A4.15.1 Limitations of Footprinting


The Ecological Footprint is not a precise measure of ecological sustainability. While it is perhaps the best estimate to date, it is important to recognize its limitations. In general, the Footprint underestimates the impact of human activities on the biosphere. Any applications of the Footprint methodology must keep this perspective in mind. Because it focuses on renewable resources, the Footprint provides limited information about most non-renewable resources and their impact on ecosystems (with the exception of fossil fuel impacts which it partially addresses).


The concept of “global hectares” of world average bioproductivity is useful for looking at issues related to global Footprint. But individual applications refer to specific locations where there is an impact. These local areas may have bioproductivity rates different from the global average; where available, local data can be used. Another limitation is that the approach allows only general types of bioproductive areas to be identified (e.g. cropland, forests, etc). Specific ecosystems within these areas are not addressed. These limitations do not invalidate the Footprint, but do underline the importance of interpreting any specific application with these limitations in mind.


Other limitations include:

  • At present the ecological footprint does not consider the oceans and underground resources including water.
  • As currently constructed, the ecological footprint is a static measure.
  • Eco-footprints do not account for:
    • Any economic, political or cultural factors such as well-being.
    • 78% of the surface of the earth, which is deemed to lack any biocapacity (deep oceans, deserts, mountains).
    • Water and waste (except insofar as they affect the biocapacity of a region and so show up by those proxies).
    • Non-renewable resources and their depletion, only renewable resources in the biosphere. The exceptions are where they affect the biosphere, for example pollution from mineral mining reducing the biocapacity of a fishery;
    • Biodiversity, toxicity, pollution and other traditional environmental concerns;
    • Unsustainable management of the biosphere, for example clear-cutting a rainforest for agriculture would seem to increase biocapacity because the yield factor of cropland is higher than that of forestry;
    • Related to the above point, destruction of biocapacity by long-term processes such as climate change;
    • The true use and exchange value of different land types, for example forestry doesn’t include the pharmaceutical potential of the species that live there;
    • Methane and other greenhouse gases, only carbon dioxide;
  • Quality of data.
    • The accuracy of any given footprint analysis is also constrained by the quality of the data. The granularity of most data is very low, and the error margins quite high, so in general footprints are deemed to have an error margin of around 20-30%. Whilst the UK has exceptionally good data on the input/output economic flows, breaking it down into over 160 categories, for most countries it’s around 40 categories making translations from industry to materials very rough-and-ready.
  • Assumptions behind the data.
    • For example, there is data for a variety of different kinds of cropland in the UK, but this still misses regional variations, the crops we might need to fulfil dietary requirements, and the crops we need to meet a reasonable demand profile for a wider area including exports to the continent. Imagine Japan, which is completely dependent upon imports of most raw industrial materials, and one can see how a footprint might mislead us into thinking Japan is totally unsustainable even if the trade relations with surrounding countries is in fact genuinely sustainable.


Because of these limitations, ecological footprinting should be used as one tool amongst many. It is excellent at providing an overview of global, national and regional resource use, producing headline figures.