1 / 65

Meteorology Part 2: Weather Variables

Meteorology Part 2: Weather Variables. Earth Science Golodolinski/Black 2009. Part II: Weather Variables. Temperature Air Pressure Relative Humidity. Weather Variables. 1. Temperatures The measure of the average kinetic energy How fast the molecules move

eterri
Download Presentation

Meteorology Part 2: Weather Variables

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Meteorology Part 2:Weather Variables Earth Science Golodolinski/Black 2009

  2. Part II: Weather Variables • Temperature • Air Pressure • Relative Humidity

  3. Weather Variables • 1. Temperatures • The measure of the average kinetic energy • How fast the molecules move • Instrument used to measure temperature: • Thermometer • ESRT: Temperature conversion chart on p. 13

  4. 1. Temperatures • Shown on a weather map with: • Isotherms- Lines that connect places of equal temperature

  5. ESRT: Temperature conversion chart on p. 13& Chart Blank p. 183

  6. ESRT: Temperature Conversion Chart on p. 13Chart Answers p. 183

  7. ESRT: Temperature Conversion Chart on p. 13Temperature Chart Blank p. 183

  8. ESRT: Temperature Conversion Chart on p. 13Temperature Chart Answers p. 183

  9. Weather Variables 2. Air Pressure • The weight of Earth’s Atmosphere • Changes depending on the temperature • Instrument used to measure pressure: • Barometer • Measured in inches and milibars

  10. 2. Air Pressure • Shown on a weather map with: • Isobars- Lines that connect places of equal barometric pressures

  11. 2. Air Pressure • Mercury barometer • As the air pressure pushes on the surface of the mercury in the dish, the mercury travels up the tube. • As pressure increases, the mercury rises in the tube. • Cool air sinks- causes higher pressure • As the pressure decreases, the mercury sinks out of the tube. • Warm air rises- causes lower pressure

  12. ESRT: Pressure Conversion Chart p. 13

  13. ESRT: Pressure Conversion Chart p. 13Blank Chart p. 184

  14. ESRT: Pressure Conversion Chart p. 13Answer Chart p. 184

  15. 2. Air Pressure • State the relationship between altitude and air pressure. • As the altitude increases, the pressure decreases • Draw the relationship on the graph.

  16. Weather Variables 3. Relative Humidity • A ratio between the amount of moisture is in the atmosphere and how much moisture the atmosphere can hold • Measured in % • When the air is holding as much water vapor as it can, the air is saturated. When saturated, warm air contains more water vapor than cold saturated air. • When the air is saturated, the relative humidity is 100% To summarize, when the water-vapor content of air remains constant, lowering air temperature causes an increase in relative humidity, and raising air temperature causes a decrease in relative humidity.

  17. 3. Relative Humidity • Temperature & Relative Humidity • The warmer the temperature is, the more moisture it can hold • State the relationship between temperature and relative humidity: • As the temperature increases, relative humidity decreases • Draw the relationship on the graph.

  18. 3. Relative Humidity- Insturements

  19. 3. Relative Humidity • Dew Point Temperature • The temperature in which the air is saturated • 100% relative humidity

  20. Determining Relative Humidity and Dew Point Temperatures • Dry bulb • Air temperature • Wet bulb • Temperature an air parcel cooled by evaporation of water (wet cloth) • When given the wet bulb and dry bulb temperatures, you can determine the dew point temperature and relative by follow directions provided and using ESRT p. 12

  21. ESRT: Dew Point Temp. p. 12

  22. ESRT: Relative Humidity p. 12

  23. Example 1 p. 186

  24. Example 2 p. 186 p. 187 chart and #1-5

  25. Practice Dew Point & Relative Humidity p. 187

  26. Practice Dew Point & Relative Humidity p. 187 Answers

  27. Practice Dew Point & Relative Humidity p. 187 #1-5

  28. Condensation Gas to liquid Change of phase from water vapor (gas) to liquid vapor (water) Examples: Water on cold glass of water, water on mirror after a shower, dew on grass, fog, clouds Evaporation Liquid to gas

  29. 3 Things Needed for Condensation to Occur • Water vapor must be present • Air must be separated (relative humidity 100%) • Condensation nuclei (ex. dust particles)

  30. Density of Air • Warm air rises because it is less dense • Cold air sinks because it is more dense

  31. Formation of Clouds • Warm moist air rises • Air expands and cools due to the dew point • Air becomes saturated • Water droplets form on dust particles • Clouds consist of water droplets and ice crystals

  32. Cloud Classification

  33. Adiabatic Cooling • The cooling of a parcel of air as it rises through the atmosphere • Dry adiabatic lapse rate • rate of cooling or heating that applies only to unsaturated air. • dry air cools faster • Wet adiabatic lapse rate • rate of adiabatic temperature change in saturated air. • moist air cools slower

  34. Cloud Formation by Adiabatic Cooling

  35. Precipitation • Cloud particles (any form of water) too heavy to remain suspended in the air fall to Earth from a cloud • Examples: rain, hail, sleet, snow, freezing rain • What does precipitation do for the environment? • Cleans the air • ESRT p. 13 Present Weather

  36. Forms of Precipitation • The type of precipitation that reaches Earth’s surface depends on the temperature profile in the lower few kilometers of the atmosphere. • Rain & Snow • In meteorology, the term rainmeans drops of water that fall from a cloud and have a diameter of at least 0.5 mm. • At very low temperatures (when the moisture content of air is low) light fluffy snow made up of individual six-sided ice crystals forms. • Sleet is the fall of clear-to-translucent ice. • Hail is produced in cumulonimbus clouds.

  37. ESRT p. 13 Present Weather

  38. Wind • The horizontal movement of air • Caused by the uneven heating of Earth’s surface • Differences in air temperature cause differences in air pressure • The greater the difference in air pressure, the faster the wind

  39. Wind • Named by the direction in which they come from • Ex. North wind comes from the North • Isobars • Connect places of equal barometric pressure on a weather map

  40. Anemometer Measures wind speed Wind vane Determines wind direction Wind Instruments

  41. Water heats up slower than land: High specific heat Cooler temperatures Air sinks *HIGH pressure* Land heats up faster than water: Low specific heat Warmer temperatures Air rises *LOW pressure* Sea Breeze

  42. Water cools down slower than land (stays warmer) High specific heat Warmer temperatures at night Air rises Land cools down faster than water Low specific heat Cooler temperatures at night Air sinks Land Breeze

  43. Sea and Land Breezes

  44. Coriolis Effect • The deflection of winds and ocean currents caused by the rotation of Earth • Deflection is to the right in the Northern Hemisphere and to the left in the Southern Hemisphere

  45. High Pressure Cool/ cold air Air sinks/ goes down Air moves outward Clockwise No clouds No precipitation Low Pressure Warm air Air rises Air moves inward Counter clockwise Clouds Precipitation likely Weather Factors Associated with Different Pressure Areas

  46. ESRT: Planetary Winds p. 14

  47. Planetary Winds p. 191 Weather Changes- adobe

  48. Weather Changes p. 191

  49. Weather Changes

  50. Air Masses • Large region of the atmosphere with uniform temperature and humidity • ESRT p. 13: Air Masses

More Related