I’ll admit it. I’m an Earth Day adolescent. I was there at the National Mall in Washington, D.C. on the first Earth Day, April 22, 1970, among the bell bottoms and long hair. The atmosphere was electric. We were united by a cause and a rallying cry. How simple it seemed at the time. Polluters were bad, greedy, and out to ruin the world. Environmentalists were always in the right. The issues seemed so comfortably black and white.
The environmental issues of that time were not easy to solve—and some still remain unsolved—but they were easy to identify. Everyone could smell the smog in the cities and see dead fish floating belly-up in toxic rivers. Everyone could understand that lead in gas and chipping paint poisons children. No one could deny the TV images of Ohio’s Cuyahoga River aflame from the brew of industrial chemicals. Four decades later, air and water pollution that people can see, smell, and feel in their own neighborhoods is now vastly reduced—at least in this country. Fish are back in the Cuyahoga River, and New York’s air is far cleaner than it was a few decades ago.
That was the easy part. It’s more complicated today.
What’s happened since the first Earth Day? First there was acid rain, where air filled with sulfur from burning coal traveled downwind across state and national boundaries. The low-pH rain corroded buildings, killed trees, and turned lakes into acid baths. Laws, treaties, and technology to scrub the sulfur from coal have made great strides in solving that problem. Then there was stratospheric ozone, caused by a single chemical that rises in the atmosphere and destroys the ozone that shields us from ultra-violet rays. The atmosphere is a great mixer, so one country’s emissions becomes another country’s depleted ozone. Here was the first truly international environmental issue. This one too is largely solved, thanks to the success of international agreements to ban the culprit. The next big issue that came along was climate change, another truly global issue. But climate change is messy scientifically, politically, and economically, whereas stratospheric ozone was straightforward science with economically and politically feasible solutions. No clear solutions to climate change are on the horizon. And then there is the loss of species as forests turn to farms and displaced plants and animals have nowhere to go. That’s another global issue, but it’s hardly on the agenda. The shift since the first Earth Day from local environmental issues to the global issues of today make solutions even more complex as the agendas of different countries collide.
If the local pollution issues at the time of the first Earth Day were black and white, today’s issues are all shades of gray. The world cannot be cleaved cleanly into good guys and bad guys. Is the energy company that spews greenhouse gases while providing power for a poor child to do his homework at night in India or Africa a good guy or a bad guy? What about the farmer who cuts down trees to grow food to feed his family? Or the industry that dumps pollutants into the river but provides jobs to put food on the table? Who bears the burden for climate change, the industrialized countries that created the problem in the past or the emerging economies that—if current trends prevail—will bear the brunt of the problem in the future?
Black-and-white environmentalism has given way to the mantra of sustainable development, a more balanced perspective that sees people not as enemies of the environment but part of it. Food to feed the world’s growing appetite is no less crucial, or is perhaps more crucial, than saving species or preserving a wetland. One out of six people in the world can’t afford a decent life. Do opportunities to earn a living wage trump environmental damage from a factory? Trade-offs abound. Who decides?
Today’s environmental—or rather sustainable development—issues are a lot harder than the black-and-white issues of the first Earth Day. Climate change, biodiversity, and producing food to feed the world are more intertwined, complex, global, and nuanced than cleaning up local pollution. No one knows what other issues might arise. I wish I could say that solutions are around the corner or that you could listen to a lecture or read a book and get the answers in a neat, ready package. On this 41st Earth Day, I can only say that solving today’s environmental issues is a lot harder than it was for your bell bottom-clad predecessors.
The new Columbia major in sustainable development aims to convey the complexity of environmental issues and the inter-relations with poverty alleviation, development, energy, and a host of other factors we face together. The response from the students has been fantastic. All of us in the program look forward to working with you on unraveling options for society’s path ahead.
The author is the co-director of the undergraduate program in sustainable development and the Denning Family Professor of Sustainable Development in the department of ecology, evolution and environmental biology.


