Transcript Chemistry review notes

THE STUDY OF ENVIRONMENTAL SCIENCE
Ecosystem: a particular
location whose interacting
components include living
(biotic) and non living
(abiotic) components
Environmental Science study
of ecosystems (ecology)
Environmentalism social
movement that seeks to
protect the environment
WHAT IS A SUSTAINABLE SYSTEM?
 one
that survives over some specified time that attains
its full expected life span
 a sustainable society manages it’s economy and
population size without exceeding the planet’s ability to
absorb environmental insults, replenish its resources and
sustain life
EASTER ISLAND
Treeless volcanic island
2200 miles off the coast of Chili
Moai -Stone Statues that line the
perimeter of the island (250) 13 ft
high and 14 tons.
Easter Island Story
 First inhabitants arrived at Easter Island as
early as 318AD. Most believe they were
Polynesian, however, some think they arrived
from South America.
 Between 1400-1600, population was around
9,000.

THE EASTER ISLAND STORY
In 1772, the first European visitors arrived on
Easter Island. It was deserted! Barren!
 There were signs of deforestation, soil
depletion and erosion.
 Most archeologist believe the natives cleared
the trees for crop land. Planted crops stripped
nutrients from the
soil.
 Clear signs of cannibalism.

LIVING OFF EARTH’S CAPITAL
 Do
Not eat the goose that lays the golden egg
 If you have one million in the bank at 10% interest, you
earn $100,000 year. If you spend just $110,000 per year
you will be bankrupt in 18 years
 Natural cycles will provide for us if we do not destroy our
natural capital
Don’t
Eat me
POPULATION AND ECONOMIC GROWTH
Linear growth
vs.exponential growth


linear growth: quantity
increases by a fixed
amount. EX. 1,2,3,4
Exponential growth:
quantity increases by a
fixed % of the whole in a
given time. EX:
2,4,8,16,32
Fig. 1-2 p. 4
HUMAN POPULATION GROWTH


Population is growing
exponentially at a
worldwide rate of 1.2%.
In developing countries
it is 1.7%. In developed 10
9
countries it is .1%.
8
226,000 more people 7
per day
6
World total
world
Developing
countries
developing
5
4
Developed
countries
developed
3
2
1
1950
2000
2050
2100
Fig. 1.1, p. 2
Fig. 1-3 p. 5
16
15
?
14
13
12
11
10
9
8
?
7
6
Billions of people
?
5
4
3
2
Black Death–the Plague
2-5 million 8000
years
Hunting and
gathering
6000
4000
2000
Time
Agricultural revolution
1
2000
B.C.
0
2100
A.D.
Industrial
revolution
Fig. 1.1, p. 2
RULE OF 70
70
% growth rate
doubling
time in years
World Population Growth Rate
70
1.35 %
51.8
years
ECONOMIC GROWTH


An increase in the capacity to provide goods and
services for people’s final use
economic growth is measured by an increase in GNP.





GNP: gross national product: $ value of goods and services
produced by a country’s businesses within and outside the
country
GDP: gross domestic product: $ value of goods and services
produced within the country
GWP: gross world product: total $ value of goods and services
produced in the world
The problem with GNP is the higher the GNP the more
resource depletion and environmental damage. GNP is not
the best indicator of quality of life.
per capita GNP: individuals slice of the economic pie
ECONOMIC DEVELOPMENT

countries are classified as
either developing or
developed based on their per
capita GNP and their level of
industrialization

developed countries: U.S.,
Canada, Japan, Australia,
New Zealand, and all of
Europe.

per capita GNP greater
than $10,000

generate 75% of
pollution

use 88% of resources

have 85% of wealth

make up 20% of
population
DEVELOPING: AFRICA, ASIA, LATIN
AMERICA





80% of population
some are middle income $1,000 to $10,000
per capita GNP
like South Africa, Mexico, Brazil, Malaysia
some are low income with a per capita GNP of
less than 1,000 like India, Pakistan, China
95% of population growth will take place in
developing countries
ENVIRONMENTALLY SUSTAINABLE
DEVELOPMENT


economic growth has
allowed us to
 Live longer
 be healthier
 have more comfort
It has not allowed us to
 stop environmental
problems
 Wipe out poverty
ENVIRONMENTALLY SUSTAINABLE
DEVELOPMENT:



encourages sustainable forms of economic growth
that meets the basic needs of the current
generations of humans without preventing future
generations and other species from meeting their
basic needs
discourages environmentally harmful and
unsustainable forms of economic growth
it requires that governments, businesses and
individuals integrate environmental goals into their
decision making process
THE WEALTH GAP



the gap between per
capita GNP or the rich
and poor has greatly
widened since 1980.
20% high income, 25%
moderate income, 30%
low income $2-3 / day,
25% very low income of
less than $1.00/day.
1 in 5 is hungry,
malnourished, lacks
access to clean water,
decent housing and
health care.
GLOBALIZATION


Globalization is the broad process of global, social,
economic and environmental change that leads to an
increasingly integrated world.
A few indicators of globalization:

global economy grew from 6.7 trillion to $42 trillion since
1950
WHAT IS A RESOURCE



anything that we get from the environment to
meet our needs and desires
perpetual resource: something that is continually
renewed like solar energy
renewable: On a human time scale something
that can be renewed fairly rapidly (Within
decades)
RENEWABLE RESOURCES
BIODIVERSITY

biodiversity: variety of life forms that can
survive a variety of conditions
 Genetic diversity
 species diversity
 ecological diversity
 provides free recycling, purification,
resources and pest control
SUSTAINABLE YIELD



renewable resources can be depleted
SUSTAINABLE YIELD: highest rate at which a
renewable resource can be used without reducing its
available supply
Tragedy of The Commons by “Garrett Hardin”:
Overuse of common property resources, which are
owned by no one but available to everyone free of
charge. For example clean air, oceans, fish, Antarctica.
This leads to exploitation then no one can use the
resource. “ If I don’t use this resource then someone
else will, the little bit I pollute is not enough to matter”
Resources
Perpetual
Direct
solar
energy
Nonrenewable
Winds,
tides,
flowing
water
Fossil
fuels
Metallic
minerals
Nonmetallic
minerals
(iron,
copper,
aluminum)
(clay,
sand,
phosphates)
Renewable
Fresh
air
Fresh
water
Fertile
soil
Plants and
animals
(biodiversity)
Fig. 1.11, p. 11
ENVIRONMENTAL DEGRADATION: OCCURS WHEN THE
RESOURCE’S NATURAL REPLACEMENT RATE IS EXCEEDED.
THE FOLLOWING ARE EXAMPLES OF DEGRADATION
- deforestation
 water
logging or
salinization of soil
 deforestation
 pollution
 reduction in
biodiversity
 groundwater
depletion
 Wetlands
destruction
NON-RENEWABLE: RESOURCES THAT EXIST IN
FIXED QUANTITIES IN THE EARTH’S CRUST



energy resources
like coal, gas,
uranium which are
burned and lost
metallic mineral
resources that can
recycled
Non-metallic
mineral resources
that are difficult to
recycle
WHAT IS POLLUTION

Any addition to air, water, soil, or food that
threatens the health, survival, or activities of
humans or other animals. It can be natural or from
humans
Two types of pollutant sources:


point source: where pollutants come from a single identifiable
source, like a drainpipe or a smokestack.
Non-point source: pollutants that come from dispersed sources.
Examples are runoff from fertilizers and pesticides or oil from
cars.
Two approaches to dealing with pollution:


pollution prevention
pollution clean-up
KEY ENVIRONMENTAL PROBLEMS AND
THEIR ROOT CAUSES







rapid population growth
rapid and wasteful use of resources with little emphasis
on pollution prevention
degradation of life support systems
poverty
failure of economic and political systems to have market
prices that include environmental costs
Our urge to dominate and manage nature for our use
with far too little knowledge of how nature works
Population x Affluence x Technology = Environmental
Impact
•
•
•
•
•
•
•
Air Pollution
Global climate change
Stratospheric ozone
depletion
Urban air pollution
Acid deposition
Outdoor pollutants
Indoor pollutants
Noise
•
•
•
•
•
•
•
•
Water Pollution
Sediment
Nutrient overload
Toxic chemicals
Infectious agents
Oxygen depletion
Pesticides
Oil spills
Excess heat
Biodiversity Depletion
• Habitat destruction
• Habitat degradation
• Extinction
•
•
Major
Environmental
Problems
Waste Production
• Solid waste
• Hazardous waste
•
•
•
•
•
•
•
•
•
•
Food Supply Problems
Overgrazing
Farmland loss
and degradation
Wetlands loss
and degradation
Overfishing
Coastal pollution
Soil erosion
Soil salinization
Soil waterlogging
Water shortages
Groundwater depletion
Loss of biodiversity
Poor nutrition
Fig. 1.13, p. 14
Per Captia Ecological Footprint
(Hectares of land per person)
Country
10.9
United States
5.9
The Netherlands
India
1.0
Fig. 1.10a, p. 11
Country
Total Ecological Footprint
(Hectares)
3 billion
hectares
United States
The Netherlands
India
94 million hectares
1 billion
hectares
Fig. 1.10b, p. 11
Developing Countries
X
X
Population (P)
X
X
Consumption
per person
(affluence, A)
=
Technological impact per
unit of consumption (T)
X
X
=
Environmental
impact of population (I)
=
Developed Countries
Fig. 1.15, p. 15
ENVIRONMENTAL WORLDVIEWS



Who should we believe?
The precautionary principle
Try not to be overwhelmed by the environmental
bad news because there is a lot of good
environmental news.
“Never doubt that a small group of
thoughtful, committed citizens cannot
change the world. Indeed, it is the only
thing that ever has”
Margaret Mead
PART 2: THE HISTORY OF ENVIRONMENTAL
SCIENCE
The Invention that changed everything:
 The plow

EFFECTS OF AGRICULTURAL REVOLUTION
Birth rates rose faster than death rates and
population increased
 People cleared increasingly larger plots of land
and destroyed more natural habitat
 People began accumulating material goods

INDUSTRIAL REVOLUTION





Began in England in the mid 1700s
Began when England used up all of its forests and
substituted coal for wood
Shift from renewable to n on-renewable
This lead to growth in mechanization and factory
towns
Fossil fuel powered farm equipment lead to an
increased agricultural yield which lead to more people
ENVIRONMENTAL IMPACTS
Reduced infant mortality
 Raised life expectancy which lead to more
people
 Better health
 Birth control
 Education
 Affordable goods
 income

GLOBALIZATION AND THE
INFORMATION REVOLUTION


Cultural shift to new
technologies such as
TV, computers an
internet
Hard to know what the
impacts will be
POSSIBLE IMPACTS





Help us understand more about the Earth and how
systems work
Allow us to respond to problems faster
Use technology to monitor changes in the Earth
More sophisticated technology to model complex
systems
Technology to reduce pollution and use materials
more effectively
BAD STUFF ABOUT IT



Cause confusion,
distraction, and a sense of
hopelessness because of
information overload
Increase environmental
degradation and
homogenization of world
cultures
We are developing new
technologies before we can
evaluate their impact
CONSERVATIONISTS
1870-1930



1870-1900: environmental concern grows because of
yellow fever, typhoid fever, cholera, garbage, air
pollution, unsafe factories, contaminated water
1891 Forest Reserve Act: established the
responsibilty of the federal government to protec
public lands
1892: John Muir formed the Sierra club
Fig. 2.6, p. 31
1901-1907: GOLDEN ERA OF
CONSERVATION







Theodore Roosevelt was president
He persuaded congress to give the president the power to
designate public land as wildlife refuges
Roosevelt Established the bureau of reclamation
He tripled the size of forest reserves
1905: Congress created the US Forest service to manage and
protect forest reserves. Gifford Pinchot was the first chief
1912: US National Park System was created by Congress
The passenger pigeon became extinct
Fig. 2.7, p. 31
Fig. 2.4, p. 30
HETCH-HETCHY DECISION: DIVIDED THE
CONSERVATIONISTS INTO TWO GROUPS.



Preservationists
Believed humans
should protect nature,
not conquer it
John Muir




Wise Use
Believed resources
should be used wisely to
enhance the nation’s
economic growth
Gifford Pinchot
Theodore Roosevelt
 Both
groups opposed delivering
public lands into the hands of a few
for profit
 Both would be disappointed by
what has happened over the years
1930-1960






The 1930s was the great depression and Franklin
Roosevelt was president
Aldo Leopold became the leading professional in
charge of wildlife management. Set up management
plans for the Grand Canyon. Others followed his
design
Low cost purchase of large tracts of land from cash
poor landowners
Started Civilian Conservation Corp
Built large dams to get cheap water to CA
Enacted the Soil Conservation Act of 1935 that was
CCC
Hoover Dam
THE 1960S

Rachel Carson published Silent Spring, which
documented how DDT was killing wildlife. The
beginning of the environmental Era.
THE 1960S
1964 Wilderness Act allowed the government
to protect large tracts of public land as part of
the National Wilderness System
 1965-1970 science of ecology was created to
understand earth
 Cuyahoga River caught fire and burned for
eight days

1960S




Massive air pollution in New
York leaves 300 dead
Lake Erie beaches closed
due to pollution
Santa Barbara coastline
heavily polluted by leaking
offshore oil rigs.
Foam in rivers from
pollution
THE 1970S
April 20th first Earth Day
 1970 Richard Nixon created EPA (the
Environmental Protection Agency
 1973 OPEC oil embargo
 1974 CFCs found to be creating ozone hole
 1978 Love Canal
 1979 Three Mile Island

1980S

The Wise Use movement was formed which
was an industrial coalition aimed at destroying
all the environmental laws
PART 3 SCIENCE, ENVIRONMENTAL SCIENCE, AND
CRITICAL THINKING
Goal of Science – creation of a new idea, principle,
or model that connects and explains facts and
leads to usable predictions about what is likely to
happen in nature.
 Scientific Method – Observe > Hypothesize > Argue
> Test > Hypothesize > Argue > Test
 Scientific Theory – an idea or principle, or model
that ties together and explains multiple facts that
previously appeared not to be related and is
supported by a great deal of evidence. (natural
selection)
 Scientific or Natural Law – a description of what
happens in nature time after time in the same way
without known exception. (second law of
thermodynamics)
*
III. SCIENTIFIC METHODS

Steps
1. Pose a question
2. Gather info (knowns)
3. What new info/data needs to be gathered?
4. Develop a hypothesis that explains data and
predicts new facts. Could there be other
explanations?
5. Develop an experiment that can be done to test the
hypothesis so it can become a scientific theory.
SINGLE VARIABLE ANALYSIS

1. Set up two groups
a. Experimental group – chosen variable is
changed in some way.
b. Control group – chosen variable is not changed.

This type of experiment is designed so that all
conditions are the same except for the single
variable in the experimental group. This is to be
sure that the variable is the only factor that could
possibly cause any observed change.
DOUBLE BLIND EXPERIMENT (USED TO TEST MOST NEW
DRUGS)
2. Set up two groups
a. Experimental group – one group of patients is given a new
drug.
b. Control Group – similar group of patients is given a
placebo (sugar pill).

This is called a double blind experiment because neither the
patient or the doctor is aware of who is receiving the drug or
the placebo. This is done to avoid biased results.

Multivariable Analysis – Many of the questions investigated by
environmental scientists involve a huge number of interacting
variables (synergism). In multivariable analyses
mathematical models run on high-speed computers are used
to analyze the interaction of many variables.
V. SCIENCE RESULTS (CAN DO 2 THINGS)
1)
Disprove
2)
Establish that a model, theory or law has an
extremely high probability of being true.
Nothing can every be proven. Everything we know
is just theory. Science is dynamic and
changing.
VI. FRONTIER SCIENCE VS. CONSENSUS
SCIENCE

Frontier Science –
“breakthroughs” these are
preliminary results that are
often controversial because
they have not yet been widely
tested and accepted.

Consensus Science - consist of
data, theories and laws that are
widely accepted within the
scientific community because
they have been tested and
retested or because
observations of nature support
them.
VII. LIMITATIONS OF ENVIRONMENTAL SCIENCE
1. Validity of Data – Difficulty of Accurate
Measurement (soil erosion, species
extinction, forest loss)
2. Multiple Variables - not enough info,
difficult to analyze data
FEEDBACK LOOPS

Positive Feedback Loop – reinforces itself, a change in a system, which
causes the system to make another change in the same direction
(vicious circle). Positive feedback systems destabilize a system.
(Easter Island)

Negative Feedback Loop - a change in a system which results in a
change in the opposite direction. Negative feedback loops lead to
dynamic equilibrium and homeostasis within a system. (Body Temp)
Rate of metabolic
chemical reactions
Positive feedback loop
Heat in body
Heat input
from sun and
metabolism
Blood
temperature in
hypothalamus
Excess temperature
perceived by brain
Sweat production
by skin
Heat loss
from air
cooling skin
Negative feedback loop
Fig. 3.4, p. 51
SYNERGY

Synergistic Interaction two or more processes
interact so that the
combined effect is
greater that the sum of
the two parts.

Environmental Scientists
attempt to identify both
harmful and beneficial
synergisms so that we
can:
1. counter harmful ones
2. promote beneficial ones