D
The recent, apparently successful, prediction by mathematical models of an appearance of El Nino—the warm ocean How that periodically develops along the Pacific coast of South America has excited researchers．Jacob Bjerknes pointed out years ago how winds might create either abnormally warm or abnormally cold water in the eastern equatorial （赤道附近的） Pacific．Nevertheless, before the creation of the models, no one could explain why conditions should regularly change between appearances of the warm El Nino and the so-called anti-El Nino．The answer, at least if the current model that links the behavior of the ocean to that of the atmosphere is correct, is to be found in the ocean．
It has long been known that during an El Nino, two conditions exist: unusually warm water extends along the eastern Pacific and winds blow from the west into the warmer air rising over the warm water in the east．The contribution of the model is to show that the winds of an El Nino, which raise sea level in the east, send a signal to the west lowering sea level at the same time．According to the model, that signal is created as a negative （负的） Rossby wave, a wave of lower sea level, that moves westward parallel to the equator at 25 to 85 kilometers per day．Taking months to move across the Pacific, Rossby waves march to the western boundary of the Pacific basin, which is modeled as a smootli wall but in reality consists of quite irregular island chains．
When the waves meet the western boundary, they are reflected, and the model predicts that Rossby waves will be broken into many coastal Kelvin waves carrying the same negative sea-level signal．These eventually shoot toward the equator, and then head eastward along the equator drove by the earth at a．speed of about．250 kilometers per day．When enough Kelvin waves of adequate amplitude （振幅） arrive from the western Pacific, their negative sea-level signal overcomes the feedback mechanism, raising the sea level, and they begin to drive the system into the opposite cold mode．This produces a gradual change in winds, one that will eventually send positive sea-level Rossby waves westward, waves that will eventually return as cold cycle—ending positive Kelvin waves beginning another warming cycle．
67．What is the passage mainly about?
A．How Rossby waves are found．
B．Where El Nino is formed．
C．What the models predict．
D．How the models work．
68．Where does El Nino often appear?
A．Along the western coast of the USA .
B．In the Pacific in the south, of the equator．
C．In the Pacific in the north of the equator．
D．Along the southern coast of South America．
69．What is right according to the passage?
A．Rossby waves and Kelvin waves move in opposite directions along the equator．
B．People could explain El Nino before the creation of the mathematical models．
C．Adequate sea-level waves can produce westward positive cold cycle．
D．The speed of Rossby waves is faster than that of Kelvin waves．
70．What does the underlined word "waves" in Paragraph 3 refer to?
A．Kelvin waves．       B．Sea-level signals．   C．Coastal waves．   D．Rossby waves．

A woman wears a face mask to protect her from polluted air in Lanzhou, China, in December．
A new study showed air pollution might put people more at risk for heart disease than scientists had thought．Kristin Miller, a doctoral student at the University of Washington, said chances of getting the disease were related to not only which city a woman lived in, but also where in the city．The study found that the effects of air pollution were often larger within cities than between cities．
The new findings make experts suspect that current pollution limits may be inadequate．Scientists examined rates of heart attack, stroke （中风） and other cardiovascular （心脏血管的） events in women with long-term exposure to air pollution．
The study involved women over the age of fifty who had no sign of cardiovascular disease at the start of the research．The study followed the women for as long as nine years to see how they would develop cardiovascular problems．
The researchers also examined levels of fine particles （粒子，微粒） in the air in 36 areas across the country．That information came from the Environmental Protection Agency．The extremely small particles came from industrial smoke and traffic, along with things like wood-burning fireplaces in houses．
In the study, every ten-microgram increase in pollution was linked to a twenty-four percent increase in the risk of a cardiovascular event．But it was related to a seventy-six percent increase in the risk of death from cardiovascular disease．
But just how do particles in the air damage the cardiovascular system? The particles may cause the lungs to swell and release chemicals from the pollutants into the blood．The chemicals then could damage the heart．
1．The passage mainly talks about______．
A．the effects of pollution on women
B．how to protect women from air pollution
C．how air pollution damages a person’s heart
D．the relationship between air pollution and heart diseases
2．The case of the woman wearing a face mask shows ______．
A．people are paying more and more attention to their health
B．the woman is afraid of getting heart disease
C．Lanzhou city is more heavily polluted than other cities
D．air pollution is becoming more and more serious
3．We can learn from the passage that _______．
A．air pollution is more serious than scientists thought
B．the control of air pollution is effective in some cities
C．people throughout a city have the same risk of getting heart diseases
D．air pollution affects women more than men
4．The study implies that ______．
A．air pollution has a bigger effect on older women than younger women
B．small particles in the air mainly come from industrial smoke
C．the rise in air pollution may lead to a higher death rate from cardiovascular disease
D．air pollution has been affecting people for as long as nine years in the city of Lanzhou

         A woman wears a face mask to protect her from polluted air in Lanzhou, China, in December．

         A new study showed air pollution might put people more at risk for heart disease than scientists had thought．Kristin Miller, a doctoral student at the University of Washington, said chances of getting the disease were related to not only which city a woman lived in, but also where in the city．The study found that the effects of air pollution were often larger within cities than between cities．

         The new findings make experts suspect that current pollution limits may be inadequate．Scientists examined rates of heart attack, stroke （中风） and other cardiovascular （心脏血管的） events in women with long-term exposure to air pollution．

         The study involved women over the age of fifty who had no sign of cardiovascular disease at the start of the research．The study followed the women for as long as nine years to see how they would develop cardiovascular problems．

         The researchers also examined levels of fine particles （粒子，微粒） in the air in 36 areas across the country．That information came from the Environmental Protection Agency．The extremely small particles came from industrial smoke and traffic, along with things like wood-burning fireplaces in houses．

         In the study, every ten-microgram increase in pollution was linked to a twenty-four percent increase in the risk of a cardiovascular event．But it was related to a seventy-six percent increase in the risk of death from cardiovascular disease．

         But just how do particles in the air damage the cardiovascular system? The particles may cause the lungs to swell and release chemicals from the pollutants into the blood．The chemicals then could damage the heart．

1．The passage mainly talks about______．

         A．the effects of pollution on women

         B．how to protect women from air pollution

         C．how air pollution damages a person’s heart

         D．the relationship between air pollution and heart diseases

2．The case of the woman wearing a face mask shows ______．

         A．people are paying more and more attention to their health

         B．the woman is afraid of getting heart disease

         C．Lanzhou city is more heavily polluted than other cities

         D．air pollution is becoming more and more serious

3．We can learn from the passage that _______．

         A．air pollution is more serious than scientists thought

         B．the control of air pollution is effective in some cities

         C．people throughout a city have the same risk of getting heart diseases

         D．air pollution affects women more than men

4．The study implies that ______．

         A．air pollution has a bigger effect on older women than younger women

         B．small particles in the air mainly come from industrial smoke

         C．the rise in air pollution may lead to a higher death rate from cardiovascular disease

         D．air pollution has been affecting people for as long as nine years in the city of Lanzhou

       A woman wears a face mask to protect her from polluted air in Lanzhou, China, in December．

       A new study showed air pollution might put people more at risk for heart disease than scientists had thought．Kristin Miller, a doctoral student at the University of Washington, said chances of getting the disease were related to not only which city a woman lived in, but also where in the city．The study found that the effects of air pollution were often larger within cities than between cities．

       The new findings make experts suspect that current pollution limits may be inadequate．Scientists examined rates of heart attack, stroke （中风） and other cardiovascular （心脏血管的） events in women with long-term exposure to air pollution．

       The study involved women over the age of fifty who had no sign of cardiovascular disease at the start of the research．The study followed the women for as long as nine years to see how they would develop cardiovascular problems．

       The researchers also examined levels of fine particles （粒子，微粒） in the air in 36 areas across the country．That information came from the Environmental Protection Agency．The extremely small particles came from industrial smoke and traffic, along with things like wood-burning fireplaces in houses．

       In the study, every ten-microgram increase in pollution was linked to a twenty-four percent increase in the risk of a cardiovascular event．But it was related to a seventy-six percent increase in the risk of death from cardiovascular disease．

       But just how do particles in the air damage the cardiovascular system? The particles may cause the lungs to swell and release chemicals from the pollutants into the blood．The chemicals then could damage the heart．

1．The passage mainly talks about______．

       A．the effects of pollution on women

       B．how to protect women from air pollution

       C．how air pollution damages a person’s heart

       D．the relationship between air pollution and heart diseases

2．The case of the woman wearing a face mask shows ______．

       A．people are paying more and more attention to their health

       B．the woman is afraid of getting heart disease

       C．Lanzhou city is more heavily polluted than other cities

       D．air pollution is becoming more and more serious

3．We can learn from the passage that _______．

       A．air pollution is more serious than scientists thought

       B．the control of air pollution is effective in some cities

       C．people throughout a city have the same risk of getting heart diseases

       D．air pollution affects women more than men

4．The study implies that ______．

       A．air pollution has a bigger effect on older women than younger women

       B．small particles in the air mainly come from industrial smoke

       C．the rise in air pollution may lead to a higher death rate from cardiovascular disease

       D．air pollution has been affecting people for as long as nine years in the city of Lanzhou

D

       The recent, apparently successful, prediction by mathematical models of an appearance of El Nino—the warm ocean How that periodically develops along the Pacific coast of South America has excited researchers．Jacob Bjerknes pointed out years ago how winds might create either abnormally warm or abnormally cold water in the eastern equatorial （赤道附近的） Pacific．Nevertheless, before the creation of the models, no one could explain why conditions should regularly change between appearances of the warm El Nino and the so-called anti-El Nino．The answer, at least if the current model that links the behavior of the ocean to that of the atmosphere is correct, is to be found in the ocean．

       It has long been known that during an El Nino, two conditions exist: unusually warm water extends along the eastern Pacific and winds blow from the west into the warmer air rising over the warm water in the east．The contribution of the model is to show that the winds of an El Nino, which raise sea level in the east, send a signal to the west lowering sea level at the same time．According to the model, that signal is created as a negative （负的） Rossby wave, a wave of lower sea level, that moves westward parallel to the equator at 25 to 85 kilometers per day．Taking months to move across the Pacific, Rossby waves march to the western boundary of the Pacific basin, which is modeled as a smootli wall but in reality consists of quite irregular island chains．

       When the waves meet the western boundary, they are reflected, and the model predicts that Rossby waves will be broken into many coastal Kelvin waves carrying the same negative sea-level signal．These eventually shoot toward the equator, and then head eastward along the equator drove by the earth at a．speed of about．250 kilometers per day．When enough Kelvin waves of adequate amplitude （振幅） arrive from the western Pacific, their negative sea-level signal overcomes the feedback mechanism, raising the sea level, and they begin to drive the system into the opposite cold mode．This produces a gradual change in winds, one that will eventually send positive sea-level Rossby waves westward, waves that will eventually return as cold cycle—ending positive Kelvin waves beginning another warming cycle．

67．What is the passage mainly about?

       A．How Rossby waves are found．

       B．Where El Nino is formed．

       C．What the models predict．

       D．How the models work．

68．Where does El Nino often appear?

       A．Along the western coast of the USA .

       B．In the Pacific in the south, of the equator．

       C．In the Pacific in the north of the equator．

       D．Along the southern coast of South America．

69．What is right according to the passage?

       A．Rossby waves and Kelvin waves move in opposite directions along the equator．

       B．People could explain El Nino before the creation of the mathematical models．

       C．Adequate sea-level waves can produce westward positive cold cycle．

       D．The speed of Rossby waves is faster than that of Kelvin waves．

70．What does the underlined word "waves" in Paragraph 3 refer to?

       A．Kelvin waves．       B．Sea-level signals．   C．Coastal waves．   D．Rossby waves．