introducing environmental science and sustainability chapter 1 what are these? how do they relate to...
TRANSCRIPT
Introducing Environmental Science and
Sustainability
Chapter 1
What are these? How do they relate to issues of globalization
and sustainability?
Human Impacts on the Environment
Increasing Human Numbers
What does this picture show?
Human Impacts on the Environment
Most populous countries:
1) China 1,374,853,000
2) India 1,155,011,000
3) United States 309,163,000
4) Indonesia 258,825,000
5) Brazil 195,580,000
Source: US Census Bureau, Global Population Profile: 2002
What is a Highly Developed Country? A Moderately Developed Country?
A Less Developed Country?
In what types of
countries is most of the growth occurring?
Of the 400 cities with a population
of at least 1 million, 234 are in
developing
countries.
Human Impacts on the Environment
At what type of
rate is the population growing?
How Fast Is the Human Population Growing?
At an exponential rate! Human death rates have dropped because of an increase in
food supplies and better health and sanitation. Doubling Time - A measure of population growth where the
number of years it takes for a population growing at a specified rate to double its size.
To calculate “Doubling Time,” use the Rule of 70.
€
DoublingTime =70
%GrowthRate
Human Impacts on the Environment
Poverty :
• per capita income of less than $1 a day
• 1.2 billion worldwide currently live at this level
Leads to . . . Inadequate health care
Unsanitary water
Poor nutrition
Lower life expectancy
Relationship Betwen Population Growth, Use of Natural Resources, and Environmental Degradation
1) The resources essential to survival are small, but individuals in developing countries deplete these resources because of their increasing population.
2) In developed nations, resource demands are large (extravagent consumers), and resources are exhausted.
What is a Resource?Resource -- Anything obtained from the environment to
meet human needs and wants.Renewable Resource - Can be replenished rapidly
through natural processes as long as it is not used up faster than it is replaced– Examples?– What is a resources sustainable yield?– When does “Environmental Degradation” occur?
Nonrenewable Resource - resources that exist in a fixed quantity or stock in the earth’s crust– Examples?
Population, Resources, and the Environment
Types of resources:
Renewable, but only when managed in a sustainable way
•What does sustainable mean?
•What is the sustainable yield of a resource?
Population, Resources, and the Environment
Resource Consumption:
• Because of our greater consumption rates, 1 US child has the environmental impact of 12+ children in less developed countries.
Population, Resources, and the Environment
•People Overpopulation: when excess # of people cause environmental damage.
•Consumption Overpopulation: when people consume enormous amounts of natural resources.
What is the difference between people overpopulation and consumption
overpopulation?
Population, Resources, and the Environment
Ecological footprint Ecological Footprint -- the amount of land
needed to produce the resources needed by an
average person in a country.
Population, Resources, and the Environment
IPAT Model
I = P A T
Environmental Impact
Number of people
Affluence per person
Environmental effect of
technologies
Why is this a good model? Why is this NOT a good
model?
Environmental Sustainability
Sustainability and the Tragedy of the
Commons
Garrett Hardin What is the Tragedy of the Commons?
Environmental Science
The Process of ScienceProblem recognition or
question
Hypothesis development
Experimentation
Analysis
Share knowledge
Make predictions
Hypothesis supported? YESNO
Other scientistsNew knowledge
Environmental Science
Controls and Variables in Experimental Design
Variable:
Control group :• examined variable is left unaltered
•factors influencing processes being examined.•hypothesis examines ONE variable, holding others constant. This one variable is called the independent variable. What this change affects is the dependent variable.
Environmental Science
Inductive and Deductive Reasoning• Inductive - examines a series of facts for
commonalities that can be concluded.• Example:
– Fact: an ant has six legs– Fact: a wasp has six legs– Fact: a beetle has six legs– Conclusion: all insects have six legs
• Deductive - examines for relationships among data moving from generalities to specifics.
• Example:– General rule: all insects have six legs– Specific example: a grasshopper is an insect– Therefore: a grasshopper has six legs
Addressing Environmental Problems
Scientific Assessment
Risk Analysis
Public education and involvement
Political action
Evaluation
Addressing Environmental Problems
Case in Point: Lake Washington
•Scientific assessment
•Public education and involvement
•Political action
Addressing Environmental Problems
Case in Point: Lake Washington
Evaluation
Addressing Environmental Problems
Case in Point: Lake Washington
Evaluation