GRE Argument Essay 128
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.
The study of historical weather patterns indicates that in the mid-sixth century earth suddenly became significantly cooler. In accordance with this, few accounts found both in Asia and Europe mention a dimming of sun and extremely cold temperatures. In the argument given above, the author mentions that there could be either a meteorite collision or a large volcanic eruption responsible for this. He further concludes some volcanic eruption to be the cause by giving example of some Asian records that mention a large boom. However, the author has made far too many assumptions
First of all, he has mentioned only two possibilities of the sudden cooling of earth in the mid of sixth century. A little more survey about the scientific developments could have given a wide range of possible reasons for the same. Second, the author’s belief that the sudden cooling of earth was due to a volcanic eruption stands quite weak. He has based his theory on the assumption that the loud boom mentioned in the few Asian records was due to the volcanic eruption although no proof for the same has been established. Further, the dimming of sun is associated with the possible dust clouds formed due to volcanic eruption.
Third, a loud boom may be suggestive of a meteorite collision as well. As far as the dimming of sun is concerned, it could be due to dust clouds in the atmosphere, which is equally possible due to collision with a meteorite.
Fourth, the argument simply rejects the possibility of a meteorite collision responsible for the dimming of sun since no accounts of a bright flash of light are available. Keeping in view the scarcity of accounts available for the cooling of earth itself, one cannot simply reject the possibility of a meteorite collision due to lack of records in its favor, as it is clear that there is a huge shortage of historical accounts of the mid-sixth century.
In addition to this, the loud boom seems more likely due to a meteorite collision rather than a volcanic eruption. As there are higher chances of a volcanic eruption, its sound and effect being more limited to certain regions, in comparison to the effect and sound of a meteorite collision.
Another point of contradiction to the given argument is the cooling of earth due to volcanic eruption. Though, the dust and gases could have blocked the sun and hence the heat, there is no mention of the heat generated by the lava of the volcano. Furthermore, there would have been more evidence available in the form of the mineral rich lava which erupted from the volcano. Neither the scientists, nor the above argument draws support from such possible evidence. This in turn, weakens the given argument as it is based more on assumptions.
Although, it may be established that the dimming of sun and sudden cooling of earth could be either due to some meteorite collision or due to some volcanic eruption, there seems to be no substantial reason for the author to arrive at any conclusion at this point of time .