06 November 2012

Measuring how clean and green New Zealand is

This blog post was written by postgraduate student Stephanie Heinicke as part of the course, Research Methods in Ecology (Ecol608). Stephanie is one of three students that revisits a Lincoln University research area on calculating the ecological impact of New Zealanders published in the late 1990s.

New Zealand markets itself as a clean and green country. In a study commissioned by the Ministry for the Environment, it was estimated that this image is worth hundreds of millions of dollars. This is how much New Zealand would lose if international consumers would start to think of this country and its products as not being clean and green.

But how clean and green is New Zealand? And how can it be measured?
An often used approach to assess the sustainability of consumption and production patterns of a country is the ecological footprint. This method calculates how much productive land area is needed to provide all the stuff a person consumes, like food, clothes, and housing as well as how much area is needed to generate energy and to absorb all the waste. This can be calculated for an individual, a community and also a country. When comparing these numbers with the land that is actually available, it gives an idea of how sustainable a lifestyle is.

The area needed to produce everything we consume: food, goods and services, housing, energy, ... Graphic by Institut Escola Les Vinyes

Calculating the ecological footprint on a national scale is quite challenging. An awful amount of data is needed to represent the different factors that make up the ecological footprint. But an indicator is only useful when it can be compared for different countries and through time. So in 1998 Kathryn Bicknell and her colleagues from Lincoln University came up with a method for calculating the ecological footprint from data that most developed countries routinely collect as part of their national accounts. Such data includes for instance how much each economic sector produces. This method uses a form of input-output analysis which basically considers how different aspects of an economy interact and the effects an economy has on the environment. Since its publication 14 years ago, this method was further developed to a standard suitable to calculate the ecological footprint for Australia and also to estimate the ecological footprint of international trade activities.

Coming back to our initial question: how clean and green is New Zealand? Bicknell and her colleagues found that the ecological footprint of New Zealand is 3.49 ha per person. When exempting the land needed to produce export goods, New Zealand is one of the few developed countries that have enough land to cover its consumption requirements. This is not necessarily due to the fact that Kiwis are more sustainable in their consumption patterns but, rather a result of the low population density.

This becomes clear when looking at the per capita land requirements. As this is a new methodology, it is not directly comparable to earlier numbers but it does resemble estimates from other developed countries. Bicknell and her colleagues concluded that the ecological footprint of New Zealand is noticeably smaller than the ones of the USA and Canada, but it is bigger than the one of the Netherlands. And it is far bigger compared  with countries such as India.

In the end, this reinforces earlier perceptions. Yes, New Zealand is cleaner than some other developed countries. But if everyone lived like a Kiwi, we would need more than three planets. That can hardly be called a sustainable lifestyle. This brings us back from the abstract level of countries to each individual. The lifestyle choices we make have direct effects on the environment. If you want to find out how big your own ecological footprint is, go to one of the online ecological footprint calculators – try this one! And maybe more importantly – find out how you can reduce it.

This article is based on:
Bicknell, K.B., Ball, R.J., Cullen, R. and Bigsby, H.R. 1998. New methodology for the ecological footprint with an application to the New Zealand economy. Ecological Economics 27: 149-160.

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