Half the World Still Breathes Polluted Air

The latest Yale Environmental Performance Index reports that 3.5 billion people still live in places with unsafe pollution levels.

Image REUTERS/B Mathur
Smog cover New Delhi, Indian on November 14, 2012. (REUTERS/B Mathur)

Global leaders gathered at the World Economic Forum in Davos last week to jostle over whose economy is booming the most. But they’re also competing in a newer ranking: who takes the best care of their environment.

For the past 15 years, Yale and Columbia University researchers have been tracking what they call the Environmental Performance Index—a biennial, data-intensive ranking of how well 180 countries protect the health of their populations and ecosystems. Finland topped the list this year, followed by Nordic compatriots Iceland, Sweden, and Denmark. The bottom included weak and failing states like Somalia, Eritrea, Afghanistan. The U.S. clocked in at 26.

Overall, the EPI shows major improvements in worldwide access to safe water but paints a dire picture of air pollution: 3.5 billion people, more than half of humankind, live in areas where air pollution exceeds the safe level designated by the World Health Organization.

“We like to call it the tale of two indicators,” says EPI report author Angel Hsu, a professor of forestry and environmental studies at Yale. “Over the past decade the global community has achieved success in reducing the number of people dying from unsafe water, but we have not been achieving those same results in air pollution. Air pollution has gotten worse and more people are dying from air pollution.”

(Yale EPI)

Hsu credits the United Nations “Millennium Development Goals,” which guided development policy from 2000 to 2015, with targeting unsafe drinking water with clear goals and monitoring; the number of people lacking access to clean water has plunged from 960 million to 550 million since 2000. But the findings also point to the high stakes of choosing the right indicators to track. “These global targets and indicators create these path-dependencies for collecting some types of data while overlooking others,” Hsu says.

For instance, the EPI found many countries have made tremendous progress toward the habitat protection goals set by the 1993 Convention on Biological Diversity—the global community is less than 2 percent away for both terrestrial and marine habitats. But when the EPI researchers noticed pretty huge rates of improvement since the last study, they wanted to dig a little deeper.

For the first time in the EPI, we collected and calculated indicators to see where those parks are actually overlapping with where species habitats are and what habitats species need to survive, and there’s a gap,” Hsu says. In other words, sheer land mass isn’t the best indicator for tracking the health of animal populations. In fact, nations often establish park land in marginal areas that aren’t necessarily the best for preserving wildlife, but which don’t interrupt lucrative development elsewhere.

The report also stresses the global need for additional wastewater treatment resources. The team assembled a new dataset of wastewater infrastructure using a fairly broad definition: Does a country treat any municipal, household, or industrial effluent before it gets flushed out into the environment? An astonishing 23 percent of countries failed to meet even that minimal threshold. Assisting in water treatment infrastructure for these countries should be a top development priority in the coming years.

(Yale EPI)

As may be expected, the EPI depicts very tight correlations between GDP per capita and a nation’s environmental health performance, Hsu says. But that relationship breaks down on specific measurements. For instance, wealthy European nations like the U.K., Germany, and Austria score much lower than their income bracket on nitrogen dioxide pollution, which has been linked to exhaust from diesel cars. In fact, subpar air pollution pops up in cities all over the world, developed and developing.

The rankings aren’t meant to be an end in themselves though—the goal is to spur countries to action. And that’s worked in the past. When the 2014 EPI called out India’s urban air pollution as worse than Beijing’s, it spurred international news coverage and prompted India to develop an air quality index of its own. With the UN’s new Sustainable Development Goals and the Paris climate change treaty now on the books, this centralized monitoring has an even greater potential to shape national efforts on environmental quality.

About the Author

  • Julian Spector is a former editorial fellow at CityLab, where he covers climate change, energy, and clean tech.