Human kind has entered a brand new relationship with the earth. The constant and
increasing pressures we are exerting threaten our planets ability to sustain
life itself. Change-in the way we think , and in the way we live-is needed now.
Global warming is the most urgent environmental problem the world will face in
the next decade and the next century. Few, if any, trends are more important to
our future than climate change caused by human activities. Scientist around the
world are warning us that global warming poses a major threat to our future
quality of life, previously there has been little information on this problem.
Right now, the rate of global warming may be 100 times faster than it has ever
been. Very soon the earth may become hotter then at any time in human history.
In the last decades the problems of atmospheric change have been gravely
advanced by pollution resulting from human activities. These environmental
changes pose a real threat to the lives of people and wild life. It is vital to
all of us that we fully understand the complex relationship between the
atmosphere and the earth. The earth is getting warmer. the changes are small, so
far, but they are expected to grow and speed up. Within the next 50 to 100
years, the earth will continue to heat up hotter than it has been in the past
million years. as oceans warm and glaciers melt, land and cities along coasts
may be flooded. Heat and drought may cause forests to die and food crops to
fail. Global warming will effect weather everywhere, plants and animals
everywhere and people everywhere. Humans are warming the earth's atmosphere by
burning fuels, cutting down forests, and by taking part in other activities that
release certain heat- trapping gasses into the air. Humans all over the world
need to get together and solve these problems. In the southern hemisphere, the
warming is the greatest over Australia, southern south Africa, the southern tip
of south America, and the area of Antarctica near Australia. In the northern
hemisphere, warming is strongest in Alaska, northwest and eastern Canada, most
of the Soviet Union, and parts of Southern Asia, North Africa and south west
Europe. Climate has cooled in Great Britain and northern and eastern Europe. In
the USA scientists found no overall warming trend in weather records kept since
the nineteenth century, however keepin mind the United States covers only 1.5
percent of the earth's surface. As warming continues, every place on the earth
will be effected. In the frozen heart of the last ice age, 18,000 years ago, the
temperature was only about nine degrees Fahrenheit colder then today. So a
change of a few degrees can have a dramatic effects. Todays most sophisticated
climatic models estimate the global temperature will rise between 3 and 9
degrees Fahrenheit in the next century. This could occur as early as the year
2050. Here are the large scale changes the rise might bring: As water warms it
expands, taking up more space. So warmer ocean water, with added melt-water from
glaciers, will rise by twenty inches to five feet in the next 50 to 100 years.
Just a 1 foot rise in sea level can cause shorelines to recede a hundred feet,
and in flat terrain, a thousand feet. If ocean waters rise several feet, whole
beaches could wash away. Many homes, hotels, other buildings, and entire cities
will be threatened. Salt water will pollute freshwater wells that millions of
people use for drinking water. Coastal marshes, which are vital nurseries for
fish and other ocean life will be endangered. Along undeveloped coast, marshes
may survive because they can move inland with the rising waters. In many places
seawalls and other human structures will prevent this process and the marshes
will be destroyed. In the United States ocean water may cover the Florida Keys
and large parts of southern Florida and Louisiana. Two kinds of action are
called for. One is to take steps to prepare for the the effects of warming that
already have begun. Agricultural scientist must develop varieties of wheat and
other crops that can grow in a longer but drier growing season. Ways must be
fond to use irrigation water more effectively. Conservation will also be
important for drinking water supplies. Governments that control building and
other development along coasts must begin to plan for rising sea levels. In the
United States, billions of dollars have been spent to replace send eroded from
beaches, and to help ownersof beach front homes rebuild after storm damage. The
states of Maine and North Carolina now prohibit permanent buildings on
threatened beaches. PROFIT OR ENVIRONMENT? The petroleum industry is no
different than any other business. It exist to make money and will pursue any
means to profit. Americans and other people of the world don't realize how much
of an impact the petroleum industry has on the world economy. Most of us don't
think twice or even once at the gas pump about where our money is going. We just
grumble occasionally about the price, then pay and drive off until the tank hits
empty, requiring us to return. For the past century the petroleum industry and
the automobile industry have grown almost as one, industry dependent on each
other in the pursuit of profits. According to Ecarta 97, Petroleum has been in
use by man for centuries in the form of lubricants and medicinal products. The
past century has seen an explosion of petroleum exploration to feed the
combustion engine. The combustion engine is mainly used in the transportation
industry, primarily automobiles. This century old technology has grown to the
point where the world is dependent on the engine in daily living. Why does the
world continue to hang on to such old technology that is destroying our world?
The petroleum industry and automobile industry for years have believed that the
worlds oil reserves would never run out. Only during the past few decades have
the worlds industrial leaders realized that the world's supply of petroleum is
limited and that it is having an impact on the environment. Although
environmentalist with Environmental Protection Agency(EPA) have recognized the
problem, they have been slow to get strict standards passed through legislation.
The EPA has helped by mandating more efficient cars that use less fuel and
produce less pollution. The EPA and other agencies pushing for recycling
petroleum products and cleaner fuel have also temporally slowed the effects of
future shortages and pollution. But, we still haven't solved the main problem:
What can we use as an alternate power source that wont pollute the world? The
industry doesn't want to solve the problem. People are making billions of
dollars every year selling petroleum products that feed our transportation
industry. Everything from gasoline, lubricants, paints and plastics are made
from petroleum, and are used in our automobiles. In 1980 over 114 million
automobiles were reported to be on the road according to governmentstatistics.
Consumers continue to demand better and faster automobiles giving the industry
more of an excuse not to change and ignore the problem. Rumors over the years
have reported that the petroleum industry has kept new innovative products off
the market that could help reduce our problems considerably. They do this by
buying the copy rights or paying people not to produce the products. This can be
easily done by an industry that carries a big wallet. Advertising has also kept
the industry going. Advertisers portray a different picture that gets your mind
off the problem. Petroleum companies play on your automotive desires, like
gasoline that performs well and gives you more power. They also play on the
convenience of their stores by selling unrelated products such as groceries. The
industry has changed only to meet economic needs. The automobile industry has
also done little to comply with a growing attitude of change. With stricter
pollution standards hovering over combustion engines, they continue trying to
perfect hundred year old technology. The combustion engine just keeps being
refined enough to be in compliance with law. The fact is that we are still using
petroleum products in an industry that is growing by leaps and bounds all over
the world. The auto and petroleum industries will keep making minor adjustments
to address problems of pollution and dwindling resources. It wont be enough as
long as petroleum consumption continues to rise from millions of automobiles put
on the road each year. The advances we make to curb consumption and pollution
are offset by automobile industries desire to produce more and profit. These
dilemmas will persist as long as the auto and petroleum industries continue
making each other money. Fusion: Our Future's Energy? Fusion energy seems to be
the most promising energy source of the not-too-distant future. It is safe, it
uses an energy supply that is so abundant that it will never run out, it gives
off harmless waste, and it produces energy comparable to the Earth's sun! But
are there any problems with this hopeful energy source? What is Nuclear Fusion?
To understand fusion, it is a good idea to know about fission. This is the
splitting of the nuclei of atoms into two or more smaller nuclei by bombarding
them with neutrons of low energy. It was discovered in the 1930's in an attempt
to make transuranium elements (elements with atomic numbers greater than Uranium
that do not exist in nature). They discovered that the nucleus of Uranium-235
breaks apart into two smaller nuclei after absorbing a neutron. This happens
because the extra neutron made it unstable. This produces more neutrons that
bombard more Uranium nuclei, causing a chain reaction that produces an enormous
amount of energy. The problem is the nuclear waste that is produces. It is very
radioactive and will not become stable for a very long time. Such a harmful
substance is a great health concern and needs to be disposed of. Another problem
is the energy it needs. It uses an element that is hard to find and which will
eventually run out. Also, the reaction cannot be easily stopped and if it can't
be stopped, a nuclear meltdown can occur. This is a serious environmental
concern. Fusion is different. It is a process that combines two nuclei into one,
releasing an amount of energy that is far greater than that of fission. In a
common type of reaction, two isotopes of hydrogen, deuterium and tritium fuse
together, making helium and a neutron. A small amount of the mass produced is
converted into an enormous burst of energy. Difficulty of a fusion reaction The
main difficulty in a fusion reaction is the heat needed for it to occur. A
reaction such as fusion that requires an intense amount of heat is called a
thermonuclear reaction. It commonly takes place in huge machines called tokamaks.
It can only occur in a special form of matter called plasma, a gas made up of
free electrons and nuclei. When this plasma is heated millions of degrees, the
nuclei move so fast that they fuse. The problem is in finding a container that
can hold this extremely hot plasma. This plasma has a tendency to expand and
escape from its container. The walls of the container have to be very cool, or
else they will melt. If the plasma touches the walls, it becomes too cool for
the reaction to occur. But how can a container hold the plasma without touching
the plasma? The answer is in devices known as "magnetic bottles,"
which are twisted into coils. They have a metal wall that is surrounded by a
magnet. Electrical current flows through the magnet, creating a magnetic field
on the inside of the walls. This pushes the plasma away from the walls and
toward the center of each coil. There are problems with this reaction. All the
fusion devices built so far use more energy than they produce! Another problem
is the environmental concern. When neutrons bombard the walls of the reactors,
the walls become radioactive. Walls that become less radioactive will have to be
found. Why fusion is still half a century away The money needed to research
fusion is getting smaller and after about four decades of research, the payoff
seems to be far from now. The approach does not seem to be in the right
direction. Researchers have put too much emphasis on designing a practical
fusion power plant without really understanding some of the fundamental physics
involved. The experimental reactors have no general research purpose. The fusion
researchers will have to start rethinking their ideas. Research will have to
change from a developing a new energy technology to developing a broader
understanding of a fusion reaction. Alternatives to current reactors Some people
say that the current fusion reactors, such as the Tokamak Fusion Test Reactor at
Princeton University, should be shut down. But others say that these labs have
been very successful. The Princeton reactor can produce 10 million watts of
power in bursts of about a second each, but it relies on external power. These
reactions have not yet reached a point where the power produced in each reaction
can be used directly in the next reaction, allowing the external power to be
turned off. The Princeton lab wanted to build a new machine to replace the
current one, but the cost of 1.8 billion dollars and the unresolved technical
issues caused the idea to be rejected. Instead, the current machines continue to
be upgraded. A different reactor called the International Thermonuclear
Experimental Reactor, a next-generation tokamak, has also been proposed and
seems to be a better choice. Some people say that a new type of reactor, besides
the tokamak, should be used. The Japanese have a design called the Field
Reversed Configuration Reactor. Another idea is to use lasers to trigger fusion
in tiny pellets of fusion fuel. The goals of fusion An ideal fusion reactor of
the future could use the hydrogen extracted from one gallon of water to produce
the equivalent energy of 300 gallons of gasoline, eliminating the need for
fossil fuels. Everything should be automatic with very little supervision. It
should produce no harmful wastes and have no possibility of failure. But the
technical obstacles involved to make such a device are far from being completed.
Fusion will not become a commercial device until the second half of the next
century. However, one thing is evident: Fusion will eventually be the leading
source of energy for the future. Cloning Twenty years ago, scientists said that
cloning was completely impossible. But now, the science of cloning has come to
realization. Imagine meeting an exact replica of somebody. They look alike,
think alike, and even have the same genetic makeup. No, this isn't an episode of
Star Trek, this is reality. This is the new world of cloning, and thanks to a
7-month-old sheep named Dolly, a new science has been born. As with every new
science, there are those who believe in it, and those who oppose it. The new
technology of cloning should be utilized because it could bring back extinct
organisms, help infertile couples to have children, and potentially save many
lives. Cloning could bring back extinct animals. Over millions of years,
thousands of different species have gone extinct. Most were due to "natural
selection", while several others were due to human intervention. According
to the Encarta Encyclopedia, 1997, "nearly two-thirds of all the native
bird species and one-tenth of the native plants originally found on the Hawaiian
Islands have gone extinct recently. Most of these losses have been of species
unique to the Hawaiian archipelago. Predators, competitors, or diseases
introduced by humans from continental areas are responsible for many of the
extinctions. Many remaining species on oceanic islands are threatened or
endangered." With cloning, many of the animal species, and potentially
several of the plant species could be brought back to life. Even though there is
currently no technique for bringing the plants back, with technology advancing
so quickly, we could have a solution quite soon. Cloning, though now limited to
an! imal subjects, potentially has significant human applications. Cloning will
help a couple who would normally be unable to have children because one of them
was infertile. In the case of an infertile father, scientists take an egg from
the mother, remove its nucleus, then take a cell from the father, remove its
nucleus, and place the nucleus inside the empty egg. That cell now acts as a
reproductive cell. They then put the egg in the mothers' womb, and wait for
results. Unfortunately, this method has a very low success rate. According to
Gina Kolata of the New York Times, February 23, 1997, in the experiments with
the sheep, 277 cells were attempted. Twenty-nine of those developed into
embryos. When those cells were transferred to the female sheep, only thirteen
became pregnant. Of those thirteen, only one carried the pregnancy to full term
and delivered a live lamb. However, with the ever-progressing technology,
scientists will be able to achieve higher success rates. The power of cloning
can not only be used to create life, it ! can also be used to save it. Cloning
has many medical benefits that could be utilized. It could be used to replicate
organs from animals that would be suitable for transplant into humans. This
process would increase the amount of people who could be saved. Since there
would be more organs, the waiting lists for transplants would become much
shorter. According to James Glassman or the Denver Post, February26, 1997,
"Engineered animals like pigs could be cloned and harvested for organs to
transplant into sick humans". This would be much easier, because you don't
have to wait for an organ donor. Cloning can also recreate certain genetically
engineered animals that carry helpful substances. In the case of the sheep, the
main product that they are trying to get is AAT, a sheep's milk now in clinical
trials for use in treating cystic fibrosis.(CNN on-line, February 23, 1997)
Also, according to the Grolier Electronic Encyclopedia, 1992, "clones have
produced such medically important substances as Insu! lin, interferon, and
growth hormone". Due to the overwhelming positive implications, society
must embrace this new technology. The science of cloning should be used because
it could resurrect extinct animals, give couples a new hope, and medical science
now has a new tool that could potentially save thousands of lives. Cloning, once
the stuff of science fiction, will with recent advances become an integral part
of our society. To What Extent Does Acid Precipitation Affect Annelids? In order
to truly understand acid rain and it's eventual effect on earthworms, it would
be best to look at the causes of acid rain. How and why does altered acidity in
precipitation have a devastating effect? Acid rain is charecterized as
"Precipitation that has a pH lower than about 5.0" (Allaby, Michael
(1994) Ecology, Oxford Press,). Acid rain is created by many things, of which
pollution from cars contributes the most. Ever since the Industrial revolution,
the acidity of rain has been haywire. Sulfur and nitrogen are found widely
throughout the world in the air, "even in unindustrialized tropics" (Graedel,
Thomas, et. al, (1989, V261 n3 p. 58-68 Sep. 1989) The Changing Atmosphere,
Scientific American). The way in which acid rain is created from here is that
About 70 percent of acid rain comes from sulphur dioxide (SO2), which dissolves
into the water to form sulphuric acid. The rest comes from various oxides of
nitrogen (mainly NO2 and NO3, collectively called NOx). These gases are produced
almost entirely from burning fossil fuels, mainly in power satations and road
transport. (Kucera, (1973) The Challenge of Ecology, The Mosby Company.)
Tremendous quantities of this nitric acid and sulfuric acid mix are reflected in
the lowering of the acidity of rain. Earthworms (Annelids) are a species of worm
which are many segmented. They live in damp soil, usually forming intricate
tunnels beneath the surface. Their bodies are lond and cylindrical, and have
"bluntly tapered ends and are somewhat depressed posteriorly." (Storer,
et. al, (1972) General Zoology 5th ed., McGraw Hill Books.) As earthworms
burrow, thew swallow large quantities of earth that often contain large amounts
of vegetable remains, often depositing, or casting, their very nutritive remains
to the soil, which adds to it's enrichment. The first person to truly recognize
the importance of earthworms was Gilbert White, when he wrote in his book, The
Natural History of Selbourne (1788) that "soil was loosened, aerated, and
made more fertile by earthworms." (Gilber White (1788) The Natural History
of Selbourne) Earthworms are typically very sensitive to low pH levels.
Therefore, it isn't surprising that "pH of soil is sometimes a factor that
limits distribution, numbers, and species of earthworms." (Edwards and
Lofty (1977), Biology of Earthworms, Chapman and Hall) There have been many
experiments done on this, which indicate that earthworms prefer soils with a pH
of about 7.0. Some improtant workers include Arrhenius in 1921, Moore in 1922,
Phillips in 1923, and Petrov in 1946. All these studies concluded the above
stated fact, that worms prefer 7.0 However, in Denmark, Bornebusch found "Dendrobaena
octaedra, which is an acid-tolerant species" (Bornebusch, 1930) Studies
have also been conducted in Egypt, where it was found by El-Duweini and Ghabbour
that soil can also be "too alkaline to favour earthworms" (El-Duweini
and Ghabbour, 1956). In a study done by Satchell in 1955, in which earthworms
were placed in plots of soil with pH values ranging from 4-7, the worms in soils
with the higher acidities were "jerking and convulsing........after 1 to 2
hours became motionless and flaccid. After 24 hours, fifty-eight out of sixty
worms exposed to pH below 4.4 were dead." (Edwards and Lofty, (1977)
Biology of Earthworms, Chapman and Hall) Earthworms are easily used for
experimentation by researchers because they are "widely distributed,
familiar organisms, which are readily and cheaply available in large
numbers." (Pierce, et. al, (Sep, 1988 Volume 70) Science Notes, School
Science Review.) In soils of pH less than 5, earthworms are usually scarce, and
soil breakdown is usually slow, making a "deep layer of slowly decomposing
plant remains." (Pierce, et. al, (Sep, 1988 Volume 70) Science Notes,
School Science Review.) This is a very obvious sign of wether or not earthworms
are present, and more often than not, the pH range can be determined on sight.
If you look through soil and see plant material broken down and mixed through
the soil, you know that earthworms are there and are playing a major role in
soil breakdown and nutrition. The Greenhouse Effect The greenhouse effect is an
increase in the atmospheric temperature caused by increasing amounts of
greenhouse gases. These gases act as a heat blanket insulating the Earth's
surface absorbing and trapping heat radiation which normally escapes from the
earth. They include carbon dioxide, water vapor, methane, nitrous oxide, CFC's,
and other halocarbons. The earth's atmosphere goes through two processes
constantly. Global cooling is the first process. This process uses the clouds
which cover 60% of the earth's surface to reflect 30% of the solar radiation. It
also uses a sulfate haze, which is formed by sulfur dioxide from industrial
sources that enter the atmosphere and react with compounds to form a high-level
aerosol. These cool the atmosphere by blocking us from direct contact with the
sun. The reflection of the sunlight is referred to as planetary albedo and
contributes to the overall cooling. The second is the warming process. This is
when light energy comes through the atmosphere and is absorbed by Earth and
transformed to heat energy at the planet's surface. The infrared heat energy
then radiates upward into space. There the greenhouse gases found naturally in
the troposphere absorb some of the infrared radiation. The gases insulate the
Earth, but do eventually allow the heat to escape. Without these greenhouse
gases the earth would be would 33 C colder. Global temperature is a balance of
the effects of the factors leading to global cooling, and warming.
Unfortunately, increased emissions of greenhouse gases increase the warming
process. For example, every kilogram of fossil fuels burned equals 3 kilograms
of carbon dioxide ( the mass triples because each carbon atom in fuel bond to
two oxygen atoms, in the course of burning, and forms C02. ) 6 billion tons of
fossil fuel carbon are burned each year adding 18 billion tons of C02 to the
atmosphere. This has increase the carbon dioxide concentrations by 25% and has
cause temperatures to increase more than 0.7 C over the last hundred years. We
hope that the forests will act as a sink for carbon dioxide but instead they are
a net source. This is because the forests are being cut and burned adding 1 to 2
billion tons annually to the 6 billion tons of carbon already from industrial
processes. Fortunately, the top 300 meters of oceans absorb most of the carbon
dioxide emitted by burning fossil fuels. Other factors are known to increase the
greenhouse effect. These factor are water vapor, methane, nitrous oxide, CFC's
and other halocarbons. Water vapor is also a major factor in what has been
called the "supergreenhouse effect" in the tropical Pacific ocean.
Water vapor traps energy that has been radiated back to the atmosphere. The high
concentration of H2O vapor contributes significantly to the heating of the ocean
surface and lower atmosphere in the tropical Pacific. Methane (CH4) is a product
of microbial fermentative reactions and is also emitted from coal mines, gas
pipelines, and oil wells. Methane is gradually destroyed, but it is added to the
atmosphere faster than it can be broken down. Methane (CH4) is a product of
microbial fermentative reactions and is also emitted from coal mines, gas
pipelines, and oil wells. Methane is gradually destroyed, but it is added to the
atmosphere faster than it can be broken down. Nitrous oxide (N2O) can be found
in biomass burning, chemical fertilizers, and fossil fuel burning. Nitrous oxide
is more dangerous than some of the others because of its long residence time of
170 years. CFC's and other halocarbons are found in refrigerants, solvents, and
fire retardants. Halocarbons have a greater capacity, 10 000 times, for
absorbing infrared radiation, which is about 60% more, than CO2. Although there
is increase in the application of some of these gases, they will decrease in
importance in the future leaving carbon dioxide as the primary dilemma. In 1981,
James Hansen of NASA invented a model with an ability to track known temperature
changes and link them to past and future carbon dioxide levels as well as global
temperature changes. The model suggested the combination of CO2 and volcanic
emissions was responsible for most of the observed changes in temperature during
the 1980's. A trend of warming of more than 0.7 C coincides with an increase of
25% in carbon dioxide. Two major impacts of greenhouse effect are regional
climatic changes and a rise in sea levels. A climactic change will lead to
variations in temperature. Scientists expect more precipitation which may prove
to be disastrous for North America by flooding rivers and lakes. A rise in the
sea levels is anticipated because of an increase in thermal expansion and the
melting of ice caps and ice fields. Like extensive rainfalls, a rise in the
ocean will flood lakes and rivers covering land and may someday bury continents.
In order to control the effects of global warming we must first admit that it's
occurring, then take steps to end it. We must stop burning the trees and not
replacing them. Most importantly, we must stop polluting the air.