首页
登录
职称英语
One of the most difficult aspects of deciding whether current climatic event
One of the most difficult aspects of deciding whether current climatic event
游客
2025-04-03
11
管理
问题
One of the most difficult aspects of deciding whether current climatic events reveal evidence of the impact of human activities is that it is hard to get a measure of what constitutes the natural variability of the climate. We know that over the past millennia the climate has undergone major changes without any significant human intervention. We also know that the global climate system is immensely complicated and that everything is in some way connected, and so the system is capable of fluctuating in unexpected ways. We need therefore to know how much the climate can vary of its own accord in order to interpret with confidence the extent to which recent changes are natural as opposed to being the result of human a activities.
Instrumental records do not go back far enough to provide us with reliable measurements of global climatic variability on timescales longer than a century. What we do know is that as we include longer time intervals, the record shows increasing evidence of slow swings in climate between different regimes. To build up a better picture of fluctuations appreciably further back in time requires us to use proxy records.
Over long periods of time, substances whose physical and chemical properties change with the ambient climate at the time can be deposited in a systematic way to provide a continuous record of changes in those properties overtime, sometimes for hundreds or thousands of years. Generally, the layering occurs on an annual basis, hence the observed changes in the records can be dated. Information on temperature, rainfall, and other aspects of the climate that can be inferred from the systematic changes in properties is usually referred to as proxy data. Proxy temperature records have been reconstructed from ice core drilled out of the central Greenland ice cap, calcite shells embedded in layered lake sediments in Western Europe, ocean floor sediment cores from the tropical Atlantic Ocean, ice cores from Peruvian glaciers, and ice cores from eastern Antarctica. While these records provide broadly consistent indications that temperature variations can occur on a global scale, there are nonetheless some intriguing differences, which suggest that the pattern of temperature variations in regional climates can also differ significantly from each other. [br] Which of the following must we find out in order to determine the impact of human activities upon climate?
选项
A、The major changes in climate over the past millennia.
B、The best method for measuring climatic change.
C、The degree to which the climate varies naturally.
D、The millennium when humans began to interfere with the climate.
答案
C
解析
细节题。从文章第一段最后一句可知,我们需要了解气候在多大程度上自然地发生变化(how much the climate can vary of its own accord),由此才能了解人类活动在多大程度上影响环境的变化。故可知C选项正确。
转载请注明原文地址:https://tihaiku.com/zcyy/4024825.html
相关试题推荐
Hefeltitratherdifficulttotakeastand______theopinionofthemajority.A
Idon’tknowwhetherwhatshesaidistrue,butI’lltryto______it.A、confineB
Canyou______yourexplanationalittle?—It’sdifficulttounderstand.A、magnify
Theexplanationinthefootnote______thedifficultsentence.A、modifiedB、classi
Thepointat______atthemeetingiswhethertheyaretoimporttheassemblylin
Largelyduetotheuniversitytraditionandthecurrentacademicmilieu,everyc
Colour-blindpeopleoftenfinditdifficultto______betweenblueandgreen.(2
Colour-blindpeopleoftenfinditdifficultto______betweenblueandgreen.A、s
Thecurrent______withexamresultsisactuallyharmingchildren’seducation.(
Itisimpossibleto______whethershe’llbewellenoughtocomehomefromtheh
随机试题
Thesegoodsare______forexport,thoughafewofthemmaybesoldonthehomema
HowtoGetaPaperPublishedI.Prerequisite—doing(1
Oneofthequestionsthatiscomingintofocusaswefacegrowingscarcityo
结核分枝杆菌根据其代谢特点分A.4群 B.6群 C.5群 D.2群 E.
患者,男,53岁。前胸区局部红肿热痛感染表现,无波动。体温37.4℃,红肿区中央
我国国有资产管理部门或其授权部门持有(),履行国有资产的保值增值和通过国家控股
医学人道主义的根本思想A.尊重患者的生命 B.尊重患者的人格与尊严 C.
在泥石流勘察中,泥石流流体密度的含义是指下列哪一项? (A)泥石流流体质量和泥
奥运一百多年的历史始终陷入一种,一方面它高扬超越民族的人类精神,另一方面参与竞
某病人,13岁,在生活中养成不良的抽烟习惯,父母非常恼火,心理医师建议其采取的较
最新回复
(
0
)