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If only it were plausible.

Nordhaus’s argument hinges on dismissing the longstanding biological concept of “carrying capacity” — the number of organisms an environment can support without becoming degraded. “Applied to ecology, the concept [of carrying capacity] is problematic,” Nordhaus writes, arguing in a nutshell that the planet’s ability to support human civilization can be, one presumes, infinitely tweaked through a combination of social and physical engineering.

Few actual ecologists, however, would agree. Indeed, the concept of carrying capacity is useful in instance after instance — including modeling the population dynamics of nonhuman species, and in gauging the health of virtually any ecosystem, be it ocean, river, prairie, desert, or forest. While exact population numbers are sometimes difficult to predict on the basis of the carrying capacity concept, it is nevertheless clear that, wherever habitat is degraded, creatures suffer and their numbers decline.The controversy deepens in applying the carrying capacity concept to humans. Nordhaus seems to think we are exceptions to the rules. …..

The core of Nordhaus’ case is that we are now living in a magical society that is immune to the ecological law of gravity. Yes, it is beyond dispute that the modern industrial world has been able to temporarily expand Earth’s carrying capacity for our species. As Nordhaus points out, population has grown dramatically (from less than a billion in 1800 to 7.6 billion today), and so has per capita consumption. No previous society was able to support so many people at such a high level of amenity. If we’ve managed to stretch carrying capacity this much already, why can’t we do so ad infinitum?

To answer the question, it’s first important to understand the basis of our success so far. Science and technology usually glean most of the credit, and they deserve their share. But sheer energy — the bulk of it from fossil fuels — has been at least as important a factor.

With lots of cheap energy, we were able to extract raw materials faster and in greater quantities, transport them further, and transform them through industrial processes into a breathtaking array of goods — including fertilizers, pesticides, and antibiotics, all of which tended to reduce human death rates.

But there was still another essential factor in our success: nature itself. Using science, technology, and cheap energy, we expanded farmlands, chain-sawed forests, exploited fisheries, mined minerals, pumped oil, and flattened mountains for their buried coal. And we did these things in a way that was not remotely sustainable. By harvesting renewable resources faster than they could regrow, by using non-renewable resources that could not be recycled, and by choking environments with industrial wastes, we were borrowing from future generations and from other species.

……… a cottage industry of environmental scientists, led by Johan Rockström of the Stockholm Resilience Center and Will Steffen of the Australian National University, has identified nine planetary boundaries that we transgress at our peril: climate change, ocean acidification, biosphere integrity, biochemical flows, land-system change, freshwater use, stratospheric ozone depletion, atmospheric aerosol loading, and the introduction of novel entities into environments.

We are currently exceeding the “safe” marks for four of these boundaries:

Another way of keeping track is the ecological footprint, which measures human demand on nature in terms of the quantity of land and water it takes to support an economy sustainably. The Global Footprint Networkcalculates that humanity is currently exceeding Earth’s sustainable productivity by 60 percent. We do this, again, by drawing down resources that future generations and other species would otherwise use. So, as a result of our actions, Earth’s long-term carrying capacity for humans is actually declining …

DEVISE YOUR own scorecard. What warning signs would you expect to see if we humans were pressing at the limits of global carrying capacity? Resource depletion? Check. Pollution? Check. Dying oceans? Check. Human populations subjected to increasing stress? Double check.

Here’s one more that we probably should be paying more attention to: Wild terrestrial mammals now represent just 4.2 percent of terrestrial mammalian biomass, the balance — 95.8 percent — being livestock and humans. Maybe we could make some inroads on that remaining 4.2 percent, but it’s pretty clear from this single statistic that we humans have already commandeered most of the biosphere…..https://undark.org/article/ted-nordhaus-carrying-capacity-ecology/