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DEPARTMENT OF EARTH & CLIMATE SCIENCES NAME _______________________

SAN FRANCISCO STATE UNIVERSITY

ERTH 360.01

Fall 2016 Test #1

September 29, 2016

200 pts

Part I. Surface Chart Interpretation.

Figure 1. Surface Chart for 1500Z 7 September 2007

1. Pressure System A on the chart is a High Pressure area. This means

(a) dew points are high.

(b) the air there is cold.

(c) the air there is warm

(d) the atmospheric pressure (weight) is greater there than in surrounding areas.

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(e) the atmospheric pressure (weight) is lesser there than in surrounding areas.

2. Pressure System B on the chart is a cyclone. This means

(a) dew points are high.

(b) the air there is cold.

(c) the air there is warm

(d) the atmospheric pressure (weight) is greater there than in surrounding areas.

(e) the atmospheric pressure (weight) is lesser there than in surrounding areas.

3. Station 2 (see above) is reporting

(a) a thunderstorm

(b) heavy continuous rain

(c) moderate fog.

(d) heavy continuous snow.

(e) haze.

4. The station(s) with a relative humidity of 100% is (are)

(a) Station 1

(b) Station 2

(c) Station 3

(d) Station 4

(e) Stations 1, 2 and 3.

5. The station(s) with the highest amount of water vapor is

(a) Station 1

(b) Station 2

(c) Station 3

(d) Station 4

(e) Stations 1, 2 and 3.

6. The pressure at Station 1 is

(a) 147 mb

(b) 1010.8 mb

(c) 910.8 mb

(d) 520 mb

(e) 1014.7 mb

7. The FRONT shown on the weather map is

(a) a stationary front

(b) a cold front

(c) a warm front

(d) an occluded front

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Part II. Satellite and Radar Interpretation. Refer to Figs. 2a, 2b, and 2c, and 3.

Fig. 2a. Visible Satellite Image, 1630 UTC 21 Sept 2016 (1 km)

Fig. 2b. Visible Satellite Image, 1630 UTC 21 Sept 2016 (4 km)

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Fig. 2c. Infrared Satellite Image, 1630 UTC 21 Sept 2016 (4 km)

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Fig. 3. Radar Reflectivity, KMUX 1630 UTC 21 Sept 2016

Figures 2a and 2b are the visible satellite image for 1630 UTC 21 September 2016. Fig 2a is zoomed to show

a closeup of our area of California. Fig. 2b is the infrared satellite image at the same time, and Fig. 3 is the

Radar Image (Radar Reflectivity) for our portion of California.

8. With respect to the visible satellite image, Fig. 2a and 2b, the texture in the cloud band located over the

region from the Bay Area to the Sierra Nevada (roughly defined by the letter A) is due to

(a) different cloud colors.

(b) shadows cast by towering cloud forms such as cumulonimbus on the lower overcast.

(c) cold temperatures at 500 mb.

(d) unusually warm sea surface temperatures.

(e) industrial activity in the Sacramento Valley.

9. Fig. 2b and c and Fig. 3 in combination would suggest to meteorologists that

(a) fog is present in the Central Valley.

(b) a hurricane is present near the tip of Baja California.

(c) warm temperatures are occurring in the Central Valley.

(d) dew points are very high over California.

(e) a band of moderate to heavy precipitation is moving through northern California.

10. The information in Fig. 3 suggests that some of the echoes in the area around Modesto maybe associated

with

(a) stratus.

(b) fog.

(c) cumulonimbus.

(d) cirrus spissatus.

(e) nimbostratus.

11. Figures 2a, b, c and 3 together suggest that the main immediate forecast issue over the part of California

shown would be

(a) fog.

(b) frost.

(c) warm temperatures.

(d) low dew points.

(e) thunderstorms in the Central Valley and foothills of the Sierra Nevada.

12. The colors on the radar plot, Fig. 3 indicate

(a) cloud top temperatures.

(b) size of cloud droplets.

(c) visibility.

(d) precipitation intensity.

(e) frequent cloud to ground lightning.

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Part III. Visible Satellite. Refer to Fig. 4.

Fig. 4. Visible Satellite Image, 1845 UTC, 12 August 1997

13. Examination of the satellite image suggests that fog is the dominant cloud form appearing along the

coast (rather than, say, cumulonimbus)

(a) because cumulonimbus does not often occur along the coast.

(b) because the cloudiness appears to outlining the coastline, indicating that it is a low cloud form

restricted to the coastal sections by the topography.

(c) because stratus is the most observed cloud type in California.

(d) because the dewpoint temperatures are high.

(e) because there are few radar sites in California.

14. On Fig. 4, fog is extending inland over the central section of the Bay Area

(a) because upwelling is occurring there.

(b) because Mt Diablo is drawing the fog inland there.

(c) because San Francisco is heating up and drawing the fog inland.

(d) because that is in the region of the Coast Range broken by the Golden Gate.

(e) because the dewpoint temperatures are the highest there.

15. The Santa Cruz Mountains are located roughly at

(a) A

(b) B

(c) C

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(d) D.

(e) E

16. Mt. Tamalpais is located roughly at

(a) A

(b) B

(c) C

(d) D.

(e) E

17. Mt. Diablo is located roughly at

(a) A

(b) B

(c) C

(d) D.

(e) E

Part IV. Advection Fog. Questions 18 to 23 refer to Fig. 5.

Fig. 5. Schematic Section Across Coastline During Typical Summer Afternoon. Sea surface

temperatures are shown. The letters refer to the EXACT location. (D is in the surface of the

ocean, not the atmosphere).

18. An animated visible satellite image would show clouds beginning to form at

(a) A

(b) B

(c) C

(d) D.

(e) None of the locations.

19. A surface high pressure area is located at

(a) A

(b) B

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(c) C

(d) D

(e) None of the locations.

20. Assume that at C the temperature of the air is 70F and the dew point is 63. As the air moves from

C to the Central Valley of California, at which location (roughly) would the relative humidity at the

surface be 100 %.

(a) A

(b) B

(c) C

(d) D

(e) None of the locations.

21. The cloud form developing at A is known as

(a) cumulus

(b) stratus

(c) cumulonimbus

(d) altostratus

(e) cirrocumulus

22. As air moves from C to the Central Valley, which of the following meteorological characteristics of

the air parcel will NOT change markedly?

(a) its temperature

(b) the pressure observed at its location

(c) the speed at which it is moving

(d) cloud cover at its location

(e) its dew point temperature

23. Advection is occurring at

(a) A

(b) B

(c) C

(d) D

(e) None of the locations indicated.

Questions 24 through 27 Refer to Figure 6, below.

24. The lines drawn on Figure 6 are

(a) isobars of sea surface temperature.

(b) contours of sea elevation

(c) isotherms of sea surface temperature.

(d) streamlines.

(e) radar depiction contours.

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Fig 6. Sea-surface Temperature Analysis for 20 September 2016

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25. Of the locations shown, the coldest ocean temperatures are occurring roughly at

(a) A

(b) B

(c) C

(d) D

(e) E

26. The location where hurricanes moving northwest from the Gulf of Tehuantepec would begin

weakening is best estimated by the letter

(a) A

(b) B

(c) C

(d) D

(e) E

27. The arrow shows the location of

(a) the California Current

(b) the Kuroshio Current

(c) the Humboldt Current

(d) the Gulf Stream

(e) the Polar Jet Stream

Questions 28 through 39 refer to Fig. 7 below.

Part V. Summer Sea level Pressure Patterns.

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Fig. 7, Mean Sealevel Pressure Map for July (larger version at back of exam)

28. Note the locations A, B and C. Of these locations, one records a wind speed of 15 knots, one a

wind speed of 30 knots and the other a wind speed of 20 knots. Which is recording 30 knots?

(a) A

(b) B

(c) C

29. Note the locations A, B and C. Of these locations, one records a wind speed of 15 knots, one a

wind speed of 30 knots and the other a wind speed of 20 knots. Which is reporting 15 knots?

(a) A

(b) B

(c) C

30. Note the locations A, B and C. Of these locations, one records a wind speed of 15 knots, one a wind

speed of 30 knots and the other a wind speed of 20 knots. Which is reporting 20 knots?

(a) A

(b) B

(c) C

31. Note the locations A, B and C. Of these locations, one records a south-southwest wind, one records a

west-northwest wind and one records an east-southeast wind. Which is reporting a east-southeast wind.?

(a) A

(b) B

(c) C

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32. Note the locations A, B and C. Of these locations, one records a south-southwest wind, one records a

west-northwest wind and one records an east-southeast wind. Which is reporting a south-southwest wind.?

(a) A

(b) B

(c) C

33. . Note the locations A, B and C. Of these locations, one records a south-southwest wind, one records a

west-northwest wind and one records an east-southeast wind. Which is reporting a west-northwest wind.?

(a) A

(b) B

(c) C

Below find the choices for questions (34), (35) and (36)

For questions (34), (35) and (36) choose from the choices above and try to estimate the locations of these

stations on Fig. 7.

34. At location A on the weather map, the correct wind plot would be

(a)

(b)

(c)

(d)

(e)

35. At location B on the weather map, the correct wind plot would be

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(a)

(b)

(c)

(d)

(e)

36. At location C on the weather map, the correct wind plot would be

(a)

(b)

(c)

(d)

(e)

37. High 1 is the

(a) California High

(b) Atlantic High

(c) Humboldt High

(d) Pacific High

(e) Bermuda High

38. The term “advection” in “advection fog” refers to the fact

(a) that vertical air currents produce fog.

(b) that air motions associated with the production of fog are swift.

(c) that the dew points associated with fog are in the 50s F.

(d) that horizontal motion brings air from the west to east over the cold California current,

where that air is cooled to the dew point.

(e) that the coastal fog is chiefly a summer phenomenon.

39. High 2 is the

(a) California High

(b) Atlantic High

(c) Humboldt High

(d) Pacific High

(e) Bermuda High

Part VI. Dew Point Temperature.

40. The dew point temperature is used by meteorologists in many ways. Which of the following is

NOT one of those ways?

(a) The dew point temperatures can be used as a rough indication of how much water vapor is

present.

(b) The difference between the actual temperature and the dew point temperature is related to the

relative humidity.

(c) Meteorologists can use the dew point temperature to determine how much cooling is needed to

produce clouds at the observation site..

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(d) Meteorologists use the dew point temperature to assess the strength of cyclones.

(e) The surface dew point temperature can be used as a very rough indicator of how prone the

atmosphere is for thunderstorm formation.

41. When the temperature is cooled to the dew point temperature at the ground

(a) condensation begins, often evidenced by the formation of fog.

(b) there is much water vapor in the air.

(c) strong winds develop.

(d) evaporation begins.

(e) rain occurs.

Part VII. 500 mb chart. (Questions 42 and 43 refer to Fig. 8 below)

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Figure 8. 500 mb chart With Possible Polar Jet Stream Positions, 12 UTC 24 September 2014

42. On Fig. 8, the correct location of the Polar Jet Stream is indicated by the arrow labeled.

(a) A

(b) B

(c) C

(d) D

(e) E

43. The conditions shown on Figure 8 are occurring roughly at an elevation of

a. 180 feet

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b. 1800 feet

c. 18000 feet

d. 180000 feet

e. 30000 feet

Part VII. Grab Bag

44. 80% of the atmosphere’s mass lies in the

(a) lowest 2 km (6000 ft) of the atmosphere.

(b) lowest 8 km (24000 ft) of the atmosphere.

(c) lowest 6 km (18000 ft) of the atmosphere.

(d) lowest 32 km (72000 ft) of the atmosphere.

(e) lowest 12 km (36000 ft) of the atmosphere.

45. California’s precipitation pattern is strongly influenced by topography.

(a) T

(b) F

46. San Francisco’s normal annual rainfall is most nearly

(a) 42 inches

(b) 32 inches

(c) 24 inches

(d) 12 inches

(e) 2 inches

47. Which statement is correct?

(a) In the absence of other effects, on a level surface, regions of higher pressure

move towards regions of lower pressure.

(b) Air moves fastest where isobars are furthest apart.

(c) Air motion at 500 mb tends to be slower than air motion at the surface.

(d) In the absence of other effects, on a level surface, air tends to move from regions of higher

pressure to regions of lower pressure.

(e) warm ocean currents

48. The pressure at the Tropopause is most nearly

(a) 100 mb

(b) 200 mb

(c) 300 mb

(d) 400 mb

(e) 500 mb

49. Eureka is located

(a) in the Sierra Nevada

(b) in the North Coast

(c) near Lake Tahoe

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(d) tin he South Coast

(e) just north of Santa Barbara

50. Normal annual rainfall is defined as

(a) the rainfall that should be expected each year.

(b) the rainfall that would occur only in a typical years and not other years.

(c) the average rainfall for the entire period of record.

(d) the rainfall that occurs normally in December, January, February.

(e) defined as the average rainfall for the thirty years ending the last even decade.