Elemental Geosystems, 5E (Christopherson) Chapter 4 Atmospheric and Oceanic Circulation

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Elemental Geosystems, 5E (Christopherson) Chapter 4 Atmospheric and Oceanic Circulation Elemental Geosystems, 5e (Christopherson) Chapter 4 Atmospheric and Oceanic Circulation 1) The eruption of Mount Pinatubo in June 1991 A) lofted several million tons of ash, dust, and SO2 into the atmosphere. B) was tracked by AVHRR instruments aboard Earth-orbiting satellites. C) eventually affected almost half the planet after only a few weeks of circulation. D) produced spectacular sunrises and sunsets for almost two years. E) All of these are correct. Answer: E 2) The sulfate particles produced by the eruption of Mount Pinatubo ________ the albedo of the atmosphere, and this ________ the earth. A) increased; warmed B) increased; cooled C) decreased; warmed D) decreased; cooled Answer: B 3) Which of the following refers to primary circulation? A) migratory high and low pressure systems B) the monsoons C) general circulation of the atmosphere D) land-sea breezes Answer: C 4) Which of the following refers to secondary circulation? A) migratory high and low pressure systems B) weather patterns C) general circulation of the atmosphere D) mountain-valley breezes Answer: A 5) Which of the following refers to tertiary circulation? A) migratory high and low pressure systems B) subtropical high pressure systems C) general circulation of the atmosphere D) land-sea breezes Answer: D 6) Air flow is initiated by the A) Coriolis force. B) pressure gradient force. C) friction force. D) centrifugal force. Answer: B 1 7) The horizontal motion of air relative to Earth's surface is A) barometric pressure. B) wind. C) convection flow. D) a result of equalized pressure across the surface. Answer: B 8) Which of the following is not true of the wind? A) It is initiated by the pressure gradient force. B) It blows from regions of high pressure to regions of low pressure. C) The direction of flow can be affected by the rotation of the earth. D) Air blows from regions of hotter air to regions of colder air. E) Winds are named based on the direction from which they blow. Answer: D 9) Normal sea level pressure has a value of A) 1013.2 millibars or 29.92 inches of mercury in a barometer. B) 28.50 inches of lead. C) 32.01 millibars of mercury. D) 500 mb. Answer: A 10) Which of the following is not a correct expression for standard atmospheric pressure at sea level? A) 1 kg/cm2 B) 30.00 millibars C) 29.92 inches of Hg D) 760 mm of Hg (mercury) E) 1013.2 mb Answer: B 11) The average height of a column of mercury (Hg) in a barometer at sea level is A) 760 mm (76 cm). B) 1013 inches. C) something that can not be determined without knowing air temperature. D) 29.00 millibars. Answer: A 12) An instrument used to measure air pressure is A) a thermometer. B) an aneroid barometer. C) a mercury thermometer. D) a bowl of mercury. E) an anemometer. Answer: B 13) An increase in air pressure will cause the mercury in a barometer to ________. A) rise B) fall C) freeze D) None of the above barometers do not measure air pressure. Answer: A 2 14) ________ is used in a barometer because ________. A) Water; it is liquid at normal air temperature B) Water; it weighs more than mercury C) Mercury; it will rise more than water will under the same air pressure D) Mercury; it weighs more than water Answer: D 15) The normal range for air pressure at sea level is A) 500 to 1000 mb. B) 100 to 650 mb. C) 980 to 1050 mb. D) 1060 to 210 mb. Answer: C 16) The highest surface air pressure ever recorded occurred when the air was A) very cold. B) very warm. C) very wet. D) very high above the surface of the earth. Answer: A 17) As air temperature increases, the speed of the molecules in a mass of air ________ and the air pressure ________. A) increases; increases B) increases; decreases C) decreases; increases D) decreases; decreases Answer: A 18) Which of the following describes the pressure gradient force? A) It drives air from areas of higher to lower barometric pressure. B) It decreases with height above the surface. C) It causes apparent deflection of winds from a straight path. D) It is the only force acting on atmospheric flows in the upper troposphere. Answer: A 19) An isoline of equal pressure plotted on a weather map is known as A) an isotherm. B) an equilibrium line. C) an isobar. D) the thermal equator. Answer: C 20) Air flows ________ a surface high pressure area because the density of the air in the high pressure zone is ________ than that of the surrounding air. A) into; more dense B) into; less dense C) out of; more dense D) out of; less dense Answer: C 3 4 21) If the earth did not rotate, air would flow A) perpendicular to the isobars, i.e., straight across the isobars. B) to the right of its direction of motion in the Northern Hemisphere. C) to the left of its direction of motion in the Northern Hemisphere. D) parallel to the isobars. Answer: A 22) Which of the following is true of high pressure areas? A) Air converges and ascends within high pressure systems. B) Air descends and diverges within high pressure systems. C) They generally involve atmospheric pressures lower than 1000 mb. D) They are characteristic for areas along the equator. Answer: B 23) On a weather map of air pressure, what can you infer from a closer spacing of isobars? A) little without knowing temperature patterns B) a steep pressure gradient creating a slower flow of air C) a steep pressure gradient creating a faster flow of air D) higher pressures E) a weak pressure gradient creating a slower flow of air Answer: C 24) Which of the following describes the Coriolis force? A) It drives air from areas of higher to lower barometric pressure. B) It decreases with height above the surface. C) It causes the apparent deflection of winds from a straight path. D) It is the only force acting on flows of air in the upper troposphere. Answer: C 25) Which of the following is true of objects and wind moving over distance and time on Earth's surface? A) They are always deflected from a straight path to the west in the Southern Hemisphere. B) They are affected only by the pressure gradient and friction force. C) They are always deflected to the right by the friction force. D) They are apparently deflected from a straight path to the right in the Northern Hemisphere. Answer: D 26) The deflection produced by the Coriolis force is caused by A) the fact that Earth's rotation decreases in speed toward the poles. B) differing pressure gradients. C) forces that affect winds but not ocean currents. D) air temperature. E) the fact that the earth revolves. Answer: A 27) Which of the following is true regarding the effects of the Coriolis force? A) The amount of Coriolis deflection is uniform from equator to poles. B) Coriolis deflection occurs only along parallels, not meridians. C) The Coriolis force is zero at the poles, increasing to maximum along the equator. D) The Coriolis force is zero along the equator, increasing to one-half of maximum at 30° latitude and maximum at the poles. Answer: D 5 28) The effect of the Coriolis force is ________ in the upper atmosphere because ________. A) enhanced; the pressure gradient is weaker B) enhanced; there is less friction C) enhanced; there is more friction D) diminished; the pressure gradient is weaker E) diminished; there is less friction Answer: B 29) If the earth's direction of rotation were reversed, the SE trades would become A) SW trades. B) NE trades. C) NW trades. D) easterlies. Answer: A 30) In the absence of friction, the combined effect of the Coriolis force and the pressure gradient force produces A) geostrophic winds at high altitudes above the ground. B) surface winds. C) air flow from low to high pressure centers. D) air flow in a north-south direction. E) air flow perpendicular to the isobars. Answer: A 31) Which of the following matches is incorrect relative to air circulation? A) anticyclone = high pressure center B) cyclone = low pressure center C) anticyclone = clockwise circulation in the Southern Hemisphere D) cyclone = counterclockwise in the Northern Hemisphere Answer: C 32) Which of the following matches is correct relative to air circulation? A) anticyclone = low pressure center B) cyclone = high pressure center C) cyclone = clockwise circulation in the Southern Hemisphere D) anticyclone = counterclockwise circulation in the Northern Hemisphere Answer: C 33) Which of the following primary pressure areas are produced by thermal factors, rather than dynamic factors? A) subtropical high and subpolar low B) equatorial low and polar high C) equatorial low and Bermuda high D) Aleutian low and Icelandic low Answer: B 34) The intertropical convergence zone is characterized by A) convergence and uplift of warm surface air. B) convergence and subsidence of cold surface air. C) divergence and uplift of warm surface air. D) divergence and subsidence of cold surface air. Answer: A 6 35) The wind belts used by mariners to travel from Europe to North America during the days of sailing ships were the A) polar easterlies. B) westerlies. C) SE trades. D) NE trades. Answer: D 36) Between 20° to 35° north latitude and 20° to 35° south latitude are A) the largest zone of water surpluses in the world. B) warm and wet conditions, and the world's great tropical forests.
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