1. Moon’s Motions

2. Part 1. Moon Phases Luminous Illuminated Moon Phases
Produces its own light (Sun, stars)
Illuminated
Seen by reflected light (moon, planets)
Moon Phases
Apparent changes in the shape of the moon (different parts are illuminated by the Sun)
Moon Lit Up

4. Part 1. Moon Phases Waxing Waning Synodic Month Moon “growing” in size
Light on RIGHT side
Waning
Moon “shrinking”
Light on LEFT side
Synodic Month
Time to complete the moon phase cycle
29.5 days

6. Part 2. Eclipses Solar Eclipse Eclipse of sun
Occurs ONLY during NEW moon

7. Part 2. Eclipses Lunar Eclipse Eclipse of moon
Occurs ONLY at FULL moon

9. Part 3. Moon Motions Time for Moon to Revolve = 27.3 days
Time for Moon to Rotate = 27.3 days
Rotation = Revolution, so same side of moon always faces the Earth
Moon Phase Cycle = 29 days (moon must catch up to the Earth)

10. Part 4. Tides Daily rise and fall of oceans
Caused by the pull of gravity of the moon AND the Sun
Moon has a greater effect since it is closer to the Earth

11. Part 4. Tides Spring Tide (nothing to do with season)
The highest high tide and lowest low tide occurs
Gives the maximum difference between high and low tides
Happens during new or full moon

13. Part 4. Tides Neap Tide Lowest high tide and highest low tide
Gives minimum difference between high and low tides
Happens during Quarter moons

16. Part 4. Tides
Time from one HIGH tide to the next HIGH tide is 12 hours and 26 minutes
There are about 2 High and 2 Low tides per day

17. Importance of Waves Shaping Coastlines Ecology Erode cliffs
Grind rock into sand
Ecology
Returns O2 to water
Stir up food for filter feeders

18. Tides The rhythmic rise and fall of the ocean’s water
High tide = rising, incoming tide, flow
Low tide = receding, outgoing tide, ebb
Slack tide = vertical movement stops

19. Tides are very long, slow waves
They have a wave period of 12 hours 25 min
Tidal day is 24 hours 50 min
NJ has 2 high and 2 low tides daily

20. What Causes Tides? 1. Gravitational pull of sun & moon on Earth
Moon closer, therefore > effect
Like magnet, pulls water away from surface = TIDAL BULGE

21. 2. Centripetal Forces
Bulge on opposite side because centr. force > pull of moon
Produced by motions of Earth, sun, & moon

22. Types of Tides Spring Tide
- Moon and sun are in direct line with one another
- Results in unusually high tidal range
Tidal Range = vertical distance between high & low tides
2x’s/month

23. Neap Tide sun and moon are at right angles
Pulls cancel each other out – causes a weak pull
unusually low tidal range
2 x’s / month

24. Spring vs. Neap Tides

25. Distance bet. Moon & Earth
Perigee Tides
Moon closest to earth, very high tides (causes flooding)
Apogee Tides
Moon farthest away from earth, very low tides

27. Types of Tides Continued
Diurnal Tides
1 high & 1 low / day
Parts of Gulf of Mexico and Asia
Semi-Diurnal Tides
2 high & 2 low / day
Atlantic coasts of North America and Europe
Mixed
2 high & 2 low / day (height varies)
Pacific coast

28. Importance of Tides Expose & submerge orgs
Circulate water in bays & estuaries
Circulates food, wastes, etc
Trigger spawning (grunion, horseshoe crab)

29. Currents What are currents? Causes - “Rivers” of circulating water
- Wind
- Rotating Earth
- Density Changes

31. Surface Ocean Currents
Broad, slow drifts; never cross equator
Wind generated; circular gyres

32. Coriolis Effect
- N. Hemis – clockwise; Right
- S. Hemis – counterclockwise; Left

33. Gulf Stream - N. Atlantic
- Brings warm water from equator north along east coast of N. A.
Sometimes form eddies – circulating water that pinches off from the current

34. IMPORTANCE OF SURF. CURRENTS
NAVIGATION
MIGRATION
WEATHER

35. Localized Surface Currents
Longshore Current.
Flows parallel to shore; move sediment

36. RIP CURRENT
- Caused by converging longshore currents
- Very dangerous ; Red Flag
- DO NOT fight rip current; swim parallel to shore to get out of channel

38. Deep Ocean Currents Flow beneath surface; cross equator
Separated from surface currents by boundary called a “Thermohaline” (diff in densities)
Move North to South

39. Importance Of Deep Currents
Upwelling
Brings deep water to surf.
Circulates nutrients up
Moves plankton & larvae