Argument47 欢迎拍~~汗~40min~8月1日考

carrot_jiayouUID: 2252594

TOPIC: ARGUMENT47 - 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.

This seemingly plausible argument draws a conclusion that the cooling was most probably caused by a volcanic eruption by the support of analysis of some extant historical records of that time. The conclusion suffers a series of fallacies, which renders it unpersuasive as it stands.

At first, these records that author relied on are unconvincing for their limited quantity and unknown origin as the author didn't mention. As it goes that few historical records survive from that time for the limited civilization level at the time, the smaller the quantity of the records is, the less reliable the evidence is, and the less convincing the conclusion is. The author mentioned that no extant historical of the time mention a sudden bright flash of light, which a large meteorite collision would create. Nevertheless, such records are very likely to be destroyed during the long period of time till now. Or maybe people saw such flash of light had no ability to record and express the phenomenon. Without sufficient evidence of a more significant amount and a more clearly idea who and how made that record, I cannot see the records are persuasive.

When it is reliable that the records author mentioned, as Asian and European civilization are relatively advanced at that time, the author's analysis is still doubtful to me. The author makes assumption that the earth's extreme cooling is caused by either a huge volcanic eruption or a large meteorite colliding with earth. A lot of causes should be take into account, such as lower overall universal temperatures at that time, earth went a little bit away from its origin orbit that receive less sunshine as a result, or a temporary thicker of atmosphere that blocks more sunlight to lower global temperatures. A more comprehensive consideration might make the conclusion more reliable.

Last but not the least, a sudden bright flash of light is just a probable expression of a large meteorite collision. Perhaps the collision that time cause no flash, or maybe the collision happened in daytime that flash of light cannot be seen, let alone to be recorded. In the other place, the record that mentioned a loud boom is only proved to be consistent with a volcanic eruption, which not means that is resulted by the eruption. A enormous meteorite colliding with Earth also can make such a great loud boom.

Without more clear evidence and a more reasonable analysis, I cannot believe in the conclusion.

自己修改了一遍文字错误~

[ 本帖最后由 carrot_jiayou 于 2007-7-24 22:23 编辑 ]

最後の使徒UID: 2257608

实在没精力了, 明天再看