1. Water in the Atmosphere

3. Hydrological(Water) Cycle

4. Hydrological Cycle vocabulary Evaporation: the process of converting a liquid to a gas Transpiration: process where plants absorb water through the roots and then give off water vapor through pores in their leaves Precipitation: any form of water that falls from a cloud to Earth’s surface(rain, snow, sleet, hail, glaze) Evapotranspiration: the rapid cycling of water vapor into the atmosphere by evaporation from Earth’s surface or by transpiration from plant leaves

5. Hydrological Cycle vocabulary Sublimation: conversion of a solid directly to a gas without passing through the liquid state Infiltration: movement of surface water into rock or soil through cracks and pores Percolation: the movement and filtering of fluids through porous materials.filtering

6. H 2 O exists in atmosphere in all three states of matter…

7. Solid: snow hail ice

8. Liquid: rain and cloud droplets

9. Gas: invisible H2OH2O vapor

10. H 2 O may change from one state to another:

11. Melting: from solid ice to liquid H 2 O

12. Freezing: liquid H 2 O to solid ice

13. Evaporation: from liquid H 2 O to H 2 O vapor

14. Condensation: from H 2 O vapor to liquid H 2 O

15. Sublimation: change from solid to H 2 O vapor Example: Dry ice

16. Deposition: process of water vapor turning directly into a solid Frost on a window pane

17. Phase Changes : Turn to page 505 and copy figure 2 into your notes.

19. Quick Check: Use the chart you drew to assist you. 1.Is energy lost or gained when a gas changes into a solid? 2.What is the above process called? 3. Name the process that occurs when ice cream absorbs 334 joules of energy? 4. Give an example of sublimation.

20. Atmospheric Moisture Invisible in the form of water vapor gas (only what we can’t see) Where does it come from? Insolation(energy from the sun) -- heats water *changing it into a gaseous state Warm air can hold much more water than cold air

21. Water vapor enters the atmosphere from the evaporation of water from oceans, lakes, marshes and glaciers

22. Humidity: water vapor in the air Described as a. Specific humidity b.relative humidity

23. Relative Humidity (The measure we encounter daily)  Measure of the amount of water vapor present in air relative to the maximum amount that the air can contain at a given temperature (%) –e.g. if relative humidity is 50%, then it contains 1/2 the amount of water vapor it could hold at a given temperature  Relative humidity decreases as temperature increases Temp. Increase, ability to hold water increases Then RH Decreases

24. Relative Humidity and Temperature Figure 4.7, p. 125

26. Relative humidity=specific humidity X 100 capacity (saturated)

27. Psychrometer: instruments used to measure relative humidity Works on principle that evaporation causes cooling 2 thermometers…wet- bulb and dry-bulb Readings show how dry the air is

28. Dew point: the temperature at which air is saturated with water vapor Dew, clouds, and fog forms If dew point is below freezing, frost will form

29. Dew Point Temperature As air is cooled it eventually becomes saturated (100% relative humidity) the temperature of saturation is called the dew point temperature If cooling continues, condensation begins and dew forms

30. Clouds: simply high fogs, mist, or haze Form when air above surface cools below dew point Shape depends on air movement that forms it:

31. -horizontal air movement = layers -vertical air movement = piles

32. Temperature above freezing – clouds drop water Temperature below freezing – clouds drop snow crystals

33. Three main cloud types:

34. CIRRUS: - thin, feathery, made of ice crystals - form at high altitudes - seen when weather is fair, but can mean rain or snow

35. STRATUS Low sheets or layers; gray and smooth Block out the sun Associated with rain and drizzle

36. CUMULUS Piled in thick, puffy masses Formed by vertically rising air currents Usually mean fair weather

37. Other cloud types:

38. Cirrostratus

39. Stratocumulus

40. Cirrocumulus

41. Altocumulus

42. Nimbostratus

43. Cumulonimbus: large cloud that produce LIGHTNING, THUNDER, HEAVY SHOWERS = Thunderstorms

44. Precipitation: Water that falls from the atmosphere to the earth Occurs when cloud droplets grow into drops heavy enough to fall to Earth

45. FORMS OF PRECIPITATION Drizzle: fine drops, very close together, fall slowly ….less than 0.5mm diameter Rain drops: larger, farther apart, fall faster… 0.5mm to 5mm diameter Snow: falls in clumps of six-sided crystals Sleet: pellets of ice tha fall to the ground when raindrops fall through freezing air

47. Hail: irregular balls or lumps made of layers of ice forms in cumulonimbus clouds-

48. Acid precipitation: acid drops that fall to the ground - contain nitrate and sulfate particles that come from burning fuels, volcanoes and cars

51. Rain gauge: instrument used to measure the amount of rainfall

52. Cloud seeding: method to cause an increase in precipitation

53. Condensation nuclei: suspended particles that provide the necessary surfaces for cloud forming condensation.