Global Climate Change – ESS Analysis
1.) H > L > E > A > B > E > H > A > E
Land use can affect climate in numerous ways,
however the human manipulation of earth’s surface
is the most direct influence. In the past few
centuries by cutting down forests through
deforestation and replacing them with pastures and
cropland, a larger amount of area has become
available to reflect the sun’s rays leading to an
increase in the reflection of incoming solar
radiation into earth’s atmosphere.
As energy from the sun passes through the
atmosphere, 26% is reflected back to space by
clouds and atmospheric particles, 19% is absorbed
Figure 1: Fate of solar radiation passing through Earth’s
by clouds, gases (ex. Ozone) and particles, and 4% is
atmosphere (Pidwirny, 2006)
reflected back to space by Earth’s surface. This
leaves 51% of the sun’s radiation actually being absorbed by Earth (Pidwirny, 2006) (see Figure 1). The
Earth’s surface then re-radiates the Sun’s energy as infrared radiation. Greenhouse gases in the
atmosphere then absorb this infrared radiation, and radiate the energy in all directions (Pidwirny, 2006).
This once again heats Earth’s surface, which once again re-radiates the infrared energy (see Figure 2).
Greenhouse gases include water vapor, carbon dioxide, and methane, and the warming cycle in which
these gases are involved is known as the Greenhouse Effect. The Greenhouse Effect is a naturally
occurring process without which life on this planet would not exist (EPA, 2009). Without greenhouse
gases in the atmosphere, the average temperature of the Earth would be 60 oF colder. This would drop
the average global temperature to about
0oF and render Earth uninhabitable to
life as we know it (EPA, 2009).
Human activities, however, have
increased the levels of greenhouse gases
in the atmosphere and augmented this
natural phenomenon. Due mainly to the
burning of fossil fuels, the concentration
of carbon dioxide in the atmosphere has
risen from about 280ppm in preindustrial times to 386ppm in 2008
(Hofmann, Butler, Tans, 2009). Farm
animals, especially cattle, and rice
paddies also release large amounts of
methane into the atmosphere (UCAR,
2007). Methane concentrations have
risen from 700 ppb in pre-industrial
times to 1775ppb in 2005 (IPCC, 2007)
(see Figure 3). Thanks to this amplified
Figure 2: The Greenhouse Effect
Greenhouse Effect, over the past century
average global temperature has risen 1.3oF and
will reach an increase of 3oF to 7oF by 2100 if
emission of greenhouse gases remain at the
current rates (EPA, 2009).
These rising global temperatures have lead to
greater rates of evaporation. Total column
water vapor has increased 4% since 1970, and
similar upward trends have been found in uppertroposphereic specific humidity (IPCC, 2007).
Water vapor is a powerful greenhouse gas, and
increased water vapor in the atmosphere due to
Figure 3: Atmospheric concentrations of carbon dioxide and
increased evaporation is part of a positive
methane (IPCC, 2007).
feedback cycle, as increased water vapor leads
to increased effects of global warming and greater evaporation (UCAR, 2007). Some scientists believe a
negative feedback loop is also possible, as increased evaporation could lead to greater cloud formation.
Greater presence of clouds would increase Earth’s albedo, decreasing the amount of solar radiation
reaching Earth’s surface via reflection (UCAR, 2007). In this negative-feedback model, increased
presence of low-altitude clouds would have a net cooling effect on the earth. Recent research,
however, lends more support to a positive-feedback cloud model. Data from the Pacific shows that with
increasing temperatures, water vapor rises higher into the atmosphere, thinning low-level clouds. These
thinner clouds are less able to reflect solar radiation, and allow more sunlight to reach Earth’s surface
(Clement et al, 2009). This positive feedback from increased water vapor in the atmosphere and thinner
clouds would further strengthen global warming.
References
Clement, A.C., Burgman, R., Norris, J.R. (2009) Observational and model evidence for positive low-level
cloud feedback. Science 325, 460-464.
Hofmann, D.J., Butler, J.H., Tans, P.P. (2009). A new look at atmospheric carbon dioxide. Atmospheric
Environment 43(12), 2084-2086
Intergovernmental Panel on Climate Change (IPCC). (2007). Changes in Atmospheric Constituents in
Radiative Forcing. Climate Change 2007: The Physical Science Basis. Cambridge University Press:
Cambridge, U.K.
Pidwirny, M. (2006). The Greenhouse Effect. Fundamentals of Physical Geography. Retrieved from
http://www.physicalgeography.net/fundamentals/7h.html
United States Environmental Protection Agency (EPA). (2009). Frequently asked questions about Global
Warming and Climate Change: Back to basics. Retrieved from
http://www.epa.gov/climatechange/downloads/Climate_Basics.pdf
University Corporation for Atmospheric Research (UCAR). (2007). Climate and global change. Windows
to the Universe. Retrieved from
http://www.windows.ucar.edu/tour/link=/earth/climate/climate.html
2.) L > E > A > E > B > H > B
Volcanic eruptions can enhance global warming by adding carbon dioxide into the atmosphere. The
small amount of global warming that comes from volcanic eruptions is offset by the far greater amount
of global cooling caused by the particles released into the stratosphere. This is called the haze effect
and can lower mean global temperatures. When a volcano erupts, water vapor in the atmosphere
combines with the sulfur released from the volcano and forms clouds of sulfuric acid. The droplets in
theses clouds can absorb solar radiation and disperse it back into space (like a mirror) and possibly lower
the temperature in the troposphere.
There are at least three volcanoes that show a relationship from their massive eruptions to years of cold
climate conditions that followed it. The first of this evidence is the 1815 eruption of Mt. Tambora in
Indonesia. The cold spring and summer that followed it became known as the “year without a summer.”
The United States and Europe were the worst hit, having snowfall in the summer and the advancement
of their alpine glaciers advancing to severely low elevations. The second example is of Krakatau which
erupted in Indonesia in August 1883. For several months after the eruption of Krakatau, the entire world
combated unseasonably cold weather and beautiful sunset and longer than usual twilight. The latter
two were due to the spread of aerosols spread thought the atmosphere, specifically in the stratosphere.
The last example is of the Mt. Pinatubo eruption in the Philippines in June 1991 which ejected 20 million
tons of sulfur dioxide and ash into the atmosphere that circled the earth for roughly three weeks.
According to Wolfe (2000) Volcanic eruptions of this magnitude can impact global climate, reducing the
amount of solar radiation reaching the Earth's surface, lowering temperatures in the troposphere, and
changing atmospheric circulation patterns.
When sunlight warms the ground or the ocean, the heat radiates in the air above it; as the warm air
rises, the air in the troposphere is “stirred up” as air pressure and density
are less at higher altitudes (Russell, 2009). Air is the warmest at the
bottom of the troposphere near ground level. As air moves away from
ground level, it becomes colder because an increase in altitude causes
lower temperatures. Although greenhouse gases such as water vapor,
carbon dioxide, and ozone naturally occurs in the atmosphere to keep the
Earth warm, the excess amount of such gases can cause an adverse effect
on our planet. As a result of excessive greenhouse gases in the
atmosphere, winter and summer temperatures can drastically increase
causing warmer weather, rainy winters, and extremely dry summers
because the gases trap the excessive heat in the atmosphere. Some
factors that influence the excessive amount of carbon dioxide in the
atmosphere are the burning of fossil fuels (coal, oil, and natural gas) and
the cutting down and burning of trees (www.ace.mmu.ac.uk/kids/globalwarming.html). Also,
chlorofluorocarbons (CFSs), which are ozone-destroying chemicals, are released into the atmosphere
through the use of hairspray cans, fridges, and making foam plastic. The adverse effect of CFSs is that
they are dangerous greenhouse gases because small amounts can trap large amounts of heat. Animals
and plants are affected by excess greenhouse gases. For example, polar bears are not as healthy as they
were twenty years ago and they are thinner because of the increase in Earth’s temperature causes the
melting of the ice which causes the loss of their home and food. Also, elephant seal pups are thinner
because their food is migrating to cooler waters.
(http://www.content4reprint.com/environment/global-warming-how-are-animals-affected-by-globalwarming.htm). As stated, “The warming of the atmosphere caused by greenhouse gases is melting
glaciers and causing ocean water to warm and expand thermally” (http://whyfiles.org/091beach/5.html)
because when liquids are heated, including the ocean water, it expands-takes up more space. As a
result, throughout the world, millions of people and areas of land will be at danger from flooding. Many
people will lose their homes and large areas of farmland will be ruined because of floods
(www.ace.mmu.ac.uk/kids/globalwarming.html).
References:
Russell, R. (2009). Windows to the Universe, at http://www.windows.ucar.edu/ at the University
Corporation for Atmospheric Research (UCAR): University of Michigan.
Wolfe, J (2000), Volcanoes and Climate Change. Retrieved
from http://earthobservatory.nasa.gov/Features/Volcano/
http://www.geology.sdsu.edu/how_volcanoes_work/climate_effects.html
http://www.sciencedaily.com/releases/2008/05/080512135102.htm
www.ace.mmu.ac.uk/kids/globalwarming.html
http://www.content4reprint.com/environment/global-warming-how-are-animals-affected-by-globalwarming.htm
3.) E > H > B > A > H >B > A > B > A > B > E > H
The biggest effect of global warming on earth is the
drastic rise in sea level due to the melting of glaciers
and ice sheets into the ocean. Recent research has
shown that the melting of Greenland’s’ ice sheet alone
may be the culprit for the roughly 25 percent rise in
sea level in the last 13 years. This rise will directly
affect the stability of our coastline. According to
Lovgren (2004), the complete melting of Greenland’s
ice sheets would raise sea levels an estimated twentythree feet. According to the nature Conservancy some
of the most at-risk ecosystems due to sea level rising
are mangroves. Mangroves with little sedimentation and on low relief islands are especially endanger.
Mangroves are especially important to the biosphere because they provide a habitat and nursery area
for many animals, and also produce oxygen through photosynthesis. In order to photosynthesize,
mangroves use sunlight, carbon dioxide and water to produce sugar. Though the process the
mangroves like all plants absorbs carbon dioxide and expels oxygen into the atmosphere. If the
mangroves die off, there will be less carbon dioxide absorbed, thus increasing the amount of carbon
dioxide emitted into the atmosphere. As stated earlier, the more carbon dioxide there is in the
atmosphere, the warmer global temperature will become.
As the global climate changes, plants often develop heat stress due to increased atmospheric
temperature. When plants are heat stressed, the temperature is so hot that it causes irreversible
damage to the plants’ function and or development (Anthony E. Hall). Heat stress not only can occur by
high day temperatures in the atmosphere but also high night temperature on these plants. “High
temperatures can increase the rate of reproductive development,
which shortens the time for photosynthesis to contribute to fruit or
seed production” (Anthony E. Hall). There is evidence of damage to
plants from both high day and high night temperatures. When
there is an increase in global climate, carbon dioxide increases in
the atmosphere and one of the outcomes is the amount of rainfall
being altered. These factors definitely impact the amount of food
produced and how well the plant will grow (ESPERE Association). If
there are not sufficient amounts of water the animals and plants in
the biosphere will die off.
References:
Environmental Science Published for Everybody Round the Earth (ESPERE)
http://www.atmosphere.mpg.de/enid/266.html
Hall, Anthony E. “Heat Stress and its Impact” University of California: Department of Botany and Plant
Sciences. http://www.plantstress.com/Articles/heat_i/heat_i.htm
Lovgren, S. (2004). Warming to Cause Catastrophic Rise in Sea Level. National Geographic News.
Retrieved from http://news.nationalgeographic.com/news/2004/04/0420_040420_earthday.html
http://www.eoearth.org/article/Sea-level_rise_and_coastal_stability_in_the_Arctic
http://www.sciencedaily.com/releases/2009/06/090612092741.htm
http://www.whoi.edu/seagrant/education/focalpoints/erosion.html
http://data.iucn.org/dbtw-wpd/edocs/2006-041.pdf
4.) B > L > A > E > B > H > L > E > L > H
According to the Environmental Literacy Council fossil fuels were formed over millions of years by the
decomposing remains of plants and animals under immense heat and pressure. This process resulted in
the natural fuels that we use for energy like coal, petroleum, and natural gas. Fossil fuels contain large
amounts of hydrocarbon and carbon. For over a century these three fossil fuels have generated most of
the energy consumed by our growing human population in the past century. In order to release the
energy stored in them, fossil fuels must be burned. Unfortunately it is during this process that a variety
of particulates like ash, nitrogen, carbon and sulfur dioxide, are released into the atmosphere. They can
combine with water vapor in the air to form compounds that form acid rain. The burning of fossil fuels
also releases carbon dioxide which many scientists believe are contributing to global climate change,
specifically global warming. The rise in atmospheric temperatures has
also increased the water temperature of the ocean. These changes in
oceanic temperatures have impacted coral reefs around the world.
Coral reefs are extremely complex ecosystems. They support almost 25 percent of all known marine
species in the world and are home to many plants, invertebrates and more than 4,000 species of fish.
Even though coral reefs grow best in shallow waters (70–85° ), It is possible for soft corals to grow in
places with warmer or colder water, but growth rates in these types of conditions are very slow. Despite
this, small but prolonged rises in sea temperature caused by global warming can cause coral to discard
their symbiotic food producing algae called zooxanthelle through a process called coral bleaching. Not
only are coral reefs a nursery area for fish and marine invertebrates, coral reefs act as storm buffers to
the coastline protecting it from wave action and erosion. When exposed to the climate, all minerals
have different rates of weathering especially when water is present. The weathering of minerals
especially carbonates, release more carbon dioxide into the atmosphere which has been proven to
increase global warming. The release of carbon dioxide though weathering of the lithosphere can also
increase the acidity of the ocean and can slow coral reef growth because it is made out of calcium
carbonate. Weathering of minerals can also progress the erosion of land and sedimentation in rivers.
References:
Reibeek, H., & Simmon, R. (2005). Paleoclimatology. Retrieved from
http://earthobservatory.nasa.gov/Features/Paleoclimatology/paleoclimatology_intro.php
http://www.aag.org/globalgeography/CGGE-MOD-GCC/cfpart3/cfpart332.html
http://news.nationalgeographic.com/news/2006/05/warming-coral.html
http://www.coral.org/resources/about_coral_reefs/coral_overview
http://oceanservice.noaa.gov/education/kits/corals/coral07_importance.html
http://www.enviroliteracy.org/subcategory.php/21.html
5.) B > E > A > L > H > B
Although some scientists disagree, the Intergovernmental Panel on Climate Change reported that the
accelerated warming of earth’s climate, a phenomenon called global warming, is “most likely” the result
of increased industrialization and the subsequent greenhouse gas emissions caused by human activity
(IPCC, 2007). Green house gases including water vapor, carbon dioxide, methane, nitrous oxide, and
ozone occur naturally and help keep the earth reasonably warm, however, the burning of fossil fuels and
deforestation have increased the amount of greenhouse gases thus increasing their effectiveness in
heating the earth. The more greenhouse gases, the more the planet is warmed, which creates a positive
feedback loop because the warmer the planet is, the more greenhouse gases, particularly water vapor,
will be created. This increased pattern of global warming has resulted in glacier loss in which the ice
melts into the sea, which then causes sea levels to rise. Additionally, the rapid acceleration of global
temperatures has accelerated the pace in which the snow-packed mountains and glaciers melt.
Therefore, there is less time for snow to accumulate on mountains and thus eventually there is less
water each spring. This could be especially devastating for people who live in the Southeastern United
States where according to the New York Times, over thirty million people depend upon the Colorado
River for water. Not only could this have an effect on human health directly it could also greatly affect
the areas agricultural production.
References:
Gertner, J (2007). The Future is Drying Up. New York Times Magazine. Retrieved from:
http://www.nytimes.com/2007/10/21/magazine/21water-t.html
Intergovernmental Panel on Climate Change (IPCC). (2007). Changes in Atmospheric Constituents in
Radiative Forcing. Climate Change 2007: The Physical Science Basis. Cambridge University Press:
Cambridge, U.K.
http://www.ipcc.ch/pdf/technical-papers/ccw/chapter1.pdf