Why most resources don't run out

My Saturday essay in the Wall Street Journal on
resources and why they get more abundant, not less:

How many times have you heard that we humans are "using up" the
world's resources, "running out" of oil, "reaching the limits" of
the atmosphere's capacity to cope with pollution or "approaching
the carrying capacity" of the land's ability to support a greater
population? The assumption behind all such statements is that there
is a fixed amount of stuff—metals, oil, clean air, land—and that we
risk exhausting it through our consumption.

"We are using 50% more resources than the Earth can sustainably
produce, and unless we change course, that number will grow fast—by
2030, even two planets will not be enough," says Jim Leape, director general of the World
Wide Fund for Nature International (formerly the World Wildlife
Fund).

But here's a peculiar feature of human history: We burst through
such limits again and again. After all, as a Saudi oil minister
once said, the Stone Age didn't end for lack of stone. Ecologists
call this "niche construction"—that people (and indeed some other
animals) can create new opportunities for themselves by making
their habitats more productive in some way. Agriculture is the
classic example of niche construction: We stopped relying on
nature's bounty and substituted an artificial and much larger
bounty.

Economists call the same phenomenon innovation. What frustrates
them about ecologists is the latter's tendency to think in terms of
static limits. Ecologists can't seem to see that when whale oil
starts to run out, petroleum is discovered, or that when farm
yields flatten, fertilizer comes along, or that when glass fiber is
invented, demand for copper falls.

That frustration is heartily reciprocated. Ecologists think that
economists espouse a sort of superstitious magic called "markets"
or "prices" to avoid confronting the reality of limits to growth.
The easiest way to raise a cheer in a conference of ecologists is
to make a rude joke about economists.

I have lived among both tribes. I studied various forms of
ecology in an academic setting for seven years and then worked at
the Economist magazine for eight years. When I was an ecologist (in
the academic sense of the word, not the political one, though I
also had antinuclear stickers on my car), I very much espoused the
carrying-capacity viewpoint—that there were limits to growth. I
nowadays lean to the view that there are no limits because we can
invent new ways of doing more with less.

This disagreement goes to the heart of many current political
issues and explains much about why people disagree about
environmental policy. In the climate debate, for example,
pessimists see a limit to the atmosphere's capacity to cope with
extra carbon dioxide without rapid warming. So a continuing
increase in emissions if economic growth continues will eventually
accelerate warming to dangerous rates. But optimists see economic
growth leading to technological change that would result in the use
of lower-carbon energy. That would allow warming to level off long
before it does much harm.

It is striking, for example, that the Intergovernmental Panel on
Climate Change's recent forecast that temperatures would rise by
3.7 to 4.8 degrees Celsius compared with preindustrial levels by
2100 was based on several assumptions: little technological change,
an end to the 50-year fall in population growth rates, a tripling
(only) of per capita income and not much improvement in the energy
efficiency of the economy. Basically, that would mean a world much
like today's but with lots more people burning lots more coal and
oil, leading to an increase in emissions. Most economists expect a
five- or tenfold increase in income, huge changes in technology and
an end to population growth by 2100: not so many more people
needing much less carbon.

In 1679, Antonie van Leeuwenhoek, the great Dutch microscopist,
estimated that the planet could hold 13.4 billion people, a number
that most demographers think we may never reach. Since then, estimates have bounced around
between 1 billion and 100 billion, with no sign of converging on an
agreed figure.

Economists point out that we keep improving the productivity of
each acre of land by applying fertilizer, mechanization, pesticides
and irrigation. Further innovation is bound to shift the ceiling
upward. Jesse Ausubel at Rockefeller University calculates that the amount of land required to
grow a given quantity of food has fallen by 65% over the past 50
years, world-wide.

Ecologists object that these innovations rely on nonrenewable
resources, such as oil and gas, or renewable ones that are being
used up faster than they are replenished, such as aquifers. So
current yields cannot be maintained, let alone improved.

In his recent book "The View from Lazy Point," the ecologist
Carl Safina estimates that if everybody had the living standards of
Americans, we would need 2.5 Earths because the world's
agricultural land just couldn't grow enough food for more than 2.5
billion people at that level of consumption. Harvard emeritus
professor E.O. Wilson, one of ecology's patriarchs, reckoned that
only if we all turned vegetarian could the world's farms grow
enough food to support 10 billion people.

Economists respond by saying that since large parts of the
world, especially in Africa, have yet to gain access to fertilizer
and modern farming techniques, there is no reason to think that the
global land requirements for a given amount of food will cease
shrinking any time soon. Indeed, Mr. Ausubel, together with his
colleagues Iddo Wernick and Paul Waggoner, came to the startling conclusion that, even
with generous assumptions about population growth and growing
affluence leading to greater demand for meat and other luxuries,
and with ungenerous assumptions about future global yield
improvements, we will need less farmland in 2050 than we needed in
2000. (So long, that is, as we don't grow more biofuels on land
that could be growing food.)

But surely intensification of yields depends on inputs that may
run out? Take water, a commodity that limits the production of food
in many places. Estimates made in the 1960s and 1970s of water
demand by the year 2000 proved grossly overestimated: The world
used half as much water as experts had projected 30 years
before.

The reason was greater economy in the use of water by new
irrigation techniques. Some countries, such as Israel and Cyprus,
have cut water use for irrigation through the use of drip
irrigation. Combine these improvements with solar-driven
desalination of seawater world-wide, and it is highly unlikely that
fresh water will limit human population.

The best-selling book "Limits to Growth," published in 1972 by
the Club of Rome (an influential global think tank), argued that we
would have bumped our heads against all sorts of ceilings by now,
running short of various metals, fuels, minerals and space. Why did
it not happen? In a word, technology: better mining techniques,
more frugal use of materials, and if scarcity causes price
increases, substitution by cheaper material. We use 100 times
thinner gold plating on computer connectors than we did 40 years
ago. The steel content of cars and buildings keeps on falling.

Until about 10 years ago, it was reasonable to expect that
natural gas might run out in a few short decades and oil soon
thereafter. If that were to happen, agricultural yields would
plummet, and the world would be faced with a stark dilemma: Plow up
all the remaining rain forest to grow food, or starve.

But thanks to fracking and the shale revolution, peak oil and
gas have been postponed. They will run out one day, but only in the
sense that you will run out of Atlantic Ocean one day if you take a
rowboat west out of a harbor in Ireland. Just as you are likely to
stop rowing long before you bump into Newfoundland, so we may well
find cheap substitutes for fossil fuels long before they run
out.

The economist and metals dealer Tim Worstall gives the example of tellurium, a key
ingredient of some kinds of solar panels. Tellurium is one of the
rarest elements in the Earth's crust—one atom per billion. Will it
soon run out? Mr. Worstall estimates that there are 120 million
tons of it, or a million years' supply altogether. It is
sufficiently concentrated in the residues from refining copper
ores, called copper slimes, to be worth extracting for a very long
time to come. One day, it will also be recycled as old solar panels
get cannibalized to make new ones.

Or take phosphorus, an element vital to agricultural fertility.
The richest phosphate mines, such as on the island of Nauru in the
South Pacific, are all but exhausted. Does that mean the world is
running out? No: There are extensive lower grade deposits, and if
we get desperate, all the phosphorus atoms put into the ground over
past centuries still exist, especially in the mud of estuaries.
It's just a matter of concentrating them again.

In 1972, the ecologist Paul Ehrlich of Stanford University came
up with a simple formula called IPAT, which stated that the impact of
humankind was equal to population multiplied by affluence
multiplied again by technology. In other words, the damage done to
Earth increases the more people there are, the richer they get and
the more technology they have.

Many ecologists still subscribe to this doctrine, which has
attained the status of holy writ in ecology. But the past 40 years
haven't been kind to it. In many respects, greater affluence and
new technology have led to less human impact on the planet, not
more. Richer people with new technologies tend not to collect
firewood and bushmeat from natural forests; instead, they use
electricity and farmed chicken—both of which need much less land.
In 2006, Mr. Ausubel calculated that no country with a GDP per head
greater than $4,600 has a falling stock of forest (in density as
well as in acreage).

Haiti is 98% deforested and literally brown on satellite images,
compared with its green, well-forested neighbor, the Dominican
Republic. The difference stems from Haiti's poverty,
which causes it to rely on charcoal for domestic and industrial
energy, whereas the Dominican Republic is wealthy enough to use
fossil fuels, subsidizing propane gas for cooking fuel specifically
so that people won't cut down forests.

Part of the problem is that the word "consumption" means
different things to the two tribes. Ecologists use it to mean "the
act of using up a resource"; economists mean "the purchase of goods
and services by the public" (both definitions taken from the Oxford
dictionary).

But in what sense is water, tellurium or phosphorus "used up"
when products made with them are bought by the public? They still
exist in the objects themselves or in the environment. Water
returns to the environment through sewage and can be reused.
Phosphorus gets recycled through compost. Tellurium is in solar
panels, which can be recycled. As the economist Thomas Sowell wrote
in his 1980 book "Knowledge and Decisions," "Although we speak
loosely of 'production,' man neither creates nor destroys matter,
but only transforms it."

Given that innovation—or "niche construction"—causes ever more
productivity, how do ecologists justify the claim that we are
already overdrawn at the planetary bank and would need at least
another planet to sustain the lifestyles of 10 billion people at
U.S. standards of living?

Examine the calculations done by a group called the Global Footprint Network—a think tank founded
by Mathis Wackernagel in Oakland, Calif., and supported by more
than 70 international environmental organizations—and it becomes
clear. The group assumes that the fossil fuels burned in the
pursuit of higher yields must be offset in the future by tree
planting on a scale that could soak up the emitted carbon dioxide.
A widely used measure of "ecological footprint" simply assumes that
54% of the acreage we need should be devoted to "carbon
uptake."

But what if tree planting wasn't the only way to soak up carbon
dioxide? Or if trees grew faster when irrigated and fertilized so
you needed fewer of them? Or if we cut emissions, as the U.S. has
recently done by substituting gas for coal in electricity
generation? Or if we tolerated some increase in emissions (which
are measurably increasing crop yields, by the way)? Any of these
factors could wipe out a huge chunk of the deemed
ecological overdraft and put us back in planetary credit.

Helmut Haberl of Klagenfurt University in Austria is a rare
example of an ecologist who takes economics seriously. He points out that his fellow ecologists have been
using "human appropriation of net primary production"—that is, the
percentage of the world's green vegetation eaten or prevented from
growing by us and our domestic animals—as an indicator of
ecological limits to growth. Some ecologists had begun to argue
that we were using half or more of all the greenery on the
planet.

This is wrong, says Dr. Haberl, for several reasons. First, the
amount appropriated is still fairly low: About 14.2% is eaten by us
and our animals, and an additional 9.6% is prevented from growing
by goats and buildings, according to his estimates. Second, most
economic growth happens without any greater use of biomass. Indeed,
human appropriation usually declines as a country industrializes
and the harvest grows—as a result of agricultural intensification
rather than through plowing more land.

Finally, human activities actually increase the production of
green vegetation in natural ecosystems. Fertilizer taken up by
crops is carried into forests and rivers by wild birds and animals,
where it boosts yields of wild vegetation too (sometimes too much,
causing algal blooms in water). In places like the Nile delta, wild
ecosystems are more productive than they would be without human
intervention, despite the fact that much of the land is used for
growing human food.

If I could have one wish for the Earth's environment, it would
be to bring together the two tribes—to convene a grand powwow of
ecologists and economists. I would pose them this simple question
and not let them leave the room until they had answered it: How can
innovation improve the environment?