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有益补充1:地球轨道根数变化与第四纪冰期 Changes of the Earth's Orbital Elements and the Quaternary Glacial Epoch
米兰柯维奇(Milankovitch)天文气候学理论和第四纪地质时期以来冰期的研究进展.研究结果表明,地球上的冰体积具有近10万yr的变化周期,并伴有近4万yr和2万yr的变化周期,它们是由于地球的轨道根数变化导致的气候变迁所致;不同的地球物理资料中均存在上述类似的变化周期,表明气候变迁所导致的变化是全球性效应,证实米兰柯维奇天文理论是基本正确的。 这个像不像jj里讲的mm理论?    冰川变化 地球轨道
有益补充2 (补充1的英文):
At the recent American Geophysical Union meeting in San Francisco, the 25th anniversary of one of the great
papers in paleoclimatology was celebrated. The paper, entitled “Variations in the Earth’s orbit: Pacemaker
of the Ice Ages,” presented important new evidence supporting the orbital theory of glaciation. Orbital theory goes back over a century but is most closely associated with Milankovitch, who calculated the effects of gravitational perturbations on the seasonal cycle of Earth’s insolation (the radiation incident at the top of the atmosphere). Insolation varies on several time scales, including ~20,000 years (termed precession), ~40,000.
Milankovitch proposed in the early twentieth
   century that the ice ages were caused by variations
   in the Earth’s orbit around the Sun. For some
   time this theory was considered untestable,
   (5)largely because there was no sufficiently precise
   chronology of the ice ages with which the orbital
   variations could be matched.
   P1:M提出一个理论, 指出其缺陷
   To establish such a chronology it is necessary
   to determine the relative amounts of land ice that
   (10)existed at various times in the Earth’s past. A recent
   discovery makes such a determination possible:
   relative land-ice volume for a given period can be
   deduced from the ratio of two oxygen isotopes,
   16 and 18, found in ocean sediments. Almost
   (15)all the oxygen in water is oxygen 16, but a few
   molecules out of every thousand incorporate the
   heavier isotope 18. When an ice age begins, the
   continental ice sheets grow, steadily reducing the
   amount of water evaporated from the ocean that
   (20)will eventually return to it. Because heavier isotopes
   tend to be left behind when water evaporates
   from the ocean surfaces, the remaining ocean
   water becomes progressively enriched in oxygen
   18. The degree of enrichment can be determined
   (25)by analyzing ocean sediments of the period,
   because these sediments are composed of calcium
   carbonate (calcium carbonate: n.[化]碳酸钙) shells of marine organisms, shells that
   were constructed with oxygen atoms drawn from
   the surrounding ocean. The higher the ratio of
   (30)oxygen 18 to oxygen 16 in a sedimentary specimen,
   the more land ice there was when the sediment
   was laid down.
       P2: 一个新发现可弥补M理论的缺陷
   As an indicator of shifts in the Earth’s climate,
   the isotope record has two advantages. First, it is
   (35)a global record: there is remarkably little variation
   in isotope ratios in sedimentary specimens taken
   from different continental locations. Second, it is
   a more continuous record than that taken from
   rocks on land. Because of these advantages,
   (40)sedimentary evidence can be dated with sufficient
   accuracy by radiometric methods to establish a
   precise chronology of the ice ages. The dated
   isotope record shows that the fluctuations in
   global ice volume over the past several hundred
   (45)thousand years have a pattern: an ice age occurs
   roughly once every 100,000 years. These data have
   established a strong connection between variations
   in the Earth’s orbit and the periodicity of the ice
   ages.
       P3:新发现的优点
   However, it is important to note that other
   (50)factors, such as volcanic particulates or variations
   in the amount of sunlight received by the Earth,
   could potentially have affected the climate. The
   advantage of the Milankovitch theory is that it
   is testable: changes in the Earth’s orbit can be
   (55)calculated and dated by applying Newton’s laws
   of gravity to progressively earlier configurations
   of the bodies in the solar system. Yet the lack of
   information about other possible factors affecting
   global climate does not make them unimportant.
       P4:其他的理论也不容忽视
70. In the passage, the author is primarily interested in
   主题题(D)
suggesting an alternative to an outdated research method
introducing a new research method that calls an accepted theory into question
emphasizing the instability of data gathered from the application of a new scientific method
presenting a theory and describing a new method to test that theory(D)
initiating a debate about a widely accepted theory

71. The author of the passage would be most likely to agree with which of the following statements about the Milankovitch theory?
   应用题(D)
It is the only possible explanation for the ice ages.
It is too limited to provide a plausible explanation for the ice ages, despite recent research findings.
It cannot be tested and confirmed until further research on volcanic activity is done.
It is one plausible explanation, though not the only one, for the ice ages. (D)
It is not a plausible explanation for the ice ages, although it has opened up promising possibilities for future research.

72. It can be inferred from the passage that the isotope record taken from ocean sediments would be less useful to researchers if which of the following were true?
推导题(B)
   the isotope record has two advantages. First, it is
   (35)a global record;Second, it is
   a more continuous record than that taken from
   rocks on land
It indicated that lighter isotopes of oxygen predominated at certain times.
It had far more gaps in its sequence than the record taken from rocks on land.否定了第二点
It indicated that climate shifts did not occur every 100,000 years.削弱M理论,而不是方法
It indicated that the ratios of oxygen 16 and oxygen 18 in ocean water were not consistent with those found in fresh water. (B)
It stretched back for only a million years.

73. According to the passage, which of the following is true of the ratios of oxygen isotopes in ocean sediments?
   观点题(C)
   relative land-ice volume for a given period can be
   deduced from the ratio of two oxygen isotopes,
   16 and 18, found in ocean sediments.
They indicate that sediments found during an ice age contain more calcium carbonate than sediments formed at other times.
They are less reliable than the evidence from rocks on land in determining the volume of land ice.
They can be used to deduce the relative volume of land ice that was present when the sediment was laid down.
They are more unpredictable during an ice age than in other climatic conditions. (C)
They can be used to determine atmospheric conditions at various times in the past.

74. It can be inferred from the passage that precipitation formed from evaporated ocean water has
   推导题(B)
   Because heavier isotopes
   tend to be left behind when water evaporates
   from the ocean surfaces, the remaining ocean
   water becomes progressively enriched in oxygen
   18.
the same isotopic ratio as ocean water
less oxygen 18 than does ocean water
less oxygen 18 than has the ice contained in continental ice sheets
a different isotopic composition than has precipitation formed from water on land(B)
more oxygen 16 than has precipitation formed from fresh water

75. It can be inferred from the passage that calcium carbonate shells
   推导题(E)
   shells that
   were constructed with oxygen atoms drawn from
   the surrounding ocean.
are not as susceptible to deterioration as rocks
are less common in sediments formed during an ice age
are found only in areas that were once covered by land ice
contain radioactive material that can be used to determine a sediment’s isotopic composition
reflect the isotopic composition of the water at the time the shells were formed

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大全上的
Milankovitch proposed in the early twentieth century that the ice ages were caused by variations in the Earth’s orbit around the Sun. For sometime this theory was considered untestable, largely because there was no sufficiently precise chronology of the ice ages with which the orbital variations could be matched.
To establish such a chronology it is necessary to determine the relative amounts of land ice that existed at various times in the Earth’s past. A recent discovery makes such a determination possible: relative land-ice volume for a given period can be deduced from the ratio of two oxygen isotopes, 16 and 18, found in ocean sediments. Almost all the oxygen in water is oxygen 16, but a few molecules out of every thousand incorporate the heavier isotope 18. When an ice age begins, the continental ice sheets grow, steadily reducing the amount of water evaporated from the ocean that will eventually return to it. Because heavier isotopes tend to be left behind when water evaporates from the ocean surfaces, the remaining ocean water becomes progressively enriched in oxygen 18. The degree of enrichment can be determined by analyzing ocean sediments of the period, because these sediments are composed of calcium carbonate shells of marine organisms, shells that were constructed with oxygen atoms drawn from the surrounding ocean. The higher the ratio of oxygen 18 to oxygen 16 in a sedimentary specimen, the more land ice there was when the sediment was laid down.
As an indicator of shifts in the Earth’s climate, the isotope record has two advantages. First, it is a global record: there is remarkably little variation in isotope ratios in sedimentary specimens taken from different continental locations. Second, it is a more continuous record than that taken from rocks on land. Because of these advantages, sedimentary evidence can be dated with sufficient accuracy by radiometric methods to establish a precise chronology of the ice ages. The dated isotope record shows that the fluctuations in global ice volume over the past several hundred thousand years have a pattern: an ice age occurs roughly once every 100,000 years. These data have established a strong connection between variations in the Earth’s orbit and the periodicity of the ice ages.
However, it is important to note that other factors, such as volcanic particulates or variations in the amount of sunlight received by the Earth, could potentially have affected the climate. The advantage of the Milankovitch theory is that it is testable: changes in the Earth’s orbit can be calculated and dated by applying Newton’s laws of gravity to progressively earlier configurations of the bodies in the solar system. Yet the lack of information about other possible factors affecting global climate does not make them unimportant.
In the passage, the author is primarily interested in
(A) suggesting an alternative to an outdated research method
(B) introducing a new research method that calls an accepted theory into question
(C) emphasizing the instability of data gathered from the application of a new scientific method
(D) presenting a theory and describing a new method to test that theory
(E) initiating a debate about a widely accepted theory
2.    The author of the passage would be most likely to agree with which of the following statements about the Milankovitch theory?
(A) It is the only possible explanation for the ice ages.
(B) It is too limited to provide a plausible explanation for the ice ages, despite recent research findings.
(C) It cannot be tested and confirmed until further research on volcanic activity is done.
(D) It is one plausible explanation, though not the only one, for the ice ages.
(E) It is not a plausible explanation for the ice ages, although it has opened up promising possibilities for future research.
3.    It can be inferred from the passage that the isotope record taken from ocean sediments would be less useful to researchers if which of the following were true?
(A) It indicated that lighter isotopes of oxygen predominated at certain times.
(B) It had far more gaps in its sequence than the record taken from rocks on land.
(C) It indicated that climate shifts did not occur every 100,000 years.
(D) It indicated that the ratios of oxygen 16 and oxygen 18 in ocean water were not consistent with those found in fresh water.
(E) It stretched back for only a million years.
4.    According to the passage, which of the following is true of the ratios of oxygen isotopes in ocean sediments?
(A) They indicate that sediments found during an ice age contain more calcium carbonate than sediments formed at other times.
(B) They are less reliable than the evidence from rocks on land in determining the volume of land ice.
(C) They can be used to deduce the relative volume of land ice that was present when the sediment was laid down.
(D) They are more unpredictable during an ice age than in other climatic conditions.
(E) They can be used to determine atmospheric conditions at various times in the past.
5.    It can be inferred from the passage that precipitation formed from evaporated ocean water has
(A) the same isotopic ratio as ocean water
(B) less oxygen 18 than does ocean water
(C) less oxygen 18 than has the ice contained in continental ice sheets
(D) a different isotopic composition than has precipitation formed from water on land
(E) more oxygen 16 than has precipitation formed from fresh water
6.    According to the passage, which of the following is (are) true of the ice ages?
I.    The last ice age occurred about 25,000 years ago.
II.    Ice ages have lasted about 10,000 years for at least the last several hundred thousand years.
III.    Ice ages have occurred about every 100,000 years for at least the last several hundred thousand years.
(A) I only
(B) II only
(C) III only
(D) I and only
(E) I, II and III
7.    It can be inferred from the passage that calcium carbonate shells
(A) are not as susceptible to deterioration as rocks
(B) are less common in sediments formed during an ice age
(C) are found only in areas that were once covered by land ice
(D) contain radioactive material that can be used to determine a sediment’s isotopic composition
(E) reflect the isotopic composition of the water at the time the shells were formed
8.    The purpose of the last paragraph of the passage is to
(A) offer a note of caution
(B) introduce new evidence
(C) present two recent discoveries
(D) summarize material in the preceding paragraphs
(E) offer two explanations for a phenomenon
9.    According to the passage, one advantage of studying the isotope record of ocean sediments is that it
(A) corresponds with the record of ice volume taken from rocks on land
(B) shows little variation in isotope ratios when samples are taken from different continental locations
(C) corresponds with predictions already made by climatologists and experts in other fields
(D) confirms the record of ice volume initially established by analyzing variations in volcanic emissions
(E) provides data that can be used to substantiate records concerning variations in the amount of sunlight received by the Earth

OADBCBCEAB

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2.3.4 风暴眼
另一篇是写风暴眼的,研究比较了风暴眼外围和中心的强度(storm wall& storm eye),有题问到有个房子在16th floor story?处在什么情况下其窗户最容易被风broken。我记得好像选了200mile那个

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2.3.5关于宇宙行星
第三篇 关于宇宙行星
JJ上没有。。说通常碰撞后星系中会有一些小的碎片。。 然后根据什么推断它们很年轻。 后来新发现这种行星也有上10^ 年的( 很老的意思), 而且还没有卫星。 然后就有科学家出来解释原因 说了4 点。结构还蛮清楚的, 就是关于星系的生词多。  
有一屏半

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