Linus Blomqvist, Ted Nordhaus, and Michael Shellenberger write,
Slowing population growth, demand saturation in developed countries, and improved technological efficiencies have all contributed to what is known as decoupling. Relative decoupling refers to impacts growing at a slower rate than population or consumption. Absolute decoupling means impacts are declining in absolute terms. The per-capita farmland requirement (cropland and pasture) has declined by half in the last half-century. In absolute terms, cropland has expanded 13% and pasture 9% in that time period, but the sum of the two has remained stable since the mid-1990s. Global consumption of wood has plateaued, contributing to a slight decline in the area of production forest since 1990. While overharvesting of wild animals for meat has increased in the tropics, most developed countries have decoupled from this form of impact. The world has almost entirely decoupled from whaling. Total water consumption increased by 170% between 1950 and 1995, but per-capita water consumption peaked around 1980 and declined thereafter. The least decoupled environmental impact is greenhouse gas emissions from energy: global per-capita emissions increased by nearly 40% between 1965 and 2013.
Pointer from Justin Fox, who adds insightful commentary. Via Mark Thoma.
There seems to be a lot of similar environmental commentary out this year. Ron Bailey’s new book, Jesse Ausubel’s paper, and now this (which credits Ausubel).
I recommend the entire paper. I think it would be accessible to students in freshman economics courses, and I really believe that if freshman economics ignores this topic, that means that the primitivists will be unopposed on college campuses.
The moral of the story is not ‘dematerialization’ at all, but material substitution. Aside from government prohibitions, the reason we don’t need to hunt whales anymore except to provide novelty consumption experiences is because no one needs to burn whale oil.
And consider:
Ok, but there are material substitutes for wood too, often energy-intensive ones, (where China has a comparative advantage from plentiful, cheap, and dirty coal) so less impact in one place could mean more in another. It’s like trying to push a snake through a pipe – you push in one side, but then it pops out the other. There are plastics and resins for furniture, fiber-materials for boats, metal and cement and composite polymers for construction, silicon chips and electricity for paper, etc.
Indeed, just on my own block in the last few years, I’ve watched projects that swapped out wood decks for composites, wood siding for vinyl (or something), cedar shake roofing for some kind of synthetic material, etc.
That probably sounds like a nitpick, but how do we make sure these anecdotal examples don’t aggregate into what turns out to be a giant shell game because of these forms of substitution? “A lot of things are ‘decoupling’, but then there’s this one thing over there that didn’t decouple, but that’s an exception.” Well, no, not if that ‘one thing over there’ is the reason everything is decoupling.
So that’s neither less material nor less impact, it’s a fallacy of getting an overall impression by counting by number of categories instead of applying some kind of sensible weighting to those categories.
Also, I’m not sure I buy the “decline in water per capita consumption” story as ‘decoupling’ at all, at least in terms of being caused solely by market forces and shifting consumer preferences. Dryer places continue to use all they can afford to get.
The annual water supply is pretty inelastic (go ask California, or Yemen), and water is very expensive to move, so as population grows in any area facing at the scarcity edge and facing supply constraints, it makes sense that the price would rise (or there would be rationing of some kind) and people would have to use less per capita, while still responding to the incentives of price signals and investing a lot more energy (substitution again!) into pumping a slightly greater amount up and around.
It’s true, but those substitutes seem much lighter on resources than growing a tree or growing a whale.
Water supply *could* be both elastic and mobile, but efforts to build proper markets around water run into a lot of political opposition, especially in California.
In terms of digital and demographic dematerialization, should this be included in Macroeconomics as well? If people are buying less stuff, then you would expect less investment is necessary. Doesn’t that create the world’s largest ‘liquidity trap’ as there is more savings than investment opportunities. (Considering rates are near zero it implies this is correct.)