May 23, 2013--Malthus

On our way north from Florida Rona suggested we drive up the Delmarva Peninsula. Along Chesapeake Bay. The last time we did was more than 25 years ago and it was interesting and beautiful.

"I remember that," I said, "Rural fishing villages and ancient farmlands. It was enchanted. A place that time seemed to forget."

But when only a few miles north of the 20-mile bridge from Norfolk, we encountered a seamless string of shopping plazas where there were more Pizza Huts and Dunkin' Donuts than farms and rolling pastures.

"What happened?" I sighed, "Are all these condos second-homes for folks who work acrooss the Bay in Washington?"

"Probably," Rona said, upset that she had recommend this now spoiled route. "I know Dick Cheney and Donald Rumsfeld have homes here."

Later, when checking with friends who live and work in DC, they confirmed that many of the ticky-tacky houses were indeed vacation or retirement homes, but most were for the increased population of the Peninsula.

This got me thinking more generally about the growth in population, something surprisingly not all that much discussed when we talk about global issues, very much including climate change.

Some quick research revealed that the population in the U.S. grew from 130 million the year I was born to 316 million now, an increase of 240 percent. And the population of the world during that same time grew from 2.3 billion to about 7.0 billion, a staggering increase of 329 percent.

This does not bode well for the planet. or humans. If the rate of growth continues for another 50-60 years we will see another doubling in the size of the population. That is unless a series of health, war, or environmental catastrophes intercede.

From recent reports that the amount of heat-trapping carbon dioxide in the air now exceeds 400 parts per million--the first time this has been true in nearly 3.0 million years (well before humans evolved) a generally-agreed dangerous level--it may be that we are approaching a point of no return. There may be no turning back from the combination of high population growth and, due to economic development, the concomitant use of carbon and fossil fuel. Unless we change our behavior, together they will continue to shape a doomsday scenario.

The sustainability of exponential population growth was very much a part of late 18th century discourse. At the same time that Enlightenment thinkers such as William Godwin and Jean-Jacques Rousseau were proclaiming that human progress was limitless, there were others arguing that this was a false notion, that because resources were not infinite, human progress would inevitably be constrained as population grew to the point where it outstripped our very finite resources.

Best known was the Reverend Robert Malthus who proclaimed the Iron Law of Population, which could be summarized from something he wrote in his 1798 Essay on the Principle of Population--

"The increase in population is necessarily limited by the means of subsistence."

Malthus' Malthusian jeremiad was quickly pushed aside as the Industrial Revolution produced such a wealth of goods and services that it did look as if progress was boundless.

But now we know the Iron Law is more true than false; and, as part of the mix, as we struggle with climate and sustainability issues, should be population concerns. It is hard to imagine anyone making a convincing case that the Earth is capable of supporting a global population of 10 to 15 billion. But during the remainder of this century that is where we are in fact headed. If this were to occur, the consequences will not be pretty.