Earth Day 2015

This is the 45th anniversary of Earth Day. As I have been saying for the past few days, every day needs to be earth day, but it is still helpful to celebrate it annually. My own involvement in Earth Day goes back to the very first one in 1970. As a PhD student in Demography at the University of California, Berkeley, I was invited to address what turned out to be a very large outdoor gathering on the campus of California State University, Fresno. Fresno County is the most productive agricultural county in the United States, although its current biggest crop, almonds, takes a huge--almost certainly unsustainable--amount of water. At the time, though, few of us were thinking about water scarcity. The truth was that growing food was an unabashedly good thing, since we knew there were going to be lots of new mouths to be fed in the future. My talk was "Who Lit the Fuse on the Population Bomb?" and of course the answer was "look in the mirror":

Europeans and Americans are responsible for the world's population problems. It all began 200 years ago in the early days of European and American economic development...[you know the rest of the story if you've read my book]. 

I used the opportunity to push for change, keeping in mind that in 1970 the average woman in the United States was giving birth to 2.5 babies, virtually all of whom would survive to adulthood. Fertility was on the way down, to be sure, but it wasn't clear in 1970 whether or not that was a long-term trend.

We should definitely advocate for the immediate removal of all discriminatory barriers in education and in the professions [remember that this was the first year that women had been admitted as undergraduates at Princeton]. If you can get a woman out of the house and reward her with financial gain and social and economic prestige, then the social and economic costs of having additional children are going to increase for that woman and she is far more likely than ever before to prefer a small family.

You will recognize the importance of that theme in almost everything that I have written since then. Keep in mind that between then and now we have added 115 million people to the U.S. population, although the birth rate has dropped to just below replacement level. At the same time the world's population has almost exactly doubled--from 3.7 billion in 1970 to 7.3 billion in 2015. Fortunately, the global birth rate is also on the way down from about 4.6 children then to 2.5 children now. We're not out of the woods yet, though. There will be many more Earth Days before we can relax.