Global Warming Homework

I recently had to write a paper for homework. Yes engineers write too! It's a bit long, but I thought it was interesting so I included it below. It's a bit on the long side so I won't be offended if you don't read it. But, feel free to read it anyway.

-----------------Global Warming Contributors and Validity----------------

There are many controversial topics within the overreaching dome of modern science. Among the most controversial lies the topic of global warming, and its validity. Global warming is defined, by Wikipedia, as the increase in the average temperature of near-surface air and oceans since the mid twentieth century. Global warming also states that the increase in average temperatures on earth is a result of man’s contribution to the green house effect via the large volume of green house gases that are artificially put into the atmosphere.

Green house gases are a necessary part of earth’s ecosystem. Without GHGs earth’s temperature would be approximately thirty degrees celsius lower than what it is at present. The major contributors to the green house effect are water vapor, carbon dioxide (CO2), Nitrous Oxide (NO2) and Methane. They have separate atmospheric lifetimes which are respectively, 9 days, 1004 years, 1144 years and 124 years.

The major greenhouse gases created by humans include CO2, Methane and NO2. Of the one hundred percent of total GHGs, CO2 has climbed to 72% of the total volume. NO2 has reached a level of 9% of the total volume of GHGs. And, methane has attained a level of 18% of the total volume.

Since the industrial revolution there has been a sharp rise in the total volume of the major green house gases present in our atmosphere. Over preindustrial 1750, there has been a 38% increase in the total amount of CO2 in the atmosphere. Similarly, there has been a 67% increase in the total volume of methane present in the atmosphere. And, likewise there has been a 16% increase in the total volume of NO2 in the atmosphere. Major contributors to the increase are attributed to power production plants (such as coal plants), factories, and automobiles.

While debate on the topic of global warming threatens to continue indefinitely one detail remains evident. The green house effect is a part of our climate. And, when the effect is changed by human activity, the change must be evaluated by climate models. Climate models are defined, by Wikipedia, as models that use quantitative methods in order to simulate the interactions of atmosphere, oceans, land surface and ice.

Climate models take into account the total amount of energy that is either leaving or entering the system. Any surplus energy will inevitably lead to an increase in temperature, among other results. Conversely, a deficit of energy will eventually lead to a decrease in temperature of the system, along with other results. These complex analyses are multivariable having multiple inputs. For example a global climate change model would have many inputs. Some examples of these inputs would include cloud cover, total volume of atmospheric gases, total light energy from entering from the sun, gravitational energy from surrounding bodies, rate of increase of GHGs and many others.

The green house effect clearly exists and it is evident that humans have been increasing the amount of gases that are involved in the green house effect. However there is a widespread debate on wither global warming is a product of man’s misuse of natural resources or of pure imagination. On one side of the debate there are scientists and supporters who state that there measureable changes in the atmosphere that are a chemical result of the increased presence of certain GHGs. On the other side of the debate are scientists and supporters who state that the increase in global temperature is a direct result of cyclical trends. They state that these trends have occurred since the formation of earth’s atmosphere and will continue to heat and cool as time progresses indifferent to human intervention.

In order to determine wither or not there man is having significant impacts on the green house effect, evidence must be evaluated. One such piece of evidence states that global near-surface air temperature has increased by 1.33 ± 0.32 °F, in the last century. Climate models predict that within the 21st century temperatures will increase by 1.33 ± 0.32 °F. There is also evidence that proves that the polar ice caps are decreasing in size. Ice caps, located under low ozone zones, have shrunk by 57% in the last four years, decreasing thickness by 2.2 feet. As temperature increases so does the probability of more intense droughts, heat waves and hurricanes; as seen in 2004-2005.

The idea of global warming is such that an increase in temperature will cause irreparable, negative changes to our environment. It is evident that CO2, Methane and NO2 increase the green house effect. It is also clear that humans have dramatically increased the volume of these gases in the atmosphere, recently. This information coupled with negative effects, such as shrinking ice caps, climate sensitivity, more intense hurricanes and higher impact forest fires shows that global warming does exist and is having immediate consequences.

Even though global warming is manifesting itself with new vigor every year, this is not to say that both sides of the argument do not have valid points. There may well be a cyclical process by which the earth increases and decreases in temperature. However, this does not disprove the fact that if the habits of humans do not change dramatically, the point about which the temperature cycle oscillates may increase to a point that no longer supports normal life on earth.

Sources:
1. http://en.wikipedia.org/wiki/Global_warming_controversy
2. http://cdiac.ornl.gov/pns/current_ghg.html
3. http://en.wikipedia.org/wiki/Climate_model
4. http://en.wikipedia.org/wiki/Greenhouse_gas#Anthropogenic_greenhouse_gases