1. What’s the story?

2. Oceanic Water
What do you think affects ocean temperatures?
Horizontal and vertical spatial variations in the temperature and salinity of ocean water.

3. What affects ocean temperatures?
Latitude
Seasonal changes (tilt of the Earth)
Ocean depth
Salinity
Transfer of energy (through winds/ocean currents)

4. Annotate your map to show (1) global variations in sea surface temperatures (2) the impact of ocean currents (look at the differences on the East and West sides of the continents)
Horizontal spatial variations

5. Annotate your map to show (1) global variations in sea surface temperatures (2) the impact of ocean currents (look at the differences on the East and West sides of the continents)
Sea surface temperature varies according to latitude – it is much warmer nearer to equatorial regions than in the poles
On the Western sides of continents, the cooler waters from ocean currents can be seen intruding towards the equator. Similarly (if not quite so clearly), the warmer waters of ocean currents flowing from the equatorial regions can be seen on the eastern side of several continents)

6. Vertical spatial variations in ocean waters
Ocean water varies considerably with depth – two of the considerable variations are:
Temperature
Salinity (how salty the water is)

7. How does ocean water temperature change with depth?
Tasks:
Draw a sketch of the graph
Describe what happens to ocean water temperatures with increasing depth
Between summer and winter, the ocean temperature change varies quite significantly between m deep. Below this level the temperature decline is much slower.

8. Thermocline
Definition: the zone of rapid temperature change in a vertical body of water. In the oceans the boundary usually occurs between 200m and 800m.
Approx. 90% of ocean water is found below the thermocline. Generally the surface waters do not mix with the deeper layers.

9. As oceans get deeper... Temperature decreases BUT...
Salinity increases
Water density increases

10. How does ocean water salinity change with depth?
Halocline - the zone of rapid salinity change in a vertical body of water. In the oceans the boundary usually occurs between 200m and 800m which is in a similar region to the thermocline.

11. What is the relationship between temperature, salinity and water density in the oceans?
Cold water is denser than warm water +
Saltier water is also denser
Temperature decreases with depth
Salinity increases with depth =
An increase in water density as depth increases
High
Temperature
Low
Low
High
Salinity

12. How does ocean water density change with depth?
Pycnocline - the zone of rapid water density change in a vertical body of water. In the oceans the boundary usually occurs between 200m and 800m which is in a similar region to the thermocline and halocline.

13. A few things to note...
The changes are seen more sharply in tropical areas than in polar regions because the surface temperatures are warmer near the equator
At great depths there is very little change in temperature between the equator and the poles

14. Where in the world can you find...?
The warmest waters?
The coldest waters?
The saltiest waters?
The least salty water?
The water with the highest density?
The water with the lowest density?