1. The Movement of Ocean Water
Currents

2. movement of ocean water that follows a regular pattern
Ocean Current
movement of ocean water that follows a regular pattern
influenced by:
weather
Earth’s rotation
position of continents

3. horizontal movement of ocean water caused by wind
Surface current
horizontal movement of ocean water caused by wind
occurs at or near ocean’s surface
controlled by:
global winds
Coriolis effect
continental deflections

4. Global Winds
winds that blow across Earth’s surface that create surface currents
different winds cause currents to flow in different directions

5. Coriolis Effect
Earth’s rotation causes wind and surface currents to move in a curved path

6. Continental Deflections
when surface currents meet continents, the currents deflect (change direction)

7. Taking Temperatures
warm-water currents begin near equator – carry warm water to other parts
cold-water begins close to poles – carry cold water to other parts

9. Deep Currents
stream-like movement of ocean water far below surface
not controlled by wind
forms where water density increases
density affected by: salinity and temp

10. Increasing Density
Increasing Salinity (Freezing)
cold air chills water, increases density, cold water sinks
when water freezes, salt gets squeezed out at surface and enters liquid below
increases density

11. Increasing Salinity (Evaporation)
warm climates, water evaporates, leaves salt behind
increases density, sinks to form deep current

13. Currents and Climate

14. Surface Currents Warm-Water
Currents that create warm climates in coastal areas that would otherwise be much cooler

15. Cold-Water
Keep coastal areas cooler than inland climate

16. Upwelling
Movement of deep, cold, and mineral-rich water to surface of the ocean
Nutrients support the growth of plankton and animals that eat plankton

17. Change in water temperature in the Pacific Ocean
El Niño
Effects of El Niño
Change in water temperature in the Pacific Ocean
Produces a warm current
Alters weather patterns
Causes disasters (flash floods, mudslides, droughts)
Prevents upwelling off the coast of South America

18. Important due to its effects on land and on organisms
Studying El Niño
La Niña
Important due to its effects on land and on organisms
Scientists use a network of buoys along the equator that record data
Cooler than normal temperatures in the Pacific ocean
La Niña
El Niño

19. Waves

20. Anatomy of a Wave Wave Crest Trough Made up of crests and troughs
Highest point of a wave
Lowest point of a wave

22. Wave Formation and Movement
Wave Movement
Most are formed when the wind blows and transfer its energy to the water
As wind blows, water particles move up and down in circular motion
The water itself stays behind

23. Specifics of Wave Movement
Wave speed
Wave Period
All waves travel at different speeds
Use an equation to calculate wave speed
Time between the passage of two wave crests (or troughs) at a fixed point w a v e p r i o d
(s) l n g t h
(m) = s
(m/s)

25. Types of Waves Deep-water waves Shallow-water waves
Move in water deeper than one half their wave-length
When deep-water waves interact with ocean floor

26. Shore Currents Undertow When waves crash on the beach head on
The water moved from this wave flows back into the ocean under the new incoming waves
Movement of water from a shore current moving back into the ocean
Pulls objects with the current

27. Longshore Currents
Travel near or parallel to the shore line
Form when waves hit the shore at an angle
Transport most of the sediment in beach environments

28. Break in the open ocean before reaching the shore
Open-ocean waves
Whitecaps
Form in the open ocean
2 Types
Whitecaps
Swells
White, foaming waves
Very steep crests
Break in the open ocean before reaching the shore

29. Swells
Tsunami
Rolling waves that move steadily across the ocean
Form when a large volume of ocean water is suddenly moved up or down
Caused by underwater earthquakes

30. Storm Surges
Local rises in sea level near the shore that are caused by strong winds from a storm
The storm blows water into a big pile under the storm
As the storm moves onto shore, so does the giant mass of water beneath it

32. Tides

33. The Lure of the Moon Tide Daily changes in the level of ocean water
How often a tide occurs and the difference in tide levels depend on the position of the moon as it travels around Earth

34. High Tides
Low Tides
When part of the ocean is facing the moon, the water there and on the opposite side of Earth bulges towards the moon
Water is taken from these areas to form high tides

36. Timing of tides
Occur at different times each day because Earth rotates quicker than the moon revolves around Earth

37. Tidal Variations The Sun Tidal Range Also effects tides
Combination of sun and moon position in relation to Earth causes tidal ranges
Differences in ocean levels at high and low tides

38. Spring Tide
Neap Tide
Largest daily tidal range
Occur during full and new moons
Sun, Moon, and Earth are aligned
Smallest daily tidal range
Occur during 1st and 3rd quarters of the moon
Sun, Moon, and Earth form a 90° angle

40. Tidal Bore
Occurs in coastal areas with narrow inlets
Body of water rushes up through a narrow bay, estuary, or river channel during the rise of a high tide
Causes a very sudden tidal rise

41. What is Climate?

42. Weather
Climate
daily conditions of the atmosphere
temp, wind, precipitation, humidity vary day to day
average weather conditions in an area over time

43. Latitude
Solar Energy
distance north of south from equator
energy from the sun
hits most directly at the equator; most indirectly at the poles

44. Seasons
seasons change due to the tilt of the Earth’s axis
tilt affects how much solar energy an area receives
near equator and poles have little to no seasonal change

46. Prevailing Winds
Mountains
winds that blow mainly from one direction
affects precipitation in areas
affects both temperature and precipitation of areas on either side of mountain

47. Large Bodies of water
Ocean Currents
affects an area’s climate
water absorbs and releases heat slower than land
helps to moderate temp of land around it
surface currents carry warm or cool water to coastal areas

49. large zone characterized by climate, types of plants and animals
Climate Zones
Biome
three major zones:
tropical
temperate
polar
large zone characterized by climate, types of plants and animals

51. Changes in Climate Ice Age Volcanic Eruptions
long period of climate cooling
ice covered large areas of land
creates shield or dust and ash that block’s sun’s rays and cools climate

53. Asteroid Impact
Sun’s Cycle
acts like a volcano…throws debris (dust) into air that blocks sun = cools climate
sun follows 11-year cycle
has periods of high and low radiation

54. Global Warming
Greenhouse Effect
gradual increase in average global temp
natural process
warming of planet due to gases in atmosphere
essential for maintaining temp on surface

55. Greenhouse Effect
human activities increase gases
gases trap and hold more heat
result: warmer planet and climate changes
carbon dioxide: main contributor to climate change
major greenhouse gases: carbon dioxide, water vapor, methane, nitrous oxide

56. Consequences of global warming
positive impacts
longer growing seasons
more comfortable climates in cold areas
fewer cold-related deaths

57. negative impacts
rising sea levels (due to melting ice) causing loss of land
more severe weather (hurricanes, tornados, floods, droughts)
species extinction; species unable to adapt to climate changes