure will not include any 78 valuation of the answers and statements. Much more, we hope that some urgent 79 challenges, limitations, and misunderstandings of the Ecological Footprint approach have 80 become clearer, as well as the potential value added from this approach. The respective 81 conclusions can be drawn by the reader. Concerning the future development of the footprint 82 approach and its applications, the critical remarks are understood as demands for clarification, 83 improvement, future development and information to critically ensure the users about the 84 potentials and limitations of the concept. 85 86 Global Footprint Network’s researchers acknowledge that several aspects of the Footprint are 87 misunderstood and possibly based on outdated versions of the method. Therefore, establishing 88 clarity around Footprint-related definitions is paramount to guide future scientific debate and 89 provide meaningful applications. As part of this effort, the Footprint community should aim to 90 improve communication around what the Ecological Footprint can and cannot do. The authors 91 also acknowledge that methodological advances are needed in a few key areas of Footprint

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92 accounting (see for instance Kitzes et al., 2009). To progress from the points of departure in this 93 paper and continue methodological advances, the authors extend a call for open collaborations 94 with academic researchers who aim to improve quantitative approaches to measure human 95 demand on nature against nature’s ability to renew for the formulation and monitoring of 96 sustainability policies. 97 98 On a more general level, the discussion held in this paper elucidates some general problems of 99 environmental indication and especially of sustainability representations. As sustainable 100 development is an extremely complex process it is not possible to represent its multiple 101 features with one indicator set alone. Thus also the footprint cannot indicate sustainability as a 102 whole, but it can look at some attributes of sustainability from a very distinct perspective. 103 Caveats as to the limited scope of any measurement can be assigned to any sustainability 104 indicator set. Hence, more indicators need to be integrated in any meaningful analysis. 105 106 Another conclusion arising from the experience of this paper is the visible demand and 107 necessity of discussions and arguments about indicator qualities, contextual limitations and 108 problems. There are several severe conceptual and methodological challenges which all actors 109 have to face in indicator development. As stated in the introduction – a basic element of 110 scientific progress is the capacity to settle disputes via scientific arguments. 111 112 As such, and given the current proliferation of indicators and the information overload policy 113 makers have to face, research is needed in exploring the synergies among sustainability 114 indicators and to evaluate how they can complement each other (and jointly reduce their own 115 limitations) in monitoring sustainability. An assessment of the linkages between Ecological 116 Footprint accounting and other measures such as ecosystem services or wealth accounting (see 117 also other measures listed in question 3 and Table 1), could be highly relevant for the 118 readership of the Ecological Indicators journal as well as for all other actors interested in both 119 indicators’ development and use. 120 121 In the end, we all, editors, critical and defending authors celebrate this attempt to bring key 122 questions to the table and to wrestle with clarifying constructively and sincerely the different 123 perspectives. We have succeeded if we provided input for the entire community to better 124 understand the potential utility and limitations of an approach like Ecological Footprint 125 accounting. While we are still far away from agreement in how to quantify or even clearly 126 define a sustainable human economy, it is worthwhile pursuing the search for solutions through 127 the use of sustainability indicators, even if potentially elusive. 128 129 The authors on both sides do agree that exercise like this one and the format of this paper can 130 represent an effective method to enhance the quality check on the development of new 131 scientific approaches. In fact, it is important to avoid to end-up into scientific disputes can be 132 described as ‘scientists throwing numbers at each other’. The present paper will hopefully 133 contribute useful elements to help the reader form her/his own opinion on the merits of and 134 the need for an Ecological Footprint. 135

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136 137 138 139 References 140 141 Blomqvist, L., Brook, B.W., Ellis, E.C., Kareiva, P.M., Nordhaus, T., Shellenberger M., 2013. Does 142 the shoe fit? Real versus imagined ecological footprints. PLoS Biol. 11 (11), e1001700, 143 http://dx.doi.org/10.1371/journal.pbio.1001700. 144 Borucke, M., Moore, D., Cranston, G., Gracey, K., Iha, K., Larson, J., Lazarus, E., Morales, J.C., 145 Wackernagel, M., Galli, A., 2013. Accounting for demand and supply of the biosphere’s 146 regenerative capacity: The National Footprint Accounts’ underlying methodology and 147 framework. Ecological Indicators 24, 518–533. 148 Brown, M.T. and S. Ulgiati. 2004. Emergy and Environmental Accounting. In C. Cleveland (ed) 149 Encyclopedia of Energy. Elsevier, New York, NY, USA. 150 Bullock, H., Mountford, J. & Stanley, R. (2001) Better Policy Making. Centre for Management 151 and Policy Studies, Cabinet Office, London, UK. 152 Certain G, Skarpaas O, Bjerke J-W, Framstad E, Lindholm M, et al. (2011) The Nature Index: A 153 General Framework for Synthesizing Knowledge on the State of Biodiversity. PLoS ONE 154 6(4): e18930. doi:10.1371/journal.pone.0018930 155 Certain, G., Nybø, S., Barton, D. et. al. (2013) The SEEA Experimental Ecosystem Accounting 156 framework: Structure, Challenges, and Links with the Nature Index. Working document 157 prepared for the Expert Group Meeting: Modelling Approaches and Tools for Testing of 158 the SEEA Experimental Ecosystem Accounting, 18 - 20 November 2013, UN 159 Headquarters, New York, USA. 160 Cornell, S. (2012) "On the System Properties of the Planetary Boundaries" Ecology and Society, 161 17 (1): r2. 162 Daly, H.E., 1990. Towards some operational principles of sustainable development. Ecological 163 Economics 2, 1–6. 164 Fischer-Kowalski, M., F. Krausmann, S. Giljum, S. Lutter, A. Mayer, S. Bringezu, Y. Moriguchi, H. 165 Schütz, H. Schandl and H. Weisz. 2011. Methodology and Indicators of Economy-wide 166 Material Flow Accounting: State of the Art and Reliability Across Sources, Journal of 167 Industrial Ecology, Vol 15 Issue 6, pages 855–876, DOI: 10.1111/j.1530- 168 9290.2011.00366.x 169 Galli, A., 2015. On the Rationale and Policy Usefulness of Ecological Footprint Accounting: the 170 case of Morocco. Environmental Science & Policy, 48, 210 – 224 171 Georgescu-Roegen, N. 1975 Energy and the Economic Myth Southern Economic Journal 172 41(3):347-381 173 Giampietro, M., Aspinall R. Ramos-Martin J. and Bukkens, S. 2014 Resource Accounting for 174 Sustainability: the nexus between Energy, Food, Water and Land use. Routledge 175 Giampietro, M., Mayumi, K. and Sorman A.H. 2012 The Metabolic Pattern of Society: Where 176 Economists Fall Short. Routledge 177 Giampietro, M. Saltelli A. (2014a): Footprint to nowhere Ecological Indicators 46: 610–621

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178 179 Giampietro, M. and A. Saltelli (2014b): Footworking in circles: Reply to Goldfinger et al. (2014) 180 “Footprint Facts and Fallacies: A Response to Giampietro and Saltelli (2014) Footprints 181 to nowhere”. Ecological Indicators, Volume 46, November 2014, Pages 260-263 182 Giljum, S., Hammer, M., Stocker, A., Lackner, M., Best, A., Blobel, D., Ingwersen, W., Naumann, 183 S., Neubauer, A., Simmons, C., Lewis, K., Shmelev, S., 2007. Scientific assessment and 184 evaluation of the indicator “Ecological Footprint“. Project Z 6 – FKZ: 363 01 135, Final 185 Report. German Federal Environment Agency, Dessau. 186 Goldfinger, S. M. Wackernagel, A. Galli, E. Lazarus and D. Lin (2014): Footprint facts and 187 fallacies: A response to Giampietro and Saltelli (2014) “Footprints to Nowhere”. 188 Ecological Indicators, Volume 46, November 2014, Pages 622-632 189 Guntenspergen G.R., editor 2014 Application of Threshold Concepts in Natural Resource 190 Decision Making. Springer. 327 pp. 191 Hertwich, Edgar G., and Glen P. Peters, 2009. Carbon Footprint of Nations: A Global, Trade- 192 Linked Analysis. Environ. Sci. Technol., 2009, 43 (16), pp 6414–6420 193 Ioannidis, J. P. (2014). How to Make More Published Research True. PLoS medicine, 11(10), 194 e1001747. 195 Kay, J.J., T. Allen, R. Fraser, J.C. Luvall, and R.E. Ulanowicz. 2001. Can we use energy based 196 indicators to characterize and measure the status of ecosystems, human, disturbed and 197 natural? Pp. 121-133 In. S. Ulgiati, M.T. Brown, M. Giampietro, R.A. Herendeen and K. 198 Mayumi (Eds.) Advances in Energy Studies: Exploring Supplies, Constraints and Strategies 199 SG Editoriali: Padova. 200 Kitzes, Justin, and Mathis Wackernagel. 2009. “Answers to Common Questions in Ecological 201 Footprint Accounting.” Ecological Indicators 9 (4): 812–17. 202 Krausmann, Fridolin, Karl-Heinz Erb, Simone Gingrich, Helmut Haberl, Alberte Bondeau, 203 Veronika Gaube, Christian Lauk, Christoph Plutzar, and Timothy D. Searchinger. 2013, 204 Global human appropriation of net primary production doubled in the 20th century, 205 PNAS, vol. 110 no. 25 pp 10324–10329, doi: 10.1073/pnas.1211349110 206 Lancet, Editorial, 2015, Rewarding true inquiry and diligence in research, 385, p. 2121. 207 Lin, D., M. Wackernagel, A. Galli and R. Kelly (2015): Ecological Footprint: Informative and 208 evolving – A response to van den Bergh and Grazi (2014). Ecological Indicators, Volume 209 58, November 2015, Pages 464-468 210 Madrid C., Cabello V., Giampietro M. 2013. Water-Use Sustainability in Socio-Ecological 211 Systems: a Multi-Scale Integrated Approach. BioScience 63 (1): 14-24. 212 Mancini, et al. 2015. Ecological Footprint: Refining the carbon Footprint Calculation. Ecological 213 Indicators. doi:10.1016/j.ecolind.2015.09.040 214 Nature, 2015, Misplaced faith, Editorial, June 2, The public trusts scientists much more than 215 scientists think. But should it? 522, 6. 216 Odum, H.T. 1996. Environmental Accounting: Emergy and environmental decision-making. John 217 Wiley & Sons. 218 Patrício, J., Ulanowicz, R., Pardal, M.A. & Marques, J.C. 2006. Ascendency as ecological indicator 219 for environmental quality assessment at the ecosystem level: A case study. 220 Hydrobiologia 555:19-30.

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221 222 Pedersen, B., Nybø, S. and Skarpaas, O. 2013. Ecological framework for the Nature Index. A 223 more rigorous approach to the determination of reference values and selection of 224 indicators. - NINA Minireport 442. 28 pp 225 Rockström, J., W. Steffen, K. Noone, Å. Persson, F. S. Chapin, III, E. Lambin, T. M. Lenton, M. 226 Scheffer, C. Folke, H. Schellnhuber, B. Nykvist, C. A. De Wit, T. Hughes, S. van der Leeuw, 227 H. Rodhe, S. Sörlin, P. K. Snyder, R. Costanza, U. Svedin, M. Falkenmark, L. Karlberg, R. 228 W. Corell, V. J. Fabry, J. Hansen, B. Walker, D. Liverman, K. Richardson, P. Crutzen, and J. 229 Foley. 2009. Planetary boundaries:exploring the safe operating space for 230 humanity. Ecology and Society 14(2): 32. [online] URL: 231 http://www.ecologyandsociety.org/vol14/iss2/art32/ 232 Rockström, J.; Steffen, W.; Noone, K.; Persson, Å.; Chapin, F. S.; Lambin, E. F.; Lenton, T. M.; 233 Scheffer, M.; Folke, C. 2009b, "A safe operating space for humanity", Nature 461 (7263): 234 472–475. 235 Saltelli A, Ratto M, Andres T, Campolongo F, Cariboni J, Gatelli D, Salsana M, Tarantola S (2008) 236 Global sensitivity analysis - The primer. Wiley 237 SENPLADES (Secretaría Nacional de Planificación y Desarrollo), 2010. National Plan for Good 238 Living 2009-2013. English summary available at : http://www.planificacion.gob.ec/wp- 239 content/uploads/downloads/2012/08/versi%C3%B3n-resumida-en-ingl%C3%A9s.pdf 240 Simmons, C., Kevin Lewis, and John Barrett, 2000. Two feet-two approaches: a component- 241 based model of ecological footprinting. Ecological economics, 32(3), 375-380. 242 Steffen, Will, Katherine Richardson, Johan Rockström, Sarah E. Cornell, Ingo Fetzer, Elena M. 243 Bennett, R. Biggs, et al. 2015. “Planetary Boundaries: Guiding Human Development on a 244 Changing Planet.” Science, 1259855. 245 Ulanowicz, R.E. 1996. Trophic flow networks as indicators of ecosystem stress. pp. 358-368, In: 246 G. Polis and K. Winemiller (eds.), Food Webs: Integration of Patterns and Dynamics. 247 Chapman-Hall, New York. 248 van den Bergh,J., and Fabio Grazi, 2015, Reply to the first systematic response by the Global 249 Footprint Network to criticism: A real debate finally?, 250 http://dx.doi.org/10.1016/j.ecolind.2015.05.007 251 Wackernagel, Mathis, Gemma Cranston, Juan Carlos Morales, Alessandro Galli, 2014. “Chapter 252 24: Ecological Footprint Accounts: From Research Question to Application,” Giles 253 Atkinson, Simon Dietz, Eric Neumayer and Matthew Agarwala (eds.), 2014, Handbook of 254 Sustainable Development: second revised edition. Edward Elgar Publishing, Cheltenham, 255 UK ISBN-13: 978-1782544692 256 Wackernagel, M, 1991. "Land Use: Measuring a Community's Appropriated Carrying Capacity as 257 an Indicator for Sustainability"; and "Using Appropriated Carrying Capacity as an 258 Indicator, Measuring the Sustainability of a Community." Report I & II to the UBC Task 259 Force on Healthy and Sustainable Communities, Vancouver. 260 Wackernagel, M., Rees, W.E., (1996). Our Ecological Footprint: Reducing Human Impact on the 261 Earth. New Society Publishers: Gabriola Island, Canada.

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262 Wackernagel, M., “Ecological Footprint and Appropriated Carrying Capacity: A Tool for Planning 263 Toward Sustainability.” 1994. Ph.D. Thesis. School of Community and Regional Planning. 264 The University of British Columbia. 265 http://circle.ubc.ca/handle/2429/7132; http://circle.ubc.ca/bitstream/handle/2429/71 266 32/ubc_1994-954027.pdf?sequence=1 267 Wackernagel, M., Schulz, B., Deumling, D., Linares, A.C., Jenkins, M., Kapos, V., Monfreda, C., 268 Loh, J., Myers, N., Norgaard, R., Randers, J., 2002. Tracking the ecological overshoot of 269 the human economy. Proc. Natl. Acad. Sci U.S.A. 99 (14), 9266–9271. 270 Weinzettel, Jan, Kjartan Steen-Olsen, Edgar G. Hertwich, Michael Borucke, and Alessandro Galli. 271 2014. “Ecological Footprint of Nations: Comparison of Process Analysis, and Standard 272 and Hybrid Multiregional Input–output Analysis.” Ecological Economics 101 (May): 115– 273 26. doi:10.1016/j.ecolecon.2014.02.020. 274 Whitby, A., Seaford, C., Berryal, C., 2014. ‘BRAINPOoL Project Final Report: Beyond GDP – From 275 Measurement to Politics and Policy’. BRAINPOoL deliverable 5.2, A collaborative 276 programme funded by the European Union’s Seventh Programme for research, 277 technological development and demonstration under grant agreement No. 283024. 278 Available at: http://www.brainpoolproject.eu/wp- 279 content/uploads/2014/05/BRAINPOoL-Project-Final-Report.pdf 280 Wijkman, A. and Rockström, J. (2012) Bankrupting Nature: Denying Our Planetary Boundaries A 281 report to the Club of Rome, Routledge. 282 283 284 285 286 287 288 289 290 291 292 293 294

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Table 1 by Lin, Wackernagel, Galli and Goldfinger: Comparing the footprint accounts with similar approaches

Mass Flow Analysis Footprint and Carbon Concept Planetary Boundaries (also called ‘material WAVES/Genuine Saving Inclusive Wealth HANPP TEEB Biocapacity Footprint footprint’)

Organization Global Footprint Stockholm Resilience Wuppertal Institute IEA/IPCC World Bank UN University Systems Ecology - Austria UNEP s Network Centre

How much of the What are planetary How much mass How much How much net wealth How much wealth is in How much net primary What is the

regenerative capacity of boundaries, and for each moves through an CO2 from does a country have? a country? How does it production is economic value What the biosphere is one of them, how close is economy? fossil fuel is How does it change year change year to year? appropriated by human of ecosystem research occupied by human humanity to those limits? released to year? (focus on natural economies from the services? question is demand? (Plus, where within a capital) ecosystems within their being does demand originate, country? Also region? answered? and how is the by a lifestyle biocapacity distributed or activity. on the planet? In the 21st century, Makes a scientific global More mass flow is a Future Is overall wealth Is overall wealth How intensively are they How big are biocapacity is case for a number of proxy for the overall climate (measured in monetary (measured in using their own ecological increasingly a limiting dimensions. Adds amount of resource treaties value) building up per monetary value) ecosystems? Higher benefits How is this factor for the human credibility to the possibility being used. could put a capita? If not, this is a risk building up per capita? usages, in combination compared to question economy. It is essential of global overshoot. May limitation on to income generation in If not, this is a risk to with high net imports, put economic relevant to to know how much you not be easily applicable at this emission, the future. income generation in countries at risk. High benefits? Are understandin have, how much you local scale. Not clear what through the future. usages could also lead to there hidden g a country's use, and what the trends trade-offs are among prices, or degradation. costs that (or other are. boundaries. regulations. overshadow entity's) risk To set targets benefits? Are and and monitor there both opportunity progress, economically exposure? metrics are and ecologically needed. better options for development? Metric global hectares kg/yr / kg/yr kg/year kg/year $ $ kg biomass/year $/yr

Key websites www.footrpintnetwork.o www.stockholmresilience.o www.wupperinst.org www.Ipcc.ch www.wavespartnership.o inclusivewealthindex.o http://www.uni- www.teebweb.o

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rg rg www.materialflows.n Hertwich and rg rg klu.ac.at/socec/inhalt/1.ht rg Wackernagel et al. 2014 Rockström et al 2009 et Peters 2009 see website for reports m see website for Fischer-Kowalski see website for reports Krausemann et al 2013 reports et al. 2011 Provides the bottom-line Each one of the planetary Kg easy to There is a Dollars speak loudly to Dollars speak loudly to Biophysical assessment. Powerful case answer to a central boundaries can easily be understand, directly scientific traditional economic traditional economic stories. question: Is there communicated and are links to tracked mass effort behind analysts. analysts. Applicable to enough biocapacity to known to most publics. Can flows of categories. carbon business and maintain the metabolism build on independent accounting. policy contexts. Strengths of the economy? Area is robust scientific Some statistical Public is relatively easy to assessments in each offices now track starting to be understand - it is like a domain. mass flows. more farm. Has been tested by sensitive to 12 national basic climate governments. science.

Many details could be Some boundaries are Mass flow accounts CO2 in Dollars are unstable Dollars are unstable Tool cannot establish Not

improved beyond the global (CO2), others are are at the basis of isolation is predictors of the future. predictors of the clear ecological limits to comprehensive current accounts that local (water, nitrogen). Footprint accounts. hard to Prices can fluctuate by future. Prices can demand. Does not deal yet. Also mostly use 6,000 data points Difficult to understand But it is less clear tackle since magnitudes. They only fluctuate by with trade. based on per country and year. trade-offs among them. what question they self-interest show current human magnitudes. They only financial value The accounts, however, Difficult to apply at sub- answer. One kg of for those preferences in the show current human assessments. are constantly being planetary scale. gravel has different reducing market, not ecological preferences in the refined. There is demand on nature their necessities. market, not ecological currently no direct link to than one kg of wood. emission is necessities. Results are financial figures, which (Apart from weight, not obvious counterintuitive, and makes it harder to in what way are they or may be suggest that natural communicate to finance ecologically equal?) absent. Just capital has extremely Weaknesses oriented audiences. How do mass flows focusing on low value.

However, numbers can link to supply? Which CO2 may be interpreted for them. mass flows are detract from included and which all other ones not, and why? environment While having good al pressures. material statistics is fundamental, result interpretation (or how to use them to guide policy) is not as obvious.

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