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American History Since 1865
and Climate Change:
Coincidence or
Connection ?
Robert T. Longo
Adjunct Professor of History
Northampton Community College
January 2014
•American History Since 1865 (sometimes known as “U.S. History II”) is a course
found in almost all high school and college programs. It covers a well-known script
that most Americans carry in their heads at least in general terms, if not the most
minute detail. It’s the story of the rise of the United States from the ashes of its Civil
War, its greatest challenge and its greatest disaster all rolled into one, to become one of
the greatest economic, military and political superpowers in the history of the planet.
The rise of big business, the extension of democracy, World War I, the consumer
economy of the 1920s, the Great Depression, World War II, the Civil Rights
Movement, the Cold War, the space program, the Vietnam War, rock’n roll, the
“counter-culture,” Watergate, “Reaganomics,” “Women’s Lib,” “Operation Desert
Storm,” inflation, “9/11,” the wars in Iraq and Afghanistan, and the “Great Recession of
2007,” are all part of this well-worn and stress-filled narrative.
•Increasingly, however, another part of our history, which had been conspicuously
absent from the course narrative, has been recently getting some attention. As has
happened throughout the long geological history of the planet, the climate has been
going through its own stress-filled changes at the same time that the U.S. has been on
the rise. Expanding scientific knowledge, supported by previously overlooked
historical evidence, tells us of fluctuating changes in the climate in the U.S. and around
the world in the past, and indications of changes going into the future that raise many
challenging problems and questions.
We’re Getting Used to Headlines Like
Extreme weather patterns may worsen in 2012 says
NASA scientist
Posted on February 26, 2011by The Extinction Protocol
February 26, 2011 – AUSTRALIA – As unusual as weather patterns have
been and will be in 2011; it’s hard to imagine things getting more
extreme but that’s exactly what top climate scientists are now warning
the public about. ’Kevin Trenberth, the head of climate analysis for of
the National Centre for Atmospheric Research, explained: “There is a
systematic influence on all of these weather events nowadays because
there is more water vapour lurking around in the atmosphere than there
used to be, say, 30 years ago. It’s about a four per cent extra amount,
provides plenty of moisture for these storms and it’s unfortunate that
the public is not associating this with the fact that this is one
manifestation of climate change. And the prospects are that these kinds
of things will only get worse in the future.” Globally, 2010 saw 19
nations – a record number – set temperature records including Pakistan,
which hit 53.5C, the hottest temperature ever reliably measured in
Asia’s history. From mid-December to mid-January of this year, the
National Centre for Atmospheric Research (NCAR) reported that parts of
north-eastern Canada were 21C above average, “which are very large
values to be sustained for an entire month.” In Coral Harbour, in the
north-west corner of Hudson Bay, “the town went 11 days without
getting down to its average daily high.” In mid-December, Greenland
experienced the most extreme high-pressure system of its kind ever
recorded anywhere on the planet. Last year saw the greatest ice melt on
record for Greenland. In America, Tennessee was devastated by a oncein-1,000-year rain storm leading to what some called Nashville’s Katrina.
In October, the strongest storm ever recorded in the Midwest broke
pressure records. Craig Fugate, who heads the US Federal Emergency
Management Agency, said in December: “The term ‘100-year event’
really lost its meaning this year.”……………..
The above article appeared on the Internet in early 2011, predicting an
increase in extreme weather in 2012. Did this prediction come true? 2012
did, in fact, experience numerous examples of extreme weather, culminating
in Hurricane Sandy (also known as Superstorm Sandy), the combination of a
tropical hurricane combining with a “Noreaster” storm along the east coast of
North America that produced the lowest barometric pressure reading on
record. It deviated from typical hurricanes by veering left as it reached the
coast of New Jersey and New York City, causing the largest storm surge on
record for that area and devastating the Jersey shore, Staten Island, waterfront
areas in Brooklyn and Queens, and flooding major areas of Lower
Manhattan, knocking out power, flooding the tunnels and subway system,
crippling these areas for weeks, destroying billions of dollars worth of
property and causing more than 100 fatalities. No previous storms on record
had behaved the way Sandy did. 2013 continued the trend.
In Fact, Climate Conditions did Become
More Extreme in 2012:
• Floods covered 70% of
Venice, Italy
• Europe had its worst
winter in 25 years.
• Massive floods hit
Australia, China and
• More than 50% of the U.S.
suffered severe drought.
• “Superstorm Sandy”
devastated U.S. East coast
• 50 major wildfires in Chile.
• Record melting of Arctic and
Antarctic ice sheets
• U.S. had the 4th warmest
winter on record.
More of the same in 2013:
• Worst typhoon on record kills over 6000
people in Philippines
• Record number of wildfires in Western U.S.
• Severe tornado season in Oklahoma and
other states
• Continued shrinkage of polar ice caps.
• And more….
Most available data shows that
our climates are changing.
This graph traces temperature variations between
1880 and 2008. It clearly shows that average
temperatures are steadily rising. Source: Berkeley
Earth Surface Temperature Group, 2012
This graph is from a different source but presents
the same conclusion: average temperatures
consistently rose from 1860 to 2009. Source:
Mann & Kump, Dire Consequences: Understanding
Global Warming, London. Darling Kindersley, Ltd,
Ironically, the graph on the left is from a study funded by the Koch Brothers, chief executives of a major corporation which has
consistently denied that Global Warming is occurring or that substances generated by industry are causing climate change.
These graphs, from different sources, tell the
same story. They show an unmistakable trend
toward a warming of the climate since the mid19th century. The graph on the left is
particularly interesting in that it was
commissioned by the leaders of a corporation
determined to disprove the trend toward climate
change and global warming. In spite of their
intentions, the scientists they hired to research
the question reached the same conclusions as
scientists predicting global warming
But, there is disagreement over
why this is happening.
• Is it happening due to
natural causes that are
beyond our control, or…
• Is it caused as a reaction
to man-made changes to
the environment, which we
can control by changing
some of our habits, or…
Could climate change be caused by both
natural cycles beyond our control and
actions and practices of human societies
that could be reversed?
In fact, the evidence seems to prove that there
are both natural and human causes
for the changes we are experiencing.
Before we go further, we need to recognize the
aspects of climate change that we can’t control;
the Natural Causes of Climate Change:
The Earth’s climate has always been subject to
change and has drastically changed many times
in the past.
The earth’s climate is influenced and changed through
natural causes like volcanic eruptions, ocean current, the
earth’s orbital changes and solar variations.
Volcanic eruptions - When a volcano erupts it throws out large volumes of sulphur dioxide (SO2), water
vapour, dust, and ash into the atmosphere. Large volumes of gases and ash can influence climatic patterns
for years by increasing planetary reflectivity causing atmospheric cooling. Tiny particles called aerosols are
produced by volcanoes. Because they reflect solar energy back into space they have a cooling effect on the
world. The greenhouse gas, carbon dioxide is also produced. However, the CO2 produced is insignificant
when compared to emissions created by humans.
(see also featured article - Do Volcanoes cause climate change)
Ocean current - The oceans are a major component of the climate system. Ocean currents move vast
amounts of heat across the planet. Winds push horizontally against the sea surface and drive ocean current
patterns. Interactions between the ocean and atmosphere can also produce phenomena such as El Niño
which occur every 2 to 6 years. El Nino causes deep ocean circulation of cold water from the poles towards
the equator and movement of warm water from the equator back towards the poles. Without this
movement the poles would be colder and the equator warmer. The oceans play an important role in
determining the atmospheric concentration of CO2. Changes in ocean circulation may affect the climate
through the movement of CO2 into or out of the atmosphere.
Earth orbital changes - The earth makes one full orbit around the sun each year. It is tilted at an angle of
23.5° to the perpendicular plane of its orbital path. Changes in the tilt of the earth can lead to small but
climatically important changes in the strength of the seasons. More tilt means warmer summers and colder
winters; less tilt means cooler summers and milder winters. Slow changes in the Earth’s orbit lead to small
but climatically important changes in the strength of the seasons over tens of thousands of years. Climate
feedbacks amplify these small changes, thereby producing ice ages.
Example of Climate Change due to Natural
The “Little Ice Age:” ca.
The first Europeans who we know settled in North America were Viking (Norse) people who
arrived in southern Greenland about 960 A.D. Since the end of the last major Ice Age about
14,000 years ago, this area had warmed considerably, with several periods of climate warming and
cooling, due to natural causes. When the Norse arrived, there were no Native Americans living in
the area, though they had lived there in the past. Around 1200 A.D., Inuit people from the
Canadian mainland also began to arrive and settle in Greenland.
Roughly between 800 and 1300 A.D., the climate in Greenland was relatively mild, and the
Norse were able to live there following many of the same ways of cultivating crops and livestock, and
hunting that they had followed in Scandinavia. They also maintained contact and trade with other
Norse settlements in Iceland, Norway and several other islands.
As the climate began to cool again around 1300, the Norse continued to support themselves as
they had done in the past, but with increasing difficulty. Still, they made minimal attempts to adapt
to the colder weather. The Inuit, on the other hand, changed their habits to fit the new conditions
and survive. What did they change? They expanded their fishing and hunting for seals and whales,
developing sophisticated kayaks tailored to the needs of that environment. Whales and seals
provided them with meat, blubber to burn for light and heat and waterproof skins to make clothing
and boats. They also changed the shelters they lived in during the winters to the cold and windresistant igloo.
By around 1410, the Norse settlements were abandoned. The Inuit still live in Greenland
Source: Diamond, Jared, Collapse: How Societies Choose to Fail or Succeed, 2005.
The climate change that drove the Norse Vikings out of Greenland by 1410 brought even
lower average temperatures and more ice and snow to Europe and North America, with the worst of it
in the period between 1680 and 1730. As the cold period began to slowly dissipate, a period of “global
warming” ensued. Since highly detailed and regular monitoring of the weather was not done on a
regular basis at that time, we must rely on other sources to trace the weather conditions.
Farmers’ records and people’s comments in letters during wartime provide some snapshots of what
was going on for the modern researcher of climate change. During the American Revolution, for
example, British troops drove Gen. Washington’s Revolutionary army out of New York and into
Pennsylvania in the late summer of 1776. Once the winter came on, British leaders were confident
Washington would not be able to launch any kind of military action against them until the Spring. They
left a relatively small force of Hessian troops in Trenton to keep tabs on Washington, settled the main
portion of their troops in the relative comfort of New York City and basically holed up for what they
expected to be a long and bitter winter, typical of that time period.
Washington exploited that assumption by attacking and defeating the Hessians at Trenton in the
middle of a major ice storm, then driving back British troops near Princeton a few days later in what
became a turning point of the war. The weather was so severe, however, that two of Washington’s
soldiers froze to death on the march. But this unexpected victory for Washington saved the Revolution
and convinced the British the war would not be as easy as they had hoped.
In the winter of 1777-78, Washington’s troops, based in Morristown, NJ for the winter,
experienced 22 major snowstorms. That same winter, Washington sent a force of soldiers, horses and
artillery from New Jersey to Staten Island by marching across the ice on New York Harbor, a body of
water normally unlikely to freeze, since the Hudson River waters meet the salt water of the Atlantic at
New York City .
By the time of the Civil War (1861-1865), soldiers reported in their letters numerous
accounts of severe weather, which made their wartime experiences that much more
unpleasant. Now, however, it consisted of more extreme weather on either end of the
temperature scale. Extreme heat, numbing cold, high winds, forest fires, violent storms,
huge downpours leaving seas of mud, flooded rivers and streams and other weatherrelated problems made the Civil War even more difficult for its warriors. One of the
most common accidental causes of death among Civil War troops was drowning.
The Civil War happened at a time of global warming, sparked by natural causes, but
since it was almost a hundred years since the Industrial Revolution had begun in Britain
and at least fifty years since industrialization had begun in the U.S., it’s tempting to
wonder if man-made industrial pollution also had an effect on the intensity of the climatic
shift. As we’ll see a little later, there may have been a man-made cause for the Little Ice
Age in addition to the natural causes.
What Conditions Affect Earth
Greenhouse Gasses :
Carbon Dioxide and
The Industrial Revolution of the 19th century saw the first large-scale use of fossil fuels for industrial
activities. Today, fossil fuels such as oil, coal and natural gas supply most of the energy needed to run
vehicles and generate electricity for industries and households. The energy sector today is
responsible for about ¾ of the carbon dioxide emissions, 1/5 of the methane emissions and a large
quantity of nitrous oxide that go into the atmosphere of the earth.
Carbon dioxide is undoubtedly, the most important greenhouse gas in the atmosphere. A certain
amount of CO2 in the atmosphere is absolutely necessary for life on Earth to survive. However,
changes in land use patterns, deforestation, land clearing, agriculture, and other activities have all led
to a rise in the emission of carbon dioxide. Methane is another important greenhouse gas in the
atmosphere. It is released as a by-product of digestion from plant-eating domestic animals such as
dairy cows, goats, pigs, buffaloes, camels, horses and sheep and many species of plant-eating wild
animals. Methane is also emitted during the process of oil drilling, coal mining, “fracking” methods
for releasing natural gas deposits from shale, leaking gas pipelines, landfills and waste dumps.
The certainty of global warming can be seen through some of the natural phenomenon like the
effect on crops and extreme weather conditions around the world. It is especially clear in the
dramatic change of the polar caps, i.e. the Arctic ice cap is shrinking and the Antarctica ice shelf is
melting. The long-sought “Northwest Passage” allowing passage from the Atlantic Ocean north over
Canada to the Pacific Ocean, long an impossible voyage due to thick ice 12 months a year, is now
open to shipping in the summer. A similar passage allows ships to sail from Western Europe to East
Asia by sailing along the northern coast of Siberia in the summer months for the first time in
recorded history. These are only a few of the many indications of the reality of Global Warming.
The “Greenhouse Effect”
A blanket around the Earth
A blanket around the Earth
es –
as a
to a
e of
NASA Diagram
The last slide is a diagram that shows how the
temperature on the Earth’s surface is
regulated by CO2 and other “greenhouse
gases” released into our atmosphere. As it
shows, a certain amount of greenhouse gases
in the atmosphere are necessary for our
survival. They absorb the sun’s heat, retaining
it in the lower atmosphere, near the Earth’s
surface where it allows the survival of all the
living creatures on Earth, including humans.
More greenhouse gases (which are mostly
CO2) results in higher temperatures on Earth.
Less greenhouse gases absorb and retain less of
the sun’s heat and results in lower
temperatures on Earth. It’s a crucial
balancing act.
This diagram shows how plants
in a natural cycle absorb CO2
while they are living and how
they release CO2 as a gas after
they die and decompose, which
is in turn taken in by newly
growing plants.
This diagram also shows how plants
in a natural cycle absorb CO2 while
they are living and how they release
CO2 as a gas after they die and
decompose, but it also shows what
happens when additional CO2 is
added to the environment. Without
additional plants, the level of CO2
that goes into the atmosphere can
only increase, causing higher air
There is no disagreement with the idea
that climate change has happened before.
There have been many times that the
climate of the earth has become warmer
or colder. In most cases the causes are
naturally –occurring. In some unusual
cases in the past, human activity has
changed the environment enough to
change climatic conditions.
Scientists have Observed
Recent Climate Changes
Are More Extreme Than
Natural Conditions Can
Explain .
If the cause is man-made or even
partially caused by human activities,
changing these activities could
lessen the risk of drastic climate
…But what are we doing that
could cause the climate to
change? And, what can we do to
stop or reverse the damage?
Though climate change due to natural causes has occurred for
millions of years, the current global warming cannot be
explained solely by natural causes. Since 1750, for example, the
average amount of energy coming from the Sun either remained
constant or increased only slightly. If global warming was
caused by a more active sun, then scientists would expect to see
warmer temperatures in all layers of the atmosphere. They have
only observed a cooling in the upper atmosphere, a warming at
the surface and in the lower parts of the atmosphere. This is
due to greenhouse gasses capturing heat in the lower
atmosphere. Also climate models that include solar irradiance
changes cannot reproduce the last century's observed
temperature trend without including a rise in greenhouse gases.
Man-made conditions are the only other alternative.
he last half-century has been caused largely by human activity, such as the burning of fossil fuels and changes in land use, including agriculture and deforestation."
The Royal Society 2010
Human Causes of Climate Change
"It has been demonstrated beyond reasonable doubt that the climate is changing
due to man-made greenhouse gases. We are already committed to future
substantial change over the next 30 years and change is likely to accelerate over
the rest of the 21st century."
The Met Office, Hadley Centre, UK
"There is strong evidence that the warming of the Earth over the last half-century
has been caused largely by human activity, such as the burning of fossil fuels and
changes in land use, including agriculture and deforestation."
The Royal Society 2010
….Two statements from prestigious scientific institutions in the U.K.
(These statements from two respected sources sum up the general consensus
about the causes of recent climate change and global warming. Let’s take a closer look at
how this relationship between greenhouse gases and temperatures on Earth works.)
Here is another statement from a recognized international authority on
Causes of Climate Change
There are many influences over the Earth’s climate, which can be distinguished into
‘natural’ and ‘anthropogenic’ (human-induced) factors. Since the beginning of the
20th century, scientists have been observing a change in the climate that cannot be
attributed to any of the ‘natural’ influences of the past only. This change in the
climate, also known as global warming, has occurred faster than any other climate
change recorded by humans and so is of great interest and importance to the human
population. The following sections look at the main causes of anthropogenic (human
caused) climate change.
Greenhouse gases
The Earth has a natural greenhouse effect where certain gases (known as greenhouse
gases) in the atmosphere allow the sunlight to enter but absorb the heat radiation.
Because these gases absorb the heat, they keep the average surface temperature on
Earth around 14°C.
Since the industrial revolution, human activity has increased the amount of
greenhouse gases in the atmosphere (shown in the graph to the right). The increased
amount of gases which absorb heat, has directly led to more heat being retained in
the atmosphere and thus an increase in global average surface temperatures. This
change in temperature is known as global warming. The increase in temperature is
also leading to other effects on the climate system. Together these affects are known
as anthropogenic (human caused) climate change natural greenhouse effect.
Source: World Meteorological Organization, Geneva, Switzerland
This graph shows Greenhouse gases over the last
2000 years. They remain the same until about
1800, then rise dramatically. The only factor that
changed was the increase in man-made
greenhouse gases.
Although there has been some success
in replenishing forests in the U.S. and
in Europe in recent years, there has
been much more destruction of forest
environments in most other parts of
the world, especially in South
America, Africa and Asia. This has
caused increasing amounts of CO2
that had been contained by forests to
be released into the atmosphere.
Land use change
Land-use changes (e.g. cutting down forests to
create farmland) have led to changes in the amount of
sunlight reflected from the ground back into space.
The scale of these changes is estimated to be about
one-fifth of the effect on the global climate due to
changes in emissions of greenhouse gases. About half
of the land use changes are estimated to have occurred
during the industrial era, much of that due to
replacement of forests by agricultural crops and grazing
lands and the building of cities and highways over
Eurasia and North America.
The largest effect of deforestation is estimated to be at high
latitudes where the reflection of light from snow-covered
land, previously forested, has increased. This is because
snow on trees reflects only about half of the sunlight falling
on it, whereas snow-covered open ground reflects about
Overall, the increased light reflection over Eurasian and
North American agricultural regions has had a cooling
effect. (This could help to counteract some of the warming
produced by other causes.)
Other significant changes in the land surface
resulting from human activities include tropical
deforestation which changes evapotranspiration rates (the
amount of water vapour put into the atmosphere through
evaporation and transpiration from trees), desertification,
which increases surface reflection of light, and the general
effects of agriculture on soil moisture characteristics. All of
these processes need to be included in climate models.
Excuse me: Gassy dinosaurs helped warm Earth
By SETH BORENSTEIN | Associated Press – April 13, 2011
Here’s a case of Climate Change caused by animals.
If they can do it, why not humans?
WASHINGTON (AP) — Potty humor just got prehistoric. A new study suggests that dinosaurs may have helped keep an already overheated
world warmer with their flatulence and burps 200 million years ago.
The research published Monday in Current Biology suggests that large dinosaurs made a significant contribution to the greenhouse effect
back then. Study author David Wilkinson of Liverpool John Moores University in England estimated that about 570 million tons of methane
came from dinosaurs. That's similar to total atmospheric levels of methane today produced by livestock, farming and industry. Cows alone
now produce nearly 100 tons a year of methane.
The study looks at the biggest — and presumably gassiest — dinosaurs, called sauropods. These were the long-necked plant eaters that
munched on the top of trees. They were large animals that had food fermenting in their guts for long periods of time because of their giant
size, said University of Maryland paleontologist Thomas Holtz, who wasn't part of the study.
Wilkinson said dinosaur gas was just one factor at a time when the world was quite tropical, about 18 degrees warmer than now (10 degrees
Celsius). But he said some in the media and blogosphere have misinterpreted his study to say it was the main cause of ancient warming.
In a phone interview, Wilkinson said it was only one of the causes, but dinosaur gas "is big enough to be a measurable effect.“
What caused the ancient pre-human world to be so hot — just the way the dinosaurs needed it — was a variety of factors. Volcanoes
spewed much more greenhouse gases than now, Holtz said. Swamps, water currents, shallow seas and plentiful plankton combined to
raise greenhouse gas levels far higher than today, he said.
Outside climate experts say the study makes some sense, but that the warming from dinosaur gas back then is dwarfed by man-made
carbon dioxide today from industry.
NASA climate scientist Gavin Schmidt quickly ran some calculations based on Wilkinson's figures. Dinosaur methane would have hiked
temperatures about half a degree (0.3 degrees Celsius), which is a fraction of what's been caused by the burning of fossil fuels like coal
and oil in the 20th Century, he said.
Has human activity ever caused climate change before?
Here are two accounts of recently discovered human activity that changed
the climate thousands of years ago
Humans Drove Rainforests into Savannah in Ancient Africa
(02/09/2012) Three thousand years ago (around 1000 BCE) several large sections of the Congo rainforest in
central Africa suddenly vanished and became savannah. Scientists have long believed the loss of the forest was
due to changes in the climate, however a new study in Science implicates an additional culprit: humans. The
study argues that a migration of farmers into the region led to rapid land-use changes from agriculture and iron
smelting, eventually causing the collapse of rainforest in places and a rise of grasslands. The study has
implications for today as scientists warn that the potent combination of deforestation and climate change could
flip parts of the Amazon rainforest as well into savannah.
Democratic Republic of the Congo
About 3000 years ago, much of central Africa changed from rain forest to savanna, and it’s been thought that
natural climate change was the cause. Marine sediment cores from the mouth of the Congo River suggest ,
however, that forest clearance, intensive land use, and increased soil erosion occurred at the same time –
implicating Bantu-speaking farmers, who began to spread across the region at that time. Their forest clearing
for agriculture and iron smelting might have contributed to the widespread shift in central Africa’s
Archeaology, May/June 2012, p.22
The articles above show that as far back as 3000 years ago, human activity was extensive enough to
have caused a significant change in the physical environment, in this case, causing the demise of rain
forests in some sections of Africa, changing them into open grasslands.
Was this Level of Human
Activity Extensive Enough to
Have Affected Climate
Recent scholarship strongly
suggests that it was. In a
paper published in 2010 in the
Annals of the Association of
American Geographers, a team
of scholars reports on a similar
situation occurring in South
“Pre-Columbian farmers of the Neotropical Lowlands numbered an
estimated 25 million by 1492, with at least 80 percent living within forest biomes. It
is now well-established that significant areas of Neotropical forests were cleared
and burned to facilitate agricultural activities before the arrival of Europeans.
….The introduction of Old World diseases (introduced by European settlers) led to
recurrent epidemics and resulted in an unprecedented population crash throughout
the Neotropics. The rapid demographic collapse was mostly complete by 1650, by
which time it is estimated that about 95% of all indigenous inhabitants of the region
had perished. We reviewed fire history records from throughout the Neotropical
lowlands and report new high-resolution charcoal records and demographic
estimates that together support the idea that the Neotropical lowlands went from
being a net source of CO2 to the atmosphere before Columbus to a net carbon sink
for several centuries following the Columbian encounter.
We argue that the regrowth of Neotropical forests following the
Columbian encounter led to territorial biospheric carbon sequestration on the order
of 2 to 5 PgC, thereby contributing to the well-documented decrease in atmospheric
CO2 recorded in Antarctic ice cores from about 1500 through 1750, a trend previously
attributed exclusively to decreases in solar irradiance and an increase in global
volcanic activity. We conclude that the post-Columbian carbon sequestration event
was a significant forcing mechanism of Little Ice Age cooling.”
That’s quite a Mouthful !!! What does it
It means that Native American farmers before Columbus, in
order to open up farmland, burned enough rainforest that
the CO2 they released into the air in the process
contributed to raise the temperature level of the planet.
When most of those people died off in epidemics
brought by the Europeans, the forests grew back, with trees
holding CO2 in their trunks, preventing the CO2 from
entering the atmosphere. The result was an increase in the
cooling of the climate, partly the result of human activity,
not simply natural causes like solar fluctuations or volcanoes
throwing ash into the atmosphere. This climate change has
become known as the “Little Ice Age,” and it seems clear
that human activity contributed to it in its later stages.
But Wait…..
Wasn’t the “Little Ice Age” caused by
natural causes?
There were natural causes that contributed
to the “Little Ice Age.” Recent research,
however, as the last reading demonstrates,
reveals that human actions on the land also
did play a role in the change of climate
making it turn colder, and probably stay
colder longer.
To put this into perspective, the “Little Ice Age”
began, most likely, due to natural causes. The
Norse Vikings abandoned their settlements in
Greenland, due to the climate change, about 150
years before Columbus and company arrived in
Central America and unwittingly introduced the
European diseases that wiped out most Native
Americans, causing them to abandon their
farmlands. The change from farmlands to rain
forest that resulted, however, could very well
have been one of the causes of the reduction in
CO2 in the atmosphere that followed,
contributing to a longer and/or cooler “Little Ice
Age” than may otherwise have occurred.
The Dust Bowl of the 1930’s
A more recent example of human actions
affecting climate change took place in the 1930’s,
within the timeframe studied in American History
II. As if the Great Depression wasn’t bad enough
at that time, the agricultural center of America
actually dried up and blew away too. Partly caused
by natural weather conditions like el Nino, the
severe droughts and dust storms on the Great
Plains were also caused by man-made changes to
the environment.
The Great Plains had been dry grasslands for millennia before Americans
developed the technology to turn them into the breadbasket of the continent in
the later decades of the 1800s. Earlier explorers of the region had called it “the
great American desert,” but that all changed with the new technology available
after the Civil War. The coming of the railroad, the availability of less- expensive
steel plows and mechanized farm equipment made it more possible to get
farmers on the land, the land plowed in furrows and sowed with crops like corn
and soybeans, and the resulting crops transported to market. As many new
farms filled the nation’s appetites, however, crop prices began to fall, and farmers
responded by growing more, trying to stay ahead of the curve. More land was
ploughed in long, straight furrows for planting, which also allowed water to run
off faster to streams and rivers, taking nutrients from the soil with it. Strong ,
resilient prairie grass was replaced with wheat, corn and soybean which absorbed
more nutrients from the soil. Forests in the northern plains were cut down to
meet the demand for lumber in the rest of the country, causing a greater release
of CO2 into the atmosphere and causing faster runoff of water from the land
where the trees once grew to the streams and rivers to the south. The water
drained off the land through the Mississippi River system and into the Gulf of
Mexico, taking the nutrients in the soil with it.
The “Dust Bowl”
What was left blew away with the wind, also scattering the farmers who had worked that land
along a thousand mile section from the Mississippi to the Rockies and from Texas to the
northern plains. The fact of the Great Depression at that time didn’t make things any easier.
It would be well over a decade before the land began to recover, and better farming methods
made farming possible again.
Resource Usage in the Post-WW II World
Before the 1930s, most CO2 emissions came from burning wood and coal, and from cutting
down forests, but by the 1930s, petroleum had become a major source of CO2 emissions as
well. Cars, powered by gasoline engines, had become commonplace, causing new increases
in CO2 emissions. The development of appliances powered by electricity generated in coalfired powerplants released even more CO2 into the air. At first, gas was cheap in America
and American automakers took advantage of that to produce big, powerful cars that used lots
of gasoline, a trend that lasted well into the 1970s.
By then, the U.S., a major oil producer, used so much gasoline that it became dependent on oil
imported from middle eastern countries to keep its engines running, a dependency that
resulted in U.S. involvement in three wars and numerous terrorist attacks between 1989 and
The demands of the expanding aviation industry, the military needs of the Cold War for all
sides, the growing populations of the U.S. and Western Europe, overshadowed by the population
growth in countries like India and China, all resulted in massive increases in the use of fossil fuels
around the world.
This increase had some major side effects. One was a dependency on this technology
among people all over the world. Another was the growth of extremely powerful corporations which
provided the fossil-fuel energy that kept these countries going.
By the 1980s, a realization had set in that there was a need to scale back our dependence
on fossil fuels, but there was already such a dependence on them among most people that this would
prove difficult. Another problem was the resistance of the powerful fossil fuel companies to any
attempt to cut back on consumption.
The United States : 1950s to 2014
from Consensus to Polarization
For a variety of reasons over the last 60 years,
Americans in the early 21st century have become as
divided as they have rarely been before. Political parties
are deadlocked against each other and the people are
decidedly not all on the same page over many issues.
Economic inequality, at a higher level than usual, feeds
this trend.
As with most public issues, Americans are divided
over the issue of climate change. There is conflict over
whether climate change is happening at all and there is
conflict over what to do about it if it is happening.
It is a goal of this course to get past the political
points of view and address the reality of our common
In Spite of the Evidence, Many People Today Don’t
Believe that Climate Change is Being Caused by Human
While scientists specializing in climatology are convinced
that human activities are affecting the earth’s climate, there are many
other people who are not convinced, and this has become a major
and contentious political issue as well as a major factor in the national
and world economy. Very often, the climate change skeptics are
people with limited understanding of how the climate system works
or people with vested economic or political interests in maintaining
things the way they are. Whatever their motives or level of
knowledge, these people’s opinions have influenced many others and
must be addressed if the factors that are making climate change more
extreme are to be reduced.
Since the Industrial Revolution became a significant factor in
climate change, a counter-productive force has developed among
many of the industries whose economic interests are based on
selling the products and services that contribute to climate
change and global warming. While some corporate leaders
recognize the profit opportunities from providing more
ecologically-friendly products and services and realize the longterm negative consequences of continuing our current practices,
many more are reluctant to change industries which have
provided them with lucrative profits in the past.
The strategy of many of these corporate leaders, and
their political representatives in world capitals, has become to
deny that there is a problem, publicize their skepticism of
climate change in public statements and simplistic TV
commercials, and raise doubts about what the scientific
community has come to accept as true regarding the current and
future changes in Earth’s climate.
Political leaders and advertising agencies hired by the
corporations denying climate change are trained
experts in shaping and changing public opinion. They
might have a distinct advantage over scientists, who
are skilled in other areas such as research and
objectivity. Many people have been swayed by the
corporations’ reassurances that we have little to fear
from continuing our current reliance on burning fossil
fuels for energy indefinitely.
Climate scientists, on the other hand, have collected
a weighty amount of evidence that human activity is
causing environmental changes that can only get
worse if we continue putting large quantities of
greenhouse gasses into the atmosphere and polluting
or destroying our other natural resources.
Scientists, unlike some other professions, have no
financial advantage in promoting ideas or policies
that are untrue. Scientists who are proven wrong
lose, as far as their career advancement is concerned.
They have no ulterior motive to mislead the rest of
us. Yet, as this cartoon points out, they can be
intimidated, threatened or criticized by others with
hidden agendas to discredit what the scientists are
telling us about their research.
Not all opposition to the findings of climate scientists comes
from corporate CEO’s trying to protect their bottom line or
politicians looking for campaign contributions from those
corporate CEO’s. A lot of opposition also comes from people
with no dark agenda or sinister plans to mislead us. Many of
them are average people with average intelligence who simply
want to live their lives without a lot of extra problems.
They’ve got enough problems already. They hear about
climate change and possible bad effects, but they don’t see it
happening that much yet and start hoping it won’t happen at
People often respond most actively to what most
immediately affects them. They hear the scientists, but then
they read a blog on the internet by a retired middle manager
from Kansas City who’s actually a pretty good writer. He tells
them, “Everything’s OK. The global warming crowd are a
bunch of wacko’s who think they know more than you do.
Don’t worry about it.” The result is that they reject what the
climate scientists tell them that makes them uncomfortable,
and quote their favorite self-appointed expert, who tells them
what they want to hear.
The evidence supporting climate
change and its connection to
human activity, however, is
abundant and clear.
Its effects are happening today and
will continue.
• Some causes of climate change may
be natural causes, beyond our
• Some of the human-caused sources
of climate change may already be
• BUT, in any case, the sooner we act
to limit or eliminate the humancaused sources of climate change,
the less severe the effects of climate
change will be.
Annotated List of Resources: Here’s only some of the huge
amount of information available on this topic
Diamond, Jared, Collapse: How Societies Choose to Fail or Succeed, Penguin Books, 2005.
Describes how different societies have succeeded or failed in meeting serious
environmental challenges.
Gore, Al, Our Choice, A Plan to Solve the Climate Crisis, Rodale Publishing, 2009.
Provides persuasive arguments related to the political, economic and logistical
problems associated with climate change issues, and understandable yet detailed
explanations of a wide range of possible climate change solutions.
Gore, Al, The Future: Six Drivers of Global Change, New York; Random House, 2013.
National Academy of Sciences,, Understanding and Responding to Climate Change,
The National Academies, 2008.
“Berkeley team announces early results from global warming review,” Research team funded by Global
Warming denier publishes research results supporting claims of Global Warming advocates.
Intergovernmental Panel on Climate Change (IPCC) – Website provides access to reports of the IPCC
back to 1995. These are considered to be the most authoritative, comprehensive review of climate
change science and related areas of knowledge.
NASA Global Climate Change – provides high quality scientific overviews of climate change evidence,
causes, effest, and uncertainties, graphics and images, interactive tools for learning about climate,
NASA climate research.
US Global Change Research Program – Multi-agency program of the federal government on climate
change science and impacts. Reports that synthesize information from a wide range of research
activities on their website.
Annotated List of Resources:
NOAA Climate Services – “One-stop-shop” for climate data and info. Climate Watch
magazine has good articles on climate science accessible for undergraduate readers. Nic
collection of videos.
USEPA Climate Change Website – Access to info about greenhouse gas emissions, climate
change science, health and environment effects of climate change, climate economics, US
climate policy and ideas for what you can do.
National Climate Data Center for Paleoclimate Data – provides data sets for researchers
using tree rings, ice cores, pollen, coral,speleothems, and instrumental climate data
Many additional websites from the NASA Cooling the Curriculum Climate Modeling
Workshop at Dickinson College in Aug. 2011 are also available. Contact
[email protected].
Cronon, William, Changes in the Land: Indians, Colonists, and the Ecology of New England
(New York: Hill & Wang, 1983; 20th anniversary edition, 2003).
Cronon, William, Nature’s Metropolis: Chicago and the Great West (NY, 1991)
Hughes, Thomas, Networks of Power: Electrification in Western Society, 1880-1930,
(Baltimore, 1983)
Mann, Charles, 1491 (2006) - An account of the recently revised history and archaeology
of the Americas before the arrival of Europeans, revising earlier assumptions about
the extent to which they altered their physical environment.
Annotated List of Resources
“Teachers Endure Balancing Act Over Climate Change Curriculum”, Conversation with
teachers and parents regarding teaching about climate change in Colorado where
climate change deniers are in the majority.
World Data Center for Human Interactions in the Environment (WDC) – provides open
access to a wide range of geophysical, environmental and social science data
related to the environment and sustainable development.
“USS Constitution Weathers Hurricane Sandy” Nov. 16,2012
Miller, Peter, “Weather Gone Wild,” Naational Geograaphic, 2010.
Dull, Robert A. , et al., “The Columbian Encounter and the Little Ice Age: Abrupt Land use
Change, fire and Greenhouse Forcijnng,” Annals of the Association of American
Geographers, (2010)
Oreskes, Naomi, Answering Climate Change Critics,
Goodell, Jeff, As the World Burns, January 6, 2010, :
Ropiek, David, The Ethics of Climate Change Denial, Feb. 1, 2012
Vidal, John, Bill Gates backs Climate Scientists Lobbying for Large-scale
Geoengineering, The Guardian,, Feb 5, 2012.
“Can China Go Green”, National Geographic, June, 2011.
Green, Peter, “Weather Gone Wild” National Geographic, 2010
Gillis, Justin, “ Are Humans to Blame? Science is Out”, New York Times,
October 31, 2012..
Goodell, Jeff, “As the World Burns: How Big Oil and Big Coal mounted one of
the most aggressive lobbying campaigns in history to block progress on
global warming” , Rolling Stone, January 6, 2010
Mann, M. E. and Kump, L. R. Dire Consequences: Understanding Global
Warming. London: Dorling Kindersley Ltd., 2009, p. 36.
Hernandez, Raymond, “Bloomberg Backs Obama, Citing Fallout From Storm”
New York Times, November 1, 2012 .
Goodell, Jeff. “Can Geoengineering Save The World? The Pentagon's top
weaponeer says he has a radical solution that would stop global warming
now.” Rolling Stone, October 4, 2011
U.S. Climate Change Research Program, “Past Climate Change”, U.S. Dept. of
Environmental Protection, April 14, 2010.
---“Causes of Climate Change”
---“Future Climate Change”
---“Recent Climate Change”
---“Health and Environmental Effects”
InnovationNewsDaily Staff, “Changing Earth: 7 Ideas to Geoengineer Our
Planet”, May 18, 2012.
Goodell, Jeff, “Climate Change and the End of Australia” “Rolling Stone”,
Susan Culver-Graybeal, |“Man-Made Climate Change Debate Hits the
Classroom” Yahoo! Contributor Network , Jan. 7, 2012.
Marshall, George, “Climate Change Denial: DO SCIENTISTS REALLY
Latham, Mark, “Climate change denial not just for fools,” The
Australian Financial Review, Apr 20, 2012
Skeptic’s Dictionary, “Climate Change Deniers”, April 14, 2012.
AFP, “Climate Change Driving Australian Fish South”, Aug. 17, 2012
Doyle, Alister, “Climate change poses risks to food, beyond U.S. drought”
| Reuters , Aug 16, 2012
AFP. “Climate change to blame for extreme heat: NASA scientist” Aug. 4., 2012
The National Academies, Understanding and Responding to Climate Change,
2008 Edition.
Muller, Richard, “The Conversion of a Climate-Change Skeptic” NY Times, July
28, 2012.
Chestney, Nina, “Countries Doing Too Little on Warming - Researchers”
Reuters, May 24, 2012.
Mandia, Scott A., “Determining the Climate Record” [email protected].
Diagram Comparing Views on Global Warming, July 6, 2012.
Krumboltz, Mike, “Atlantis Found? Doggerland artifcats on Display at London
Museum” The Sideshow, July 4, 2012
Spinney, Laura., “Searching for Doggerland” National Geographic, December
Lavelle, Marianne, “Fracking for Methane: Good Gas, Bad Gas” National
Geographic, December 2012.
NASA, “The Current and Future Consequences of Global Change” November
Thagard, Paul, “Emotional Causes of Climate Change Denial ; Why do
bad ideas happen to good people? “ Published on October 28,
2011 in Hot Thought
Mandia, Scott, “The End of the Vikings in Greenland,”
[email protected].
AFP , “Environmental Collapse now a serious Threat: Scientists” 6/6/2012.
EPA, “Summary of Key Findings
AFP, “European Climate Change to Hit Scandinavia and South Hardest” May 1,
NASA, “Climate Change: How do we Know?”
Borenstein, Seth, “Excuse Me: Gassy Dinosaurs Helped Warm Earth” Associated
Press, Aug. 13, 2011.
Masters, Jeff, reposted from WunderBlog, “Masters: “It Is Very Likely That This
Has Been the Driest First Week of January in U.S. Recorded History”
The Extinction Protocol , “Extreme weather patterns may worsen in
2012 says NASA scientist” February 26, 2011
CLIMATE CHANGE” pp 174-75 in Mann, Michael E. and Kump,
Lee R. Dire Consequences: Understanding Global Warming.
London: Dorling Kindersley Limited, 2009.
Whittington, Mark, “Former Astronauts, Scientists Warn NASA on Global
Warming” Yahoo Contributor Network. April 10, 2012
Bryner, Jeanna, “Global Warming Fight Could Turn Skies Brighter,
Whiter”,,, June 6, 2012.
Lakoff, George, “Global Warming Systemically Caused Hurricane
Sandy” , 10/30/2012.
McKibbon, Bill, “Global Warming's Terrifying New Math: three simple
numbers that add up to global catastrophe - and that make clear who the
real enemy is” Rolling Stone, August 2, 2012.
Ropeik, David, “Heartland Billboards on Climate Change. The Dangerous
Ignorance of Ideology” May 4, 2012.
Kunzig, Robert, “Hothouse Earth: World Without Ice” National Geographic,
Oct. 2011.
Choi, Charles, “Huge Ancient Civilization’s Collapse Explained” Live, May 29, 2012.
“Hurricane Sandy a Boon to Global Warming Speculation”, The Daily
Caller, November 1, 2012.
Mandia, Scott, “Impact of the Little Ice Age” Mandias
Banerjee, Neela, “Kock-funded climate change skeptic reverses course”
- skeptic-reverses-course- 20120729, 0, 73 72823 . Story
“Earth’s Changing Climate”, National Geographic, July 2012.
Borenstein, Jeff, “New Study Ties Global Warming to Recent World Heat”
,Associated Press, Aug. 4, 2012.
Sheridan, Kerry, “No link between tornadoes and climate change: US”,
Parish, Ken, “The Big Bangs: (Nuclear Blast Effects on Climate Change)”
“Atmospheric nuclear testing stagnated mid 20th century global warming”,
Climate Citizen, Jan. 21,2011.
Watts, Anthony, “Climate Craziness of the week – Claim: nuclear tests stopped
global warming in the mid 20th century” , What’s Up With That
(WUWT), April 4, 2011.
Carol;, Lawrence, “The Climate Change Disaster You Didn’t know Existed”
“”, August 6, 2012.
Revkin, Andrew C.. “On Hurricanes, Presidents, Climate and One Clear Human
Factor in the Sandy Disaster” Nov. 2. 2012.
Zuckerman, Esther, “Only 2% of Canadians Don’t Think Climate Change is
Happening”, Atlantic Wire, August 16, 2012.
Doyle, Alister, “Parasites May Get Nastier with Climate Swings: Study” Reuters, Aug.
12, 2012.
Main, Douglas, “What’s Behind the Record Heat?” Live Science, July, 4, 2012.
AFP, “Rising Sea Level Puts US Atlantic Coast at Risk: Report”, June 24, 2012.
Berger, Eric, “There Will Probably be Fewer Sandy-like Storms in the Future” SciGuy,
A Science Blog with Eric Berger, November 2, 2012.
USDEP, “IPCC Special Report on Managing the Risks of Extreme Events and
Disasters to Advance Climate Change Adaptation:” US Global Research
Program, May 5, 2012.
National Oceanic and Atmospheric Administration, National Climatic
Data Center, “State of the Climate: National Overview’, Feb. 2012.
“Teachers Endure Balancing Act Over Climate Change Curriculum” May 4, 2012..
The Climate Change Journal, “Our Approach to Climate Change and Global
Warming,” July 12, 2011.
Oblack, Rachel, “The Dust Bowl - What Caused the Dust Bowl in the US Midwest in
the 1930's?” (includes website entries about the Dust Bowl from
NASA and Wikipedia).
Parker, Geoffrey, “AHR Forum : Crisis and Catastrophe: The Global Crisis of the
Seventeenth Century Reconsidered “ University of Chicago Press,
Fagan, Michael, “ The Great Warming: Climate Change and the Rise and Fall of
Civilizations.” Bloomsbury Press.
Fagan, Brian, The Little Ice Age, Basic Books
Gillis, Justin, “ The Issue that Dare Not Speak Its Name”, Green – A blog About Energy
and the Environment, New York Times, 10/23/2012.
Manning, Richard. “The Oil We Eat: Following the Food Chain Back to Iraq” July 23,
Mandia, Scott, “Global Warming: Man or Myth, The Scientific Consensus”
[email protected], 2/13/2011.
Levin, Kelly, “Timeline, Extreme Weather Events in 2012”, WRI Insights,, Sept. 6, 2012.
Rogers, Stephanie, “Top Ten Global Warming Deniers”, News and Culture, Oct. 11,
Roman, Joe, “Update: Tornadoes, Extreme Weather and Climate Change, Revisited,
Mar. 4, 2012., “Number of Tornadoes in US by Year”
Tornado accounts in 17th-18th century New England
NASA Jet Propulsion Laboratory, CalTech, “Unresolved Questions About
Earth’s Climate
Freeman, Tita, “Climate Change – We Need a Different Approach” Free
Enterprise, U.S. Chamber of Commerce, Nov. 3, 2009.
“Weather During the Civil War”, June 28, 2011
Trimarchi, Maria, “What Caused the Dust Bowl?”
Hsu, Jeremy, “What Country Faces the Worst Climate Change?”,
Aug. 14, 2012.
National Wildlife Foundation, ,”What is Global Warming?” May 1, 2012.
Walsh, Bryan, “ Why the Argument over Climate Change and Tornadoes is
Pointless”, May 26, 2011.
Kunsig, Robert, “World Without Ice” National Geographic, October 2011.
Bigelow, Bill, “The Mystery of Three Scary Numbers: Using Simple Math to Teach
Students the Impact of Climate Change”, UTNE Reader, Jan.-Feb. 2014
Goodell, Jeff, “Climate Change and the End of Australia,” Rolling Stone, October
13, 2011.
Bibliography (Cont.)
“Twelve Thousand Years Ago,” Scientific American, December, 2002.
Main, Douglas, “Extreme Weather 2011: What Fueled Climate Chaos,” Live Science, 7/10/2012
Sutherland, Scott, “New Reports Reveal the Dire Picture Humanity is Painting for Earth’s
Climate,” Aug. 7, 2013,
“2012 State of the Climate,” National Climate Data Center.
Main, Douglas, “”On the Brink: Climate Change Endangers Common Species,” May 12, 2012,
Zap, Claudine, “Does this Photo of Alaska Show a Troublesome Trend?” The Slideshow, June 17,
Borenstein, Seth, “Warming Report Sees Violent, Sicker, Poorer Future,” Associated Press,
November 2, 2013.
The Intergovernmental Panel on Climate Change,
McKibben, Bill, “Global Warming’s Terrifying New Math”, Rolling Stone, Aug. 2, 2012.
List of Videos dealing with Global Climate
Global Warming: Science and Solutions ,
(Ambrose Video, 2006)
Global Warming: The Signs and the Science,
(PBS Video, 2005)
The Story of Stuff, (Free Range Studios, 2007)
The 11th Hour (Warner Video, 2007)
An Inconvenient Truth: A Global Warning
(Paramount Pictures, 2006)
Student Assignments and Projects
Reading Assignments:
1. Read Chapters 6,7 and 8 (pp. 178-276) in Collapse: How Societies Choose
to Fail or Succeed, by Jared Diamond. Deals with the comparison between
the Viking settlers to Greenland and the Inuit settlers, who both migrated
there about the same time and coped with climate change there in very
different ways.
2. Read Chapters 1 and 2 (pp. 30-62) of Our Choice: A Plan to Solve the
Climate Crisis, by Al Gore. Dealing with how our current energy system
works and how it affects to ecosystem.
3. Read Chapters 14, 16 and 18 of Our Choice, which outlines strategies to
change energy policies and deal with conflicts.
Research Assignments:
1. Based on articles related to tornadoes as indicators of climate change, write
about the difficulties involved in using tornado data as a determinant of
climatic change and causes.
See, “Tornado Accounts in 17th and 18th century New England”
“, “Tornado
trends over the last thirty years”
“UPDATE: Tornadoes, Extreme Weather And Climate Change,
Number of Tornadoes in US by Year
3. Research Paper: Based on your reading and material presented in class,
formulate a topic involving the interaction of climate change and human
action in American History. Research the topic, decide on a thesis and
submit a 6-10 page paper to prove your position.