Unit 2
Environmental Problems, Their
Causes, and Sustainability
Exponential Growth
• When the quantity increases at a
constant rate per unit time.
• Is deceiving because it starts off slowly,
but after a few doublings it
grows to enormous
numbers
What will the graph look like?
Human Population Growth
• Between 1950 and 2004 the world’s population
increased from 2.5 billion to 6.4 billion.
• By 2008 there were 6.7 billion people on the
planet.
• These people consume vast amounts of food,
water, raw materials, and energy and in the
process produce huge amounts of pollution and
wastes.
• U.S. & World Population Clocks
• 8/23/11
U.S. 312,052,911
World 6,957,415,666
• The exponential rate of global
population growth has declined since
1963. (why?)
• No one knows how many people the
earth can support.
• Not all hope is lost…. There are several
solutions that could be implemented in
order to fix the damage done to the
planet.
2-1 Living More Sustainably
• Humans are dependent on the environment for:
water, food, shelter, energy and everything we need
to stay alive and healthy
• Environment = every thing around us.
– Includes :
• All the living and nonliving things with which we interact
• The relationships the connect us with one another
Plants & animals
= living parts
Water, rocks, atmosphere,
soil etc. = nonliving parts
• Environmental Science = An
interdisciplinary study of how humans
interact with the environment of living and
nonliving things.
– Integrates ideas from:
• Natural sciences (biology, chemistry, geology)
• Social Sciences (geography , economics, political
science and demography)
• Humanities (philosophy and ethics)
• Ecology = The biological science that studies how
organisms interact with their environment and
with each other.
• Main focus of Ecology is the study of
ecosystems.
– Ecosystem = a set of organisms interacting with
one another and with their environment of
nonliving matter and energy within a defined
area.
• Environmentalism = a social movement
dedicated to protecting the earth’s lifesupport systems for us and all other forms
of life.
– It is practiced more in the political and ethical arenas
than in the area science.
• Sustainability = the ability of earth’s various
natural systems and human cultural systems and
economies to survive and adapt to changing
environmental conditions indefinitely.
– How the planet can adapt and survive what we do to
it.
• Natural Capital = The natural resources
and natural services that keep organisms
alive and support our economies.
– Natural resources are materials and energy
in nature that are essential or useful to
humans. (renewable = air, water, soil, plants
and wind and nonrenewable = copper, oil
and coal)
– Natural Services are functions of nature,
such as purification of air & water, which
support life and human economics.
Air
Air Purification
Renewable Energy
(Sun, Wind, Water
flows)
Climate Control
UV Protection
(Ozone Layer)
Life (Biodiversity)
Population Control
Water
Pest Control
Water Purification
Waste Treatment
Non-Renewable
materials (iron, sand)
Natural oil
Soil
Soil Renewal
Gas
Natural Services
Food Production
Nutrient Recycling
Non-Renewable Energy
(Fossil Fuels)
Natural Resources
Land
Coal Seam
• Nutrient Cycling – the circulation of chemicals
necessary for life. (carbon cycle, water cycle,
nitrogen cycle)
• Solar capital is what sustains our natural
capital.
• Without solar energy there would be no
photosynthesis and our planet’s temperature
would be too cold for life as we know it.
• Thus, our lives and economies depend on
energy form the sun (solar capital) and natural
services (natural capital) provided by the earth.
• Humans need to recognize than many human
activities can degrade natural capital by using
renewable resources faster than they can be
replaced by nature.
• Example – clear cutting forests and over fishing oceans
• It is important to find solutions to the
environmental problems we are causing.
– Government laws & regulations may need to be implemented
• Sometimes solutions may involve conflicts.
– Companies or people affected may be upset with the
regulations & laws
• Trade offs and compromises must be made.
• Environmentally sustainable societies
protect natural capital and live off its
income.
• Example: You win $1 million in the lottery.
– Choice #1 – live off the interest of $100,000/year) –
you will have enough money to live indefinitely
– Choice #2 – spend $200,000/year – you will go
bankrupt in seven years.
– Choice #3 – spend $110,000/year – you will go
bankrupt in 18 years.
• Lesson learned --- Protect your capital and live
off the income it provides.
• If we deplete our natural capital, we will
move from a sustainable to an unsustainable
lifestyle.
• Living sustainably means living off natural
income and preserving the earth’s natural
capital.
• According to scientific evidence, we are
living unsustainably by wasting, depleting,
and degrading the earth’s natural capital at
an exponentially accelerating rate.
2-2 Population Growth, Economic Growth
Economic Development, & Globalization
• Gross Domestic Product (GDP) = annual
market value of all the goods and
services of a country.
• Per capita GDP = a country’s economic
growth per person.
The gross domestic product (GDP) is a measure of a
country's overall official economic output. It is the
market value of all final goods and services officially
made within the borders of a country in a year.
• Economic growth provides people with more
goods and services, economic development
uses economic growth in order to improve
living standards.
• UN classifies countries on their degree of
industrialization, per capita GDP and the
countries purchasing power.
– Developed Countries= US, Canada, Japan,
Australia, New Zealand and most European
countries
– Developing Countries= Africa, Asia, Latin America
2-3 Resources
• Resource = anything obtained from the environment
that we need or want
• Conservation=managing the natural resources in
order to waste less and save more.
• Some resources are directly available for our use
(solar energy, fresh air, wind, fresh water, fertile soil,
plants)
• Other resources we have to put
effort into getting (petroleum,
natural gas, metals)
• Globalization – The process of social,
economic, and environmental global changes
that lead to an increasingly interconnected
world.
• Factors that accelerate globalization:
– Information and communication technologies
– Human Mobility
– International trade and investments
• Perpetual Resources = renewed continuously
(solar energy)
• Renewable Resources = can be replenished fairly
quickly (hours to hundred of years). Ex; forests,
grasslands, fisheries, freshwater, fresh air, fertile
soil).
• Sustainable yield = refers to the highest rate at
which we can use a renewable resource without
reducing its supply. If we exceed the resource’s
sustainable yield, then environmental
degradation occurs (we use up the resources
faster than it can be replaced by nature).
• Three types of properties exist:
1) Private Property – owned by individuals or firms
2) Common Property –rights to the land are held by a
large group of individuals (1/3 of the US is owned by
all US citizens and held and managed by the
government)
3) Open Access Renewable Resources – owned by no
one and available for use by anyone – air,
underground water supply, open ocean,
“Tragedy of the Commons”
• In 1968 Biologist Garrett Harden called the
degradation of the common property and
open access resources the “Tragedy of the
Commons”.
• It occurs because each person thinks that the
small amount of disturbance or use of the
resources that he/she does will not cause
enough harm to the environment to really
matter.
Solution to the “Tragedy of the
Commons”
• Use the resources wisely at a rate well below
their sustainable yield by reducing their use.
• Regulate the access to the resources
• or both
• Ecological Footprint – Our Environmental Impact
• Per capita Ecological Footprint – The amount of
biologically productive land and water needed to
supply each person with the renewable resources
they use and to absorb or dispose of the wastes from
such resource use.
– In other words the measure of how much of earth’s
natural capital and biological income each of us uses.
The Ecological Footprint of each person in developed
countries is large compared to that in developing
countries.
www.footprintnetwork.org/en/index.php/GFN/page/c
alculators. (estimate your EF)
• Nonrenewable Resources – resources we can
deplete.
• See figure 1-6 on page 9
• These resources become economically
depleted when it costs more to extract them
that what they are worth.
• Once they are depleted we have 6 choices:
–
–
–
–
–
–
Try to find more
Recycle/reuse existing supplies
Waste less
Use less
Try to develop a substitute
Wait millions of years for more to be produced
Resources
Nonrenewable
Perpetual
Direct Solar
energy
Fossil
fuels
Winds, tides,
flowing
water
Metallic
Minerals
Renewable
Fresh
Air
Fresh
Water
Fertile
Soil
Plants &
Animals
(biodiversity)
Nonmetallic
Minerals
2-4 Pollution
• Pollution is the presence of substances at high
enough levels in air, water, soil, or food to
threaten health, survival, or activities of
humans or other organisms.
• Most of the pollution occurs in urban or
industrialized areas.
• Pollutants we produce come from two types
of sources; Point Sources and Nonpoint
Sources
1. Point Sources of pollution are single, identifiable
sources. Ex: a smokestack of a coal burning
power plant
2. Nonpoint Source of pollution are dispersed and
often difficult to identify. Ex: Pesticides sprayed
into the air or blown by the wind into the
atmosphere.
• Effects of Pollutants:
– They can disrupt or degrade life-support systems for
humans and other species.
– They can damage wildlife, human health and property.
– They can be nuisances such as noise and unpleasant
smells, tastes and sights
• Two basic approaches to deal with pollution:
1. Pollution Prevention (input pollution control)
which reduces or eliminates the production of
pollutants
2. Pollution Cleanup (output pollution control)
which involves cleaning up or diluting pollutants
after they have been produced.
• Three problems of relying on Clean-up:
1. A temporary solution as long as
pollution continues
2. Removes pollutants from one area but
causes pollution in another area.
3. It costs too much to remove enough of
the pollutants
• Both prevention and clean up are
important but more emphasis has to be
made on prevention
2-5 Environmental and Resource
Problems: Causes and Connections
• Major Environmental Problems
(figure 1-9 pg12)
– Biodiversity depletion
– Air pollution
– Water pollution
– Waste production
– Food supply problems
• Major Causes of Environmental Problems
(figure 1-10 page 13)
– Population growth
– wasteful resource use
– Poverty
– Poor environmental accounting
– Ecological ignorance
• Poverty is a major threat to human health and
the environment.
– In the need for short term survival they deplete and
degrade the resources; forests, soil, water, and fuel
– They don’t have the luxury of worrying about long
term environmental quality
– Live and work in unhealthy and unsafe working
conditions
– They have many children to help them grow food and
do work and care for them in their old age
– Short life spans- mainly due to (1) malnutrition (2)
usually nonfatal infectious diseases (3) lack of access
to clean drinking water (4) severe respiratory disease
from poor air quality
• Affluenza  unsustainable addiction to
overconsumption and materialism exhibited in
the lifestyles of affluent consumers in the US
and other developed countries.
• “Too many people spend money they haven’t
earned to buy things they don’t want, to
impress people they don’t like,” Will Rogers
• Between 1998 and 2001 more people
declared bankruptcy than graduated
from college.
• Affluent countries have more money for
improving environmental quality.
• In the US air is cleaner, water purer, river/lakes
are cleaner and food supply is more abundant
since the 1970’s- We also have more efficient
technologies and more forests.
• Average US citizen consumes 35 times as much
as the average citizen of India and 100 times as
much as the average person in the poorest
countries.
2-6 Is Our Present Course Sustainable?
• Good and Bad Environmental News
– Two Groups/ Point of Views:
1) Technological Optimists – tend to overstate
the situation – saying things are not as bad as
they seem- our technologies and advances
can help us clean up the pollution and fix
things.
2) Environmental Pessimists – Overstate the
problem making the environmental situation
seem hopeless.
• Your environmental worldview is:
– How you think the world works
– What you think your role in the world should be
– What you believe is right or wrong environmental
behavior
•People who have different environmental
worldviews can take the same data and come
up with different conclusions because they
start with different assumptions and values.
• Three Environmental Worldviews:
1. Planetary Management Worldview
a. Humans are in charge of nature
b. We won’t run out of resources because
we can develop new ones
c. potential for economic growth is
unlimited
d. Our success depends on how well we
manage earth’s life-support systems for
our benefit
2. Stewardship Worldview
1. Humans are the most important species
but we have the ethical responsibility to
care for nature
2. We will probably not run out of resources
but we should not waste them
3. We should encourage environmentally
beneficial forms of economic growth
4. Our success depends on how well we
manage the earth’s life-support systems
for our benefit AND the rest of nature.
3. Environmental Wisdom Worldview
a. Nature exists for all species not just us- we
are not in charge of Earth.
b. Earth’s resources are limited and they are
not only for us
c. We should encourage earth sustaining
forms of economic growth
d. Our success depends on learning how the
earth sustains itself and following that.
• Most Serious Environmental Problems:
– Poverty & Malnutrition
– Smoking
– Infectious diseases
– Water shortages
– biodiversity loss
– Climate changes
• Economic rewards (government
subsidies and tax breaks) are used to
ENCOURAGE environmentally beneficial
and sustainable forms of economic
growth.
• Economic penalties (government taxes
and regulations) are used to
DISCOURAGE environmentally harmful
and unsustainable forms of economic
growth.