AT350 EXAM #2 November 18, 2003

Transcription

1 AT350 EXAM #2 November 18, 2003 Name and ID: Enter your name and student ID number on the answer sheet and on this exam. Record your answers to the 50 questions by using a No. 2 pencil to completely fill the appropriate circle on the answer sheet. The exam will be computer graded, so be sure to follow the marking instructions provided on the answer sheet. The exam is closed book, closed notes. No calculators are permitted. When you are finished, turn in both the exam and the answer sheet to the teaching assistants. Good luck! 1) Cold air advection below 500-hPa will lead to than normal geopotential heights and than normal atmospheric pressure above the cooling. a. higher, higher b. higher, lower c. lower, higher d. lower, lower 2) In a thermally indirect circulation, warm air is associated with surface pressure, and cold air associated with surface pressure. a. high, high b. high, low c. low, low d. low, high 3) On surface chart the wind tends to blow: t right angles to the isobars or contour lines b. parallel to the isobars or contours c. at an angle between 10 and 30 to the contours and towards lower pressure d. at constant speed 4) Which of the statements below is not correct concerning the pressure gradient force? a. the PGF points from high to low pressure in the Northern Hemisphere b. it is non-existent at the equator c. it can cause the wind to speed up or slow down d. the PGF points from high to low pressure in the Southern Hemisphere

2 5) The force that would cause a stationary parcel of air to begin to move horizontally is called the: a. Coriolis force b. pressure gradient force entripetal force d. frictional force 6) If the earth stopped rotating which of the following would not be true? a. surface winds would blow from high toward low pressure b. there would still be a Coriolis force c. there would still be a pressure gradient force d. there would still be a gravitational force 7) Suppose that the winds aloft are geostrophic and blowing from the south. If you are in the Northern Hemisphere, low pressure is located to the: a. north b. south c. east d. west 8) Suppose you are in the Southern Hemisphere, and that the winds aloft are geostrophic and blowing from the south. With the same orientation of isobars at the surface, the surface winds would blow from the: a. southwest b. northwest c. northeast d. southeast 9) You are in the center of the surface low as a storm develops in the Southern Hemisphere. The upper level winds above you are likely blowing from the. a. northwest b. southwest c. southeast d. northeast 10) During the summer along the coast, a land breeze (wind from the land to the sea) is usually strongest and best developed: a. in the afternoon b. just after sunrise c. just before sunset d. just before noon e. around midnight

3 11) The world's deserts are found at 30 latitude because: a. the intertropical convergence zone is located there b. the jet stream is overhead c. of the convergence of the prevailing westerlies and the trades d. the sinking air in the subtropics suppresses precipitation 12) As an air parcel moving westerly aloft moves away from the equator in the Southern Hemisphere, the air parcel's motion relative to the earth should: a. remain constant b. slow and eventually reverse direction c. slow but continue in the same direction d. increase in speed Use the following diagram to answer questions c b d a e 13) Imagine the above land mass represents a side view of Antarctica. If a strong katabatic wind has set up, at what point(s) would you expect to find clouds forming (hint: the answer is E)? a. Between c and d. b. At point b only. c. Between b and d. d. Between b and c. e. Probably none of the above, but Dave never talked about this. Bad Dave. 14) Where would you expect the highest pressure above the surface when the katabatic wind starts? a. point a b. point b c. point c d. point d e. point e

4 15) Point c is at 3000m and point e is at sea-level. If the air at point c is 40 degrees Celsius, then what temperature would you expect the air to be at point a (see useful information at the back)? a. -40 C b. -32 C c. -16 C d. -10 C e. 0 C Use the following diagram to answer questions Note that the figure is for the Southern Hemisphere. f g h i j Hadley Cell Ferrell Cell a b c d e Equator 30 South 60 South 16) Where would you expect to find the least precipitation? 17) Where would you expect to find the most precipitation? 18) Where would you expect to find the strongest surface easterly winds? e. g

5 19) Where would you expect to find the strongest surface westerly winds? e. i 20) Where would you find the highest geopotential heights aloft? a. f b. g c. h d. i e. j Use the following diagram of a surface low pressure center in the Northern Hemisphere to answer questions d c e L a g Latitude is 50 North b f 21) Which arrow corresponds to the pressure gradient force? b. g e. f 22) Which arrow corresponds to the Coriolis force? b. g c. b d. e e. f

6 23) Which arrow corresponds to friction? a. f d. g e. d 24) Which arrow corresponds to the direction of the wind? a. d b. f d. b Use the following contour diagram of 500-hPa heights in the tropics to answer questions The solid lines are lines of constant 500-hPa height; the dashed is the Equator. Assume the highest geopotential heights are along the contour line closest to the Equator. c 30 North b a Equator 30 South 25) At point a, the pressure gradient force is directed towards the: a. south b. east c. north d. west e. there is no pressure gradient force at point a 26) At point a, the Coriolis force is directed towards the: a. south b. east c. north d. west e. there is no Coriolis force at point a

7 27) At point c, the wind is likely directed towards the: a. south b. east c. north d. west e. there is no flow at point c 28) At point b, the wind is likely directed towards the: a. south b. east c. north d. west e. there is no flow at point c Consider the following side view of Northern California and the Atlantic Ocean for questions b e d Up a f c California Pacific Ocean 29) If it is 5 am during the summer, at what point would you expect the strongest wind to blow from the land to the ocean? c. e d. f e. c 30) If it is 5 am during the summer, where would you expect to find the heighest 500-mb geopotential heights? a. b b. e c. d d. a e. c

8 31) If it is 5am during the summer, where would you expect to find the lowest surface pressure? b. f d. b e. d 32) If it was an overcast day, how would this change the strength of an afternoon seabreeze (from the sea to the land)? a. no difference b. it would strengthen the sea breeze c. it would weaken the sea breeze d. it would change the flow aloft, but not at the surface e. it would change the flow at the surface, but not aloft. For questions 33-41, refer to the Northern Hemisphere cyclone depicted below. 5 2 Low ) Severe thunderstorms would most likely be occurring at position:

9 34) Upper level divergence is probably occurring above position: 35) Where is the temperature probably coldest? 36) The winds at point 1 would most likely be from the: a. southwest b. northwest c. northeast d. south e. southeast 37) The winds at point 3 would most likely be from the: a. southwest b. north c. northeast d. east 38) Which position is most likely experiencing overcast conditions with increasing cloudiness? 39) Which position is experiencing the strongest cold advection?

10 40) Above what location would you expect to find an upper level trough? For questions 41-44, refer to the diagram of 500-mb heights below. e d b a c 41) A developing wave cyclone at the surface would most likely be found below: 42) A person at the earth's surface beneath position a would observe clouds overhead (at the 500 mb level) moving from: a. southwest to northeast b. northwest to southeast c. west to east d. southeast to northwest ast to west

11 43) A surface high pressure area would most likely be found beneath point: 44) The most pronounced warm advection at the surface would most likely be found beneath point: 45) The primary ingredients for the formation of a midlatitude cyclone are: a. convergence aloft; horizontal temperature gradients at the surface b. horizontal temperature gradients at the surface; divergence aloft. c. only horizontal temperature gradients at the surface d. convergence aloft; latent heat release Useful information: Dry adiabatic lapse rate=10 C / 1000meters Moist adiabatic lapse rate=6 C / 1000meters Dew point temperature lapse rate= 2 C / 1000 meters Tilt of the earth = 23.5 degrees from the axis of rotation