Introducing Environmental Science and Sustainability

Introducing Introducing EnvironmentaEnvironmental Science and l Science and SustainabilitySustainability

Chapter 1

Overview of Chapter 1Overview of Chapter 1

o Human Impacts on The EnvironmentHuman Impacts on The Environmento Population, Resources and the Population, Resources and the

EnvironmentEnvironmento Environmental SustainabilityEnvironmental Sustainabilityo Environmental ScienceEnvironmental Scienceo Assessing Environmental ProblemsAssessing Environmental Problems

The Environment (Earth)The Environment (Earth)

Life has existed on earth for 3.8 billion Life has existed on earth for 3.8 billion yearsyearsEarth well suited for lifeEarth well suited for life

• Water covers ¾ of planetWater covers ¾ of planet• Habitable temperatureHabitable temperature• Moderate sunlightModerate sunlight• Atmosphere provides oxygen and carbon Atmosphere provides oxygen and carbon

dioxidedioxide• Soil provides essential minerals for plantsSoil provides essential minerals for plants

But humans are altering the planet; not But humans are altering the planet; not always in positive waysalways in positive ways

Human Impacts on the Human Impacts on the EnvironmentEnvironment

Increasing Increasing Human Human NumbersNumbers


Most populous countries:Most populous countries:

1) China1) China 1,343,239,9231,343,239,923

2) India2) India 1,205,073,6121,205,073,612

3) United States3) United States 313,847,465313,847,465

4) Indonesia4) Indonesia 248,645,008248,645,008

5) Brazil5) Brazil 199,321,413199,321,413

Source: CIA.gov, Global Population Profile: 2012 estimates

PUT A CLOCK ON IT!PUT A CLOCK ON IT!o SHOW CLOCK

Human Human Impacts on Impacts on

the the EnvironmentEnvironment

PopulationPopulation

Globally, 1 in 4 people Globally, 1 in 4 people lives in extreme lives in extreme poverty poverty

Difficult to meet Difficult to meet population needs population needs without exploiting without exploiting earth’s resourcesearth’s resources


Poverty :Poverty :• per capita income of less than $1 a per capita income of less than $1 a dayday• 1.2 billion worldwide currently live at 1.2 billion worldwide currently live at

this levelthis levelLeads to . . .

Inadequate health care

Unsanitary water

Poor nutrition

Lower life expectancy

Population, Resources, and the Population, Resources, and the EnvironmentEnvironment

The contrast between less developed and The contrast between less developed and highly developed countries is great:highly developed countries is great:

Gap Between Rich and PoorGap Between Rich and Poor

Highly Developed Countries (HDC)Highly Developed Countries (HDC)• Complex industrialized bases, low Complex industrialized bases, low

population growth, high per capita incomespopulation growth, high per capita incomes• Ex: US, Canada, JapanEx: US, Canada, Japan

Less Developed Countries (LDC)Less Developed Countries (LDC)• Low level of industrialization, very high Low level of industrialization, very high

fertility rate, high infant mortality rate, low fertility rate, high infant mortality rate, low per capita incomeper capita income

• Ex: Bangladesh, Mali, EthiopiaEx: Bangladesh, Mali, Ethiopia


Types of resources:Types of resources:

Renewable, but only when managed in a sustainable way


Resource Consumption:

• because of our greater consumption rates, 1 US child has the environmental impact of 12+ children in less developed countries.

OverpopulationOverpopulation

People overpopulationPeople overpopulation• Too many people in a given geographic Too many people in a given geographic

areaarea• Problem in many developing nationsProblem in many developing nations

Consumption overpopulationConsumption overpopulation• Each individual in a population consumes Each individual in a population consumes

too large a share of the resourcestoo large a share of the resources• Problem in many highly developed nationsProblem in many highly developed nations

Ecological FootprintEcological Footprint

The average amount of land, water and ocean The average amount of land, water and ocean required to provide that person with all the required to provide that person with all the resources they consumeresources they consume

Earth’s Productive Land and WaterEarth’s Productive Land and Water 11.4 billion 11.4 billion hectareshectares

Amount Each Person is Allotted Amount Each Person is Allotted (divide Productive Land and Water (divide Productive Land and Water by Human Population)by Human Population)

1.9 hectares1.9 hectares

Current Global Ecological Footprint Current Global Ecological Footprint of each personof each person

2.3 hectares2.3 hectares

Ecological Footprint ComparisonEcological Footprint Comparison


IPAT ModelIPAT Model

I = P A T

Environmental Impact

Number of people

Affluence per person

Environmental effect of technologies

Environmental SustainabilityEnvironmental Sustainability

Sustainability:Sustainability:

StewardshipStewardship

Environmental SustainabilityEnvironmental SustainabilityThe ability to meet current human need The ability to meet current human need for natural resources without for natural resources without compromising the needs of future compromising the needs of future generationsgenerations

Requires understanding:Requires understanding:• The effects of our actions on the earthThe effects of our actions on the earth• That earth’s resources are not infiniteThat earth’s resources are not infinite

Environmental SustainabilityEnvironmental Sustainability

Sustainability Sustainability

and the and the

Tragedy of the Tragedy of the Commons Commons

Garrett Hardin

Sustainable DevelopmentSustainable DevelopmentEconomic development that meets the Economic development that meets the needs of the present generation without needs of the present generation without compromising future generationscompromising future generations

Environmental ScienceEnvironmental Science

• Interdisciplinary study of the interconnected problems

associated with the environment.

• Heavily leans upon ecology.

Scientific MethodScientific Method

Environmental ScienceEnvironmental ScienceControls and Variables in

Experimental DesignVariable:

Control group :• examined variable is left unaltered

• factors influencing processes being examined.• hypothesis examines ONE variable, holding others constant.

This is the experimental group.


o HypothesisHypothesis: Burning will increase : Burning will increase frequency of prairie wildflowers.frequency of prairie wildflowers.

Which is the control group?

Earth As a SystemEarth As a System

SystemSystem• A set of components that interact and A set of components that interact and

function as a wholefunction as a whole

Global Earth SystemsGlobal Earth Systems• Climate, atmosphere, land, coastal zones, Climate, atmosphere, land, coastal zones,

oceanocean

EcosystemEcosystem• A natural system consisting of a community of A natural system consisting of a community of

organisms and its physical environmentorganisms and its physical environment

System approach to environmental scienceSystem approach to environmental science• Helps us understand how human activities Helps us understand how human activities

effect global environmental parameterseffect global environmental parameters

Earth SystemsEarth Systems

Most of earth’s systems are in dynamic Most of earth’s systems are in dynamic equilibrium or steady stateequilibrium or steady state

• Rate of change in one direction equals that Rate of change in one direction equals that in the otherin the other

FeedbackFeedback• Change in 1 part of system leads to change Change in 1 part of system leads to change

in anotherin another• Negative feedback- change triggers a Negative feedback- change triggers a

response that counteracts the changed response that counteracts the changed conditioncondition

• Positive feedback- change triggers a Positive feedback- change triggers a response that intensifies the changing response that intensifies the changing condition condition


How does the view of a How does the view of a TheoryTheory differ between scientists and the differ between scientists and the

public?public?

Controls and Variables in ExperimentControls and Variables in Experiment

VariableVariable• A factor that influences a processA factor that influences a process• The variable may be altered in an The variable may be altered in an

experiment to see its effect on the experiment to see its effect on the outcomeoutcome

ControlControl• The variable is not alteredThe variable is not altered• Allows for comparison between the altered Allows for comparison between the altered

variable test and the unaltered variable variable test and the unaltered variable testtest

Inductive and Deductive Inductive and Deductive ReasoningReasoning

Deductive ReasoningDeductive Reasoning• Proceeds from generalities to specificsProceeds from generalities to specifics• Adds nothing new to knowledge, but makes Adds nothing new to knowledge, but makes

relationships among data more apparentrelationships among data more apparent• Ex:Ex:

• GENERAL RULEGENERAL RULE: All birds have wings: All birds have wings• SPECIFIC EXAMPLESPECIFIC EXAMPLE: Robins are birds: Robins are birds• CONCLUSIONCONCLUSION (based on deductive reasoning): (based on deductive reasoning):

All Robins have wingsAll Robins have wings

Inductive and Deductive Inductive and Deductive ReasoningReasoning

Inductive ReasoningInductive Reasoning• Used to discover general principlesUsed to discover general principles• Seeks a unifying explanation for all the Seeks a unifying explanation for all the

data availabledata available• Ex:Ex:

• FACTFACT: Gold is a metal heavier than water: Gold is a metal heavier than water• FACTFACT: Iron is metal heavier than water: Iron is metal heavier than water• FACTFACT: Silver is a metal heavier than water: Silver is a metal heavier than water• CONCLUSIONCONCLUSION (based on inductive reasoning): All (based on inductive reasoning): All

metals are heavier than watermetals are heavier than water• Conclusions reached with inductive Conclusions reached with inductive

reasoning may changed with new reasoning may changed with new informationinformation

Five Stages to Five Stages to Addressing An Addressing An Environmental Environmental

ProblemProblemFive steps are Five steps are

idealisticidealistic• Real life is rarely so Real life is rarely so

neatneat

Following Slides are Following Slides are Case Study Using Case Study Using the Five Stagesthe Five Stages

Assessing Environmental ProblemAssessing Environmental ProblemCase Study: Lake WashingtonCase Study: Lake Washington

Large, freshwater pondLarge, freshwater pond

Suburban sprawl in 1940’sSuburban sprawl in 1940’s• 10 new sewage treatment 10 new sewage treatment

plants dumped effluent plants dumped effluent into lakeinto lake

Effect = excessive Effect = excessive cyanobacteria growth that cyanobacteria growth that killed off fish and aquatic killed off fish and aquatic lifelife


Scientific AssessmentScientific Assessment• Aquatic wildlife assessment done in 1933 Aquatic wildlife assessment done in 1933

was compared to the 1950 assessmentwas compared to the 1950 assessment• Hypothesized treated sewage was Hypothesized treated sewage was

introducing high nutrients causing growth introducing high nutrients causing growth of cyanobacteriaof cyanobacteria

Risk AnalysisRisk Analysis• After analyzing many choices, chose new After analyzing many choices, chose new

location (freshwater) and greater treatment location (freshwater) and greater treatment for sewage to decrease nutrients in effluentfor sewage to decrease nutrients in effluent


Public Education/InvolvementPublic Education/Involvement• Educated public on why changes were Educated public on why changes were

necessarynecessary

Political ActionPolitical Action• Difficult to organize sewage disposal in so Difficult to organize sewage disposal in so

many municipalitiesmany municipalities• Changes were not made until 1963!Changes were not made until 1963!

EvaluationEvaluation• Cyanobacteria slowly decreased until 1975 Cyanobacteria slowly decreased until 1975

(gone)(gone)

Addressing Environmental Addressing Environmental ProblemsProblems

Case in Point: Lake WashingtonCase in Point: Lake Washington

RESULTS

Addressing Environmental Addressing Environmental ProblemsProblems

Case in Point: Lake WashingtonCase in Point: Lake Washington

RESULTS

Documents

Introducing Environmental Science and Sustainability