首页
登录
职称英语
The molecules of carbon dioxide in the Earth’s atmosphere affect the heat bal
The molecules of carbon dioxide in the Earth’s atmosphere affect the heat bal
游客
2025-04-26
38
管理
问题
The molecules of carbon dioxide in the Earth’s atmosphere affect the heat balance of the Earth by acting as a one-way screen. Although these molecules allow radiation at visible wavelengths, where most of the energy of sunlight is concentrated, to pass through, they absorb some longer wave- length, infrared emissions radiated from the Earth’s surface, radiation that would otherwise be transmitted back into space. For the Earth to maintain a constant average temperature, such emissions from the planet must balance incoming solar radiation. If there were no carbon dioxide in the atmosphere, heat would escape from the Earth much more easily. The surface temperature would be so much lower that the oceans might be a solid mass of ice.
Today, however, the potential problem is too much carbon dioxide. The burning of fossil fuels and the clearing of forests have increased atmospheric carbon dioxide by about 15 percent in the last hundred years, and we continue to add carbon dioxide to the atmosphere. Could the increase in car- bon dioxide cause a global rise in average temperature7 Mathematical models that allow us to calculate the rise in temperature as a function of the increase indicate that the answer is probably yes.
Under present conditions a temperature of - 18℃ can be observed at an altitude of 5 to 6 kilo-meters above the Earth. Below this altitude (called the radiating level), the temperature increases by about 6℃ per kilometer approaching the Earth’s surface, where the average temperature is about 15℃. An increase in the amount of carbon dioxide means that there are more molecules of carbon dioxide to absorb infrared radiation. As the capacity of the atmosphere to absorb infrared radiation increases, the radiating level and temperature of the surface must rise.
One mathematical model predicts that doubling the atmospheric carbon dioxide would raise the global mean surface temperature by 2.5℃. This model assumes that the atmosphere’s relative humidity remains constant and the temperature decreases with altitude at a rate of 6.5℃ per kilometer. The assumption of constant relative humidity is important, because water vapor in the atmosphere is another efficient absorber of radiation at infrared wavelengths. Because warm air can hold more moisture than cool air, the relative humidity will be constant only if the amount of water vapor in the atmosphere increases as the temperature rises. Therefore, more infrared radiation would be absorbed and reradiated back to the Earth’s surface. The resultant warming at the surface could be expected to melt snow and ice, reducing the Earth’s reflectivity. More solar radiation would then be absorbed leading to further increase in temperature. [br] According to the passage, the greatest part of the solar energy that reaches the Earth is ______.
选项
A、reflected back to space by snow and ice
B、concentrated at visible wavelengths
C、absorbed by carbon dioxide molecules
D、absorbed by atmospheric water vapor
答案
B
解析
从文中第一段allow radiation at visible wavelengths,where most oft he energy of sunlight is concentrated,to pass through)可以判断大部分太阳能量集中在visible wavelengths。
转载请注明原文地址:https://tihaiku.com/zcyy/4054469.html
相关试题推荐
Duringthenormaldevelopmentofself,achildisaffectedbycertaininflue
Duringthenormaldevelopmentofself,achildisaffectedbycertaininflue
Duringthenormaldevelopmentofself,achildisaffectedbycertaininflue
Duringthenormaldevelopmentofself,achildisaffectedbycertaininflue
Duringthenormaldevelopmentofself,achildisaffectedbycertaininflue
Duringthenormaldevelopmentofself,achildisaffectedbycertaininflue
Duringthenormaldevelopmentofself,achildisaffectedbycertaininflue
ThespectacularaurorallightdisplaysthatappearinEarth’satmospherearou
ThespectacularaurorallightdisplaysthatappearinEarth’satmospherearou
ThespectacularaurorallightdisplaysthatappearinEarth’satmospherearou
随机试题
[originaltext]M:I’mAviArditti,andthisweekonWordmaster.wehaveaspecia
【S1】[br]【S10】E根据前面的所属格推测这里需要名词,而根据pyramid可以推测应该是construction。
Whatisthepurposeofissuingthenewlaw?[originaltext]LawmakersinNebra
Today,houseworkhasbeenmademucheasierbyelectrical______.A、appliancesB、f
女性,40岁,因患甲亢曾接受”131I治疗,近2年来自觉乏力、畏寒,眼睑及下肢
患儿,10岁。课间活动时,突然两眼凝视,呆立不动,呼之不应,持续约10秒后恢复正
2009年3月1日,王某入职某公司,劳动合同约定每月10日为工资发放日。入职后的
属于大环内酯类抗生素的是A.克拉维酸 B.罗红霉素 C.阿米卡星 D.头孢
下列关于纳税信用管理的表述中,符合规定的是( )。A.非独立核算分支机构可自愿
下列有关财务管理目标的观点中,考虑了所获利润和投入资本数额的关系的有()。A.
最新回复
(
0
)