Richer Means Greener

As a country gets richer, does that lead to more pollution or less? Back in the early days of the modern environmental movement there was an equation that many of us learned. At the first Earth Day was learned that I=PAT. The environmental impact (I) was equal to the population (P) multiplied by affluence (A) multiplied by technology (T). In other words, as a country grew in population and affluence and technology, the worse the pollution and environmental impact. So the best way to protect the planet would be to have fewer people, less wealth, and simpler technology.

It was an interesting equation, but it turned out to be wrong as countries got richer. John Tierney points this out in a recent column in The New York Times. He points out that the “IPAT theory may have made intuitive sense, but it didn’t jibe with the data that has been analyzed since that first Earth Day.” Researchers instead found that the graphs of environmental impact with a simple upward-sloping line were wrong. Instead, it turns out that the line flattens out and then slopes downward. Think of an upside-down U on the graph. This is called a Kuznets curve.

Generally the trend is as countries get richer they have more incentive and more financial means to clean up pollution. Of course there are exceptions (especially with countries with inept governments and poor system of property rights). But the general rule is that as incomes go up, people focus on pollution.

Tierney says: “As their wealth grows, people consume more energy, but they move to more efficient and cleaner sources — from wood to coal and oil, and then to natural gas and nuclear power, progressively emitting less carbon per unit of energy. This global decarbonization trend has been proceeding at a remarkably steady rate since 1850.”

I think this suggests a positive environmental future for developing countries. They may be ascending the Kuznets curve right now, but this could change once they are heading down the slope of the curve and address environmental concerns. I’m Kerby Anderson, and that’s my point of view.