Cleaner Cities, Cleaner Planet

Aug 19, 2015
Originally published on August 19, 2015 6:12 am

Growing up in Brazil, I always looked up to America and Europe as standards for how to keep cities clean.

Walking along in New York or Paris, I was struck by how the streets and walkways were garbage-free — at least compared to the streets of Rio and São Paulo. I wondered what it took to do this, to convince the population that the streets and parks of a city are a space we share with others and that it is in our own self-interest — and sense of civic pride — to keep them clean.

In our time, now, the struggle is to extend this sort of attitude not only to the streets, but to the air we breathe.

Given that the air we breathe goes into our bodies, it is in our own self-interest to make sure it's as clean as possible. It should also conjure a sense of civic pride to be a banner to the world in thinking ahead — protecting not just the ground where we walk but also our breathing space from unhealthy pollution. If you live in a big city, you are aware of ozone pollution (a.k.a. smog) that can reach a "stay home" level. (Here is a list of America's top ten smoggiest cities for 2015. They are all in the Southwest.)

Things get complicated at many levels here — and not only because with air we can't just spread garbage cans around and educate people to use them. It's about how industries behave, in particular power plants that burn fossil fuels and those activities that release heavy pollutants to the atmosphere and the ground, such as irresponsible mining. The recent spill on the Animas River from a Colorado mine — and its impact in Navajo Nation farming lands downstream — is a reminder of this. It is ironic that the spill was due to an investigation by the Environmental Protection Agency.

China has been choking on coal burning fumes to fuel its industrial growth. Meanwhile, the Obama administration is trying to cut domestic production of greenhouse gas emissions by 28 percent — to 2005 levels — by 2025. China's authorities are aware of this, and are closing all of Beijing's coal burning plants next year, substituting them with gas-fire alternatives capable of producing 2.6 times more electricity. The trend there is clear, as apart from gas, China is encouraging broader use of solar, wind and hydroelectric power. Germany is doing the same, betting on alternative sources of energy as having the potential for spurring economic and technological growth.

The Obama administration is about to propose the first-ever control on methane emissions, another powerful greenhouse gas. While methane contributes only nine percent of all greenhouse gases, it's 20 times more potent than carbon dioxide: Small improvements can have big impacts. Even if these measures are sure to face opposition in Congress and from gas-extracting companies, they come at the right time, preparing the ground for the Paris conference on global warming in December.

Hopes are high that the big players will forge a meaningful accord, beginning a new phase in pollution control where our sense of pride and civism extends from our cities and countries to the world as a whole. After all, the air we breathe is different from the ground we walk. It moves and gets cycled around, being shared by all.

Marcelo Gleiser is a theoretical physicist and cosmologist — and professor of natural philosophy, physics and astronomy at Dartmouth College. He is the co-founder of 13.7, a prolific author of papers and essays, and active promoter of science to the general public. His latest book is The Island of Knowledge: The Limits of Science and the Search for Meaning. You can keep up with Marcelo on Facebook and Twitter: @mgleiser.

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