Key words :
ozone layer depletion,
Where Ecological Footprints Fall: Poor Nations Fare Badly
18 Feb, 2008 01:05 pm
In the past 50 years, human society has rapidly transformed the environment at a dizzying pace, and poor nations have been made to bear a disproportionate portion of the costs, reports a new study on the distribution of and responsibilities for ecological harm among nations.
For each category, the authors first estimate how the costs may be shouldered by low- (L), middle- (M), and high-income (H) nations, using income categories from the World Bank (H: U.S., E.U., Japan, etc.; M: China, Brazil, Russian Federation, etc.; L: India, many African nations, etc.). Second, the researchers quantify how activities by each of the income groups could have directly or indirectly caused the damages. For example, the researchers assign responsibility for climate change and ozone depletion impacts according to each group’s greenhouse gas and chlorofluorocarbon emissions over 1961-2000, respectively. To analyze agriculture, deforestation, overfishing, and mangrove loss, they attribute responsibility for the costs based on where the related goods were finally consumed, e.g. overfishing costs are assigned based on seafood consumption.
The researchers scoured the literature for highly-regarded and methodologically sound cost estimates for the environmental damages. To arrive at such price tags, environmental economists use a variety of techniques to find out what people are willing to pay for the ecosystem service or avoid the loss in the first place. For climate impacts, the researchers applied estimates from 5 well-known models that predict the impacts over the next century. The authors then paired these cost estimates with the most complete and accurate datasets available for environmental change and human activity (e.g. from the UN Environment Program, the World Resources Institute, the Sea Around Us Project, etc.).
The costs they present are dramatic. For just 40 years of only a subset of human activities, the world may bear damages of up to $47 trillion (net present value, 2005 international $). For comparison, the GDP for the entire world in 2006 was $58 trillion.
The authors give several reasons why the estimate may be conservative. They only tallied damages from activities over 1961-2000 even though substantial degradation occurred earlier and has continued since 2000, and they didn’t consider important sources of costs like industrial pollution. Nor could they include the costs of biodiversity losses in their estimates.
Given the uncertainties involved, the researchers underscore the distribution of costs and responsibilities rather than the particular values. Their study is the first to create a map of where the ecological footprints of country groups are falling. Specifically, they find that damages from climate change and ozone depletion for the poorest group of nations have been overwhelmingly driven by emissions from the rest of the world. They also uncover a stark pattern for overfishing, showing that the seafood derived from the depleted fish stocks in low-income country waters is ultimately consumed by the rest of the world. In addition, they point to the destruction of mangrove forests as a striking case study. Low- and middle- income nations bear the storm damages from converting their mangroves to shrimp farms, while nearly all of their exports go to the rich group. Indeed, damages caused by the actions of rich nations may cost poor nations more than the latter’s combined foreign debt.
There are necessarily large sources of uncertainty in an analysis of this kind, the authors acknowledge. Yet demands on nature’s services are only expected to intensify over the next half-century. Whatever the exact costs may be, the authors argue that environmental inequities for the poorest countries are real. They hope their study can spark a lively discussion reframing the environmental responsibilities between nations and the true costs of human activities.
Since the costs estimated in the study are not included in market prices (“external costs”), the study can also help raise awareness among consumers. The loss of the next generation of fish is not included in the price of a plate of sushi, nor do storm damages figure into the cost of shrimp at the supermarket. Perhaps we may see labels like “seventh generation fish” or “mangrove-safe shrimp” in the future.
U.T. Srinivasan et al. “The debt of nations and the distribution of ecological impacts from human activities,” Proceedings of the National Academy of Sciences. 22 January 2008. Abstract available here.
Key words :
ozone layer depletion,
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Comment by EM
26 Feb, 2008 12:02 pm
The factors for estimating GDP by international economic organizations like the World Bank etc. should be reconsidered to fit reality of situations in developing nations-- and indeed, even in the purported developed nations.