Ecological footprint

An ecological footprint is an indicator that measures how big an area of productive land and water is needed to produce the resources we require to maintain our standard of living. Oslo has calculated its ecological footprint.

Summary.
The Western Norway Research Institute in Sogndal and ProSus, at the Centre for Development and the Environment, University of Oslo, have carried out a project for Oslo municipality to measure the size of the city's Ecological Footprint as a result of current levels of consumption. A calculation model was developed for use in municipal reporting and administrative procedures, and also a net-based "footprint-calculator" was developed so that the public can calculate their own personal Footprint.

The project's background can be divided into three parts: (1) Auditing of the city's "ecological programme" and the development of a new State of the Environment Report for Oslo; (2) the municipality's work on Local Agenda 21 and (3) the municipality's participation in the "European Sustainable Cities & Towns Campaign".

An Ecological Footprint is an indicator, or analytical tool, that uses the biologically productive area as its basic unit of measurement. The Footprint provides a figure of the amount of productive land and water area required (hypothetically) to produce the resources and the sink capacity needed to maintain a given standard of living.

The following categories of biologically productive area are used when measuring the Ecological Footprint:

1. Land area necessary to protect biological diversity

2. Bioproductive land area, using the following three sub-categories:  a)crop land, b)grazing land, c) forest land

3. Bioproductive water area

4. Land area for housing

5. Land area necessary for consumption (binding) of energy

The last category concerns the hypothetical area of forest that would be required to absorb the CO₂ emissions resulting from energy consumption. The method does not take into consideration reforestation as a measure to remedy climate change, but converts to forest area in order to illustrate the hypothetical requirement of land area that ensures the possibility of comparison with other types of consumption.

The Worldwide Fund for Nature (WWF) publishes at regular intervals a calculation of the global Ecological Footprint and national calculations for roughly 150 countries. The last calculation was carried out in 1996. The calculations are made using 175 consumption categories based on (largely) trade statistics. Since it is very problematical to carry out such comprehensive calculations for a single municipality, we have, in our work for the municipality, concentrated only on those categories of consumption we consider most important when computing a local Ecological Footprint. Several separate sources emphasise the importance of the consumption of: (1) food, (2) energy due to transport, and (3) consumption related housing. We have used this three-part classification as a starting point when selecting the data needed to carry out our calculations.

The three main categories of consumption data, with four subgroups of the most important category, household consumption, are:

1) Local production (emission of greenhouse gasses from public and private sectors; land area employed for public and private sector buildings; and electricity consumption by public and private sector' buildings).

2) Household consumption

• Consumption of food

• Housing-related consumption (land area, bound energy in furniture and housing, consumption of timber for construction, energy consumption for heating etc.)

• Energy consumption of transport

• Consumption of goods (clothes, shoes, leisure services and goods, paper)

3) Local treatment of waste (land area consumption of waste incineration facilities, emission of climate gasses from landfills, reduction in climate gasses emission due to waste-based energy production)

In the calculation of the Ecological Footprint for Oslo, we have, as far as possible tried to base our investigation on genuine local data. We have managed to obtain such data for 20 percent of the calculated Footprint. For the remaining data we have had to base our calculations on national consumption figures, which we have attempted to adjust in different ways so as to reflect the conditions in Oslo more closely. The most important method for these adjustments has been to use the Consumer Survey carried out by Statistics Norway, which provides figures for a number of consumption categories. In the survey, independent figures are also given for Oslo (and Akershus), making it possible to adjust some of the national consumption figures.

Our calculations show that each Oslo inhabitant has an Ecological Footprint of roughly 80,000 m², or the equivalent of 11 soccer fields. In total, Oslo's population, through their consumption, exploits roughly 4,000,000 hectares of biologically productive area, or 90 times the municipality's total land area. If the world's population had a similar consumption, we would need 3 extra planets to live on. Globally, there is roughly 2,180 m² of biologically productive area per capita.

The consumption of food represents by far the largest component of Oslo's Footprint, exactly one half of the total. The other large components are transport emissions and consumption related to housing. The Footprint linked to emissions from air transport alone represents 14 percent, while the consumption of timber for housing construction represents 8 percent. The consumption of energy-binding land area of over 50 percent represents the largest area category of the total Footprint, underlining the importance of reducing emission of climate gasses.

Measures for recirculation and energy recovery from waste is in itself an important environmental measure, but affects only to a small extent the Footprint calculation. The treatment of waste represents only a small fraction of the total Footprint, so although our calculations have shown that various measures have halved the Ecological Footprint in relation to waste, this has only resulted in an overall reduction of 1 percent. This illustrates that the real problem is the volume of waste, rather than the method of waste treatment. For example, the inhabitants of Oslo throw away about ¼ of their food. If one could reduce this amount by half, there would be a reduction in the Footprint of more than 10 percent. Such a measure would be ten times more effective in reducing the Ecological Footprint per capita than the measures implemented for the treatment of waste.

The Footprint for Oslo is roughly 13 percent lower than the national average, although the Oslo population has a higher consumption than the national average with respect to several important areas:

• 60 percent higher Footprint for air travel
• 5 percent higher Footprint for food

However, the four areas where the Ecological Footprint per capita is considerably smaller in Oslo than the national average more than compensate for these higher figures:

• Oslo is a "de-industrialised" city with a 74 percent lower Footprint from emissions of greenhouse gasses from industry.
• Oslo uses 47 percent less timber in building construction than the national average.
• Oslo has lower car ownership, which gives it a 17 percent lower Footprint in relation to private car transport.

If we only consider household consumption, and don't count local production and local waste processing, the difference between the national average and Oslo is reduced to a margin of only 1 percent lower for Oslo. In other words, the gains Oslo has from a lower per capita living-area (lower consumption of timber and bound energy in housing) and lower private car ownership (lower consumption of private car transport) is significantly cancelled out by a considerably higher consumption of air travel and food.

Footprint calculations have been carried out internationally for a number of towns and cities, but the results can only be compared to a small extent, because of the large variations in how the calculations have been made. We have compared the following towns and cities: Vienna, London, the Hague, Malmö, Kuopio, Helsinki, Toronto and Santiago de Chile. We have attempted to make a comparison in the report, using the national Footprints for those towns that have employed methods very different from our own. In addition, we have also included Denmark and Portugal. The comparison shows that Oslo's Footprint coincides to a great extent with the national Footprints of Great Britain, the Netherlands, and Austria. The Footprints of Malmö in Sweden, and of Finland, Denmark and Canada are all slightly larger than Oslo's. Austria and Portugal have, to some extent, a smaller Footprint than the other European countries, whereas Chile's Footprint is, predictably, about half that of the industrialised countries. Given that there currently exists no common method for the calculation of local Footprints, it is very difficult to say anything conclusive about the local variations. We can, however, point out some more general relations, based on the differences in living standards, natural conditions and the extent of town density.

The most effective measures for reducing the Ecological Footprint are those aimed at the classifications mentioned above: food, transport and housing. In relation to the consumption of food, there are three strategies that emerge as being relevant for local initiatives:

• Locally grown food that is sold and consumed close to the place of production to reduce transport.
• More wild fish and vegetables, i.e. less use of food types which leave a larger Ecological Footprint - such as dark meat and farmed salmon.
• Ecologically labelled food; i.e. increased sale of DEBIO labelled food, wherever this is possible.
• Reduction in the throwing away of food; home composting is also good but not as effective.

Concerning transport, the following are important:

• Reduction in the use of air travel abroad: Oslo has a much higher consumption of air travel than the national average. Increased use of videoconferences and choice of holiday destinations that do not include air travel.
• Reduction in private car ownership: Oslo has a relatively low per-capita figure compared with the national average.
• Reduction in leisure driving: gains in low per-capita car ownership are cancelled out partly by the high level of leisure driving.
• A strengthening of public transport, which should probably be combined with restrictions on private car transport, if it is to have full effect.

We have not included the transition from petrol and diesel to alternative fuels. Although the use of these can result in lower emissions, several of these fuel types involve increases in land use related to the production of energy.

Concerning housing, and housing related consumption, one condition emerges as being important: consumption is largely related to the size of the living area. Firstly, due to the house's original base area. Secondly, a larger living area will normally result in a higher energy consumption of energy from heating, and from the greater amount of furniture and household articles etc. Thirdly, the size is related to the consumption of timber needed in construction and maintenance of the housing unit.

Simple energy calculations often show that the operation of a housing unit represents 90 percent of the total impact on the environment. Interestingly, our Footprint calculations show this relation to be roughly 40:60, with the difference primarily due to the consumption of timber used in construction. The Footprint calculations highlight an important point in that a large living area is in itself an expression of a high consumption of resources, at the same time that it is an indication of high consumption due to the operation of the housing unit. Land-use planning and other forms of regulation which include smaller living areas per capita will consequently result in a long-term effect in the form of reduced consumption of resources in both the construction and operation of housing units. In the year 2000, the average size of new housing units in Oslo was 123 m² compared to the national average of 144 m². The consumption of living area in Norway has increased by 43 percent in the last 20 years, and the average living area per capita is roughly 25 percent larger in Norway than in similar industrialised countries.

More detailed Footprint analyses show that housing density, distance from the city centre, and the type of housing unit determine the total Footprint of the separate households. Such analyses provide a basis for discussing the different models for sustainable towns. On the one hand, there are those who propose that relatively dense housing patterns, with a low percentage of detached houses, result in a lower per-capita consumption. Such compact towns, it is claimed, not only satisfy the principles for energy-saving physical planning, but also generally match up with the demands of sustainable development. On the other hand, there are those who propose a relatively open town structure: green towns, involving the development principle of a potential reduction in the circulation of local resources. Our calculations suggest there is a basis for promoting a decentralised concentration as a profitable compromise between the two models. Such an approach involves support for establishing compact "mini-towns", in this context, within the borders of Greater Oslo (Stor-Oslo). Such "mini-towns" are characterised by:

• High utilisation of land area so that public and private services are within the reach of pedestrians and cyclists.
• Mixed land-area use so that offices, shops, and business and trade activities, and public and private services are integrated into the housing area.
• Limited traffic and parking areas with a strong emphasis on securing a pedestrian and bicycle net.
• Central nodes for public transport (rail, underground or bus stations), and a well-developed public transport connections for commuting.
• Proximity to public services such as schools, libraries, welfare centres and nurseries etc.
• High degrees of self-sufficiency locally in order to meet daily needs.
• Public spaces with a large emphasis on design (fountains, street furniture, street courtyards etc.).

It might be said that this is already an integral part of Oslo's planning and development. It should be of interest, however, that the calculations of the Oslo Project confirm the environmental good-sense in such a strategy.

The report illustrates the difficulty of documenting variations between local communities in different countries. There is a clear demand for a common type of data if international comparisons are to be carried out. National averages have to be used to a great extent, but these may only be adjusted slightly to reflect local conditions. It is simpler to show variations within a country, in which case it is easier to have control over the use of similar methods and equal access to data. Yet, it is still an open question concerning how large the variation is. We have shown a variation in the figures for Oslo and the national average of 13 percent. Where the variation is clearest, however, is on the level of the individual. Figures from Oslo provide examples of variations close to a factor of 100:1. Although the use of the Footprint is less relevant as a tool for comparison between municipalities internationally - perhaps also nationally - the tool may nevertheless be of use to municipalities in the following three ways: Comparisons over time of figures for the whole municipality; more limited sector evaluations; and individual calculations.

The potential usage of the Ecological Footprint's is largely determined by the characteristics of the methodology. We have evaluated the method based on three factors: the type of information to be provided; the intelligibility of the information; and the user-friendliness of the tool. On the basis of these criteria, we suggest that the technique may be of use in municipal policy in the following contexts:

• "Directional analysis": evaluation of the direction of change and innovation in annual reports or other regular rolling plans/programs.
• Administrative procedures: impact studies - primarily in relation to larger construction development plans.
• Teaching and public debate: a net-based "test yourself" Footprint calculator has been developed which offers Oslo's pupils, students and inhabitants in general the opportunity to calculate their personal Footprints.

It is important to emphasise that Ecological Footprint calculations should not be used instead of, but in addition to, evaluations and analyses that already are being carried out. It is difficult to include environmental problems linked to hazardous chemicals, heavy metals and radioactive material in Footprint calculations with the method as it is used today. The same is also true with respect to the overall quality of the environment. Neither water consumption nor the relation between health and the environment are included in the Footprint calculation.

The Footprint thus needs to be supplemented by other indicators, if it is to be an adequate tool for dealing with sustainability problems in municipal policy. The use of the Footprint can introduce new perspectives into the environmental debate: partly by focusing on the environmental consequences of consumption (in addition to problems related to production), and partly by introducing new themes into environmental policy (e.g. 'food'). It can also be used to reinforce focus on themes that are already part of the environmental policy agenda (e.g. 'transport', and especially 'air travel'). It seems apparent that the Ecological Footprint calculations can contribute to enlarging the environmental policy agenda, in relation to the traditional focus of Norwegian municipalities, which tend to emphasise themes such as: water; sewage and refuse collection; green structures; local air pollution; outdoor life and other forms of local environmental problems and challenges. The local agenda can also be linked to global environmental policy in two ways: global environmental problems can be made local by linking consumption of biologically productive area on a global basis to local consumption. The local consumption can then in turn be linked to a just distribution of material benefits globally, by relating the local Footprint to a concept of global equity related to equal quotas for the appropriation of bioproductive land and water use.