The image above which came from NASA's Jet Propulsion Laboratory shows the Earth.  The tiny little planet we live on.  In recent years a warming of Earth's average daily temperature has been seen in scientific datasets.  This increase in temperature if created by man, and not stopped could be devastating.  However, it is currently a topic of some debate as to weather this increase in temperature is man-made or a natural occurance.  As our Sun is the heat source for our planet the changes in its output are important to the temperature here.  If the Sun's output were to double the heat on Earth would make this planet uninhabitable.  With this in mind scientists here at The University of North Texas, and around the world are studying the problem to see if the increase in temperature is made by man, or is the result of some normal periodic fluctuation and will eventually become a cooling trend instead of a warming trend.  If this cycle ends up in a cooling trend that eventually leads to another ice-age, this problem could be just as bad for man-kind, so this problem deserves some attention.

It has been said by many people, throughout the world, that man is a product of his environment.  In recent history many world leaders, environmentalists, and people in the general population have become concerned with the idea that perhaps man is changing his environment.  This change may not be a beneficial one according to some researchers.  This change that has become of growing concern in the past decade is known as global warming.
 Global Warming can be defined as a general rise in the average surface temperature of the Earth.  In the movie industry it has even become the topic of some attention being called “a destructive trend second only to nuclear war.”  If man is responsible for this warming trend we could, in fact, be destroying our planet.

 This destruction would not come as a direct result of the increase in temperature but rather as a secondary cause of things that occurred due to the change in global surface temperature.  The chain of events would play out something along the following lines.  The first thing would be that the polar ice caps would begin melting more and more.  The melting of the polar ice caps would have all sorts of long-term effects on the Earth.  These effects would include but not be limited to:

· Raising of sea level
· Changing regional climate could alter forests, crop yields, and water supplies.
· Drastic effects of water supplies
· Threaten human health
· Harm birds, fish, many types of ecosystems
· Deserts may expand into existing rangeland
· More intense rainstorms
· Highly destructive weather patters (increase in El Nino, La Nina, tornadoes, and hurricanes)

It is known that energy from the sun drives the Earth’s weather and climate.  The Sun warms the Earth’s surface, which reflects energy that then gets radiated back out into space.  The Earth’s atmosphere, more specifically, some of the gases in Earth’s atmosphere trap some of this heat inside allowing life, as we know it to exist.  If some measure of global warming did not occur this planet would be uninhabitable.  The gases mostly responsible for the heat being maintained are water vapor, carbon dioxide, methane, and nitrous oxide.
It is known that the temperature has had fluctuations on the past.  There have been many times of heating and cooling in recorded history.  Civilizations have risen and fallen due to fluctuations in temperature.  Diseases can be seen to have had changes in prevalence along with the temperature.  Many different terrestrial effects can be seen based on what effects our global temperature has on the environment.   Temperature has been seen to be generally increasing since approximately the start of this century.  The following chart is a good display of this increase in global temperature:
   Figure 1:  Global Temperature Change over the past 120 years.
 

 The Environmental Protection Agency has stated that the Sun is the source of the Earth’s temperature.  It has also stated that the Earth’s temperature is on the rise.  What will be examined here is weather the natural solar cycle (discussed in detail in later sections) has any effect on what appears to be a natural temperature cycle.  More specifically does the increase in solar activity cause a long term increase in global temperature and might this increase in temperature actually go away naturally as the solar cycle starts to decrease in activity towards the next solar minimum.

IMPACTS OF CHANGES IN CLIMATE
 The impacts of climate change are extremely varied in nature.  They include the following:

· Health
· Destruction of bird life
· Agricultural effects
· Coastal zone changes
· Wetland shifts
· Changes in location and scope of desert lands
· Rangeland shrinking
· Forests being destroyed
· Polar regions changing
· Water table changes

In different parts of the world various diseases occur at different contagion rates.  There are in fact many different very serious life-threatening diseases that occur only in warmer climates.  Some of these diseases are not only life-threatening but can be spread from human to human very easily without the chance to be cured as some of the diseases that are more prevalent in warmer climates infect, and destroy human health very quickly.  The diseases of particular increased problems in warmer areas are those that are carried by insects.  Such diseases as malaria, yellow fever, and encephalitis would be of particular problem in areas they are almost never seen in currently.  Algae would start to affect areas it currently does not affect polluting water supplies.  The increase in algae would bring with it problems such as cholera.

Several effects of human life ending due to increase in temperature can be considered direct rather than indirect effects.  Heat exhaustion and certain respiratory problems occur at greater frequency.  The cardiovascular system of the human body must work harder on hot days to keep the body cool so people with heart problems become more susceptible to heart attacks during the hotter months.  If the temperatures of these hotter months were to increase or the numbers of hotter months were to increase the number of heart attacks would follow right along with it.

Ozone in the upper atmosphere blocks the harmful ultraviolet radiation coming from the Sun from reaching the surface of the Earth.  With higher temperatures globally also comes an increase in the amount of ozone at ground level globally.  Even though this ozone while it is high above us protects us from harmful ultraviolet radiation, while it is in the lower parts of the atmosphere it is a harmful pollutant.  This protective yet deadly gas damages lung tissues, causes increased problems and death rates among people with asthma, and causes an increase in people with other lung diseases having complications.  Even low levels of exposure to ozone can cause people with healthy lungs and bodies to experience chest pains and nausea.  According to the Environmental Protection Agency of the United States a warming of only four degrees could cause in increase of lower atmospheric ozone by approximately 5 percent.

Higher temperatures will also alter the life cycles of various bird species.  The loss of wetlands, beaches, and some of their more natural habitats would be one of the methods global warming had of reaching the bird population of the world.  If we take away the natural habitats of birds the world will become far less hospitable to their survival and more than likely will lead to the destruction of various species.  Certain bird species thrive in certain climates.  As a result of temperature continues to change in the upward direction many bird species would not be found as far south as they currently are due to their natural habitat being at lower average temperatures.
An increased level of greenhouse gases in the atmosphere could have some widely varies effects on the agricultural industry.  Levels of CO2 in the atmosphere alone could have some varied influences.  Just the change in temperature being generally upward could have a fairly positive effect on crop yields.  These temperature increases could lead to multiple growing seasons per year.  If the temperature increases too much, however, the influence would be negative rather than positive.  In some ways CO2 actually increases the rate at which photosynthesis occurs in plant life, thus increasing their growth rate.  However the Environmental Protection Agency (EPA) does warn that the initial increase is usually found to diminish over longer-term exposure of plant life to increased levels of CO2.  Another possible positive influence that increased CO2 would have on plant growth is that the increase in photosynthesis usually leads to an increased efficiency in water use of the plant.  These two factors combines would allow certain widely used agricultural products to actually increase in crop yields rather than decrease.  Unfortunately another by product of a general increase in temperature would be a lowering of ground water in most farming areas.  Even though the plants might be utilizing their water better, they may actually have less of it to utilize, which would lead to negative impacts.  More research is needed before it can be determined with any certainty what the outcome would be on the agricultural industry as a whole, however, it is certain that not all of the changes that would occur would necessarily be negative ones.  One of the biggest drawbacks would be in the increased need for artificial irrigation thus leading to overall higher consumer prices.

The EPA has also come forward along with several other research agencies and claimed that an increase in general sea level along the Gulf and Atlantic Coasts of the United States of one foot is likely by 2050 if global warming does not stop.  Rising sea level would have a number of negative impacts on parts of our environment.  It would lead to other low lying lands being covered in water, eroding beaches, intensifying flooding, a general increase in the salt levels of rivers, bays, and groundwater tables.  Coastal Marshes and swamps are of particular danger as their level is only a few feet different from Sea level.  The increasing of Sea level would result in an expansion of these Marsh and Swamplands.
Deserts are also likely to be impacted by any kind of global warming.
 

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