1. Ocean-Air Interaction

2. Distribution of Solar Energy
Concentrated solar radiation at low latitudes
Solar radiation more diffuse at high latitudes

3. Oceanic Heat Flow High latitudes–more heat lost than gained
Low latitudes–more heat gained than lost

4. Density Variations in the Atmosphere
Convection cell – rising and sinking air
Warm air rises
Less dense
Cool air sinks
More dense
Moist air rises
Dry air sinks

5. Movement of the Atmosphere
Thick column of air at sea level
High surface pressure equal to 1 atmosphere
Air always flows from high to low pressure.
Wind – moving air

6. The Coriolis Effect
Deflects path of moving object from viewer’s perspective
To right in Northern Hemisphere
To left in Southern Hemisphere
Due to Earth’s rotation
Merry Go Round CE
Drawn CE

7. The Coriolis Effect Zero at equator Greatest at poles
Change in Earth’s rotating velocity with latitude
0 km/hour at poles
More than 1600 km/hour (1000 miles/hour) at equator

8. The Coriolis Effect
© 2011 Pearson Education, Inc.

9. Global Atmospheric Circulation
High pressure zones – descending air
Subtropical highs – 30 degrees latitude
Polar highs –90 degrees latitude
Clear skies
Low pressure zones – rising air
Equatorial low – equator
Subpolar lows – 60 degrees latitude
Overcast skies with lots of precipitation

11. Storms and Air Masses
Storms – disturbances with strong winds and precipitation
Air masses – large volumes of air with distinct properties

12. Ocean’s Climate Patterns
Open ocean’s climate regions are parallel to latitude lines.
These regions may be modified by surface ocean currents.

13. Ocean’s Climate Zones Equatorial Tropical Subtropical Rising air
Weak winds
Doldrums
Tropical
North and south of equatorial zone
Extend to Tropics of Cancer and Capricorn
Strong winds, little precipitation, rough seas
Subtropical
High pressure, descending air
Weak winds, sluggish currents

15. Ocean’s Climate Zones Temperate Subpolar Polar Strong westerly winds
Severe storms common
Subpolar
Extensive precipitation
Summer sea ice
Polar
High pressure
Sea ice most of the year

17. Ocean Circulation
Fig. CO7

18. Ocean currents Moving seawater Surface ocean currents
Transfer heat from warmer to cooler areas
Similar to pattern of major wind belts
Affect coastal climates
Deep ocean currents
Provide oxygen to deep sea
Affect marine life

19. Types of ocean currents
Surface currents
Wind-driven
Primarily horizontal motion
Deep currents
Driven by differences in density caused by differences in temperature and salinity
Vertical and horizontal motions

20. Ekman spiral
Surface currents move at angle to wind because of the coriolos effect.
Ekman spiral describes speed and direction of seawater flow at different depths
Each successive layer moves increasingly to right (N hemisphere)

21. Ocean currents and climate
Fig. 7.9

22. Gulf Stream Meanders or loops Warm-core rings Cold-core rings
Unique biological populations
Fig. 7.17b

23. Climate effects of North Atlantic surface currents
Gulf Stream warms East coast of U.S. and Northern Europe
North Atlantic and Norwegian Currents warm northwestern Europe
Labrador Current cools eastern Canada
Canary Current cools North Africa coast

25. Thermohaline circulation
Below the pycnocline
90% of all ocean water
Slow velocity
Movement caused by differences in density (temperature and salinity)
Cooler seawater denser
Saltier seawater denser

26. Thermohaline circulation
Originates in high latitude surface ocean
Cold surface seawater sinks at polar regions and moves towards the equator

27. Thermohaline circulation
Fig. 7.26