I'm Jonathan Tomkin from the University of Illinois.

This is the last lecture in this series. I'm going to be using this opportunity to

try and sketch out what the twenty-first century might look like in terms of

sustainability. Where are we headed?

Well, in the very first week I discussed the concept of growth curves and how that

there are some J growth curves and S growth curves.

J growth curves inevitably lead to a crash because whatever the current capacity is,

they always blow straight past it. Whereas, S growth curves can asymptote

toward a steady state towards that current capacity.

So, we might ask ourselves then if we're thinking about sustainability in the

twenty-first century, which of these two patterns we're more likely to be on.

Well, let's look at some real growth curves then.

This is from the United States. Energy use is flat, carbon dioxide

emissions are down, car trouble is down. Thanks to a transfer from coal to gas,

carbon dioxide emissions have dropped even as the price of energy is decreased.

Air pollution, like sulphur dioxide, is way down.

All this is despite the higher population and affluence as measured by GDP.

Note that this is not the prediction of an IPAT analysis.

Is this the whole story however? In some ways, the world is on two tracks.

There's the developed world track and the developing world track.

Developed world countries use lots of resources but at a static and sometimes

declining rate. In some cases, the amount of absolute

increase is zero. Japan's population, in fact, is predicted

to be a third lower in 50 years. And so, we could predict that Japan will be using

less resources then than it does now. These observations about developing world

have led to some new ideas. One of these is de-materialization.

This is the process by which less materials are used to deliver the same

function, Comparing electric file of a textbook

versus an actual physical book. This is an observed trend in the developed

world causing more efficient or even shared.

We see plenty of examples in this course of increased efficiencies,

There's better use of energy than there used to be in the past. And, there's less

use of water now in the United States than there was in the 1980's.

One estimate suggests that between 1980 and 2005, a French consumer enjoyed 50%

more affluence, but used only ten percent more energy.

So, this isn't just restricted to the United States, this is something that we

see in most developed economies. This isn't just a theory,

There are lots of other observations that line up with observe, with this idea.

Some commentators have spoken about peak oil but there is also peak travel, peak

steel, peak stuff. Take farmland in the United States.

We use less farmland now in the United States than we have in the last few

decades. In fact, peak farmland occurred in the

1950's. In fact, we use a comparable amount of

farmland as we did as at the start of the twentieth century.

The population of the United States has grown from 80 million to 300 million in

that time. I spoke previously about peak vehicle

travel in the United States. This isn't just restricted to the United

States, this is seen in many other countries as well, where it's been

observed in Britain, Germany, France, Japan.

From 2005 to 2008, every year in the United States, the amount of vehicle miles

traveled per person dropped. As of 2008, the average American is

driving about the same distance as they did in 1998.

We have this other idea of peak stuff. Beyond some point of consumption, people

stop buying new things. Maybe they don't have the space for it or

they don't have the need for more material objects in their, in their houses or in

their lives. The British environmentalist Chris

Goodall, for example, argues that people in the United Kingdom are actually

consuming less material goods now than they were in the 1990's.

According to data from the UK Office of National Statistics, the total material

requirement peaked at 2.17 billion tons in 2001 and has fallen by four%..

But in 2007, even though GDP rose over that period, so people were more affluent

but they had less things, they had less material things.

And, of course, material things have an impact on the environment.

Water use is down, travel and car ownership use is down, metal and paper use

is down, calorie consumption is down, and meat eat, eating is falling in the United

Kingdom. So, this is not the sort of trends that we

would associate with a J curve growth, an exponential growth.

This is true elsewhere as well. It's been observed in the US and Germany.

A good example of this, is that the amount of material going to landfills in the

United States is less now that it was in the past.

This is sometimes described as an environmental Kuznets curve.

In this case, the hypothesis is that as countries get wealthier they move through

a transition from when the began when they're poor, little pollutants are made.

And as they grow richer, more and more pollution is created.

But then past a certain threshold point, the amount of pollutants actually

decreases. So, if countries can transition from being

poor to being rich, they can move from being low polluting to high polluting and

back to low polluting. There are some different sets of data that

back this up. One famous example is sulfur dioxide.

As the United States got wealthier through the twentieth century, the amount of

sulfur dioxide emitted by American industry increased, but it peaked at

mid-century. Then,

Due to environmental laws and the concerns of individuals, it was decreasing all the

way through to today and it's continued to drop into the twenty-first century.

This is actually not just being observed in the United States.

Sulfur Dioxide emissions follow the same pattern all around the world.

There's this idea that if you have around $5,000 per person in per capita income,

you have a peak in sulfur dioxide production. And as you get wealthier than

that, the amount of sulfur dioxide that, that country produce actually starts to

fall again. We can apply this environmental Kuznets

curve to other environmental issues. One idea too, might be that we talked

about population. And it appears that population growth occurs in this narrow

band between wealthy and poor countries, as the country transitions to a more

developed state. This curve is controversial, however.

Notice how it is really empirical, It's based on observation not on

underlying theoretical concerns. It could be that it's not so much that

it's an increase in wealth that makes the environmental impact come down, but just

the passage of time. Of course, in the United States, we saw a

growth in wealth at the same time as the twentieth century progressed.

It could just be that as people became more enlightened, or technology improved,

or people became more socially aware of environmental issues, that there was the

demand to drop these emissions. And so, it's not actually to do with

wealth so much as a process of time. Another real concern is that it appears

that the environmental Kuznets curve doesn't apply to all environmental

variables. Let's think about calorie consumption, for

example, as we get wealthier that increases at a slower rate but it still

increases. More seriously, we might worry about

things like carbon dioxide production because that changes the nature of the

climate. That appears to increase at a slower and

slower rate but, nevertheless, still increase as countries become wealthier.

So, instead of seeing the curve bend back over, the curve remains quite flat and so

even wealthy countries are very polluting. In fact, the wealthier the country is, the

carbon dioxide the more it pollutes. Another good example might be steel

production. Steel production is showing no signs of a

Kuzenets curve right now. This could be due to building growth in

countries like China, but nevertheless, even developed countries like the United

States is still using a lot of steel. So, it could just be that the impact of

increase wealth, instead of moving down towards lower emissions, in another way

just reached a steady state. So, very wealthy countries are no worse

for the environment than merely wealthy countries.

Critics of peak stuff actually see these sorts of arguments as determinative.

They take the observation that developed countries use so much resources that any

talk about a dematerialization is overselling the case.

And that there might be a slight decrease or might be a slight change,

But really the rate is so high that this change is immaterial.

And there's another reason to think there won't be a universal Kuznets curve for the

twenty-first century. As we saw in the population module,

Most of the growth in the twenty-first century is going to happen in developing

countries. So, these are countries that have not

reached that point where they might start to decrease their levels of consumption.

Developed world countries use far more resources per person that the rate of

change in that growth is much lower than for developing countries.

So, developing countries are using less resources, but those resources are being

used at a growing rate. Perhaps, there is a hopeful side to this,

however. Developing countries needn't go through

the same development process that the industrialized countries of today had to

go through to reach their current state. They can leap straight into more efficient

developed technologies. Famously, many African countries aren't

installing fixed telephone wires, for example,

They moved straight to mobile phones. Other examples could include inproved

developments of farmland utilization. It's been estimated that if the

productivity of the world's farmers on an average basis was raised to the current

level of farmers in Iowa. A world of ten billion people could be fed

an American diet on about half the farm land being used now.

That's to show the incredible difference in yields and efficiency between the very

peak farmers and the world average. So, if we can use these sorts of

technologies and spread them to these quickly developing, quickly growing

developing countries, then we might be able to avoid some of the worse impacts of

industrialization. Another thing that I would add is that

this all appears to be somewhat organic, In a sense the system seems to run itself.

If we think about the twentieth century, we can see a history of world wars, other

disasters including flu pandemics, and social economic upheavals including the

Great Depression. All of these events, no matter how large

they were, no, did little more than slow down the trend lines that were established

for the countries that were developing through the twentieth century.

So, we might expect barring some global level catastrophe that these trends will

continue. We might have a recession, we might have a

local war, but in all of these cases, the trend line for the twentieth century

suggests that the twenty-first century's progress will just occur naturally from

the system itself. Produced by OCE, Atlas Digital Media at

the University of Illinois, Urbana-Champaign

Measuring Sustainability: The Future, Part 1

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