欢迎拍作文 argument 50 [传说中的彗星题。。求指教！]

crazyjooUID: 2805124

TOPIC: ARGUMENT50 - From a draft textbook manuscript submitted to a publisher.
"As Earth was being formed out of the collision of space rocks, the heat from those collisions and from the increasing gravitational energy of the planet made the entire planet molten, even the surface. Any water present would have evaporated and gone off into space. As the planet approached its current size, however, its gravitation became strong enough to hold gases and water vapor around it as an atmosphere. Because comets are largely ice made up of frozen water and gases, a comet striking Earth then would have vaporized. The resulting water vapor would have been retained in the atmosphere, eventually falling as rain on the cooled and solidified surface of Earth. Therefore, the water in Earth's oceans must have originated from comets."
WORDS: 454          TIME: 00:50:22         DATE: 2000-7-23 21:15:48

The argument is well present, but not thoroughly reasoned. By citing the feature of the forming process of Earth and the nature of comets, the arguer's claim that the water in Earth's oceans must have derived from comets seems logical.

In the first place, there is no evidence indicate that Earth had been stroked by comets after it approached its current size. Otherwise, all the comets striking Earth will  evaporated and finally disappear in outer space. Even we accept this assumption that Earth had been stroked by comets after it approached its current size, in the absence of the concrete difference in the earth surface between the forming Earth and the Earth which had already approached its current size, it is impossible to conclude that the comets will leave any water on Earth. Understandably, if the characteristic of the surface of Earth had changed over the forming process, that is to say, any water present would still evaporate and go off into space, comets were no expected to be the origin of the water in Earth's oceans.

In the second place, as a threshold problem, the arguer fails to inform us whether or not the surface of Earth became cooled and solidified as soon as the earth approached its current size. Even earth had been stroked by comets after it approached its current size as the arguer assumes, however,  if the comets hit the earth before the surface of Earth became cooled, it is tempting to think that the water and gases of the comets would retain in the atmosphere and then fall as rain on the heat molten surface. As soon as the water arrived on the heat surface, or more probably, when it was approaching to the land, the water present evaporated again. If this repeated process was long enough, it is very likely that the water from the comets would finally turn into other material by chemical reaction or merely go off into space.

In the third place, the arguer presumptuously assumes that the water from the comets is the only origin of the water in Earth's oceans. A myriad of other factors may also form the water in oceans. Perhaps it's the chemical reaction between various elements that produce the water. Or perhaps underground water can break the surface of Earth because there is not more heat which prevent the underground water from approaching
to the surface to some extend.

To sum up, the argument is not as persuasive as it stands. To make it more logically acceptable, the arguer should make a comprehensive analysis about the relevant scientific records. In addition, the argument may be more convincing if the arguer rules out other possibilities that might contribute to the forming of water in Earth and tells us when the surface of Earth became cooled and solidified.

starfirezhuUID: 2842465

TOPIC: ARGUMENT50 - From a draft textbook manuscript submitted to a publisher.
"As Earth was being formed out of the collision of space rocks, the heat from those collisions and from the increasing gravitational energy of the planet made the entire planet molten, even the surface. Any water present would have evaporated and gone off into space. As the planet approached its current size, however, its gravitation became strong enough to hold gases and water vapor around it as an atmosphere. Because comets are largely ice made up of frozen water and gases, a comet striking Earth then would have vaporized. The resulting water vapor would have been retained in the atmosphere, eventually falling as rain on the cooled and solidified surface of Earth. Therefore, the water in Earth's oceans must have originated from comets."
WORDS: 454          TIME: 00:50:22         DATE: 2000-7-23 21:15:48

[Introduction]...
The argument is well presented, but not thoroughly reasoned. By citing the feature of the forming process of Earth and the nature of comets, the arguer's boldly (claims) declares that the water in Earth's oceans must have derived from comets seems logical. {用declare，加上boldly修饰，更能表现出对于辩论者武断言论的评判立场。}

[No evidence shows that comets have collided the earth after it has got enough gravitation]...
In the first place, there is no evidence indicateing that Earth had been stroked by comets after it approached its current size. Otherwise, all the comets striking Earth will  evaporated and finally disappear in outer space. Even we accept this assumption that Earth had been stroked by comets after it approached its current size, in the absence of the concrete difference in the earth's surfaces between the forming early Earth and the Earth which had already approached its current size, it is impossible to conclude that the comets will leave any water on Earth {Why? After the earth had got this current size, the gravitation on its surface could grasped anything collided into it, including water from comets.}. Understandably, if the characteristics of the surface of Earth had changed over the forming process, that is to say, any water present would still evaporate and go off into space, comets were not expected definitely supposed to be the origin of the water in Earth's oceans.

[If the surface of Earth remains hot enough, no water can retain and no oceans can be formed...] XXXX
In the second place, as a threshold problem, the arguer fails to inform us whether or not the surface of Earth became cooled and solidified as soon as the earth approached its current size. Even earth had been stroked by comets after it approached its current size as the arguer assumes, however,  if the comets hit the earth before the surface of Earth became cooled, it is tempting to think that the water and gases of the comets would retain in the atmosphere and then fall as rain on the heat molten surface. As soon as the water arrived on the heat hot surface, or more probably, when it was approaching to the land, the water present evaporated again. If this repeated process was long enough, it is very likely that the water from the comets would finally turn into other material by chemical reaction or merely go off into space. {What you are opposing against is not the point the arguer intends to express!}
Perhaps, you can use this argument instead: [No evidence shows that there are great number of comets colliding the earth and bringing about huge amount of water that necessary to form the oceans on Earth...]


[At least the comets are not the only origin of water...]
In the third place, the arguer presumptuously assumes that the water from the comets is the only origin of the water in Earth's oceans. A myriad of other factors may also form the water in oceans. Perhaps it's the chemical reaction between various elements that produce the water. Or perhaps underground water can break the surface of Earth because there is not more heat which prevent the underground water from approaching
to the surface to some extendt. {You should put more stuff here...}

[Need more study... consider other possibilities... What remedies should be made to defend this argument...]
To sum up, the argument is not as persuasive as it stands. To make it more logically acceptable, the arguer should make a comprehensive analysis study about the relevant scientific records. In addition, the argument may be more convincing if the arguer rules out other possibilities that might contribute to the forming of water in Earth and tells us when the surface of Earth became cooled and solidified.