Ananthaswamy states in the secondary article that phytoplankton in our oceans encourage the occurrence of tropical storms. The reason for this is that these microscopic plants account for the lighter, murky shades of blue in some regions of the ocean. When there is not as much plankton in the ocean, the water is observed to be clearer with a deeper shade of blue. It is predicted in this article that as atmospheric temperatures from climate change have been rising, the number of phytoplankton have been declining. This consequently accounts for the clearer ocean water and the drop in hurricanes on American and Asian coastlines. When the absence of plankton clears up the murky waters, heat from the sunlight is able to penetrate deeper into the ocean. This warm water is swept away in the undercurrent, making the surface cooler. Gnanadesikan explains the meteorology involved in the primary article, which Ananthaswamy seems to leave out. With a cooler ocean surface, energy is no longer provided from the heat and the air circulation patterns then change. The dry air resulting from this prevents thunderstorms from growing into hurricanes. The secondary source does in fact have more detail about these gyres in the ocean. Gyres are systems of rotating currents and Ananthaswamy describes that the centre allows for light to penetrate the water to 100 metres. This part of the gyre is much clearer than the outer edge, so here light can only penetrate up to 10 metres. This shows that with less plankton in the ocean, the waters become a clear blue; heat can then travel deeper, changing the wind patterns and preventing tropical storms.
While reading Gnanadesikan’s article, there is much more detail used in the explanations of these processes occurring, and it is backed up by additional results observed from various experiments. He and his team describe chlorophyll’s role very effectively in this natural occurrence. “We think of the oceans as blue, but the oceans aren’t really blue, they’re actually a sort of greenish color,” said Gnanadesikan. The reason for this is said to be from the chlorophyll content in the ocean. Chlorophyll is a green-coloured pigment in plants used to convert energy from the sun into food through the process of photosynthesis. This explains how an absence or decrease in phytoplankton eliminates the chlorophyll content in the ocean, clearing up the colour of the water and allowing sunlight to penetrate much deeper. Gnanadesikan’s team lead an experiment with two scenarios. One included normal amounts of chlorophyll and the other with no chlorophyll present in the water. With an absence of this green pigment, a 70 percent decrease in hurricanes was observed in the north Pacific. Ananthaswamy gives a brief overview of the results in this experiment, but not nearly enough detail for the reader to fully grasp the ideas. He does state the main point that a clearer gyre will account for less hurricanes, although he does not describe how the first test was done with normal chlorophyll levels in the ocean. Nor does he explain to those readers unaware of plant biology what chlorophyll is and how it is the ultimate cause of murky waters. In the secondary article, he states that the first experiment was performed with half the normal chlorophyll levels, which is incorrect information, as the primary source clearly states that it was done with normal concentrations. This picture represents the amount of chlorophyll in the Pacific ocean. The darker blue regions represent the areas with lower concentrations.
The purpose of an author writing an article or essay based on another piece of work is to make it their own; they give their own ideas, opinions, and possibly include further research. These writers must give proper information from their primary sources and be sure to avoid changing facts written by another person. In these specific examples about hurricanes being affected by ocean colour, the secondary article gives a general overview of the science involved in the experiments and information presented by the original source. This may be an appropriate piece of writing for readers without a science background, but the first article contains the detail required to fully understand these ideas and findings. Ananthaswamy seems to focus on the plankton that prevents the oceans from being a clear blue, while Gnanadesikan explains that this is caused specifically by the chlorophyll used by plankton. It should always be kept in mind that when reading an article, this is but one source and one point of view.
Works Cited
Ananthaswamy, A. (August 2010). Deep blue oceans spawn fewer tropical storms. NewScientist. Retrieved from http://www.newscientist.com/article/dn19319-deep-blue-oceans-spawn-fewer-tropical-storms.html
Works Cited
Ananthaswamy, A. (August 2010). Deep blue oceans spawn fewer tropical storms. NewScientist. Retrieved from http://www.newscientist.com/article/dn19319-deep-blue-oceans-spawn-fewer-tropical-storms.html
Gnanadesikan, A., et al. (August 2010). Ocean’s Color Affects Hurricane Paths. American Geophysical Union. Retrieved from http://www.agu.org/news/press/pr_archives/2010/2010-25.shtml
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