Transcript APES 1 Sustainability

A P Environmental Science
(APES)
What’s the use of a house if you
don’t have a decent planet to put it
on?
Henry David Thoreau
Humans and Sustainability:
Chapter 1: Environmental Problems,
Their Causes and Sustainability
Chapter Overview Questions
• What are the main themes of this book?
• What keeps us alive? What is an
environmentally sustainable society?
• How fast is the human population growing?
• What is the difference between economic
growth, economic development, and
environmentally sustainable economic
development?
Chapter Overview Questions (cont’d)
• What are the harmful environmental effects of
poverty and affluence?
• What three major human cultural changes
have taken place since humans arrived?
• What are the four scientific principles of
sustainability and how can we use them and
shared visions to build more environmentally
sustainable and just societies during this
century?
Key Concepts
• Nature has sustained itself for billions of years
by relying on solar energy, biodiversity, and
nutrients cycling
• Lives and economies depend on energy from
the sun, natural resources and natural services
(natural capital)
Connections in Nature
Environment- living and nonliving components
that set stage for life
Environmental Science- intergrated studies of:
• natural science (biology, chemistry, geology)
• social science (geography, economics, political
science)
• humanities (philosophy, ethics)
ENVIRONMENTAL SCIENCE
Earth's Life-Support System
Human Culture Sphere
Air
(atmosphere)
Water
(hydrosphere)
Population
Size
Worldviews
and Ethics
Soil and
rocks
(lithosphere)
Life
(biosphere)
Economics
Politics
Ecology and Environmental Science
Ecology- study of interaction of organisms with
each other and their environment
Species- organisms capable of reproducing and
producing viable young
Ecosystem- defined area within which organisms
interact with each other and their environment
(smaller slice of a biome)
Environmentalism- social movement dedicated to
protecting life support systems for all species
3 Goals of Environmental Science
• Learn how nature works
• Understand how we interact with the
environment
• Find ways to deal with environmental issues
to live more sustainably
3 Principles of Sustainability
Long-term sustainability rests on:
• Solar energy
• Biodiversity
• Nutrient (chemical)
cycling
Solar Energy
• Warms planet, necessary for photosynthesis
(essential for most life on planet)
• Powers indirect forms of solar energy- wind,
flowing water (hydroelectric power)
Biodiversity
• (Astounding) variety of life
• Natural systems that support life (biomes)
• Natural services such as:
topsoil renewal
pest control
air and water purification
Chemical Cycling
• Indefinite recycling of chemicals from
environment through organisms and back
again
• AKA nutrient recycling
CHECKPOINT
1. What is sustainability and why
should we care about it?
2. What are 3 principles nature has
used to sustain itself for billions of
years?
3 Components of Sustainability
• Natural capital
• Natural resources
• Natural services
Natural Capital
• Natural resources and natural services
• Supports Earth’s diversity
• Provided by solar energy
ex: ozone layer (resource) + UV protection(service)
Natural Resource
• Material from environment that meet needs/wants
• Vary in renewal time after use:
 perpetual- continuous supply (sunlight)
 renewable- days to years for renewal (some fish
species)
*sustainable yield- highest rate renewable resource
can be used without reducing it
 nonrenewable- exist in fixed stock in terms of
human time (energy, metallic minerals, nonmetallic
minerals)
The Tragedy of the Commons
(overexploiting shared renewable resources)
described by biologist, Garrett Hardin
• Open-access renewable resources: owned by
noone, used by anyone (air, open ocean, marine
life)
• Leads to: “If I don’t use the resource, someone
else will and any damage I do to the resource
will be too small to matter”
• Results in: exploitation and possibly complete
degredation of common resource (noone can
use it anymore)
Example of Tragedy of Commons
Imagine a field of grass shared by 6 farmers, each with one cow
Each cow currently produces 20 liters of milk per day The carrying
capacity of the commons is 8 cows. For each cow above 8, the milk
production declines by 2 liters (due to overgrazing, there is less grass
for each cow: less grass, less milk!).
Total daily milk production for the commons: 120 liters
Are the farmers satisfied with 1 cow apiece? Not if they are
want more liters of milk (and more profit)!
I need a new
tractor. Better
graze another
cow
Total daily milk production for the commons: 140 liters (7 cows)
We are now at the carrying capacity -- do we stop?
Not if I can make a little more profit!
Wait! If you can
graze another
cow, so can I.
Total daily milk production for the commons: 160 liters (8 cows)
And so...
Me too!
Me too!
Me too!
Me too!
...Until there was no more grass for any of the cows
The End
Natural Services
• Natural consequence of energy flow
• Provide ecological services
• Purify, recycle and detoxify
ex: bee pollination of crops
rocks, sand purifying stream water
marshes controlling flood waters
soil formation from eroding rock,
decaying organisms
Sustainability- Altogether Now
CHECKPOINT
1. Create a concept map showing a
connection between the
following terms: perpetual,
renewable and nonrenewable
energy.
2. Give examples of each type of
resource.
Humans and Sustainability
• Economic growth- increase in nation’s output
of goods, sevices
• Gross domestic product (GDP)- annual
market value of goods, services produced
within nation (measure of economic growth)
• Per capita GPD- GPD ÷ total population at
midyear (measures economic
growth/person)
Sustainability and Economic
Development
Nations are classified as:
• More-developed- high average income
*19% of population use ≈88% of planet’s
resources; produce ≈75% of planet’s waste
(US, Canada, Japan, Australia)
• Moderately-developed (China, India, Brazil)
• Less-developed- middle-low income (poverty)
*81% of world’s population
(Nigeria, Ethiopia, Somalia)
Developed vs Less-Developed
Countries
Economics: Global View
CHECKPOINT
1. What is the difference between GDP and per
capita GDP?
2. Distinguish between more-developed and
less-developed countries?
Ecological Footprint
• Ecological footprint- amount of biologically
productive land and water required to
support an individual and absorb his/her
pollution
• Per capita ecological footprint- average eco
footprint of an individual in an area
(calculate your own footprint at
www.myfootprint.org/)
Ecological Footprint
Natural Capital Degradation
• unsustainable resource use by wasting,
depleting and degrading natural capital
• accelerating exponentially
• includes:
air pollution, aquifer depletion, declining
ocean fisheries, species extinction
desertification
Natural Capital Degradation
Ecological Tipping Point
• threshold level at which natural capital
degradation is irreversible
• current tipping points:
1. collapse of some fish populations due to
overfishing
2. premature extinction of species due to
overhunting, habitat destruction
3. long-term climate change due to burning
fossil fuels
CHECKPOINT
1. Compare the total and per capita ecological
footprints of the United States and China.
Use the ecological footprint model to explain
how we are living unsustainably.
Pollution
• Contamination of resource that renders it
unsafe
• Major types: biodegradable, nondegradable
• Results in:
1. disruption of natural life-supports
2. damages life directly
3. create nuisances (unpleasant
smells, unwanted noise, etc)
Pollution Sources
• Point source: single, identifiable sources
(drainpipe of a factory, smokestack of a
power plant, exhaust pipe of car)
• Nonpoint source: dispersed, difficult to
identify (pesticides blown into air, runoff of
fertilizers from farming areas, litter on Tybee)
Dealing with Pollution
• Output pollution control/pollution cleanup:
cleaning or diluting pollution after it happens
• Input pollution control /pollution prevention:
reduces or eliminates production of
pollutants
Problems with Pollution Cleanup
1. Temporary solution (doesn’t address
unsustainable use of resource)
2. Often creates pollution in other areas
(burning , dumping or burying garbage)
3. Costly
4 Major Causes of Environmental
Problems
1.
2.
3.
4.
Exponential population growth
Unsustainable use of resources
Poverty
Excluding environmental costs from market
prices of goods
5. Conflicting worldview of environmental
ethics
1.Population Growth &
2.Unsustainable Resource Use
• ≈6.9 billion people on planet
• Humanity’s ecological footprint is close to
exceeding earths ecological capacity
• Can be slowed by economic development,
family planning, EDUCATION!
Exponential Growth
Black Death
Hunting and Gathering
Agricultural revolution
Industrial Revolution
3.Environmental Effects of Poverty and
Affluence
Poverty: inability to provide for daily needs
• affects ≈1 in 5 on planet
• prevents choice of environmental protection
over survival
• results in high rate of natural capital
degradation
Results of Poverty
Environmental Effects of Poverty and
Affluence (cont’d)
Affluence: lifestyle associated with developed
countries which results in:
• rapid unsustainable consumption of
resources
• generation of more pollutants
• large ecological footprint
• affluenza- addiction to buying more stuff
Upside to Affluence
• Access to education and technology
• Resources to protect natural capital
• Resources to reverse some affects of natural
capital degredation
4. Prices Vs Value of Natural Capital
• Prices of consumer goods and services do not
include harmful environmental costs
• Government subsidies may encourage
depletion and degradation of natural capital
• Consumers don’t “feel” the cost of goods to
the environment (so they keep wanting
more!)
5. Conflicting Worldviews of
Environmental Issues
Environmental ethics: beliefs about how to
treat environmental issues
• Planetary management worldview: man is in
charge of nature; nature exists to serve man
• Stewardship worldview: man has responsibility
to ethically manage nature
• Environmental wisdom view: nature exists for all
species, not just man. Our success depends on
knowing how life sustains itself
*Aldo Leopold- nature does not belong to man;
man belongs to nature
CHECKPOINT
1. What is poverty?
2. In what ways do poverty and
affluence affect the
environment?
3. Explain the problems we face by
not including the harmful
environmental costs in the prices
of goods and services.