Guided Notes Weather. Part 1: Weather Factors Temperature Humidity Air Pressure Winds Station Models

Transcription

1 Guided Notes Weather Part 1: Weather Factors Temperature Humidity Air Pressure Winds Station Models.

2 1. What is weather? Weather: short-term atmospheric conditions in a specific area at a specific time

3 2. Where does weather occur? Most weather changes occur in the troposphere (atmosphere just above Earth s surface) because this layer contains most of the water vapor.

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5 3. What are the factors that affect the weather? Temperature, humidity, air pressure, and winds affect the weather. These factors are all interrelated: when one factor changes, one or more of the other factors change.

6 WEATHER FACTOR #1: TEMPERATURE

7 4. How is temperature measured? Temperature: the measurement of the average kinetic energy of a substance.

8 4. How is temperature measured? othermometer: sealed glass tube marked with graduations and having at one end a bulb containing mercury or alcohol that expands and contracts in the tube with heating and cooling

9 4. How is temperature measured? o There are three major temperature scales used around the world. Most of the world uses Celsius scale, but in the U.S. people still use the Fahrenheit scale. People who work in scientific fields use Celsius or Kelvin scales. See Temperature scale conversions on ESRT page 13

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11 Each line = 2 F Each line = 1 C Each line = 1K.

12 4. How is temperature measured? Practice - Temperature Scales & Conversions: Use the temperature scales on ESRT page 13 to determine the temperatures listed below in Fahrenheit, Celsius, and Kelvin. Room temperature Water freezes Water boils F C K

13 5. How is temperature modeled on maps? Isotherms: isolines that are used to connect equal temperatures

14 5. How is temperature modeled on maps?

15 5. How is temperature modeled on maps? Practice - Drawing Isotherms: The map below is a map of the United States which shows recorded temperatures in degrees Fahrenheit for October 2, On the map below, draw the 30, 40, 50, 60, 70 and 80 F isotherm. Extend the isotherm to the edges of the continent..

16 6. How does temperature affect density? As temperature increases, density decreases. This causes warm air to rise and cold air to sink. Warm air Cold air

17 7. How does altitude affect temperature? Altitude: height above sea level

18 7. How does altitude affect temperature? As altitude increases in the troposphere, temperature decreases because the air gets thinner. (see ESRT page 14)

19 7. How does altitude affect temperature?

20 WEATHER FACTOR #2: HUMIDITY

21 8. What is humidity? Humidity: the amount of water in the air

22 9. How much moisture can the air hold? Moisture capacity: the amount of water that the air could hold o Warm air could hold more moisture than cold air because warm air has more space between the particles: Key = Dry air = Water vapor Cold temperatures Warm temperatures

23 10. How much moisture is in the air? Relative humidity: the amount of water in the air compared to how much water it could hold (expressed as a percentage) o 100% relative humidity means the air is saturated (full of water) and precipitation is likely.

24 11. How can relative humidity be modeled in the classroom? Modeling Humidity: The beakers below represent different air temperatures and the amount of water each air temperature could hold. You have 50 ml of water. Hot 20% Humidity Warm 50% Humidity Cool 100% Humidity Cold 100% Humidity & Precipitation

25 12. How do clouds form? When a parcel of warm air rises, it expands and cools to the dew point temperature to form a cloud. o Dew point temperature: the temperature that air must be cooled to be saturated

26 12. How do clouds form? When air temperature is equal to the dew point temperature: 1) Relative humidity equals 100%, 2) Water vapor will condense (form clouds), 3) Precipitation will occur.

27 12. How do clouds form? For condensation to occur, a solid surface is needed. Condensation nuclei (dust) in the atmosphere provide solid surfaces for condensation..

28 Practice Cloud Formation 1. Clouds usually form when a. air temperature reaches the dewpoint b. evaporation has warmed the surrounding air c. relative humidity is 0% d. condensation nuclei have been removed from the air

29 Practice Cloud Formation 2. In which sample will condensation most likely occur?

30 Practice Cloud Formation & Precipitation Base your answers to questions 3 through 5 on the atmospheric cross section below, which represents a winter storm system. Zones A, B, C, and D are located on a west to east line at approximately 43 N latitude across New York State. This cross section shows how solid and liquid forms of precipitation depend on the air temperature above Earth s surface. The storm is moving from west to east. 3. Explain why sleet is occurring in Zone B. The rain freezes as it falls through colder air before it hits the ground..

31 Practice Cloud Formation& Precipitation Base your answers to questions 3 through 5 on the atmospheric cross section below, which represents a winter storm system. Zones A, B, C, and D are located on a west to east line at approximately 43 N latitude across New York State. This cross section shows how solid and liquid forms of precipitation depend on the air temperature above Earth s surface. The storm is moving from west to east. 4. As the storm moves eastward, the type of precipitation received in Syracuse changes. State the type of precipitation that will immediately follow freezing rain..

32 Practice Cloud Formation& Precipitation Base your answers to questions 3 through 5 on the atmospheric cross section below, which represents a winter storm system. Zones A, B, C, and D are located on a west to east line at approximately 43 N latitude across New York State. This cross section shows how solid and liquid forms of precipitation depend on the air temperature above Earth s surface. The storm is moving from west to east. 5. Describe the general air movement and temperature change that caused the clouds associated with this storm to form..

33 13. Why are there different forms of precipitation? Rain

34 13. Why are there different forms of precipitation? Drizzle Falling liquid drops from 0.2 mm to 0.5 mm in diameter

35 Drizzle

36 13. Why are there different forms of precipitation? Snow Falling ice crystals formed by combining cloud ice crystals

37 Snow

38 13. Why are there different forms of precipitation? Sleet Solid pellets of ice that form by freezing of rain drops as they fall

39 Sleet.

40 13. Why are there different forms of precipitation? Freezing Rain Rain or drizzle that freezes on contact with features of Earth s surface

41 Freezing Rain

42 13. Why are there different forms of precipitation? Hail Layers of ice, snow, and water formed by many up-and-down movements in thunderstorm clouds

43 Hail.

44 14. How is humidity measured? To measure humidity, you use an instrument called a sling psychrometer which is has two thermometers: Wet cloth! o Dry bulb thermometer: measures normal air temperature o Wet bulb thermometer: has a wet cloth on the bulb which causes the thermometers temperature to lower due to the cooling effect of evaporation

45 Sling Psychrometer

46 Using a Sling Psychrometer

47 14. How is humidity measured? After taking measurements, use charts on ESRT page 12: Dew Point ( C) & Relative Humidity (%): o Top row: Difference between wet-bulb and drybulb temperature (Subtract these two temperatures) o Left column: Dry-bulb temperature ( C) o Find where the correct row and column meet.

48 14. What is the relationship between air temperature, dew point temperature & relative humidity? Numerical Example: Determine the dew point temperature and relative humidity for each location. Location Dry-Bulb Temperature ( C) Wet-Bulb Temperature ( C) Difference (Dry Wet) ( C) Dew Point Temperature ( C) Relative Humidity A C B C D E

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50 14. What is the relationship between air temperature, dew point temperature & relative humidity? Conclusion: 1. The closer the air temperature and dew point, the higher the relative humidity. 2. The further the air temperature and dew point, the lower the relative humidity.

51 14. What is the relationship between air temperature, dew point temperature & relative humidity? Sling Psychrometer Example: Base your answers to the questions 3 and 4 below on the diagram below which shows drybulb and wet-bulb temperature readings for a parcel of air. 3. Based on the readings, what is the dewpoint of the air?

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53 14. What is the relationship between air temperature, dew point temperature & relative humidity? Sling Psychrometer Example: Base your answers to the questions 3 and 4 below on the diagram below which shows drybulb and wet-bulb temperature readings for a parcel of air. 3. Based on the readings, what is the dewpoint of the air?

54 14. What is the relationship between air temperature, dew point temperature & relative humidity? Sling Psychrometer Example: Base your answers to the questions 3 and 4 below on the diagram below which shows drybulb and wet-bulb temperature readings for a parcel of air. 4. Based on the readings, what is the relative humidity of the air?

55 14. What is the relationship between air temperature, dew point temperature & relative humidity? Sling Psychrometer Example: Base your answers to the questions 3 and 4 below on the diagram below which shows drybulb and wet-bulb temperature readings for a parcel of air. 4. Based on the readings, what is the relative humidity of the air?

56 14. What is the relationship between air temperature, dew point temperature & relative humidity? Graphing Example: Use the graph below to answer the following questions. 5. What time of the day is relative humidity highest?

57 14. What is the relationship between air temperature, dew point temperature & relative humidity? Graphing Example: Use the graph below to answer the following questions. 6. What time of day is the relative humidity lowest?

58 14. What is the relationship between air temperature, dew point temperature & relative humidity? Graphing Example: Use the graph below to answer the following questions. 7. What is the relative humidity when the air temperature and dew point are equal?

59 14. What is the relationship between air temperature, dew point temperature & relative humidity? Graphing Example: Use the graph below to answer the following questions. 8. What is the relative humidity when the air temperature and dew point are farthest apart?

60 14. What is the relationship between air temperature, dew point temperature & relative humidity? Graphing Example: Use the graph below to answer the following questions. 9. What time of the day is precipitation most likely? Explain your answer.

61 14. What is the relationship between air temperature, dew point temperature & relative humidity? Graphing Example: Use the graph below to answer the following questions. 10. What time of the day is the most evaporation occurring? Explain your answer.

62 14. What is the relationship between air temperature, dew point temperature & relative humidity? Conclusion: o When the relative humidity is highest, air temperature and dew point are closest together. Precipitation is most likely to occur at this time.

63 WEATHER FACTOR #3: AIR PRESSURE

64 15. What is air pressure? Air pressure (also known as atmospheric pressure or barometric pressure): measurement of the weight of the gases pushing on Earth s surface o High pressure: a lot of gases are pushing on Earth o Low pressure: less gases are pushing on Earth

65 TED-ED: How Heavy is Air?

66 16. What factors affect air pressure? 1) Temperature: as temperature increases, air pressure decreases. o Cold air = more dense and sinks = high air pressure o Warm air = less dense and rises = low air pressure

67 16. What factors affect air pressure? 2) Humidity: as humidity increases, the air pressure decreases. o Dry air = more dense and sinks = high air pressure. o Humid air = less dense and rises = low air pressure

68 Weight of the Air

69 16. What factors affect air pressure? 3) Altitude: as your altitude increases, the air pressure decreases. (less air molecules) o Low pressure air movement: When warm, moist air rises, the air expands and cools to the dewpoint temperature which forms clouds. o High pressure air movement: When cool, dry air sinks, the air contracts and warms which does not allow clouds to form.

70 Air Pressure & Altitude

71 17. How is air pressure measured? Barometer: an instrument used to measure air pressure

72 17. How is air pressure measured? o Mercury barometer: a tube with a closed top is placed in a container of mercury. When air pushes down on the mercury in the container, the mercury rises in the tube. The height is measured in inches of mercury.

73 Mercury Barometer

74 17. How is air pressure measured? o Aneroid barometer: metal can that contains a partial vacuum that expands and contracts with changes in air pressure, and a series of mechanical parts display a reading on a dial.

75 Aneroid Barometer.

76 TED-ED: The history of the barometer (and how it works)

77 18. How can inches of mercury be converted into millibars? Air pressures can be converted using ESRT page 13.

78 18. How can inches of mercury be converted into millibars? Each line = 1 millibar Each line = 0.01 inches.

79 18. How can inches of mercury be converted into millibars? Practice - Converting Air Pressures: Use ESRT page 13 Air Pressure to convert the following air pressures. Millibars mb mb mb mb mb mb Inches of Hg (Mercury) in in in in in in

80 19. How is air pressure modeled on a map? Isobars: isolines that connect points of equal air pressure at a 4 millibar interval.

81 19. How is air pressure modeled on a map?

82 20. What do changes in the air pressure indicate? Barometric trend: how the air pressure increases or decreases over time. Increasing pressure " Barometer increases o When air pressure is increasing (getting higher), clear weather is coming.

83 20. What do changes in the air pressure indicate? Decreasing pressure o When air pressure is decreasing (getting lower), stormy weather is coming. " Barometer decreases

84 Practice Air Pressure Practice 1. What is the average air pressure exerted by Earth's atmosphere at sea level, expressed in millibars and inches of mercury? a mb and in of Hg b mb and in of Hg c mb and in of Hg d mb and in of Hg

85 Practice Air Pressure Practice 2. As the temperature of the atmosphere at a given location increases, the air pressure will most likely a. decrease b. increase c. remain the same

86 Practice Air Pressure Practice 3. As warm, moist air moves into a region, barometric pressure readings in the region will generally a. decrease b. increase c. remain the same

87 Practice Air Pressure Practice 4. The table below shows the noontime data for air pressure and air temperature at a location over a period of one week. Based on the data provided, which air pressure would most likely occur at noon on November 15? a. 987 millibars c millibars b millibars d millibars

88 21. What is a pressure center? Pressure center: highest or lowest pressures on a weather map o Isobars form circles, or bulls-eyes, around the pressure centers..

89 22. What are the weather conditions associated with high pressure and low pressure centers? High Pressure System Weather Conditions: Cooler and Dry

90 22. What are the weather conditions associated with high pressure and low pressure centers? High Pressure System Surface winds circulate: Outwards and clockwise

91 22. What are the weather conditions associated with high pressure and low pressure centers? High Pressure System Vertical air movement: Sinking, diverging air H

92 Why is high pressure associated with fair weather?

93 22. What are the weather conditions associated with high pressure and low pressure centers? Low Pressure System Weather Conditions: Warmer and Wet (Lousy Low)

94 22. What are the weather conditions associated with high pressure and low pressure centers? Low Pressure System Surface winds circulate: Inward and counterclockwise.

95 22. What are the weather conditions associated with high pressure and low pressure centers? Low Pressure System Vertical air movement: Converging, rising air L

96 Looking at Lows.

97 Practice Isobars & Pressure Centers 1. Which map shows the most likely pattern of isobars associated with this weather system?

98 Practice Isobars & Pressure Centers 2. Which map view best represents the pattern of isobar values, in millibars, and the pattern of wind flow, shown by arrows, at Earth s surface surrounding a Northern Hemisphere low-pressure center?

99 Practice Isobars & Pressure Centers 3. Which map best represents the surface wind pattern around a Northern Hemisphere high-pressure center?

100 Practice Isobars & Pressure Centers 4. Which map shows the most likely location of clouds associated with these pressure centers?

101 Practice Isobars & Pressure Centers Base your answers to questions 5 through 9 on the map below which shows air pressures at different locations in the United State on a particular day. 5. On the map below, draw isobars for 988, 992, 996, 1000, and 1004 millibars..

102 Practice Isobars & Pressure Centers 6. Label the high pressure center with a capital H. H.

103 Practice Isobars & Pressure Centers 7. Label the low pressure center with a capital L. H L.

104 Practice Isobars & Pressure Centers 8. Draw 3 large arrows around the high pressure center indicating the wind direction. H L.

105 Practice Isobars & Pressure Centers 9. Draw 3 large arrows around the low pressure center indicating the wind direction. H L.

106 WEATHER FACTOR #4: WIND

107 23. Why does air move? Wind: horizontal movement of air caused by differences in air density due to the uneven heating of Earth s surface.

108 24. Which direction does the wind blow? Winds always flow from high pressure to low pressure. o Areas that are warm have low pressure. o Areas that are cool have high pressure.

109 24. Which direction does the wind blow? Practice Wind Direction & Speed: Air pressures for City A and City B are shown at noon on Monday and on Tuesday. Draw an arrow between the two cities to show the direction of the wind on each day. Determine which day the wind speed was greater. Explain your answer. High Pressure Cool Low Pressure Warm Forest

110 25. Which direction does the wind blow? Wind vane: an instrument that indicates the compass direction the wind is coming from Winds are always named for the direction they come from!

111 Wind Vane

112 25. Which direction does the wind blow? Practice - Determining Wind Direction: The arrow below shows the direction of wind movement. Name the wind indicated by the arrow on the diagrams below. N N N W E W E W E S S S South wind West wind Southwest wind

113 26. How fast does the wind blow? Wind speed depends the pressure gradient: o The greater the pressure gradient, the faster the wind blows. o The lower the pressure gradient, the slower the wind blows.

114 26. How fast does the wind blow? Practice Wind Direction & Speed: Air pressures for City A and City B are shown at noon on Monday and on Tuesday. Draw an arrow between the two cities to show the direction of the wind on each day. Determine which day the wind speed was greater. Explain your answer.

115 27. How is wind speed measured? Anemometer: instrument that measures the speed of the wind

116 Anemometer.

117 28. How is wind speed modeled on a map? Wind speed on a map can be determined by the distance between isobars.

118 28. How is wind speed modeled on a map? o The closer the isobars, the faster the wind is in that area. o The farther the isobars, the slower the wind is in that area..

119 Where is the fastest wind speed on this map?.

120 How is wind formed? Why is there more wind in some cities?

121 Practice - Winds 1. The diagram below represents a section of a weather map showing high- and low-pressure systems. The lines represent isobars. At which point is the windspeed greatest? 1) A 2) B 3) C 4) D

122 Practice - Winds 2. Winds blow from regions of 1. high air temperature to regions of low air temperature 2. high air pressure to regions of low air pressure 3. high precipitation to regions of low precipitation 4. convergence to regions of divergence

123 Practice - Winds 3. Wind velocity is most dependent upon 1 gradient of the air pressure field 2 moisture content of the air 3 value of the Coriolis Effect 4 rotational velocity of the Earth

124 Practice - Winds 4. The weather map below shows closely spaced isobars in the region of Albany, New York. At the time that the weather data were collected, Albany was most probably experiencing 1 a high wind velocity 2 a high temperature 3 the passage of a dry air mass 4 the passage of a warm air mass

125 Practice - Winds 5. As wind velocity increases, the distance between isobars on a weather map will 1 decrease 2 increase 3 remain the same

126 Practice - Winds 6. The diagram below shows weather instruments A and B. Which table correctly indicates the name of the weather instrument and the weather variable that it measures?.

127 Practice - Winds 7. The map below represents the center of a low pressure system indicated by the L. The 1000-millibar (mb) isobar is drawn around the center of this low pressure system. 1) On the map below, draw two additional isobars around the outside of the 1000-mb isobar in a way that indicates that the strongest winds are west of the low-pressure center. 2) Label the value of each isobar using a 4-millibar interval

128 Practice - Winds 7. The map below represents the center of a low pressure system indicated by the L. The 1000-millibar (mb) isobar is drawn around the center of this low pressure system. 3) Draw 3 large arrows around the low pressure center to indicate the direction the air is spinning

129 Practice - Winds 8. Use the maps and the map scale below to calculate the pressure gradient for each labeled area. 1) Predict which area will have the greater wind speed. Explain your prediction.

130 Practice - Winds 8. Use the maps and the map scale below to calculate the pressure gradient for each labeled area. 2) Calculate the pressure gradient in area A. Gradient = change in field value distance

131 Practice - Winds 8. Use the maps and the map scale below to calculate the pressure gradient for each labeled area. 3) Calculate the pressure gradient in area B. Gradient = change in field value distance

132 Practice - Winds 8. Use the maps and the map scale below to calculate the pressure gradient for each labeled area. 4) Which area had the faster wind speed? Did the calculations support your prediction?

133 Practice Weather Instruments Directions: Identify the name of each weather instrument shown below. State the weather variable this instrument is used to measure. a) Weather Instrument Diagram Name of Weather Instrument Variable Measured

134 Practice Weather Instruments Directions: Identify the name of each weather instrument shown below. State the weather variable this instrument is used to measure. b) Weather Instrument Diagram Name of Weather Instrument Variable Measured

135 Practice Weather Instruments Directions: Identify the name of each weather instrument shown below. State the weather variable this instrument is used to measure. c) Weather Instrument Diagram Name of Weather Instrument Variable Measured

136 Practice Weather Instruments Directions: Identify the name of each weather instrument shown below. State the weather variable this instrument is used to measure. d) Weather Instrument Diagram Name of Weather Instrument Variable Measured

137 Practice Weather Instruments Directions: Identify the name of each weather instrument shown below. State the weather variable this instrument is used to measure. e) Weather Instrument Diagram Name of Weather Instrument Variable Measured

138 Practice Weather Instruments Directions: Identify the name of each weather instrument shown below. State the weather variable this instrument is used to measure. f) Weather Instrument Diagram Name of Weather Instrument Variable Measured

139 29. How does specific heat of land vs. water affect winds? Coastal breezes: due to the difference in specific heats, land and water have different temperatures at different times of the day. Specific Heat Animation: oceanservice.noaa.gov/education/pd/ oceans_weather_climate/media/specific_heat.swf

140 29. How does specific heat of land vs. water affect winds? 1) Sea (ocean) breeze: during the day, the surface wind blows from the water towards the land. Cooler air over ocean = high pressure Warmer air over land = low pressure H Ocean Surface wind L Land

141 29. How does specific heat of land vs. water affect winds? 2) Land breeze: at night, the surface wind blows from the land towards the water. Warmer air over ocean = low pressure Cooler air over land = high pressure L Ocean Surface wind H Land

142 Sea Breeze & Land Breeze Video meteorology/weather_variables/ animations/sea_breeze.swf

143 29. How does specific heat of land vs. water affect winds? Monsoons: seasonal reversing of winds and precipitation patterns caused by large differences in temperature of the land and the ocean water in certain seasons.

144 Mumbai, India in Dry vs. Wet Season

145 29. How does specific heat of land vs. water affect winds? o Summer: heavy rains occur when moist wind flows from to ocean onto land. Low Pressure, Warmer High Pressure, Cooler

146 29. How does specific heat of land vs. water affect winds? o Winter: dry conditions occur when dry wind flows from the land to the ocean. High Pressure, Cooler Low Pressure, Warmer

147 Monsoons Not Just for India

148 Practice Coastal Breezes & Monsoons 1. Earth s surface winds generally blow from regions of higher a. air temperature toward regions of lower air temperature b. air pressure toward regions of lower air pressure c. latitudes toward regions of lower latitudes d. elevations toward regions of lower elevations

149 Practice Coastal Breezes & Monsoons 2. The circulation of air above Earth s surface at a coastal location during the day and at night is best described as an example of a. conduction between Earth s surface and the atmosphere above it b. condensation of water vapor during the day, and evaporation of water during the night c. convection resulting from temperature and pressure differences above land and water d. greater radiation from the warmer ocean during the day and from the warmer land at night

150 Practice Coastal Breezes & Monsoons 3. The cross section below shows a house on the shore of Lake Ontario in August. Under which conditions would the wind shown in the cross section most likely occur? a. at 2 a.m., when the air over land is 70 F and the air over the lake is 80 F b. at 6 a.m., when the air over land is 70 F and the air over the lake is 70 F c. at 2 p.m., when the air over land is 80 F and the air over the lake is 70 F d. at 10 p.m., when the air over land is 70 F and the air over the lake is 72 F

151 Practice Coastal Breezes & Monsoons 4. Which cross section below best shows the locations of high air pressure and low air pressure near a beach on a cool summer night?

152 Practice Coastal Breezes & Monsoons 5. The map below shows the location of India and the Indian Ocean. Which statement best describes the monsoon winds during the rainy season in India? a. Moist air flows from India to the Indian Ocean. b. Moist air flows from the Indian Ocean to India. c. Dry air flows from India to the Indian Ocean. d. Dry air flows from the Indian Ocean to India.

153 30. How can all of these weather factors be shown on a map at the same time?.

154 30. How can all of these weather factors be shown on a map at the same time? Station model: simple diagram that summarizes 10 pieces of weather information o A station model has no units!

155 30. How can all of these weather factors be shown on a map at the same time? Air Temperature: In degrees Fahrenheit Visibility: Distance you can see in miles Dewpoint Temperature: In degrees Fahrenheit Wind speed (knots): Total number of feathers Whole feather = 10 knots Half feather = 5 knots Present Weather: Type of precipitation occurring Cloud Cover: Percent of circle shaded in Wind direction: Stick points in direction wind is coming from Barometric Pressure: Air pressure abbreviated (Actual = mb) Barometric trend: Change in air pressure over past 3 hours (Actual +1.9mb) + or / = rising - or \ = falling Precipitation: Amount over the past 6 hours

156 30. How can all of these weather factors be shown on a map at the same time?

157 31. How is air pressure abbreviated on a station model? Barometric (air) pressure is a 3 digit abbreviation on the station model: 1) To convert actual air pressure to the abbreviation, take off the 9 or 10 in the front, remove decimal and remove units. Example A: mb = Example B: mb =

158 31. How can all of these weather factors be shown on a map at the same time? 2. To convert from abbreviation to actual air pressure: If the abbreviation is greater than 500, add a 9 to the front, a decimal between the last two numbers, and units (millibars). o Example: 870 =

159 31. How can all of these weather factors be shown on a map at the same time? 2. To convert from abbreviation to actual air pressure: If the abbreviation is less than 500, add 10 to the front, a decimal between the last two numbers, and units (millibars). o Example: 104 =

160 31. How can all of these weather factors be shown on a map at the same time? Practice - Station Model Air Pressure Abbreviations: Actual Air Pressure mb Station Model Abbreviation mb mb mb mb.

161 31. How can all of these weather factors be shown on a map at the same time? Practice - Station Model Air Pressure Abbreviations: Actual Air Pressure Station Model Abbreviation mb

162 Practice Station Model Practice 1) For Station 1, use the station model below to fill in the chart. Weather Factor Station 1 Station 2 Temperature Dew Point Barometric Pressure Wind Direction Wind Speed Precipitation Cloud Cover Barometric Trend Present Weather Visibility 52 F 46 F mb West 20 knots 0.30 inch 0% 1.4 mb increase None. 10+ miles

163 Practice Station Model Practice 2) For Station 2, use the station model below to fill in the chart Weather Factor Station 1 Station 2 Temperature ( o F) Dew Point ( o F) Barometric Pressure (mb) Wind Direction Wind Speed (knots) Precipitation (inches). 10+ miles 33 F 30 F mb Northeast 10 knots.50 inch Cloud Cover 100% Barometric Trend Present Weather Visibility (miles) 52 F 46 F mb West 20 knots 0.30 inch 0% 1.4 mb increase None 2.4 mb increase Sleet 1 mile

164 Practice Station Model Practice 3) Which station model above shows the highest relative humidity? Justify your answer. Station 2 because: The air temperature and the dewpoint temperature are close together The cloud cover is 100% There is precipitation occurring.

165 Practice Station Model Practice 4) Impossible Station Models Find the problem with each station model. Explain the error. a) Problem: 45 F F +30/ There are units for the temperature and dewpoint temperature..

166 Practice Station Model Practice 4) Impossible Station Models Find the problem with each station model. Explain the error. b) Problem: / The barometric pressure is not abbreviated..

167 Practice Station Model Practice 4) Impossible Station Models Find the problem with each station model. Explain the error. c) Problem: mb / The barometric pressure has units..

168 Practice Station Model Practice 4) Impossible Station Models Find the problem with each station model. Explain the error. d) Problem: \ The barometric trend is not abbreviated..

169 Practice Station Model Practice 4) Impossible Station Models Find the problem with each station model. Explain the error. e) Problem: / The air temperature is lower than the dewpoint temperature..