Download Ch 13 Sec 3 Global Warming Note Taking Guide

Atmosphere and Climate
Change
Section 3: Global Warming
The Greenhouse Effect
• The Earth is similar to a _______________. The Earth’s
atmosphere acts like the glass in a _______________.
• Sunlight streams through the _______________and heats
the Earth. As this heat radiates up from Earth’s
_______________, some of it escapes into space. The rest of
the heat is absorbed by gases in the _______________and
warms the air.
• This process of heat _______________is called the
_______________ ____________.
The Greenhouse Effect
The Greenhouse Effect
• Not every gas in our _______________ absorbs heat
in this way.
• A _______________ is a gas composed of molecules
that absorb and radiate _______________radiation
from the sun.
• The major greenhouse gases are _______________,
_______________, CFCs, _______________, and
nitrous oxide. Of these, _______________and
_______________ account for most of the absorption
of that occurs in the atmosphere.
Measuring Carbon Dioxide in the Atmosphere
• In 1985, a _______________ named Charles Keeling installed
an instrument at the top of a tall tower on the volcano
_______________ in Hawaii. He wanted to precisely
measure the amount of _______________ in the air, far
away from forests and cities.
• In a forest, _______________ levels rise and fall with the
daily rhythms of _______________. Near cities, carbon
dioxide from traffic and industrial pollution raises the local
concentration of gas.
Measuring Carbon Dioxide in the Atmosphere
• The winds that blow steadily over _______________
have come thousands of miles across the Pacific
Ocean, far from most forests and human activities,
swirling and mixing as they traveled.
• _______________ reasoned that at Mauna Loa, the
average _______________ levels for the entire Earth
could be measured.
Measuring Carbon Dioxide in the Atmosphere
• Keeling’s first measurement, in March of 1958, was __________
percent, and the levels rose slightly the next month. By summer the
levels were falling, but in the winter, they rose again.
• During the summer, _______________ use more carbon dioxide for
photosynthesis than they release in respiration, causing the levels to
drop.
• In the winter, dying grasses and fallen leaves decay and ___________
the carbon that was stored in them, causing levels to rise.
Rising Carbon Dioxide Levels
• After a few years of _______________, it was obvious that
the levels were undergoing changes other than
_______________ fluctuations.
• Each year, the high carbon dioxide levels of winter were
_______________, and each year, the summer levels did not
fall as _______________.
• In 42 years, carbon dioxide has gone from 314 to 386 parts
per million, an increase of _______________ per million.
This increase may be due to the burning of ______________.
Rising Carbon Dioxide Levels
Greenhouse Gases and the Earth’s
Temperature
• Many scientists think that because greenhouse gases
trap heat near the Earth’s surface, more greenhouse
gases in the atmosphere will result in an __________
in global temperature.
• A comparison of carbon dioxide in the _____________
and average global temperatures for the past _______
years support that view.
Greenhouse Gases and the Earth’s
Temperature
• Today, we are releasing more _______________ than any
other greenhouse gas into the atmosphere.
• Millions of tons of carbon dioxide are released into the
atmosphere each year from _______________ that burn
coal or oil, and cars that burn _______________. Millions of
trees are _______________ in tropical rainforest to clear the
land for farming.
• We also release other greenhouse gases, such as CFCs,
_______________, and nitrous oxide, in significant amounts.
Greenhouse Gases
How Certain is Global Warming?
• _______________ is a gradual increase in the average
global temperature that is due to a higher
_______________ of gases such as _______________
in the atmosphere.
• Earth’s average global _______________ increased
during the 20th century and many scientists predict
that this _______________ trend will continue
throughout the 21st century.
How Certain is Global Warming
How Certain is Global Warming?
• However, not all scientists agree that the observed
_______________ is due to greenhouse gases.
• Some scientists believe that the warming is part of
natural _______________ _______________.
• They point out that widespread _______________ in
temperature have occurred throughout geological
time.
Modeling Global Warming
• Scientists are currently _______________ to make accurate
predictions about the _______________ of global warming
because climatic patterns are too complex and too many
variables must be taken into account to be solved, even
using today’s fastest computers.
• Predictions about climate change are based on ___________
_______________ that predict how phenomena such as
temperature, rainfall patterns, and _______________ will be
affected.
Modeling Global Warming
• Computer modeling is complicated by the Earth’s _________
_______________ that sometimes make it necessary to use
different equations under changing simulated ___________ .
• These feedback processes are related to things such as
clouds, ___________ , ice, changes in ___________ , and
changes in ___________ .
• Computer models are becoming more reliable as more data
are available, additional factors are considered, and faster
computers are built.
The Consequences of a Warmer Earth
• The ___________ of global warming could include a number
of potentially serious environmental problems.
• These problems range from the ___________ of global
weather patterns and a global rise in ___________ to
adverse impacts on ___________ , ___________ , and
animal and plant ___________ .
• Other impacts on the ___________ that could not be
predicted by computer models might also arise.
Melting Ice and Rising Sea Levels
• If the global temperature ___________ , the amount of ice
and snow at the poles would ___________ , causing sea
levels around the world to ___________ .
• Coastal ___________ , and other low-lying areas could be
___________ . People who live near coastlines could lose
their homes and sources of income.
• The ___________ of bays and estuaries might increase,
adversely affecting marine fisheries. Also, ___________
aquifers could become too salty to be used as sources of
fresh water.
Global Weather Patterns
• If the Earth warms up significantly, the ___________ of the
oceans will absorb more heat, which may make hurricanes
and ___________ more common.
• Some scientists are concerned that global warming will also
cause a change in ocean ___________ patterns, shutting off
the ___________ ___________ .
• Such a change could significantly affect the world’s weather.
Severe ___________ could occur in some regions at the
same time droughts devastate other regions.
Human Health Problems
• Greater numbers of heat related ___________ could occur.
Very young and very old people would have the greatest risk
of heat ___________ .
• Concentrations of ground level ___________ could increase
as air temperatures rise, causing ___________ illnesses,
especially in urban areas, to increase.
• Warmer temperatures might enable ___________ , which
carry diseases such as ___________ and ___________ , to
greatly increase in number.
Agriculture
• Agriculture would be most severely impacted by
global warming if extreme weather events, such as
___________ , became more frequent.
• Higher temperatures could result in ___________
crop ___________ .
• As a result, the demand for ___________ could
increase, which would further deplete ___________
that have already been ___________ .
Effects on Plants
• Climate change could alter the ___________ of plant
species and could change the ___________ of plant
communities.
• A warmer climate could cause trees to ___________
northward into cooler areas.
• ___________ could shrink in areas in the southern
part of their range and lose ___________ .
Effects on animals
• Global warming could cause a shift in the ___________
range of some animals. For example, Northern birds may not
migrate as far south during the winter.
• Warming of surface waters of the ocean might cause a
reduction of ___________ , tiny ___________ animals, that
many marine animals depend on for food.
• Warming tropical waters may kill ___________ that nourish
___________ , thus destroying coral ___________ .
Recent Findings
• The _________________ on Climate Change (IPCC) issued its
Third Assessment Report (TAR) in 2001 that described what
was currently known about the global ____________ system
and provided future ____________ about the state of the
global climate ____________ .
• The IPCC reported that the average global ____________
____________ increased by 0.6ºC during the 20th century,
snow and ice cover has ____________ , and the global sea
level has ____________ .
Recent Findings
• The IPCC also reported that concentrations of
____________ gases have continued to increase as a
result of human ____________ .
• It has also predicted that human ____________ will
continue to change the ____________ of the Earth’s
atmosphere and continue to ____________ the Earth
throughout the 21st century.
Reducing the Risk
• The ____________ ____________ is an international
treaty according to which developed countries that
signed the treaty agree to reduce their emissions of
carbon dioxide and other ____________ that may
contribute to global warming by the year 2012.
• In March of 2001, the United States decided not to
____________ the Kyoto Protocol. However, most
other developed nations are going ahead with the
treaty.
Reducing the Risk
• The need to slow global warming has been
____________ by the global community. Some
nations and organizations have engaged in
____________ projects to reduce carbon dioxide.
• However, the attempt to ____________ global
warming is made difficult by the ____________ ,
____________ , and ____________ factors faced by
different countries.
Reducing the Risk
• Conflict has already arisen between ____________
and ____________ countries over future CO2
emissions.
• Developing countries are projected to make up
____________ of all CO2 emissions by 2035.
Reducing the Risk