Which two countries are both likely to have prevailing winds blowing from west to east?

Question

A.  United States and Argentina
B.  United States and Panama
C.  Canada and Brazil
D.  Panama and Brazil

Clarify Question
· What is the key concept addressed by the question?
· What type of thinking is required?

Gather Content
· What do you already know about the Coriolis effect and winds?

Choose Answer
· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?

Reflect on Process
· Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?

Answer 1

A.  United States and Argentina

Clarify Question
· What is the key concept addressed by the question?
        o This question addresses the Coriolis effect and winds.
· What type of thinking is required?
        o This question is asking you to analyze the information given, using logic, to dissect the problem and determine the answer.
 
Gather Content
· What do you already know about the Coriolis effect and winds?
        o If Earth did not rotate on its axis, global air movements would follow simple patterns. But the Earth rotates under the winds, so the winds move in curved paths across the surface, rather than straight paths. The curvature of the paths of the winds due to Earth’s rotation is termed the Coriolis effect.
        o If you were standing on the North Pole, the Earth would appear to be rotating counterclockwise on its axis, but if you were at the South Pole, the Earth would appear to be rotating clockwise. This is why the direction of the Coriolis effect is opposite in the two hemispheres. In the northern hemisphere, winds always curve to the right of their direction of motion; in the southern hemisphere, they always curve to the left.
        o The reason for these wind patterns is that the circumference of the Earth changes with latitude. It is zero at the poles and 38,000 km at the equator. Thus, land surface speed changes from about 0 to 1500 km per hour going from the poles to the equator. Air descending at 30° north latitude may be going roughly the same speed as the land surface below it. As it moves toward the equator, however, it is moving more slowly than the surface below it, so it is deflected to its right in the northern hemisphere and to its left in the southern hemisphere. In other words, in both the northern and southern hemispheres, the winds blow westward as well as toward the equator. The result is that winds on both sides of the equator—called the Trade Winds—blow out of the east and toward the west.
        o Conversely, air masses moving north from 30° are moving more rapidly than underlying land surfaces and thus are deflected again to their right, which in this case is eastward. Similarly, in the southern hemisphere, air masses between 30° and 60° are deflected eastward, to the left. In both hemispheres, therefore, winds between 30° and 60° blow out of the west and toward the east; these winds are called Westerlies.
  Choose Answer
· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
        o In North America, the Westerly winds blow from west to east. On both sides of the equator, the Trade Winds blow from east to west. Further south in the southern hemisphere, though, countries like Argentina have winds from west to east. So the pair of countries with west-to-east winds is the United States and Argentina.
 
Reflect on Process
· Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
        o The question required you to analyze the information given, using logic, to dissect the problem and determine the answer.
        o Did you recognize that in the United States, the prevailing winds are the Westerlies, that blow from west to east?