Carrying capacity is the number of people the Earth can support indefinitely.
There is no fixed number, rather the capacity depends on the amount of resources consumed by each person
One simple way to look at carrying capacity is the Ecological Footprint
(developed by Bill Reese at UBC)
The ecological footprint is calculated by looking at a person's lifestyle to determine
resource use. The amount of land needed to produce these resources can then be calculated.
The Canadian, Italian and Swedish footprint:
Our newest estimates show that the average Canadian requires a little under 7 hectares of
biologically productive land and 1 hectare of biologically productive sea space to provide for his
or her current level of consumption.
These add up to 7.7 hectares or 77,000 square meters (770 times 100 meters)
or 15 typical soccer fields. In comparison, the average American lives on
a footprint about 30 percent larger, the average Italian on less than two third the size. The
average Swede occupies close to 6 hectares and the average Mexican 2.6 hectares. These figures
may still be underestimates of the ecologically productive areas truly necessary
to sustain these people.
Compared to the available eco-capacity...
Dividing all the ecologically productive land and sea on this planet by the number of people
inhabiting it, results in a statistical average of 2.2 hectares per person, less than one third
of what is necessary to accommodate a typical Canadian footprint. If we put aside,
as suggested by the Brundtland Report: Our Common Future, 12 percent of the biologically
productive space for preserving the other 30 million species with whom we share this planet,
the available space per capita shrinks to 2 hectares (Note: even though preserving 12 percent of the planet as
undisturbed habitat for other species would be politically astute, ecologically
it would still be insufficient). With the anticipated global population of 10 billion for the year 2050,
the available space will be reduced to 1.2 hectares, including the sea area.
Already, the average Italian uses 210 percent more than is available on a per capita basis worldwide,
or 320 percent more than is at hand per Italian within their national territory.
Sweden is among the lucky few countries who have ecological footprints that are smaller
than their ecologically productive space.
Worldwide, however, humanity's footprint may exceed global carrying capacity by
over 30 percent - in other words, humanity consumes more than what nature can regenerate and is
eating up the globe's natural capital stock. This points to the most pressing challenge of
today: reducing significantly human impact to allow present and future generations as well
as other species to have healthy lives.
So, based on the idea of an ecological footprint, the Earth will not be able to support
10 billion people using resources at the level of developed countries today.
Dr. Jones presented some evidence which led to different conclusions, so let's take another look at that evidence
Food
200 years ago Thomas Malthus developed a theory. Food production grows arithmetically,
while population grows geometrically. Therefore population will always outstrip food supply,
resulting in a population crash.
Since Malthus, many other people, including Paul Ehrlich, have predicted the same thing.
As Dr. Jones explained to you, none of these predictions has come true.
Instead, food production has managed to stay ahead of population growth. You saw all the graphs
of increasing yields of crops etc., but these graphs all ended in the mid 1970's, at the
peak of the Green Revolution.
But how has this come about, and will the trend continue?
The Green Revolution of the 1970's is over. Increasing amounts of fertiliser no longer
provide huge increases in productivity, and can barely maintain existing productivity.
To make matters worse, the amount and quality of land available for agriculture is
decreasing globally. In developed countries, urban sprawl covers up our best farmland.
Add in soil erosion and desertification from poor farming practices. Each year 6 million Ha of land becomes
desert, and an additional 21 million Ha provide no economic return. 29% of the Earth's land
area suffers slight, moderate, or severe desertification, while an additional 6% is severely
desertified.
Water
Part of the increased productivity of the Green Revolution was a result of improved irrigation of marginal lands.
In many areas, there is not enough water to continue with this irrigation. Aquifers in the
U.S. and globally are falling. The Colorado River no longer reaches the ocean.
Water consumption has tripled since 1950, and is still increasing. Only 2.5% of the water
on Earth is freshwater, and most of that is locked up in glaciers. Canada has a huge supply of
freshwater. Water export and diversion schemes abound, and many people have predicted that
the wars of the next century will be fought over water
Resources
Dr. Jones mentioned the 25 year rule, whereby we can always find enough reserves of a
resource for the next 25 years. The argument was simply that we've always found more and we always
will.
Well, we live on a finite planet. There is a fixed amount of every single non-renewable
resource, and once we use it up, no amount of searching will find more.
It will be a long time before we actually use up all the existing reserves of any resource,
but a more pressing concern is can we handle the impacts of finding and extracting the resource?
Dr. Jones correctly pointed out that scarcity increases the price of a resource, making it
worthwhile to spend more money looking for more in harder to reach places. The result is that
people go literally to the ends of the Earth hunting for valuable resources. This puts
incredible pressure on the few remaining wilderness areas.
Already the majority of the U.S. is criss-crossed by roads. The USFS is the world's largest
road-building agency. The same pattern is repeated around the world. First roads go in for
prospecting and exploration. If any minerals or fossil fuels are located, then mines and
wells go in. Even if nothing is found, the roads still allow more access for logging.
All of these calculations and arguments only consider the resources available for humans.
There are at least 30 million other species sharing the Earth with us, and competing for the
same resources. By the end of the 1980's, humans were already using about 40% of the Earth's
net primary productivity. As our demand for resources grows, we will take an ever increasing
share of the Earth's finite resources, leaving less and less for other species. Already we are
losing species at the rate of one an hour, meaning that we're living in the midst of the
greatest extinction in the history of the Earth.
Many of our resources are renewable (e.g. trees, fish), but that does not mean they will not
run out. To put it in economic terms, the present supply of fish is like money in the bank.
Every year more fish are produced, like interest on our money. As long as we only harvest
the interest, then we are using the resource at a sustainable level, and can keep on doing so
forever. As soon as we start to deplete the capital (whether natural or financial), we are
reducing the amount of the resource which will be available for future generations. The fisheries
on both coasts of Canada are perfect examples of this.
So I would conclude that resources are indeed finite, and if we don't change our consumption
then we will run out. Yes, substitutes are possible for many resources, but not for all.
There is no substitute for clean air or water, or for the biodiversity in an old growth forest.
Pollution
You saw some nice examples of how technology and legislation were able to clean up the River Thames
and reduce smog in London. Obviously in some cases technology in combination with appropriate
legislation can reduce pollution. The issue is much more complex than this, however.
The other argument that Dr. Jones used to support his assertion that pollution is not a
problem is that human life expectancy is steadily increasing. He showed a graph showing that
historically people died from causes related to air and water pollution, but now they die from
things such as cancer, heart disease, and stroke, all of which tend to strike older people.
This argument misses an important distinction between acute and chronic effects of pollution
It's easy to see there's a problem when thousands of people start dropping dead from smog.
This is an acute effect, one that harms you right away. It's much more difficult to see the
chronic effects of pollution. Everyday we are exposed to literally thousands of chemicals in
the air we breathe, the water we drink, and the food we eat. These chemicals are everywhere
on Earth. Even penguins in the Antarctic are exposed to these chemicals.
Many of these chemicals are known to cause cancer, birth defects, and countless other health
problems. The health effects of the majority of these chemicals have never even been studied.
Pollution is not simply a human problem. It affects every species on Earth. Beluga whales
in the St. Lawrence River have heavy metal concentrations so high that they are classified as
hazardous waste when they die. Pollution comes from everywhere: cars, factories, runoff from
fields, oil spills, mines. E.g. Britannia Mines
Conclusion: pollution is a steadily increasing problem with unknown effects.
Pollution can be controlled on a small scale, but at a global scale it is far too expensive
to eliminate pollution.
Economics
Economic theory states that in a free market, the laws of supply and demand will ensure that
the price for any good will end up being at the level which is optimal for society
Unfortunately, this hasn't happened. A major reason for this is that the price we pay for a
particular good does not include the full costs to society of producing that good.
We pay only for the cost of extracting the raw materials, manufacturing the good, transporting
it to the market, etc. Missing from this price are the externalities. All the environmental
and health effects associated with the good are paid for by society at large. When we buy a piece of
paper, we don't pay for the fish that were killed when soil from the clearcut destroyed their
spawning beds. We don't pay for the people who suffer from breathing problems caused by
the pollution from machinery involved in logging, trucking, and making the paper. We don't pay for
the aquatic organisms killed by effluent from the pulp mill. If all these externalities were
included, then the price for the paper would be higher, and we would consume less.
Technocratic Creed
Adequacy of science
Dr. Jones suggests that we know almost everything, and what we don't know isn't too important
-technology can fix the small mistakes we make.
In fact, we understand only a tiny fraction of how the world around us works. Out actions have many
unintended consequences, many of which we can't even imagine. E.g. DDT, CFC's,
We should instead employ the precautionary principle-if we don't know what the effects of an
action will be, then don't do it until we do.
Nature is the enemy
I agree that the natural world is indifferent to human survival and aspirations, but this
does not lead me to conclude that we must control nature. Nature provides us with everything we
need to survive. A much more certain way of ensuring our survival would be to avoid
interfering with natural processes as much as possible.
Dream of space
Space may well be our destiny, but we're not there yet. Until we find another habitable
planet and a reasonable means of getting there, we'd better take good care of the one we've got
Omnipotence of technology
Anything might be possible with technology, but only if we use it appropriately. The issue
is not what can technology do for us, but what can we do with technology?
Who controls technology?
Globalisation
Corporations are now bigger than countries and governments.
- The latest comparison shows that when the world's 100 largest entities are compared,
66 are corporations and only 34 are national governments, comparing gross corporate revenues
with government budgets (not GDP because most of the wealth represented by GDP is in private hands!).
- Only 7 national governments outrank the richest corporations.
- Each of the top three Exxon-Mobil, General Motors and Ford has more revenue than all but 7
of the 192 nations in the world.
- The top 6 Exxon-Mobil, GM, Ford, Mitsui, Daimler Chrysler and Mitsubishi together have more
annual revenues than any national state except the US.
- Wallmart is ahead of Canada
- The financial power of multinational corporations is now so great that they can exert
enormous influence for good or bad
- Corporations have only one legal mandate-to produce a profit for their shareholders.
They are not interested in whether or not technology is being used appropriately, only in
making money.
- We must rely on governments to ensure that technology is used appropriately
- Increasingly we are seeing power being concentrated in fewer and fewer hands. The WTO is a
prime example of this. An unelected panel of trade experts have the power to overrule laws
put in place by democratically elected governments. Any law which protects the environment,
workers' rights, etc. can be declared an unfair trade barrier.
- One of the scariest examples of the dangers of technology is genetic engineering. It is now
possible to take a gene from one organism and splice it into another totally different
organism. An alleged artist spliced a jellyfish gene into a rabbit to create a fluorescent rabbit.
That might be more sick than dangerous, but let's look at agriculture.
- Monsanto, a big chemical company, decided they could improve their market for herbicides by
genetically engineering crops to be resistant to their herbicide. The result
is Round-up Ready Canola. Now Monsanto was able to patent these seeds, and thus were able to force farmers to
buy a new supply of seed every year, rather than saving seeds from their crop.
This is a little hard to enforce, so now Monsanto has developed terminator technology. They can put a gene
into the seeds which ensures that the plants will not produce viable seeds.
- Can anyone see a problem with this?
- It is impossible to prevent the spread of this gene into the wild.
- Many of the foods we eat everyday contain GMO's, and no one knows the possible health effects.
- This is where the precautionary principle should come into play. Until we know the effects
of genetic engineering, we should be very careful about its use. WTO makes precautionary principle illegal.
The conclusion is that right now the trend is for multi-national corporations to have more and
more control over where and how technology is used. These companies are driven solely by a
desire for profit, with little or no concern for the social and environmental effects of their
actions. The average person has very little power to control how technology affects his or her life.
Conclusions
The Earth's cannot support a population of 10 billion people unless we can change our
patterns of resource consumption.
Technology has a great deal of potential both to harm and help people and the environment.
It is our choices about how we use technology that will determine the course of our future.
Next: The Betterment of the Human Condition (I)