Earth’s Carrying Capacity. That’s a myth

Theology at the end of this blog. First, some environmental talk. I have an occupational background in environmental biology (not to mention a Master’s degree in International Development), so I understand the idea of carrying capacity. And I don’t believe in the idea that Earth has a “carrying capacity” of humans. Drawn over from environmental studies of animals in an ecosystem, the reason this is a non-starter for me in regards to human population, is that history has shown, time and time again, that people are capable of creatively adapting and developing ways to live in an ecosystem far beyond what its “previous” carrying capacity was thought to be prior to the innovation.

Estimates of the carrying capacity of the Earth (for human population) since van Leeuwenhoek in 1679, have been laughably incorrect over and over again, not to mention ranging from 1 billion to 1000 billion! The low end estimates were based on the agricultural technology of the day (tillable acres and output divided by human consumption per capita) and those estimates of carrying capacity have been repeatedly increased due to the increase in agricultural output per acre enabled by new advances in farming practices. I’m typing this on Point Loma, a very densely populated part of San Diego. The carrying capacity of this area is a million fold what it would have been for the Diegan Indios 500 years ago, but then we aren’t hunter-gatherers. I’ve lived on one of the most densely populated pieces of land in the world: Java, Indonesia. Rice terracing and fish farming have increased the food-producing capabilities of that land far beyond its natural contours. As a 2012 UN study put it, “technological advances in efficiency can be a divisor of per capita impact.” 1 When the interdependent variables in dynamic systems modeling today are applied to carrying capacity, there are so many estimates regarding future variables, the range of estimates becomes so huge as to be meaningless. A 1995 article in Science called for “extreme skepticism” regarding carrying capacity estimates for the reasons I’ve just cited. 2

A meme I saw said “God makes a world for humans – 70 % saltwater ocean.” It was witty on the surface, but it really doesn’t make the point it attempts. Humans figure out how to live in ecosystems as we go. Our ancestors walking out of Africa could not have survived near the Arctic Circle with the savannah lifestyle they knew – but the Inuit and Eskimo have learned how to thrive there for thousands of years – with only Neolithic technology! 70% of our world is indeed oceanic – but we have only scratched the surface on learning how to live there. We can learn to live in oceanic environments just as surely as we did in Arctic ones. Aquatic farming is just in its earliest stages. Not only is there plenty more for us to learn about farming Earth’s various biomes, but we haven’t even hardly started with urban farming and stackable skyscraper farms. Figures for carrying capacity are always and utterly tied to current technology and practices. Any talk of carrying capacity should start by saying “If we never, ever do a single thing different than we do today…” And that’s just silly.

But there’s a strong theological reason to question the idea of carrying capacity. For those Christians who believe we are past the carrying capacity of the Earth, we need to ask “Which of the people currently alive would the Creator God prefer had never been born?” It is theologically repugnant, from a Christian point of view, to imagine there are any. We don’t need less people created in the imago dei. We simply need what every group of people have needed (and worked out) since the digging stick was invented and there were more babies born in the tribe: new ways to find, (or in our case) increase, harvestable output.

And by the way, there is no shortage of food in the world per capita. There are local scarcities we haven’t transported to effectively. It’s not a quantity issue, it’s a transportation issue and a governance issue. Next time let’s talk about carrying capacity and pollutants in a closed system.

1 http://na.unep.net/geas/archive/pdfs/geas_jun_12_carrying_capacity.pdf

2  ttp://www.montana.edu/screel/Webpages/conservation%20biology/cohen.pdf

Advertisements

Environmental Policy

With our new life on the shore of Lake Erie, I seem to have a hard time getting back to the blog. But, to continue from last time, here’s how it went down:

It had been a beautiful wedding in a mansion that had once been owned by Andrew Carnegie, overlooking one of his favorite trout streams. I was sitting at the reception across the table from a Pennsylvania Senator’s chief aide. Our conversation was wild and wide-ranging, and since we liked many of the same things, very enjoyable. Somewhere in there, I laughingly said, concerning his Republican boss, “How can a political party jam-packed with hunters, fishermen and other passionate outdoorsmen, constantly find themselves on the wrong end of every environmental issue, every time you turn around?” Suddenly my companion turned dead serious. “They get it,” he said. “But it’s the money. They accept so much money from Big Oil and Big Business and Big Energy companies, they end up voting against the environment all the time. And it is killing us with young people.” I don’t remember the exact words of what all else he said, but he clearly expressed his frustration at knowing that money was buying votes that were clearly against the common good.

Now, we say this kind of thing all the time, “follow the money,” but here was the highest aide of a prominent Senator telling me that it was exactly the case. I don’t know really what to do to solve that problem, except to say that it may very well be that the answers to many of our pressing problems are not going to come from Washington D.C. It’s dis-heartening, because, as great organizations like Bread for the World have found, it’s a powerful venue.

But I wonder if the way things get turned around are more through cultural grass-roots movements in regular neighborhoods and regular high schools and regular towns, so that there is a growing crescendo in the culture that some things are simply not acceptable, and that vibe or perspective percolates upwards to the extent that finally enough representatives believe something to be generally true in the culture that their voting simply reflects the new milieu. I don’t know, but it worked for the environmental movement, who were considered whack-jobs in the 1960s and yet now, in 2016, every single one of their major talking points is considered normative in our culture; (Of course you recycle, of course you conserve energy, of course you don’t litter, etc etc). The fact that very powerful money now works against that enlightened awareness, remains a conundrum. In the meantime, maybe teach a kid to garden and fish.

Henry Beston, writing from his farm in Maine, said this in 1948:

It often strikes me that in our modern Babylons you never see anything begin. Everything comes to you, even thought, at a certain stage in its development, like an iceberg lettuce. Now life is more a matter of beginnings than of endings, and without some sense of the beginning of things, there is no proper perspective on the whole mystery of living. This is only one detail, but it will serve as one of the marks of the whole incomplete urban perspective in which we live. For the city governs us now as never before; it tells us what to love and what to hate, what to believe and what not to believe, and even what to make of human nature.” (Northern Farm, by Henry Beston; Ballantine: 1948).