Malthus

Actually, our economic growth has been fairly ecologically sustainable lately!

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JDN 2457538

Environmentalists have a reputation for being pessimists, and it is not entirely undeserved. While as Paul Samuelson said, all Street indexes have predicted nine out of the last five recessions, environmentalists have predicted more like twenty out of the last zero ecological collapses.

Some fairly serious scientists have endorsed predictions of imminent collapse that haven’t panned out, and many continue to do so. This Guardian article should be hilarious to statisticians, as it literally takes trends that are going one direction, maps them onto a theory that arbitrarily decides they’ll suddenly reverse, and then says “the theory fits the data”. This should be taught in statistics courses as a lesson in how not to fit models. More data distortion occurs in this Scientific American article, which contains the phrase “food per capita is decreasing”; well, that’s true if you just look at the last couple of years, but according to FAOSTAT, food production per capita in 2012 (the most recent data in FAOSTAT) was higher than literally every other year on record except 2011. So if you allow for even the slightest amount of random fluctuation, it’s very clear that food per capita is increasing, not decreasing.

global_food.png

So many people predicting imminent collapse of human civilization. And yet, for some reason, all the people predicting this go about their lives as if it weren’t happening! Why, it’s almost as if they don’t really believe it, and just say it to get attention. Nobody gets on the news by saying “Civilization is doing fine; things are mostly getting better.”

There’s a long history of these sorts of gloom and doom predictions; perhaps the paradigm example is Thomas Malthus in 1779 predicting the imminent destruction of civilization by inevitable famine—just in time for global infant mortality rates to start plummeting and economic output to surge beyond anyone’s wildest dreams.

Still, when I sat down to study this it was remarkable to me just how good the outlook is for future sustainability. The Index of Sustainable Economic Welfare was created essentially in an attempt to show how our economic growth is largely an illusion driven by our rapacious natural resource consumption, but it has since been discontinued, perhaps because it didn’t show that. Using the US as an example, I reconstructed the index as best I could from World Bank data, and here’s what came out for the period since 1990:

ISEW

The top line is US GDP as normally measured. The bottom line is the ISEW. The gap between those lines expands on a linear scale, but not on a logarithmic scale; that is to say, GDP and ISEW grow at almost exactly the same rate, so ISEW is always a constant (and large) proportion of GDP. By construction it is necessarily smaller (it basically takes GDP and subtracts out from it), but the fact that it is growing at the same rate shows that our economic growth is not being driven by depletion of natural resources or the military-industrial complex; it’s being driven by real improvements in education and technology.

The Human Development Index has grown in almost every country (albeit at quite different rates) since 1990. Global poverty is the lowest it has ever been. We are living in a golden age of prosperity. This is such a golden age for our civilization, our happiness rating maxed out and now we’re getting +20% production and extra gold from every source. (Sorry, gamer in-joke.)

Now, it is said that pride cometh before a fall; so perhaps our current mind-boggling improvements in human welfare have only been purchased on borrowed time as we further drain our natural resources.

There is some cause for alarm: We’re literally running out of fish, and groundwater tables are falling rapidly. Due to poor land use deserts are expanding. Huge quantities of garbage now float in our oceans. And of course, climate change is poised to kill millions of people. Arctic ice will melt every summer starting in the next few years.

And yet, global carbon emissions have not been increasing the last few years, despite strong global economic growth. We need to be reducing emissions, not just keeping them flat (in a previous post I talked about some policies to do that); but even keeping them flat while still raising standard of living is something a lot of environmentalists kept telling us we couldn’t possibly do. Despite constant talk of “overpopulation” and a “population bomb”, population growth rates are declining and world population is projected to level off around 9 billion. Total solar power production in the US expanded by a factor of 40 in just the last 10 years.

Of course, I don’t deny that there are serious environmental problems, and we need to make policies to combat them; but we are doing that. Humanity is not mindlessly plunging headlong into an abyss; we are taking steps to improve our future.

And in fact I think environmentalists deserve a lot of credit for that! Raising awareness of environmental problems has made most Americans recognize that climate change is a serious problem. Further pressure might make them realize it should be one of our top priorities (presently most Americans do not).

And who knows, maybe the extremist doomsayers are necessary to set the Overton Window for the rest of us. I think we of the center-left (toward which reality has a well-known bias) often underestimate how much we rely upon the radical left to pull the discussion away from the radical right and make us seem more reasonable by comparison. It could well be that “climate change will kill tens of millions of people unless we act now to institute a carbon tax and build hundreds of nuclear power plants” is easier to swallow after hearing “climate change will destroy humanity unless we act now to transform global capitalism to agrarian anarcho-socialism.” Ultimately I wish people could be persuaded simply by the overwhelming scientific evidence in favor of the carbon tax/nuclear power argument, but alas, humans are simply not rational enough for that; and you must go to policy with the public you have. So maybe irrational levels of pessimism are a worthwhile corrective to the irrational levels of optimism coming from the other side, like the execrable sophistry of “in praise of fossil fuels” (yes, we know our economy was built on coal and oil—that’s the problem. We’re “rolling drunk on petroleum”; when we’re trying to quit drinking, reminding us how much we enjoy drinking is not helpful.).

But I worry that this sort of irrational pessimism carries its own risks. First there is the risk of simply giving up, succumbing to learned helplessness and deciding there’s nothing we can possibly do to save ourselves. Second is the risk that we will do something needlessly drastic (like the a radical socialist revolution) that impoverishes or even kills millions of people for no reason. The extreme fear that we are on the verge of ecological collapse could lead people to take a “by any means necessary” stance and end up with a cure worse than the disease. So far the word “ecoterrorism” has mainly been applied to what was really ecovandalism; but if we were in fact on the verge of total civilizational collapse, I can understand why someone would think quite literal terrorism was justified (actually the main reason I don’t is that I just don’t see how it could actually help). Just about anything is worth it to save humanity from destruction.

What are the limits to growth?

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JDN 2456941 PDT 12:25.

Paul Krugman recently wrote a column about the “limits to growth” community, and as usual, it’s good stuff; his example of how steamships substituted more ships for less fuel is quite compelling. But there’s a much stronger argument to made against “limits to growth”, and I thought I’d make it here.

The basic idea, most famously propounded by Jay Forrester but still with many proponents today (and actually owing quite a bit to Thomas Malthus), is this: There’s only so much stuff in the world. If we keep adding more people and trying to give people higher standards of living, we’re going to exhaust all the stuff, and then we’ll be in big trouble.

This argument seems intuitively reasonable, but turns out to be economically naïve. It can take several specific forms, from the basically reasonable to the utterly ridiculous. On the former end is “peak oil”, the point at which we reach a maximum rate of oil extraction. We’re actually past that point in most places, and it won’t be long before the whole world crosses that line. So yes, we really are running out of oil, and we need to transition to other fuels as quickly as possible. On the latter end is the original Mathusian argument (we now have much more food per person worldwide than they did in Malthus’s time—that’s why ending world hunger is a realistic option now), and, sadly, the argument Mark Buchanan made a few days ago. No, you don’t always need more energy to produce more economic output—as Krugman’s example cleverly demonstrates. You can use other methods to improve your energy efficiency, and that doesn’t necessarily require new technology.

Here’s the part that Krugman missed: Even if we need more energy, there’s plenty of room at the top. The total amount of sunlight that hits the Earth is about 1.3 kW/m^2, and the Earth has a surface area of about 500 million km^2, which is 5e14 m^2. That means that if we could somehow capture all the sunlight that hits the Earth, we’d have 6.5e17 W, which is 5.7e18 kilowatt-hours per year. Total world energy consumption is about 140,000 terawatt-hours per year, which is 1.4e14 kilowatt-hours per year. That means we could increase energy consumption by a factor of one thousand just using Earth-based solar power (Covering the oceans with synthetic algae? A fleet of high-altitude balloons covered in high-efficiency solar panels?). That’s not including fission power, which is already economically efficient, or fusion power, which has passed break-even and may soon become economically feasible as well. Fusion power is only limited by the size of your reactor and your quantity of deuterium, and deuterium is found in ocean water (about 33 milligrams per liter), not to mention permeating all of outer space. If we can figure out how to fuse ordinary hydrogen, well now our fuel is literally the most abundant substance in the universe.

And what if we move beyond the Earth? What if we somehow captured not just the solar energy that hits the Earth, but the totality of solar energy that the Sun itself releases? That figure is about 1e31 joules per day, which is 1e27 kilowatt-hours per day, or seven trillion times as much energy as we currently consume. It is literally enough to annihilate entire planets, which the Sun would certainly do if you put a planet near enough to it. A theoretical construct to capture all this energy is called a Dyson Sphere, and the ability to construct one officially makes you a Type 2 Kardashev Civilization. (We currently stand at about Type 0.7. Building that worldwide solar network would raise us to Type 1.)

Can we actually capture all that energy with our current technology? Of course not. Indeed, we probably won’t have that technology for centuries if not millennia. But if your claim—as Mark Buchanan’s was—is about fundamental physical limits, then you should be talking about Dyson Spheres. If you’re not, then we are really talking about practical economic limits.

Are there practical economic limits to growth? Of course there are; indeed, they are what actually constrains growth in the real world. That’s why the US can’t grow above 2% and China won’t be growing at 7% much longer. (I am rather disturbed by the fact that many of the Chinese nationals I know don’t appreciate this; they seem to believe the propaganda that this rapid growth is something fundamentally better about the Chinese system, rather than the simple economic fact that it’s easier to grow rapidly when you are starting very small. I had a conversation with a man the other day who honestly seemed to think that Macau could sustain its 12% annual GDP growth—driven by gambling, no less! Zero real productivity!—into the indefinite future. Don’t get me wrong, I’m thrilled that China is growing so fast and lifting so many people out of poverty. But no remotely credible economist believes they can sustain this growth forever. The best-case scenario is to follow the pattern of Korea, rising from Third World to First World status in a few generations. Korea grew astonishingly fast from about 1950 to 1990, but now that they’ve made it, their growth rate is only 3%.)

There is also a reasonable argument to be made about the economic tradeoffs involved in fighting climate change and natural resource depletion. While the people of Brazil may like to have more firewood and space for farming, the fact is the rest of need that Amazon in order to breathe. While any given fisherman may be rational in the amount of fish he catches, worldwide we are running out of fish. And while we Americans may love our low gas prices (and become furious when they rise even slightly), the fact is, our oil subsidies are costing hundreds of billions of dollars and endangering millions of lives.

We may in fact have to bear some short-term cost in economic output in order to ensure long-term environmental sustainability (though to return to Krugman, that cost may be a lot less than many people think!). Economic growth does slow down as you reach high standards of living, and it may even continue to slow down as technology begins to reach diminishing returns (though this is much harder to forecast). So yes, in that sense there are limits to growth. But the really fundamental limits aren’t something we have to worry about for at least a thousand years. Right now, it’s just a question of good economic policy.