Photo: © Evan Parker/TNC
Eddie Game is a senior scientist for The Nature Conservancy
There is a well-recognized set of metrics to gauge the economic health of a nation, things like Gross Domestic Product (GDP). Just look up the Wikipedia entry for any country and you’ll see GDP listed right below population in the key stats section).
There has long been a search for an equivalent metric that be used to gauge the overall environmental health of a nation. This would anyone to look at the environmental performance of country overtime and also compare between countries.
There have been a few attempts at this but arguably the most well-established and recognized is the Yale Environmental Performance Index (EPI).
The EPI is a joint effort of the Yale University Center for Environmental Law and Policy and the Center for International Earth Science Information Network at Columbia University, and has been going for 15 years (in some form).
The index is designed to help governments gauge their success in addressing a wide range of environmental challenges, including impacts on human health, resource consumption, pollution, and species loss.
The most recent EPI was released with much fanfare at the World Economic Forum in Davos in January this year. Switzerland again topped the list, followed by Luxembourg and then much to my surprise, my own nation of Australia was in third spot.
Australia’s performance came as a big surprise since in 2012 (the previous EPI), we placed 48th overall, and we’ve hardly been a bastion of progressive environmental policy over the past couple of years.
Did I miss something?
Why has Australia gone from 48th place to 3rd place in two years?
Well it’s not time to ice the champagne just yet. Looking closely at the EPI reveals that Australia’s change in rank is due mainly to a change in the criteria included in the metric, rather than greatly improved environmental performance over the past two years.
The structure of the index is revised periodically both in terms of criteria and the weighting given them, and it underwent a big revision between the 2012 and 2014 editions.
These revisions are conducted by a group of experts and are done in order to maintain policy relevance, and to reflect changes in data availability and comparability across nations. This means that it is not possible to directly compare the change in ranks from past years, in theory the index should be back-casted (and they try to do this where the data allows).
So in 2012 Australia came in #48, but if we back-casted the 2014 methodology then we would have been #3 then as well.
There have been some significant changes in the criteria that have helped improved Australia’s rank. First, water resources was previously interpreted as water quantity for the environment and measured as a reduction in river flow from a natural state – Australia did poorly on this.
In the 2014 EPI, this criteria was changed (perhaps due to measurement challenges?) to simply the percentage of waste water that receives some treatment before being discharged to the environment – which Australia does very well on.
The 2014 EPI also dropped sulphur dioxide emissions as a criterion, which is something Australia had previously scored badly on. And curiously we greatly improved our score on conservation of forest resources, not because of a change in conservation policy or forest cover but because the EPI changed the reference period, what they defined as forest, and the data set used to calculate the score.
Australia has also benefited from a change in weighting of the criteria with overall greater emphasis on the link between environmental health and human health, which Australia usually scores top marks for.
Does instability equal irrelevance?
I am a huge believer of the need for an index like this, and one that is taken seriously at a national policy level.
The Yale Environmental Performance Index was certainly shaping up to have the key elements of independence and credibility needed for the success of such a metric.
However, the ephemerality in ranks that the EPI has demonstrated is a real problem for its aim of gauging environmental policy success at a national level, and therefore motivating policy change.
For example, The Nature Conservancy had been discussing with important business allies in Australia about using an improved EPI rank as a policy target for environmental sustainability. Given Australia is now close to topping the EPI the target is obviously less compelling. More importantly though, it would seem unwise for anyone to commit to a target measured by an index subject to substantial change independent of activities taken to achieve that target.
Economic indicators only work as drivers of macro-economic policy because they are stable.
In defending criticism about instability in the Yale EPI, its authors have emphasized the need to maintain policy relevance and use the best available data. These are valid concerns. The fact that entire criteria had to be removed because of changes in data availability reflects a desperate need for globally coherent environmental data.
Rather than maintain policy relevance, however, my fear is that the extent of the changes in criteria and their weights seen in the 2014 EPI will have seriously undermined the gathering strength of the EPI as a policy tool.
Opinions expressed on Cool Green Science and in any corresponding comments are the personal opinions of the original authors and do not necessarily reflect the views of The Nature Conservancy.