Transcript Introduction to Environmental Science

Introduction to Environmental
Systems
IB Syllabus: 3.1.1, 3.2.2, 3.8.1,
4.2.1, 6.1.2
Chapters – 1,2,3
Syllabus Statements
• 3.1.1 – Describe the nature and explain the
implications of exponential growth in human
populations
• 3.2.2 – Define the terms renewable, replenishable,
and non-renewable natural capital
• 3.8.1 – Explain the concept of an ecological
footprint as a model for assessing the demands
that human populations make on their environment.
• 4.2.1 – Identify factors that lead to loss of diversity
• 6.1.2 – Describe how human activities add to
greenhouse gases
Vocab
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Gaia
Society
Sustainability
MEDC
LEDC
Biosphere
Interconnectedness
• Study of the Environment and the human
interaction with it.
• Interdisciplinary Investigations
– Biology, Chemistry, Physics, Geology,
Meteorology, Mathematics, Economics,
Politics, History, Ethics, etc.
– (1) How does the earth work?
– (2) How are we effecting the earth?
– (3) How do we deal with current
environmental problems?
Gaia Hypothesis
• Developed by James
Lovelock
• Named after the Greek
Goddess of Earth
• States that the Earth is a
living organism in which
feedback mechanisms
maintain equilibrium
• The interconnected living
earth is the Biosphere
The two sides
• Earth provides
1. solar capital – energy
2. natural capital – all other resources
3. energy Resources
• Humans need
1. basic common needs
2. Food, Water, Air, Shelter
The Goal: Sustainability
• An environmentally sustainable society will
satisfy the basic needs of its members into
the future without:
1. Depleting or degrading natural
resources
2. Preventing current or future
generations of all species from meeting
their basic needs
Facts on the Condition of the
Environment
Current Facts: #1
World Population is Increasing
Modern humans around for past 200,000 – 400,000 years
Human Impacts on the Environment
•Increasing
Human
Numbers
Human Impacts on the
Environment
• Most populous countries:
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1) China
2) India
3) United States
4) Indonesia
5) Brazil
1,374,853,000
1,155,011,000
309,163,000
258,825,000
195,580,000
Source: US Census Bureau, Global Population Profile: 2002
Current Facts: #2
Unequal Global Distribution of $$$
• Historically: HAVES vs. HAVE-NOTS
• Developed countries (MEDCs)
– US, Australia, European nations, Japan
– 1.4 billion people (19% world population)
– 85% wealth, 88% resource use, 75% pollution
• Developing countries (LEDCs)
– African, Asian & Latin American nations
– 5.5 billion people (81% of world population)
– 15% wealth, 12% resource use, 25% pollution
Population, Resources, and the
Environment
• The contrast between less developed and
highly developed countries is great:
World Population Distribution
Current Facts: #3
We are Polluting our Planet
• Pollution = any addition to water air or soil that
threatens the health, activities or survival of any
organism
1. enter environment naturally - volcanoes
2. anthropogenic (human) sources automobiles
3. Point (one location) vs. Nonpoint (spread out)
sources
• How can we minimize pollution effects?
Endocrine disrupters
• Chemical pollutants –
Endocrine disrupters
interfere with hormone
production & function
within the body.
• Hormones are chemical
messengers that
regulate growth,
reproduction, & other
functions.
Atmospheric effects
• Ozone Depletion – CFCs (man made compounds)
deplete stratospheric ozone
• Ozone naturally blocks UV radiation
• Since 1987, 167+ nations have banned use of CFCs
and other ODCs
• Global Warming – Human activities like combustion
of fossil fuels and agriculture put out greenhouse
gasses like CO2, CH4, and NO2
• Kyoto protocol (1997) was proposed legislation to
have worldwide decrease of emissions
• Hasn’t happened yet…
Current Facts: #4
We are effecting species
• Declining Bird populations for the past 2
decades
• Tropical Migrants like songbirds most effected
• Forest fragmentation – division of unbroken
areas into smaller chunks
• Edges are closer which increases vulnerability,
chance of invasive species, and habitat
degradation
• Increases in nest parasitism occuring
Topical Rainforests
Tropical Forest Destruction
Tropical Rainforest Destruction
• 1990’s Brazil lost 2 million hectares (5 million
acres) per year
• This effects the neotropical songbird migrants
• Slash and burn agriculture = used to temporarily
increase soil fertility – but increases
sedimentation of local watersheds
• Burning increases global warming as well
• Capitalize on resources once if burnt or
harvested unsustainably
• Better options – bioprospecting & ecotourism
Introducing Invasive Species
• Species brought by human
activity – ballast water,
agricultural shipments, pet
trade escapees
• Zebra Mussel – native to
Caspian Sea
• $5 billion annually in damage in
US
• Worldwide 10-30% of species
in an area are introduced
Reintroducing Wolves into
Yellowstone
• Originally ranged from Mexico to Greenland
• In the 1930’s government sponsored program to assist
ranchers in removing “threatening wolves”
• By 1960 only remaining wolves in lower 48 states in
Minnesota
• In 1995 & 1996 two populations captured in Canada &
released now up to 300 individuals
• Elk had overgrazed the habitat in the absence of
predators and population booms caused thousands to
starve in lean years
• Wolves are a “keystone species” and trophic cascade
has effected 100’s of species restoring balance to the
ecosystem
Current Facts: #5
Increases in Globalization
• Process of Global social, economic and
environmental change that increases
integration of the world
• 1950-2002  Global trade 516%,
• Technological connection – 1/11 people in
world on the internet
• Environment – organisms transported
around globe, pollutants in environment
FTAA = Free Trade
Area of the Americas
Current Facts: #6
Resource depletion
• Renewable vs. Replenishable vs.
nonrenewable resources
– Renewable  Alive and grows back - trees
– Replenishable  Not alive but regenerates - fresh
water
– Nonrenewable  Once it’s used it’s gone - metals
– Environmental degradation compounds problems
even further
Georges Bank Fishery
• Closed in 1994
• Fish stocks declining for decades
• Too many boats, too much technology, not
enough fish
• Now populations at half of sustainable levels
• Overfishing is a problem worldwide – 80% of
world fish stocks are over exploited already
• Tragedy of the Commons
In the last 30 years we have consumed 1/3 of all the resources on the planet
1/3!!!
What is our ecological footprint?
– Amount of land needed to provide resources
needed for a person or country
– If everyone on earth consumed like americans
we’d need many times the earth’s area for
support
– Incidentally how many earths do we have?
Ecological footprint
The growth of the
Environmental Movement
• Remember that all of this is a choice
• The Green movement is upon us
• The current administration believes in and
is trying to fight against climate change
• …
Is our Society Sustainable?
• No readily accepted view
-- Humans are smart enough to deal with what
ever problems the degradation of earth may throw at
us
– We are in serious trouble and on our current course
the environment will be destroyed beyond repair in
the near future
• A clash of worldviews – how we see the
world, and ethics – the right and wrong
environmental behavior
The Worldviews
Planetary Management
• We’re in charge of
nature
• Resources are
unlimited
• All growth is good
• Our success depends
on our control
Environmental
Management
• Nature doesn’t just
exist for us
• Resources are limited
• Growth may be bad
• Success depends on
acting with env.
wisdom
Potential changes for the Future
1.
2.
3.
4.
Pollution prevention not Clean up
Waste reduction not Disposal
Protecting habitats not Species
Environmental restoration not
Degradation
5. More efficient resource use not
increased use
6. Population stabilization not Growth
Your Challenge
This course will not tell you how to
think about the environment. Rather
it will provide you with the background
information necessary to make your
own decision about how you will
impact the environment in the future.