Argument47 【Persistence小组】第10次作业

iamstoicUID: 2294314

Scientists studying historical weather patterns have discovered that in the mid-sixth century, Earth suddenly became significantly cooler. Although few historical records survive from that time, some accounts found both in Asia and Europe mention a dimming of the sun and extremely cold temperatures. Either a huge volcanic eruption or a large meteorite colliding with Earth could have created a large dust cloud throughout Earth's atmosphere that would have been capable of blocking enough sunlight to lower global temperatures significantly. A large meteorite collision, however, would probably create a sudden bright flash of light, and no extant historical records of the time mention such a flash. Some surviving Asian historical records of the time, however, mention a loud boom that would be consistent with a volcanic eruption. Therefore, the cooling was probably caused by a volcanic eruption.

In this argument, the author concludes that the extremely cold temperatures of Earth in the mid-sixth century were probably caused by a volcanic eruption. To support this claim, the author point out that some documents found both in Asia and Europe mention a dimming of the sun either due to a meteorite collision with Earth or a volcanic eruption. In addition, the arguer reasons that a large meteorite collision was not responsible for the cooling since no surviving accounts mention a flash that collision would probably create, and some extant Asian records indicate a loud boom which would be associated with a volcanic eruption. This argument seems logical at first glance but is problematic for several reasons after a careful examination.

First of all, the author unfairly assumes that a dimming of the sun mentioned in some historical accounts of Asia and Europe is the cause of the extremely freezing temperatures. However, he/she fails to rule out other possibilities for the cooling. It is entirely possible that Earth suddenly became significantly cooler before the sunlight was blocked by a large dust cloud. It also might be the case that the darkening of the sun did not happen in other areas except Asia and Europe. For that matter, the dimming of the sun only in some parts of Earth was probably not capable of lowering global temperatures. Without taking into account such possibilities, the author cannot arrive at the conclusion based on this assumption that global temperatures declining significantly were attributed to the dimming of the sun mentioned in the documentation.

Even if one accepts this assumption, the argument is also weakened by the fact that it does not consider the possibility that a large meteorite collision may happen at that point. There are no records mentioning the bright flash of light caused by a large meteorite collision but it does not necessarily follow that the collision did not come to pass. Perhaps it occurred in a desolate place and no individual can possibly know and hence record this event. Or perhaps the recordings concerned were lost due to some natural disasters. Thus, the mere fact that “no extant historical records of the time mention such a flash” lends scant support to the author’s conclusion.

Furthermore, there is no evidence provided that the loud boom mentioned in some Asian records at that time was just due to a volcanic eruption. The author overlooks the likelihood that the loud boom was resulted from a thunder in a storm rather than the eruption of a volcano. The recorder is likely to record the loud boom taking place in a thunderstorm and fails to write down the flash of light coming about at the same time. In short, since the author has not ruled out all other possible scenarios that might serve to bring about a loud storm, I simply cannot take the conclusion seriously.

Finally, the author’s conclusion rests on the postulation that the dimming of the sun has only two alternatives. In all likelihood, Earth was screened from direct sunlight by some gigantic planet that passed between Earth and Sun. Thus, the author’s claim may mask other causes of the dimming, which may render the conclusion unwarranted.

In conclusion, the argument could be improved by providing evidence that it is a large dust cloud throughout Earth’s atmosphere which blocked sufficient sunlight that lowered global temperatures considerably. It could be further improved by ruling out other possibilities and alternative explanations for dimming the sunlight.


[ 本帖最后由 iamstoic 于 2007-2-10 19:59 编辑 ]

Andy85UID: 2250503

In this argument, the author concludes that the extremely cold temperatures of Earth in the mid-sixth century were probably caused by a volcanic eruption. To support this claim, the author points out that some documents found both in Asia and Europe mention a dimming of the sun either due to a meteorite collision with Earth or a volcanic eruption. In addition, the arguer reasons that a large meteorite collision was not responsible for the cooling since no surviving accounts mention a flash that collision would probably create, and some extant Asian records indicate a loud boom which would be associated with a volcanic eruption. This argument seems logical at first glance but is problematic for several reasons after a careful examination.

First of all, the author unfairly assumes that a dimming of the sun mentioned in some historical accounts of Asia and Europe is the cause of the extremely freezing temperatures. However, he/she fails to rule out other possibilities for the cooling. It is entirely possible that Earth suddenly became significantly cooler before the sunlight was blocked by a large dust cloud. It also might be the case that the darkening of the sun did not happen in other areas except Asia and Europe. For that matter, the dimming of the sun only in some parts of Earth was probably not capable of lowering global temperatures. Without taking into account such possibilities, the author cannot arrive at the conclusion based on this assumption that global temperatures declining significantly were attributed to the dimming of the sun mentioned in the documentation.

Even if one accepts this assumption, the argument is also weakened by the fact that it does not consider the possibility that a large meteorite collision may happen at that point. There are no records mentioning the bright flash of light caused by a large meteorite collision but it does not necessarily follow that the collision did not come to pass. Perhaps it occurred in a desolate place and no individual [can] could possibly know and hence recorded this event. Or perhaps the recordings concerned were lost due to some natural disasters. Thus, the mere fact that “no extant historical records of the time mention such a flash” lends scant support to the author’s conclusion.

Furthermore, there is no evidence provided that the loud boom mentioned in some Asian records at that time was just due to a volcanic eruption. The author overlooks the likelihood that the loud boom was resulted from a thunder in a storm rather than the eruption of a volcano. The recorder [is] was likely to record the loud boom taking place in a thunderstorm and [fails] failed to write down the flash of light coming about at the same time. In short, since the author has not ruled out all other possible [scenarios] 这个词建议换成phenomena that might serve to bring about a loud [storm] boom, I simply cannot take the conclusion seriously.

Finally, the author’s conclusion rests on the postulation that the dimming of the sun has only two alternatives. In all likelihood 十有八九，你真的有这么大的把握吗？, Earth was screened from direct sunlight by some gigantic planet that passed between Earth and Sun. Thus, the author’s claim may mask other causes of the dimming, which may render the conclusion unwarranted.

In conclusion, the argument could be improved by providing evidence that it is a large dust cloud throughout Earth’s atmosphere which blocked sufficient sunlight that lowered global temperatures considerably. It could be further improved by ruling out other possibilities and alternative explanations for dimming the sunlight.
不得不佩服，stoic的文章写的越来越好了，语言很流畅。有一点点问题似乎开头长了点，还有第一点错误找得有点牵强，主要问题应该在没有充分资料证明全球的降温，而不是全球降温了，降温原因却不明。