1
Introducing Environmental Science and
Sustainability
Question of the day:

Define environmental sustainability.

List three things you do in your life that might
be considered a sustainable practice.
© 2012 John Wiley & Sons, Inc. All rights reserved.
Overview of Chapter 1





Human Impacts on The Environment
Population, Resources and the Environment
Sustainability
Environmental Science
Addressing Environmental Problems
© 2012 John Wiley & Sons, Inc. All rights reserved.
The Environment (Earth)


Life has existed on
earth for 3.8 billion yrs
Earth well suited for life
 Water
over ¾ of planet
 Habitable temperature,
moderate sunlight
 Atmosphere provides
oxygen and carbon
dioxide
 Soil with essential
minerals for plants
© 2012 John Wiley & Sons, Inc. All rights reserved.
Human Impacts on EnvironmentPopulation

Earth’s Human Population is at 6.9 billion


Growing exponentially
Expected to add
several billion more
people in 21st
century
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World Population Clock

http://www.census.gov/main/www/popclock.ht
ml
© 2012 John Wiley & Sons, Inc. All rights reserved.
Population

1 in 4 people live in
extreme poverty
 Cannot
meet basic
need for food, clothing,
shelter, health

Difficult to meet
population needs
without exploiting
earth’s resources
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Gap Between Rich and Poor

Highly Developed Countries (HDC)
 Complex
industrialized bases, low population
growth, high per capita incomes
 Ex: US, Canada, Japan
© 2012 John Wiley & Sons, Inc. All rights reserved.
Gap Between Rich and Poor

Less Developed Countries (LDC)
 Low
level of industrialization, very high fertility
rate, high infant mortality rate, low per capita
income
 Ex: Bangladesh, Mali, Ethiopia
© 2012 John Wiley & Sons, Inc. All rights reserved.
Types of Natural Resources
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Overpopulation

People overpopulation
 Too
many people in a given geographic area
 Problem in many developing nations

Consumption overpopulation
 Each
individual in a population consumes too
large a share of the resources
 Problem in many highly developed nations, US in
particular
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Consumption

Consumption
 Human
use of materials and energy
 People in HDCs are big consumers

Unsustainable Consumption
 Occurs
when the level of demand on a country’s
resources damages or depletes the resource
enough to reduce the quality of life for future
generations
 Caused by overpopulation and/or
overconsumption
© 2012 John Wiley & Sons, Inc. All rights reserved.
Ecological Footprint

The average amount of land, water and ocean
required to provide that person with all the
resources they consume
Earth’s Productive Land and Water
11.4 billion
hectares
1.8 hectares
Amount Each Person is Allotted (divide
Productive Land & Water by Human Pop.)
Current Global Ecological Footprint of each
person
2.7 hectares
© 2012 John Wiley & Sons, Inc. All rights reserved.
Ecological Footprint

Humans have an ecological overshoot
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Ecological Footprint
Comparison
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IPAT Model

Measures 3 factors that affect environmental
impact (I)
Environmental
Impact
Affluence per
person
I=P A
T
Number
of people
Environmental
effect of
technologies
© 2012 John Wiley & Sons, Inc. All rights reserved.
Questions of the day:

What was your
ecological footprint?

What are
commons?

Why do you think it
was high or low?

What point is Hardin
trying to get across
with his piece?

What factors may
have significantly
affected your
number?

What
topics/concepts is
this related to in
ES?
© 2012 John Wiley & Sons, Inc. All rights reserved.
Environmental Sustainability
© 2012 John Wiley & Sons, Inc. All rights reserved.
Environmental Sustainability


The ability to meet current human need for
natural resources without compromising the
needs of future generations
Requires
understanding:
The effects of our
actions on the earth
 That earth’s
resources are not
infinite

© 2012 John Wiley & Sons, Inc. All rights reserved.
Tragedy of the
Commons


Garrett Hardin (1915–2003)
Solving Environmental Problems is result of
struggle between:
 Short
term welfare
 Long term environmental stability and societal
welfare


Common pool resources
Garrett used Common Pastureland in medieval
Europe to illustrate the struggle
© 2012 John Wiley & Sons, Inc. All rights reserved.
Sustainable DevelopmentSystems Concept

Economic development that meets the needs of
the present generation without compromising
future generations
© 2012 John Wiley & Sons, Inc. All rights reserved.
Environmental Science

An interdisciplinary study of human
relationship with other organisms and the
earth
 Biology
 Physics
 Ecology
 Economics
 Geography
 Sociology
 Chemistry
 Demography
 Geology
 Politics
© 2012 John Wiley & Sons, Inc. All rights reserved.
Earth System and
Environmental Science

System
A
set of components that interact and function as
a whole

Global Earth Systems
 Climate,

atmosphere, land, coastal zones, ocean
Ecosystem
A
natural system consisting of a community of
organisms and its physical environment
© 2012 John Wiley & Sons, Inc. All rights reserved.
Earth Systems and
Environmental Science

Negative feedback
 Change
triggers a
response that
counteracts the
changed condition
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Feedback

Positive feedback
 Change
triggers a
response that
intensifies the
changing condition
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Scientific Method
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Controls and Variables in Experiment

Variable
A
factor that influences a process
 The variable may be altered in an experiment to
see its effect on the outcome

Control
 The
variable is not altered
 Allows for comparison between the altered
variable test and the unaltered variable test
© 2012 John Wiley & Sons, Inc. All rights reserved.
Five Steps to Addressing An
Environmental Problem


Five steps are
idealistic
Case Study: Lake
Washington
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Assessing Environmental Problem
Case Study: Lake Washington


Large, freshwater pond
Suburban sprawl in 1940’s
 10
new sewage treatment
plants dumped effluent into
lake

Effect = excessive
cyanobacteria growth that
killed off fish and aquatic
life
© 2012 John Wiley & Sons, Inc. All rights reserved.
Assessing Environmental Problem
Case Study: Lake Washington

Scientific Assessment
 Aquatic
wildlife assessment done in 1933 was
compared to the 1950 assessment
 Hypothesized treated sewage was introducing
high nutrients causing growth of cyanobacteria

Risk Analysis
 After
analyzing many choices, chose new location
(freshwater) and greater treatment for sewage to
decrease nutrients in effluent
© 2012 John Wiley & Sons, Inc. All rights reserved.
Assessing Environmental Problem
Case Study: Lake Washington

Public Education/Involvement
 Educated

public on why changes were necessary
Political Action
 Difficult
to organize sewage disposal in so many
municipalities
 Changes were not made until 1963!

Evaluation
 Cyanobacteria
slowly decreased until 1975
(gone)
© 2012 John Wiley & Sons, Inc. All rights reserved.
Assessing Environmental Problem
Case Study: Lake Washington

Results
© 2012 John Wiley & Sons, Inc. All rights reserved.