Science and the Environment
Understanding the Environment
The environment is everything around us.
◦ Man made things
◦ Complex relationships that connect the world
Understanding the Environment cont.
Environmental Science is multidisciplinary.
◦ Involves many fields of study.
Social sciences (economics, law, politics, etc).
Scientists and Citizens
Many times, the science studied by
professionals are the findings of everyday
◦ Three legged frogs of lakes in Minnesota were
first discovered by middle school students.
Our Environment through time
Environmental change is not a modern
◦ Wherever humans hunt, grow food, settle,
environmental change occurs.
This is a painting of what
Manhattan probably looked
like 300 hundred years ago
(A ‘blink’ in human history)
Our Environment through time
For most of human history, people were
◦ Small groups, migrated. Even today, they still exist
in remote parts of the world.
group in New Guinea,
island off the coast of
What are some ways that hunter-
gatherers have impacted their
•Hunting bison and other grazers
•May have lead to the disappearance
of larger mammals.
•Helped to spread plants to areas where
the plants didn’t exist.
•Set fires to prevent tree growth.
Following the hunter-gatherer period.
Collected seeds, domesticated animals.
People stopped migrating and built farms.
Population started to grow at an
Grasslands, forests, and wetlands were
replaced with farmland.
◦ Destroyed natural habitats.
Mid 1700’s the use of human and animal muscle
and water power changed over to use of fossil
fuels (coal, oil and natural gas).
◦ Greatly increased the efficiency of agriculture,
industry, and transportation.
◦ Increased sanitation, nutrition and medical care.
◦ Populations grew
◦ Pollution increased
◦ Habitat loss increased
In the 1900’s modern societies increased their
use of artificial substances (plastics, fertilizers,
Earth is a closed system
Earth has a limited amount of resources.
◦ The only things that enter Earth’s atmosphere
in large amounts are energy and the only
thing to leave in large amounts is heat.
◦ Environmental problems
can occur on different
Local, regional, or global.
The Agricultural and Industrial Revolutions
Both allowed the human population to
grow at a much faster rate then ever
Development of modern medicine and
sanitation systems perpetuated the
problem of population growth.
Before 1700 population stayed relatively
constant. After 1700 human population
grew at an exponential rate.
Human Population Growth
What are our main Environmental Problems?
◦ Renewable vs. nonrenewable resources.
When does a resource switch from being renewable to non?
◦ What types are there?
Biodegradable Pollutants- can be
broken down by natural processes.
Ex: Sewage and newspaper
Nondegradable Pollutants- such
as mercury, lead, some plastics
Loss of biodiversity
◦ Number and variety of species.
◦ Where is the most/least
biodiversity found on Earth?
Tragedy of the Commons
Discovered by Hardin
◦ He found that when animals were left to
graze on common land, people tended to
graze as many as possible which degraded
◦ He also found the opposite to be true: When
common land was fenced off to individual
owners, they only grazed as many animals as
the land could support.
How do we share common goods?
Hardin did not consider the point that
humans are social beings.
◦ Together, we can plan, organize, consider
scientific evidence, and propose solutions.
What ever the solution, may override the
needs of the individual, but will improve
the environment for everyone in the long
Supply and demand:
◦ The greater the demand for a limited supply of
something the more that something is worth.
What are some examples of supply and demand in today’s
◦ Balances the cost of an action against the benefits one
expects from it.
◦ Depending upon who is evaluating the risk, the results
may be different.
Public views risk of nuclear power differently than the
Developed vs. Developing
Higher average Lower average
Slower population Simple and
growth agriculturally based
Diverse industrial incomes
economies Rapid population
Stronger social growth
support systems Parts of Africa, India,
US, Japan, countries middle East…
of Western Europe…
Population and Consumption
Two root problems:
◦ Human population in some areas is growing too
quickly for the local environment to support it.
◦ People are using up, wasting, or polluting many
natural resources faster than they can be
One way to express the differences in
consumption between nations is an Ecological
◦ Calculation of the amount of land and resources
needed to support one person from a particular
Sustainability and Stewardship
Sustainability: human needs are met in
such a way that a human population can
Stewardship: The careful and responsible
management of something entrusted to
one’s care (usually not at their own