Caroline Paulson
Earth Science
Current Events
3/21/15
University of Pennsylvania. "How rivers creep, flow to shape landscapes over time." ScienceDaily. ScienceDaily, 9 March 2015. <www.sciencedaily.com/releases/2015/03/150309174829.htm>.
How Rivers Creep, Flow to Shape Landscapes Over Time
Rivers exist all over Earth’s surface and have existed for a very long time. Rivers were present ever since the appearance of large bodies of water, such as the seven oceans that are on Earth today. Without the presence of water, life on earth would not exist, it would be a barren planet. While serving as a backbone of life, rivers also had a role in shaping Earth in its modern form.
The currents of rivers tend to erode landscapes, while in turn depositing whatever sediment they collected elsewhere. This movement over vast amounts of time can make a plain become a canyon. It is believed this can only occur, when there is high tide and the resulting force of the water only moves the particles found on the surface of the river bed. However a recent study gives another method of sediment transport, which includes, the force of the current and creeping-esque movements from beneath the surface due to particle interactions. This study was conducted by an associate professor at Pennsylvania's Department of Earth and Environmental Sciences, Douglas Jerolmack. Jerolmack, like other geologists, could not figure out why theoretical models depicting patterns of sediment transport in rivers, would never match up with actual observations. Those models utilized principles relating to physics, so it was hard to imagine what the issue was. Jerolmack stated, “Many people for a long time have assumed that the reason predicting particle erosion is hard is because there's turbulence and the flow force is fluctuating wildly.” Together with a physician, Durian, they started to speculate about what the issue could be, so they turned to the structure of the granular river bed.
To face the issue at hand, specialized experiments had to be conducted. Jerolmack hired Houssais and Ortiz who had a lot of knowledge about river transport and small-particle dynamics which relates to physics. The experiment consisted of an idealized depiction of a river, which was a doughnut shaped apparatus that was as big as a fish tank. The apparatus would rotate creating a false current, and dye would help track any particle movement. This does not sound all that different compared to most experiments conducted in classrooms, but in reality it’s probably a lot more complex than this. They tested multiple different flow rates and were able to conclude that there was another factor other than fluid dynamics that was involved. Jeromack and his companions were able to confirm that their suspicions that granular flow (the movement from particle interactions) did contribute to erosion. The implications of this could possibly foretell that the theory “threshold to motion”, is false. This theory states that as something slows to a stop, particle movement would vanish entirely - something untrue in terms of this experiment. However this experiment was staged within a lab, so it is hard to say if this is consistent in nature. Jerolmack states that, “We can't say anything about the level of creep in rivers because no one has ever measured it.” Although this can be taken as a sign of failure with respect to his results, he also states that, “However, the slow creep of soil down a hillside due to gravity is well known, and a next step is to examine whether the underlying physics are the same.”
While it may be easy to think indifferently towards river erosion, it still remains an important concept in modern times. In terms of social impacts it may have not left much of anything on society, but without any understanding of this idea, we would have never known of how the earth became what it is. Without rivers and the erosion that they cause, there would be no landscape for us to stand on, or even much of an Earth to live on. In terms of writing, this article was a little bit hard to follow. There was a lot of background explanations, while they helped, can distracting. The article also seems to be directed at people who already have some sort of knowledge about river erosion, which makes it difficult to understand. It also dwells partially off topic about the researchers involved as well as their thoughts. Generally this is not a bad thing, but in terms of appearances it looks very wordy. However ultimately, the article does meet the criteria for a piece of scientific writing creating an ambience of scientific expertise.
The review written by Caroline Paulson contained 3 aspects that were particularly well presented. The first aspect was the format of the review. This format was a type of essay style format, that helped the author organize their thoughts, and therefore increasing the ability of the reader to understand. The second aspect of the review that was especially well done was the use to quotes. When facts are backed up with direct quotes from the article, it proves to the reader that the author is legitimate, and it makes the piece of writing seem so much stronger. The third of the aspects that were particularly well done was the simplified explanations by the author of the original text. It seems based on the way the review is written, the original article must have been much more complicated. If the author chose to use the complicated facts instead of the ones that are much easier to understand, the review would make no sense to the reader and it would be very boring.
ReplyDeleteIn the article, there were 2 things that really impressed me. The first was that the scientists were able to make such a big discovery and challenge such a large and backed up theory. It must have been very difficult to stand against the crowd and challenge a logical idea. The second thing that really impressed me was the review author was able to understand and endure such an apparently tedious and complex scientific article.
The review could be better if it was shortened a tiny bit. The reason for this is because the review uses so many very complex ideas, it is easy for the reader to get confused and lost when too many are presented. The goal of the article is to maintain the interest of the reader throughout the article, which would be easier if it was shorter.
Hello Caroline, Niko here.
ReplyDeleteI liked this article that you wrote up. I watched a time lapse video of rivers being formed and fading out over years, they are very interesting and it's really amazing to see how fast rivers change. I agree with you that the main purpose of the author is to keep the reader "engaged" as opposed to providing quality astute analysis. I believe that the author did not express his points as well as he could have.
Caroline, you review was good. I like how you consistently inserted your opinion while sharing a good synopsis of the article.I look forward to further reviews!
Alexander Plaza
ReplyDeleteBlog Comment (Caroline Paulson)
Earth Science
4/12/15
Caroline, I thought that you did a good job on your current event. I like how you include specific details from the article in your paragraph. Your summary of the article is very thorough. This helps the reader gain a firm understanding of what the article is about and the reader can understand any references you might make to the article in later paragraphs. Also, you include many quotations of credible resources. By using quotes, you show your article has expert analysis proving the author and the article are legitimate. When your facts are backed up by expert analysis, it makes your review and article seem stronger and overall more scientific. Likewise, the way you wrote your review was easy to follow and you made a seemingly hard concept to grasp simple through your organization of facts. By making your review easy to follow, the review becomes more meaningful and interesting to the reader because the reader can easily make connections to life. There were two things that really impressed me about your article. First, I found it interesting that scientific models that were based on physics did not match up with actual observations. I found it interesting how scientists had a problem where it looked as if the laws of physics were wrong or their observations were wrong. Second, I found it interesting that the way rivers shape landscapes is very important to understanding how Earth was molded into what it is today. One thing I suggest you do to make your review better is shorten your summary so that you get to the main idea quicker. I feel like your summary could make readers stop reading before the connections and review are presented. I think you did a great job.
I think that Caroline did a particularly good job in presenting to the reader how important rivers truly are before getting to the recent study. She provided important background knowledge that I as the reader would find useful. Once she presented the recent research that had been done, she explained their experiments in a way that anyone could comprehend. Lastly she was able to critique the article and point out how it was well written, but with some flaws. She deconstructs what she thinks could have improved and what she thought was well done.
ReplyDeleteThis article gave me a better understanding on the role that rivers and erosions played in the development of earth as the planet we know of today. I also learned how these scientist test their theories multiple times and the process one goes through to achieve a conclusion.
I thought that the details of the article were very thorough and well constructed. Though the subject matter is complicated, I thought you did a good job in giving us context and explaining the thought process of the scientists during their research. I also found it interesting how at the time this article was written, the researchers had yet to reach an answer, and tests in nature still had to be done. That fact may make readers want to follow up on this story to see what the final result is. My only concern was the summary was a bit long compared to the opinion and I wish you would have analyzed the article a bit more from your point of view. Other than that this was an excellent review of the article.
I am commenting on Caroline's article "How rivers creep, flow to shape landscapes over time." Caroline did a very good job of presenting this article. One thing in particular that Caroline did well was that she did not repeat herself. When people repeat themselves, it often makes the article difficult to read and could lead to having to read through it multiple times in order to understand the article. Another thing that was done well was the incorporation of quotes in the article. Because specific quotes from the article were included, there was no doubt in my mind that the facts presented in the article were valid facts. Also, I thought that Caroline had a very informative and thorough summary of the article. I thought this was very impressive because I became very knowledgeable about the topic through reading Caroline's response and not the actual article.
ReplyDeleteThere were many new and interesting facts throughout Caroline's articles that caught my eye. However, two stood out among the rest. One of those facts was that scientific models that were based on physics did not match up with the actual observations. Another thing that impressed me was how knowledgeable Caroline became after reading this article. I feel like I could ask her any questions I would have and she could give me an answer on any!
Although Caroline's article is extremely good and well done, no article is without flaws. One thing I thought Caroline could have improved on was going more in depth with her own opinion. While she did a good job breaking down how the author wrote the article, she could have gone more in depth on her own opinion.