Fifty years ago this week, people turned out in vast numbers to celebrate the natural environment and call for its protection. Earth Day was a response to increasing awareness of the impact of the 20th century economy on our air, water, land and animal life. Smog and soot fouled the air, rivers ran with so much industrial and human waste that some were literally catching fire, oil slicks had closed popular beaches.
Fast forward 50 years. This Earth Day will not see large, exuberant gatherings, but the need for people to step up and demand change is greater than ever. We still need to defend clean air and water, public lands and threatened species, but we also have to confront less visible and more systemic challenges: the altered chemistry of our atmosphere and oceans, vast shifts in the way we use land and generate waste, local and global inequities that visit environmental hardships most often upon communities of color and areas of high poverty.