Slashdot Mirror
Modeling the Economy As a Physics Problem
University of Utah physicist Tim Garrett has published a study that approaches the economy and its relation to global warming as a physics problem — and comes to some controversial conclusions: that rising carbon dioxide emissions cannot be stabilized unless the world's economy collapses or society builds the equivalent of one new nuclear power plant each day. The study was panned by economists and was rejected by several journals before its acceptance in the journal Climatic Change. "[Garrett discovered that] Throughout history, a simple physical constant... links global energy use to the world's accumulated economic productivity, adjusted for inflation. So it isn't necessary to consider population growth and standard of living in predicting society's future energy consumption and resulting carbon dioxide emissions. ... 'I'm not an economist, and I am approaching the economy as a physics problem,' Garrett says. 'I end up with a global economic growth model different than they have.' Garrett treats civilization like a 'heat engine' that 'consumes energy and does "work" in the form of economic production, which then spurs it to consume more energy,' he says. That constant is 9.7 (plus or minus 0.3) milliwatts per inflation-adjusted 1990 dollar. So if you look at economic and energy production at any specific time in history, 'each inflation-adjusted 1990 dollar would be supported by 9.7 milliwatts of primary energy consumption,' Garrett says. ... Perhaps the most provocative implication of Garrett's theory is that conserving energy doesn't reduce energy use, but spurs economic growth and more energy use."
We have to stop somewhere. At six billion or six trillion. It has to happen. The Heinlein fan in me says this will happen with war and starvation. Its not that hard to imagine, it happens all the time.
Or we can learn to regulate our population, as the Chinese are trying to do. Even in the last 30 years there has been a recognition that high standards of living reduce fertility. But have China and India gone too far for this to work? I am sure the US nearly did, because you have to wear high birth rates and high energy consumption at the same time for a while (the 1950s) for it to work. The same peak would put the energy consumption of 10 billion USA or AU people in China alone.
Don't ask me for help. I'll be starting a farm on Ganymede.
http://michaelsmith.id.au
So, is the economy or global warming treated as a perfect sphere?
This fits with an observation by insurance companies (or at least mine, USAA) that building safer cars results in people continuing to drive them to their preferred safety margin. We still end up with about as many crashes (but injuries are less).
While this is probably largely true, human demands do seem to expand to fill available resources, our demands aren't infinite.
The marginal value of your first dollar, or 10 dollars(depending on local cost of living), is enormous. You get to eat. The marginal value of your 1,000,001th dollar is a great deal smaller.
There isn't a fixed "ceiling" above which people demand no more energy; but there are a number of "floors" below which things get really ugly, really fast(like, "Rwandan Genocide" bad, not just "I want a cooler yacht" bad). If you can increase efficiency enough, it should be possible to reduce the amount of damage that needs to be done in order to head off genuinely bad outcomes.
There is also a second factor to consider: When people are desperate(or ignorant, or stupid), they will be willing to consume their capital to survive. Destroying fish stocks by catching juveniles, farming harder and harder until the topsoil erodes, polluting water supplies, eating the seed corn, deforestation to make charcoal(on the subject of deforestation, compare the Dominican Republic with Haiti. Same island, same location, one country has its forests, one doesn't. The Dominican Republic is merely poor. Haiti is deeply fucked.), and so forth. Even in strict economic terms(i.e. setting the intrinsic worth of "the environment", beyond its practical utility, at 0) this is a stupid plan. If the alternative is starving, though, people will do it anyway. If efficiency increases, fewer people will be desperate enough to eat their capital instead of their income.
There's another implication of that theory, and it's one that conservatives have been arguing for some time now: the end result of the current drive to cut back on carbon dioxide emissions is the destruction of the worlkd economy.
Disinfect the GNU General Public Virus!
Perhaps the most provocative implication of Garrett's theory is that conserving energy doesn't reduce energy use, but spurs economic growth and more energy use.
While I can't speak to the validity of the underlying theory as such, a conclusion like this doesn't really come as a shock. The 20th century saw an steady stream of "labor-saving" inventions that are now part of our daily lives, but we don't have more leisure time than our ancestors -- in many cases, we actually have less -- because all of that liberated time was promptly consumed by new forms of work.
Sooner or later, we're going to have to come to terms with our now obsolete species-wide obsession with material acquisition. It made sense before we developed tools and civilization: grab all you can while it's abundant because scarcity is the norm. Now that we have all we actually need and then some, we're just killing ourselves with the byproducts of our superfluous production.
Proud member of the Weirdo-American community.
Which is why Eastern Europe and the former Soviet Union are environmental Garden of Edens.
"The average reporter we talk to is 27 years old......They literally know nothing." - Ben Rhodes
This sounds like Jevons Paradox.
http://en.wikipedia.org/wiki/Jevons_paradox
When we conserve energy, we can and do use the saved energy for other activities. "conservation" is not really conservation if we promptly use the saved energy for another activity.
Consider the food supply. The population has now reached a size at which the current amount of food is not sufficient for everyone to eat well. So, scientists at ADM and other companies are trying to invent new ways to increase food production. Suppose that the scientists succeed and that we increase food production by 20%. The population, enjoying this additional food, now grows by an additonal 20%: we return to the original problem.
In the long run, the 4 horsemen will eventually impose their own solution on humankind. Many people will die in the process.
Inevitably, some Slashdotter will claim that yet-to-be discovered technology will always provide a fix for the problem. Believing that yet-to-be discovered technology will be discovered (and will be the salvation) is exactly equivalent to believing the numerous claims of religion. Often, the same Slashdotter who is atheist does not hestitate to believe in yet-to-be discovered technology. A hypocrite, a fool, or both?
Economists routinely use highly complicated mathematical models on stuff like this, and are just as routinely criticised for it because their simplifying assumptions aren't close enough to reality. Then along comes this bloke and uses a model that's not even based on human behaviour: the economy as a heat engine. No wonder he's been panned. Criticise economic models all you like, but at least the modern ones* have a foundation in human behaviour.
I can see why this gets a run here – scientists are cool nerds; economists are not – but in the end it's a guy doing research outside of his field. Sometimes you get tremendous insights, but most of the time (as in this case) you don't.
* I'm not talking about the physiocrats here, okay?
Disclaimer: I am an economist.
Antiquis temporibus, nati tibi similes in rupibus ventosissimis exponebantur ad necem.
"or society builds the equivalent of one new nuclear power plant each day."
I don't have a problem with this. Let's get building.
Eventually we'll turn towards the sun, and nuclear will only be our failsafe, but I have no problem with it filling in the gaps.
It's a side issue, but this is complete hogwash. Every organism will increase as much as possible - they don't "instinctively" come to equilibrium, equilibrium is forced on them by competition. In the event that an organism becomes so well adapted that it dominates its competition, its numbers will increase until it dies off as a result of increasing beyond the carrying capacity of the environment. A good example: snow geese. For many years, snow goose populations were very low because their natural habitats were limited. But then, beginning about in the 70's, two things happened: 1) snowy owl populations increased in the far north, which had the effect of increasing snow goose nesting success by driving away snow goose predators, and 2) snow geese learned to exploit a new (to them) resource: agricultural waste. As a result of those two factors, the snow goose population exploded. Unfortunately, however, it didn't "come to equilibrium" with its environment - snow geese are now so overpopulated that they're destroying both their spring breeding grounds and their wintering grounds. Unless the population can be gotten under control through hunting (which so far has had pretty limited success), a population crash is inevitable
There are other examples of the same phenomenon in other species, but what's relevant here is that humans are just an extreme example. We are so tremendously adaptable that we've been able to colonize nearly every environment on the surface of the earth, and have so outstripped every other creature that our population has grown too much for the earth to support it. That's a real problem, and I don't mean to pooh-pooh it. But I do get annoyed when I hear more examples of the meme that "animals (and primitive humans) lived in harmony with the earth, but evil (modern) man has forgotten how to do this". It's just not true - all species expand to fill all available space in whatever niche they occupy.