Emission Impossible Ltd


Air pollution is much worse than we thought

Ditching fossil fuels would pay for itself through clean air alone.

The evidence is now clear enough that it can be stated unequivocally: It would be worth freeing ourselves from fossil fuels even if global warming didn’t exist. Especially now that clean energy has gotten so cheap, the air quality benefits alone are enough to pay for the energy transition.

This conclusion has been reaffirmed by the latest air quality research, presented at a recent hearing of the House Committee on Oversight and Reform by Drew Shindell, Nicholas professor of earth science at Duke University (and a lead author on both recent IPCC reports).

Shindell’s testimony reveals that the effects of air pollution are roughly twice as bad as previously estimated.

“The air quality scientific community has hypothesized this for at least a decade, but research advances have let us quantify and confirm this notion, over and over,” says Rebecca Saari, an air quality expert who teaches in civil and environmental engineering at the University of Waterloo. “The air quality ‘co-benefits’ are generally so valuable that they exceed the cost of climate action, often many times over.”

If the numbers are shocking, it’s because the science has been developing rapidly. First, says Shindell, “there’s been a huge upsurge in work in developing countries, in particular China,” which has produced larger data sets and a wider, fuller picture of the real-world effects of exposure.

Second, where scientists used to focus almost exclusively on pollution effects for which there is an established and well-understood biological pathway, the recent production of enormous data sets (for instance, the entire population of more than 60 million Medicare patients) has allowed them to uncover new statistical correlations.

With giant data sets, “you can control for socioeconomic status, temperature, hypertension and other existing conditions,” and other variables, says Shindell. “You can convincingly demonstrate that correlation is in fact causal, because you can rule out essentially every other possibility.”

For example, scientists now know that exposure to smog (tiny, microscopic particulates) hurts prenatal and young brains. Even though they don’t yet fully understand the biological mechanism, they know it reduces impulse control and degrades academic performance. Similarly, they know it hurts the kidneys, the spleen, even the nervous system.

“The well-understood pathways, things like strokes, lower respiratory infections, and chronic obstructive pulmonary disease, only seem to capture about half the total,” Shindell says. “When you look at the [new] studies, you find that air pollution seems to affect almost every organ in the human body.”

“About twice as many people die in total as die just from the pathways we understand,” says Shindell. “We’ve been underestimating all along.”

While that may sound like a big jump, it is likely a lower bound. On both air pollution and climate change, the study omitted many effects that “are clearly present but cannot yet be reliably quantified.” The true numbers are almost certainly higher.

New air pollution research ought to break the climate policy logjam

Climate change has often been framed as an intractable problem for international coordination, a matter of shared sacrifice, with every country incentivized to be a “free rider,” reaping the benefits without taking on any of the costs.

But the latest air pollution research, coupled with the plunging cost of clean energy, should render that dynamic moot.

It is true that climate change can only be averted with the entire world’s cooperation; if the US reduces its emissions to net zero but the other countries of the world (especially China and India) continue on their current trajectory, it will make almost no difference in temperature. The health benefits of avoided severe heat will not manifest.

However — and this is the crucial fact — the air quality benefits will manifest, no matter what the rest of the world does. Shindell’s team ran a version of their scenario in which the US came into compliance with a 2°C pathway but the rest of the world continued with current policies. “We found that US action alone would bring us more than two-thirds of the health benefits of worldwide action over the next 15 years,” Shindell testified, “with roughly half the total over the entire 50-year period analyzed.”

The air quality benefits arrive much sooner than the climate benefits. They are, at least for the next several decades, much larger. They can be secured without the cooperation of other countries. And, by generating an average of $700 billion a year in avoided health and labor costs, they will more than pay for the energy transition on their own. Climate change or no climate change, it’s worth ditching fossil fuels.

And if this is true in the US — which, after all, has comparatively clean air — it is true tenfold for countries like China and India, where air quality remains abysmal. A Lancet Commission study in 2017 found that in 2015, air pollution killed 1.81 million people in India and 1.58 million in China.

Air pollution ought to be seen as a global civil rights crisis

The extraordinary level of suffering humanity is currently experiencing from air pollution is not necessary for modernity; it could be reduced, at a cost well below the net social benefits, with clean energy technologies on hand.

If they are not necessary, then the millions of lives ended or degraded by fossil fuels every year are a choice. And when suffering on this scale, that is this brutally inequitable, becomes a choice, it enters the same ethical terrain as war, slavery, and genocide. The effects are more distributed over time and geography, as are the decision-making and the moral culpability, but the cumulative impact on human well-being — on our longevity, health, learning, and happiness — is comparable, and every bit as much worth fighting.

[Abridged: Vox]