Weather

1. Weather

2. Weather... You can’t see me, but you feel me, you can’t touch me, but I can touch you. I have been called the “Breathe of the Gods”, or the killer and giver of life, gentle and fierce, friendly and enemy, angry and happy. The Native Americans called me Moriah, and Snow Eater (Chinook). The Japanese call me Kaze and in Russia I am called Veter. I can shatter homes, or wake a child from a peaceful sleep or bring relief in times of need. I can spread the most dreaded diseases or bring a welcome freshness. What am I?

3. Weather is.... • The current state of the atmosphere...what is happening right now

4. Main points to remember as we learn about weather: • The sun warms the earth’s surface and therefore all the air above the surface • The earth is warmed most at the equator and least at the poles---why? • The air above land is warmed more quickly than air above water. • Warm air expands and rises, creating an area of low pressure; cold air is dense and sinks, creating an area of high pressure

5. All weather is a result of humidity, condensation and pressure.

6. Types of Air Masses Continental: dry Polar: cold Maritime: wetTropical: warm • continental polar (cP): cold & dry (Canada) • continentaltropical (cT): warm & dry (Mexico) • maritime polar (mP): cold & wet (north oceans) • maritimetropical (mT): warm & wet (south oceans)

7. Label on your map…

8. Air Mass • Warm air= expanding or rising air= leaves behind Low (L) pressure • Cold Air=sinking air= leaves an area of High (H) pressure

9. Weather Fronts… • Fronts - the boundary between 2 air masses

10. Warm Front This is the symbol on a map for a warm front • Warm Front: warm air slides over departing cold air. • Large bands of precipitation form

11. This is the symbol for a cold front Cold Fronts • Cold air pushes under a warm air mass. Warm air rises quickly. • Narrow bands of violent storms form

12. This is the weather map symbol for an occluded front Occluded Front • 2 air masses merge and force warm air between them to rise quickly. • Strong winds and heavy precipitation will occur

13. This is the weather map symbol for a stationary front Stationary Front • Warm or cold front stops moving. • Light wind and precipitation may occur across the front boundary

14. QUIZ TIME!!! • Get a scrap piece of paper and number 1-3

15. What type of front(s) do you see?

16. Answer… • Cold Front & Stationary Front

17. What type of front(s) do you see?

18. Answer… • Cold Front

19. What type of front(s) do you see?

20. Occluded Front • Warm Front • Cold Front

21. Reading a weather map • ISOBAR= connects areas of equal pressure BAR comes from BARometric pressure. • We measure wind pressure with a Barometer

22. Reading a weather map... • Isotherm: Connects areas of equal temperature; therm means temperature

23. Isotherms

24. Let’s practice…

25. Wind Movement • Uneven heating of the earth’s surface causes some areas to be warmer than others. • As we know, warm always follows cold to share it’s warmth. • When this happens in the atmosphere, wind happens!

26. What causes winds? • A wind is a horizontal movement of air from a area of high pressure to an area of low pressure • It is this difference in pressure that makes the air move=wind • Winds are measured by direction and speed • The anemometer is the tool we use to measure this • Wind chill=↑ cooling the wind causes

27. Local Winds • The land cools and heats faster than the ocean. • Water holds heat longer than land, and takes longer to heat or cool.

28. Sea Breeze • During the day, the land gets hotter faster than the water. The heated air rises, leaving behind an area of low pressure. Wind from the cooler sea blows in to take the place of that warmer air. • These happen during the day!

29. Land Breezes At night the lands cools off faster than the sea. Cool air sinks creating an area of high pressure. Wind blows from the land to the sea.

30. Temperature • Air temperature is shown in Fahrenheit degrees by the number to the upper left of the circle. 75

31. Pressure • Pressure—measured in mb (millibars)—is given by the number to the upper right of the circle 194

32. Dew Point Temperature • The dew point temperature in Fahrenheit degrees is shown to the lower leftof the circle. 57

33. Wind Direction and Speed • Wind direction is shown by an “arrow” going into the circle. The example shows wind blowing from the lower right, so this is a southeast wind. • Each long “feather” represents 10 mph and each short “feather 5, so the wind speed is 25 mph.

34. Cloud Cover • The amount of the circle that is filled in indicates how much of the sky is covered by clouds. • It may range from “clear” (left) to “overcast” (right).

35. “Present Weather” • When rain, snow, or other forms of precipitation, lightning, and special weather conditions exist, these are shown by symbols to the left of the circle between air temperature and dew point temperature rain showers thunderstorm * snow

36. Try to interpret this station model • Temperature: • Pressure: • Dew Point: • Clouds: • Wind: • Precipitation: • 76 o F • 138 mb • 55 o F • cloudy • from NE at 20 mph • rain

37. Weather Station (not on the TV)

38. Clouds • In order for clouds to form, air must be at its dew point (temperature at which air is saturated). Water vapor condenses on small particles called condensation nuclei. • Cirrus—light, thin, feathery (fair weather clouds) • Cumulus—puffy white clouds • Stratus—low gray clouds

39. Cloud Formation • Clouds form when water vapor condenses on dust & salt particles in the air • The temperature in which condensation begins is called the dew point

40. TYPES OF CLOUDS • Cirrus Clouds: wispy, feathery clouds Form only at high levels, therefore are made of ice crystals

41. Types of Clouds • Cumulus Clouds: are puffy white cotton ball looking clouds

42. Cumulonimbus Clouds • These are thunderstorm clouds • Brainpop

43. Types of Clouds • Stratus Clouds: clouds that form in flat layers- cover all or most of the sky and are low level clouds