(After a lot of reading and hunting around on the net, I found a great deal of
information on this topic. I had never really researched on it before so wanted
to make sure that calculations agreed from report to report. Most of them did so
I will base my answer on these different reports. This subject is extremely
interesting, scary and a bit of a shock as to how much we have abused and taken
advantage of this Earth. Though progress as far as technology has been something
we make use of and enjoy, we are paying for it in ways I never thought of before
this subject came up in this class! Please forgive my ignorance. I am troubled
that my children and their children will suffer because of our lack of concern,
knowledge and greed. I read a short story the other day, about the people in a
village having never heard the word cancer until they were run out of their
homes and into the city area's. Years later, some of the people from this
village are dying from disease. my point is that before they came to the cities,
they had always died of old age ...) FIRST of all, it is important to know that
the "greenhouse effect" is not a bad thing in itself. In fact, this
planet would be a life-less waste land without its natural greenhouseing. There
are a collection of gases called "greenhouse gases," which are water
vapor, carbine dioxide, ozone, methane, nitrous oxide, and chlorofluorocarbons
(CFC). Without the natural greenhouse effect, the surface temperature of our
planet would be an average of -18°C (zero degrees F). The mixture of these
gases have remained pretty much stable over the centuries and have kept us all
living. But here we are in the late nineties, and we are not so stable anymore.
Our activities and what we use to perform our activities is increasing year to
year, many of them doubling and tripling. It's a case of the amount of gases
that Earth produces naturally vs. the amount of gases produced manually by us.
Do you drive? How about using those disposable diapers that NEVER disintegrate?
Do you smoke? How about garbage or junk burning? Do you BBQ? Where do you work?
Do you have an air-conditioner? Do you separate your garbage, use hair spray,
spray deodorant, spray paint, flea spray, perfume, kitchen spray cleaner, bleach
in your laundry, bleach in your hair, use a freezer, use an air conditioner in
your car, use your fireplace, have a growing collection of newspaper and
magazines, throw away food, use paper and plastic food containers, use bug
spray, use lawn pesticides, ... Okay, this could go on forever. The effects of
the huge overuse of these items of luxury plus all the other unmentioned items
and activities plays havoc on our atmosphere. We didn't worry about this 100
years ago, and the industrial revolution is the culprit for a large part of
this. The reason for this is a little thing called Carbon dioxide. Where is the
C02 coming from? Fossil fuel burning (75%), land clearing & burning (25%) ,
as well as car exhaust and coal burning. This stuff stays in the atmosphere for
50-200 years. Here is how it works. The chemical makeup of our atmosphere and
ozone is very complex. It is a combination, and interaction of the ocean, sun,
land, and the biosphere. The greenhouse gases work to trap the heat producing
energy on our Earth, and pretty much does a good job of it if left undisturbed.
We have disturbed it. The human production of greenhouse gas producing chemicals
is what is disturbing it. This production by humans of these particular gases
linger in our atmosphere for many many years and they burn up our protective
ozone blanket faster than it can rebuild itself. Our ozone blocks out most of
the killer radiation rays from our sun. Ozone is a molecule with just three
Oxygen atoms. It is created when UV light reacts with oxygen gas, which has two
Oxygen atoms. UV light also destroys ozone, so you need just the right mix of UV
light and oxygen to get an ozone layer. For the last 450 million years, our
ozone has been our sun screen. Chemicals that we use in daily life produce ozone
eating atoms when they reach the stratosphere and are exposed to intense UV
rays. Chemicals such as CFC's are too unreactive to be removed and they rise
slowly, taking 10-20 years to make the journey up to the stratosphere. Once
there, the high UV rays breaks down the atoms into chlorine atoms which speeds
up the breakdown of ozone (O3) into O2 and O . Each of these molecules last from
65-110 years and each one can convert up to 100,000 molecules of O3 to O2. These
guys in turn, are the ozone terminators., and they are not even the only ones.
Over Antarctica there is a gaping ozone hole measuring about three of our
continental U.S. in size. What has happened is during their sunless winter,
winds blow steadily in a circular pattern over the earth's poles, which creates
huge swirling masses of ice-cold air that gets trapped above the poles. When the
sun returns a few months later the water droplets in the clouds enter these
large circling streams of icy air and form tiny crystals. The surfaces of the
crystals collect ozone depleting chemicals in the stratosphere which allows them
to deplete the ozone layer at a much faster rate. The return of the sunlight
triggers weeks of ozone depletion before vortex breaks apart. THEN, masses of
ozone-depleted air flow northward and linger for weeks above Australia and New
Zealand, raising the UV levels in these areas by as much as 20%... and guess
what? They have had a HUGE rise in skin cancer. This very thing is also
happening over parts of North America, Asia and Europe. So, what would global
warming do to us? (as in, do I really need to worry about this???) Well, to put
it bluntly, it eventually would kill you and everything else that is alive. The
rise of a few degrees doesn't seem like a big deal, but in global terms... it is
deadly. It isn't just the rise of surface temperature, it is the pollution from
the over production of the greenhouse gases as well. By the year 2020, over
700,000 deaths worldwide will occur annually from exposure to particles as a
result of fossil-fuel burning that could be avoided by a climate control policy.
New animal and human studies confirm that airborne fine particles can sicken or
kill people. For example, laboratory rats with respiratory disorders died after
being exposed to air pollution at concentrations found today in Massachusetts.
Today our atmosphere contains 28% more carbon dioxide than it did 100 years ago,
and that percentage is rising drastically. Some of the warning signs that have
already taken place are: Surface temps at nine stations north of the Arctic
circle have risen by about 9 degrees F., since 1968. That is almost half a
degree a year. The thick massive ice shelves surrounding the continent in
Antarctica are beginning to break up. We had a huge one the size of a state
break up just recently. Winter snow in the northern hemisphere has been
decreasing every year, in fact, I have heard it said that Washington state will
someday have southern California weather. Since 1980 the average water temp. in
Alaska's Toolik lake has increased by about 3 degrees. The surrounding tundra is
beginning to thaw which could accelerate global warming by releasing massive
carbon dioxide and methane from these soils. Future implications could cause a
change in where food can and can't grow. Drops of only 10% in global crop yields
would lead to large increases in hunger and starvation. Wild fires would
increase, in up to 90% of North American forests. This certainly would not help
in reducing the carbon dioxide in the atmosphere. Climate change would lead to
reductions in bio diversity. This leads to ecosystems that can not adapt. The
rise in sea level would cause massive flooding. Even a rise of one foot would be
disastrous. Global warming poses an unprecedented threat to our environment and
our economy. Climate change can cause a spread in the ranges of tropical
diseases (Dengue fever, a painful life-threatening disease endemic to tropical
regions, broke out on the Texas border in the fall of 1995), intensified storms,
mass extinction of plant and animal species, and crop failures in many
vulnerable regions. Deserts may expand into existing rangelands, and the
character of some of our National Parks may be permanently altered.
Unfortunately, many of the potentially most important impacts depend upon
whether rainfall increases or decrease, which can not be reliably projected for
specific areas. We certainly still do not know enough. There are disagreements
all around, and the cost plus the emission of the ozone killers that are
produced, trying to cut down on the ozone killers, is a problem in itself. This
is a bit disappointing, the fact that we all will most likely be dead by the
time there is really any significant change... but our kids and their kids will
still be here.... Thats another thing... the population problem....