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Summary prepared by: Noor Salem and Wes SassProfessor Takle mainly focused on explaining the importance and usefulness of the Bretherton Earth System Science diagram. He mentioned that it is a very complicated diagram as it shows how a mathematical model can be arranged to incorporate applicable sciences such as chemistry, physics, biology and many other life sciences. The professor emphasized how the Bretherton diagram should help us acknowledge the fact that the represented cycles and balances interact and hence greatly influence each other.
Professor Takle also mentions that the Systems Theory views an "organism" in a holistic manner, which is different from the reductionist approach where components are studied individually and described by basic scientific concepts.
Dialog Summary
The dialog started with one student pointing out examples on the impact of alternative energy on the local and global climate. The student explained that there are important questions to be considered before an attempt to create a new policy and implement technology that deals with these energy alternatives. One of these interesting questions was what kind of environmental consequence would we face if vehicles were to be operated by hydrogen consuming engines. Since the only by-product of burning hydrogen is water vapor, how can this fact affect the environment? Another question was what global impact would result if we were totally dependent on solar energy as our main energy source. The student points out that there is a possibility that reflected and scattered radiation would be absorbed. It was also mentioned that major economic factors are to be taken into consideration when developing these previous ideas.
Another comment was posted regarding the negative effects of using alternative energy. Alternative energy is not always economically feasible especially for the use of wind and solar energy as well as hydropower. The student refers to a site to support her argument. She stated that not all renewable energy sources are created equal and that some are more economically and environmentally practical than others.
The referred site mentions brief examples of external disadvantages for the use of alternative energy. Wind powered mills, for example, produce a lot of noise. Drilling in areas that are considered as major geothermal heat sources can be dangerous as it introduces toxic emissions.
A different comment posted by another student was also about the impact of alternative energy on the global climate. The student used written reports and articles as her reference to support her reasoning. One report was said to discuss the prevalence of diesel engines and how it is important to reduce their use to improve environmental conditions. Alternatives for diesel fuel include natural gas, microturbines and fuel cells. Another article was also referred and recommended by the student.
The article discussed the advantages of using biodiesel fuel. This alternative fuel can reduce CO2 and NOx emissions to help with compliance with regulations.
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GLOBEC home page | |
| NASA Earth System Science Education | |
| Graedel, T. E., and Paul J. Crutzen, 1993: Atmospheric Change. An Earth System Perspective. W. H. Freeman and Co. New York, 446 pp. |