Human behavior refers to the array of every physical action and observable
emotion associated with individuals, as well as the human race as a whole. While
specific traits of one's personality and temperament may be more consistent, other
behaviors will change as one moves from birth through adulthood. In addition to
being dictated by age andgenetics, behavior, driven in part by thoughts and feelings,
is an insight into individual psyche, revealing among other things attitudes and
values. Social behavior, a subset of human behavior, study the considerable influence
of social interaction and culture. Additional influences include ethics, encircling,
authority, rapport, hypnosis, persuasion andcoercion.
The behavior of humans (and other organisms or even mechanisms) falls
within a range with some behavior being common, some unusual, some acceptable,
and some outside acceptable limits. In sociology, behavior in general includes actions
having no meaning, being not directed at other people, and thus all basic human
actions. Behavior in this general sense should not be mistaken with social behavior,
which is a more advanced social action, specifically directed at other people. The
acceptability of behavior depends heavily upon social norms and is regulated by
various means of social control. Human behavior is studied by the specialized
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academi disciplines of psychiatry, psychology, social work, sociology, economics,
and anthropology.
Human behavior is experienced throughout an individual’s entire lifetime. It
includes the way they act based on different factors such as genetics, social norms,
core faith, and attitude. Behavior is impacted by certain traits each individual has.
The traits vary from person to person and can produce different actions or behavior
from each person. Social norms also impact behavior. Due to the inherently
conformist nature of human society in general, humans are pressured into following
certain rules and displaying certain behaviors in society, which conditions the way
people behave. Different behaviors are deemed to be either acceptable or
unacceptable in different societies and cultures. Core faith can be perceived through
the religion and philosophy of that individual. It shapes the way a person thinks and
this in turn results in different human behaviors. Attitude can be defined as "the
degree to which the person has a favorable or unfavorable evaluation of the behavior
in question."
[1]
One's attitude is essentially a reflection of the behavior he or she will
portray in specific situations. Thus, human behavior is greatly influenced by the
attitudes we use on a daily basis.
Global Warming
Light from the Sun passes through the atmosphere and warms Earth's surface.
The energy associated with heating is re-radiated as infrared light absorbed in the
atmosphere by greenhouse gases, including carbon dioxide (CO2), water vapor,
methane
(CH4),
ozone,
nitrous
oxide
(N2O),
and
the
human-
madechlorofluorocarbons (CFCs). This atmospheric warming is called the
greenhouse effect and is both natural and essential for life on Earth. Without the
greenhouse effect, Earth's average global temperature would be too cold to support
most forms of animal and plant life. However, an overabundance of greenhouse gases
can increase the greenhouse effect and force abnormal global warming.
Carbon dioxide--a by-product of burning fossil fuels and modern forests--is the
most abundant greenhouse gas. Depending on the specific measurements, in the early
twenty-first century, there is at least 30 to 40 percent more CO
2
in the atmosphere
than in 1850. There have also been significant increases in methane, a more potent
greenhouse gas.
In some ways, adding greenhouse gases to the atmosphere is like throwing
another blanket on Earth; the consequent rise in global temperature is known as
global warming. Despite the fact that climate is a complex system and climate models
are difficult to construct, scientists must use climate models to predict the impacts of
various concentrations of greenhouse gases on global warming, and in turn, on global
climate. Some models show average global temperature increasing as much as 9
degrees Fahrenheit (5 degrees Celsius) by 2100. Because ocean water absorbs more
heat than land, the Southern Hemisphere (which has more water) will warm less than
the Northern Hemisphere, hence, any temperature increase will not be uniform.
Atmospheric circulationpatterns will bring the greatest warming, as much as 14 to 18
degrees Fahrenheit (8 to 10 degrees Celsius), to Earth's poles.
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Since the IPCC's 2007 report, new scientific findings have tended to worsen
the climate change picture. In early 2009, scientists at two major gatherings--one at
the University of Copenhagen, the other at the annual meeting of the American
Association for the Advancement of Science--presented evidence that climate change
was occurring more quickly than the IPCC had conservatively forecasted in 2007. In
addition, carbon dioxideemissions increased faster than the IPCC's most pessimistic
forecasts.
Climate change skeptics often cite Berkley professor of physics Richard A.
Muller's (1944-) past criticisms of the scientific consensus on anthropogenic climate
change. In 2010, Muller founded the Berkeley Earth Surface Temperature Study to
analyze climate data. In 2012, Muller recanted his skepticism over anthropogenic
climate change, titling his op-ed in the New York Times "The Conversion of a
Climate-Change Skeptic." Muller states that his work at Berkeley Earth provides the
most convincing evidence to date that human activity over the last 250 years has
altered Earth's climate. Muller notes that his findings go even further than the 2007
Intergovernmental Panel on Climate Change (IPCC) Assessment Report, which only
attributed temperature rises since the mid-twentieth century as "very likely" due to
human activity.
Climate History
In addition to concentrations of greenhouse gases in the atmosphere, other
factors affecting global climate include Earth's orbital behavior, the positions and
topography of the continents, the temperature structure of the oceans, and the amount
and types of life on Earth. During much of Earth's history, the climate was warm and
humid with ice-free poles. Global average temperatures were about 9 degrees
Fahrenheit (5 degrees Celsius) higher than today. Glaciers covered the higher
latitudes several times in the past, most recently during the Pleistocene Era (about 1.8
million to 10,000 years ago), when up to 30 percent of the land was covered by ice.
During the four glacial advances of the Pleistocene Era, average global temperature
was 18 degrees Fahrenheit (10 degrees Celsius) lower than the ancient global
average. During the three interglacial periods, global temperature was a degree or two
warmer than today.
Climate Change
According to the IPPC and the vast majority of global leaders and climate
experts, climate change driven by AGW will fundamentally impact the security,
health, and global economy of nations for generations. Hundreds of millions of
people and scores of societies, economies, and cultures are already threatened by
rising sea levels, disrupted food production, extreme weather, and emergent diseases.
While such irreversible losses as speciesextinctions and lost lives cannot be
calculated in monetary terms, the most conservative estimates of the costs of climate
change over the next century range in the trillions of dollars. Moreover, the most
severe effects of climate change are predicted to most strongly impact the world's
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poorest and most vulnerable human populations.
Abnormal warming
Since the peak of the last glacial advance 18,000 years ago, average global
temperature has risen approximately 7 degrees Fahrenheit (4 degrees Celsius),
including 1.8 degrees Fahrenheit (1 degree Celsius) since the beginning of the
Industrial Revolution. The recent increases in temperature since the Industrial
Revolution, however, are unprecedented and not accounted for by natural cycles. In
fact, recent global warming has taken place during a cycle in which many other
factors favor global cooling. Although regions vary, according to the IPCC, between
1905 and 2005, the overall average global surface temperature on Earth increased by
approximately 1.33 degrees Fahrenheit (0.74 degrees Celsius).
Predicted Impacts of Global Warming
In addition to ecological impacts, a rapid increase in global average
temperature will have profound effects on economic infrastructure as well as cultural
and political systems.
Warmer average temperatures
According to most climate change models, not all regions will experience
warmer temperatures. In fact, due to increasing humidity and cloud cover, some
regions might experience (at least initially) cooler temperatures and increased
snowfall. There also might be intervals during which temperature increases stop and
perhaps modestly decline (especially after significant increases or sharp spikes in
temperature, such as recorded in 1998). However, average global atmospheric, land,
and sea temperatures are expected to rise over the next century.
Warmer temperatures would allow tropical and subtropical insects to expand
their ranges, bringing tropical diseases such as malaria, encephalitis, yellow fever,
and dengue fever to more human populations. There would be an increase in heat-
related diseases and deaths. Agricultural regions might become too dry to support
crops, and food production all over the world would be forced to move northward.
This would result in a loss of current cropland of 10 to 50 percent and a decline in the
global yield of key food crops of 10 to 70 percent.
Most computer models of global climate predict that high latitudes will
experience the greatest intensity of climatic warming. Ecologists have suggested that
the warming of northern ecosystems could induce a positive feedback to climate
change. For example, the huge expanse of boreal forest and arctic tundra normally
forms sinks, or reservoirs, that store atmospheric CO
2
. If the climate continues to
warm, these typically frozen carbon sinks would begin to thaw. Eventually, the depth
of annual thawing of frozen soils would expose large quantities of carbon-rich
organic materials in the permafrost to microbial decomposition, thereby releasing
vast quantities of methane into the atmosphere.
Sea level rise
Sea levels have risen and fallen due to natural causes many times over Earth's
history. However, during what should be a cooling period, warmer ocean
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temperatures are already causing ocean water to expand and polarice caps to melt.
Forecasts as to the amount and timing of sea level rises are scientifically contentious,
but all forecasts predict potentially devastating increases over the next decades and
centuries. In 2007, the IPCC predicted a rise between 18 and 59 centimeters (7 and 23
inches) by 2100. However, a number of scientists have argued in leading scientific
journals that the future sea level rise may be greater than the IPCC's 2007 forecast
and is unlikely to be less.
In 2009, new data on glacial melting and sea level rise forced scientists to
dramatically increase estimates of potential sea level rise and/or accelerate the rate of
rise. The new data predict a sea level rise of at least 1 meter (a little more than 3 feet)
by 2100. Such an increase in sea level will flood coastal regions, where about one-
third of the world's population lives and where an enormous amount of economic
infrastructure is concentrated. It would destroy coral reefs, accelerate coastal erosion,
and increase the salinity of coastal groundwater aquifers. Some low-lying tropical
Pacific islands are already losing land to rising seas, and on some, residents are
planning to leave as the sea engulfs their island homes.
Changes in precipitation amounts and patterns
As globally averaged temperatures rise, scientists predict moderate to severe
alterations in precipitation regimes in various parts of the world. According to some
climate models, at the current rate of warming, precipitation patterns will change so
that one-third of the planet will be considered desert by 2100. The percentage of the
globe that is now prone to moderate drought will increase from 25 percent to nearly
50 percent by century's end. The 8 percent of the land now prone to severe drought
will increase to 40 percent of the land.
In any region where the climate becomes drier, forested areas also are likely to
shrink, with possible expansion of savanna, prairie, or even desert. A landscape
change of this magnitude is believed to have occurred in the New World tropics
during the Pleistocene glaciations. Due to the relatively dry climate at that time, what
are today continuous rainforests may have been constricted into relatively small,
isolated patches (refugia). These forest remnants may have existed within a landscape
matrix of savanna and grassland. Such an enormous restructuring of the character of
the tropical landscape must have had a tremendous effect on the multitude of rare
species that live in rainforests. Further, as forests shrink, precipitation decreases.
Trees transpire enormous quantities of water vapor into the air; without the forests,
entire regions experience dramatic declines in rainfall.
Climate change will also likely cause important changes in the ability of the
land to support crops. This would be particularly true of lands cultivated in regions
that are marginal in terms of rainfall and are vulnerable to drought and
desertification. For example, important crops such as wheat are grown in regions of
the western interior of North America that formerly supported natural shortgrass
prairie. It has been estimated that about 40 percent of this semiarid region, measuring
400 million hectares (988 million acres), has already been desertified by agricultural
activities and overgrazing, and crop-limiting droughts occur there sporadically. This
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climatic handicap can be partially managed by irrigation. However, there is a
shortage of water for irrigation, and this practice can cause its own environmental
problems, such as salinization of the soil. Clearly, substantial changes in climate
would place the present agricultural systems at great risk in many areas.
Patterns of wildfire would also be influenced by changes in precipitation
regimes. Based on climate model predictions, it has been suggested that there could
be a 50 percent increase in the area of forest annually burned in Canada, presently
about 1-2 million hectares (2.5-4.9 million acres) in typical years.
Shallow marine ecosystems also are affected by increases in sea surface
temperature. Corals are vulnerable to even very small rises in water temperature,
which deprives them of their symbiotic algae (called zooxanthellae). Depending on
the degree of warming, corals may be bleached or, if the warm-water regime is long
lasting, the corals may die. Widespread coral bleaching is increasingly observed as
oceans warm. Coral reefs are crucial in the life cycle of numerous fish species,
including fish many people use for food. The demise of coral reefs as sea surface
temperatures warm could devastate fisheries worldwide. A potentially more severe
problem for corals arises directly from increased atmospheric CO
2
, which increases
the acidity of the oceans as it dissolves. Increased acidity diminishes the ability of
corals and many other sea creatures with shells to make their hard parts of calcium
carbonate.
Extreme weather
Storms result from a complex number of factors, and it remains impossible to
attribute any single storm to climate change. However, the long-range prediction of a
number of climate models is for an increased frequency and severity of storms as
global temperatures rise. In August 2007, scientists at the World Meteorological
Organization, an agency of the United Nations, announced that during recent periods,
several regions of Earth showed significant increases above long term global
averages in both high temperatures and frequency of extreme weather events
including heavy rainfalls, cyclones, and wind storms.
A decrease in the temperature difference between the poles and the equator
would alter global wind patterns and storm tracks. Regions with marginal rainfall
levels could experience drought, making them uninhabitable. Overall, since warmer
air holds more moisture, an increase in global air and sea temperatures is expected to
increase the number of storms. Many climate models predict that higher sea surface
temperatures would increase the frequency and duration of hurricanes and El Niño
events.
Species migration and biodiversity loss
Studies of changes in vegetation during the warming climate that followed the
most recent Pleistocene glaciationsuggest that plant species responded in unique,
individualistic ways. These differences result from the varying tolerances of species
to changes in climate and other aspects of the environment, and their different
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abilities to colonize newly available habitats.
Some models predict that wild plant and animal species would need to move
poleward 100 to 150 kilometers (60 to 90 miles) or up in altitude 150 meters (500
feet) for each 1 degree Celsius rise in global temperature. As most species could not
migrate that rapidly, and as development would stop them from colonizing many new
areas, much biodiversity would be lost.
Modern drastic climate alterations could have more devastating effects on
ecosystems, and the plant communities at their base, because of the rapidity with
which these changes are occurring. The temperature and precipitation changes will
likely have an enormous impact on vegetation, as soil moisture drops in many parts
of the world. It is reasonable to predict that any large changes in patterns of
precipitation would result in fundamental reorganizations of vegetation in the
terrestrial landscape. However, unlike previous naturally induced changes in climate,
which usually occur over millennia, current climate changes may occur in a matter of
decades. Such abrupt changes leave plants, and the animals that depend on them, too
little time to adapt to the new conditions or to adapt enough to be able to survive in
other biomes.
Human populations also are predicted to shift due to climate change. Some
estimates suggest that the number of environmental refugees could rise to 150 million
by 2050.
Observable Climate Change Impacts
Studies conducted annually since 2000 have shown yearly decreases in both
the thickness and cover of Arctic sea ice. A study released in 2006 revealed that
perennial sea ice in the Arctic, normally 3 meters (10 feet) thick or greater, has
thinned to 0.3-2 meters (1-7 feet) thick. This thinner ice is far more vulnerable to
melting. Perennial ice cover also is declining rapidly, with a sharp 14 percent loss
between 2004 and 2005. This decrease represents an overall loss of 730,000 square
kilometers (280,000 square miles). Other studies conducted in 2006 considered the
extent of summer, or non-perennial, sea ice cover in the Arctic, which has been
monitored by satellite since 1979. The data show that sea ice extent reached record
lows in 2007 and 2012. The summer extent of sea ice was 39 percent lower in 2007
than the 1978-2001 average. The Northwest Passage, which is the sea route from the
Atlantic Ocean to the Pacific Ocean along the northern edge of North America, was
ice-free for the first time in recorded history. Some scientists predict that large,
navigable swaths of the Arctic Sea will be ice-free in summer by 2030.
One of the most dramatic signs of global warming is the rapid melting of most
of the world's mountain glaciers. In early 2008, scientists with the United Nations
Environment Programme announced that mountain glaciers were melting faster than
ever as a result of global climate change. The rate of melting more than doubled from
2004-2005 to 2005-2006 at thirty closely monitored reference glaciers around the
world. The melting rate for 2005-2006 was four times greater than that for 1980-
1999. Globally, not all glaciers thinned during 2005-2006, but the overall trend was
strongly toward accelerated melting.
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The year 2012 was the ninth warmest on record globally and the hottest year on
record in the United States. Despite the fact that part of the decade was spent at a
solar minimum, nine of the last thirteen years since 2000 have ranked in the top ten
for hottest average temperatures. In addition to 1998, every year after 2001 appears at
top of the warmest year record list.
In May 2013, carbon dioxide monitoring stations at the Mauna Loa
Observatory in Hawaii recorded CO
2
levels of 400 parts per million (ppm) for the
first time. Although CO
2
monitors recorded CO
2
levels of 400 ppm in the Arctic in
2012, the May 2013 results at Mauna Loa marked the first recording of CO
2
of 400
ppm or higher in a temperate zone.
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