Fixing a Hole in the Sky
• Ozone is a naturally occurring molecule that absorbs
and redirects harmful UV radiation.
• In the 1970s, Mario Molina and Sherwood Rowland
discovered that CFCs were rapidly destroying ozone
in the stratosphere.
• Today, most nations have banned CFCs, and the
ozone hole is expected to close up around 2050.
Talk About It Should environmental scientists’
discoveries about the natural world influence human
activity? If so, how?
Chapter 1: Our Island, Earth
What Is Environmental Science?
• The study of our planet’s
natural systems and how
humans and the environment
affect one another
• The environment includes all
living and nonliving things with
which organisms interact.
National Marine Fisheries Service scientists studying
whether commercial boats are harming endangered
killer whales
• Understanding the interactions
between humans and the
environment is the first step to
solving environmental
problems.
Chapter 1: Our Island, Earth
Natural Resources
• Natural resources are materials and energy sources found in nature that
humans need to survive.
– Renewable resources: Naturally replenished over short periods
– Nonrenewable resources: Naturally formed more slowly than we use them.
– Renewable resources can become nonrenewable if used faster than they are
replenished.
Cleaning the Tides of
San Diego and Tijuana
• The heavily polluted Tijuana River crosses over from Mexico to the U.S.
and empties into the Pacific Ocean near San Diego, California, forcing
frequent beach closures.
• Pollution sources include U.S.-owned factories as well as Mexican farms,
homes, and sewage treatment plants.
• In 1990 the U.S. and Mexico agreed to build a wastewater treatment
plant, but construction has yet to be completed.
Talk About It Why is the pollution problem in the Tijuana
River particularly difficult to solve? How does this case
illustrate the connections between the environment, the
economy, and government policy?
Chapter 2: Economics
Consumer and Corporate
Responses
• Changing consumer values can
drive corporations to pursue
sustainability.
• Ecolabeling is an example of a
corporate response to the call for
sustainable goods and services.
Did You Know? Organic farming is one of the
fastest-growing segments of U.S. agriculture. Land
devoted to growing organic has expanded by about
15% each year since 2002.
Chapter 2: International Environmental Policy and Approaches
International Environmental Policy
• Environmental issues often involve
more than one nation.
• International organizations
promote cooperation between
nations:
•
•
•
•
The United Nations
The European Union
The World Trade Organization
The World Bank
The Gulf of Mexico’s
Dead Zone
• Nutrient-rich runoff causes plankton blooms and
hypoxia—low oxygen levels—in the Gulf of Mexico.
• Hypoxia kills or displaces marine organisms, causing
a decline in the fisheries and the fishing industry.
• U.S. government and farmers debate the need to cut
down on fertilizer use.
Talk About It Do you think the distance between the source of
the nitrogen and phosphorus and the dead zones themselves
makes it difficult to manage this problem? Why or why not?
Chapter 3: Earth’s Spheres
Tectonic Plates
• There are three major types of plate boundary:
– Divergent
– Transform
– Convergent
Chapter 3: Earth’s Spheres
Divergent and Transform Plate
Boundaries
• Divergent boundaries:
Rising magma pushes
plates apart.
Divergent plate boundary
• Transform
boundaries: Plates slip
and grind alongside
one another.
Transform plate boundary
Chapter 3: Earth’s Spheres
Convergent Plate Boundaries
• Plates collide, causing one of two things to happen:
– Subduction: One plate slides beneath another.
– Mountain-building: Both plates are uplifted.
Chapter 3: Earth’s Spheres
The Hydrosphere
• Consists of Earth’s water
• Most of Earth’s water
(97.5%) is salt water.
Greenlaw Brook, Limestone, Maine
• Only 0.5% of Earth’s
water is unfrozen fresh
water usable for
drinking or irrigation.
• Earth’s available fresh
water includes surface
water and ground water.
Did You Know? If it is depleted, groundwater
can take hundreds or even thousands of years
to recharge completely.
Chapter 3: Earth’s Spheres
The Water Cycle
Finding Gold in a Costa Rican Cloud
Forest
• Golden toads lived in Costa Rica’s
Monteverde cloud forest.
• Golden toads were first described in 1964.
They were extinct by 1989.
Talk About It Why is the extinction of the golden
toad a global concern?
Chapter 4: Studying Ecology
Biotic and Abiotic Factors
• Biotic factors: Parts of an
ecosystem that are living or
used to be living
• Abiotic factors: Parts of an
ecosystem that have never
been living
Did You Know? Decaying organisms
are biotic factors as long as their
structure remains cellular.
Chapter 4: Studying Ecology
Habitat
• The specific environment in which an organism lives
• Habitats provide an organism with resources—
anything an organism needs to survive and
reproduce, including food, shelter, and mates.
Chapter 4: Describing Populations
Population Distribution
• How organisms are arranged within an area:
• Random distribution:
Organisms arranged in
no particular pattern
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are needed to see this picture.
• Uniform distribution:
Organisms evenly spaced
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• Clumped distribution:
Organisms grouped near resources;
most common distribution in nature
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