1. Convection, Global Winds, and Jet Stream
Explain the influence of convection, global winds and the jet stream on weather and
climatic conditions.

2. Forming Wind
Earth is mostly rock or land, with three-fourths of its surface covered by a relatively thin layer of water, the oceans.
These two areas strongly influence global wind systems.

3. Forming Wind
Uneven heating of Earth’s surface by the Sun causes some areas to be warmer than others.
This causes air pressure to be generally lower where air is heated.
Wind is the movement of air from an area of higher pressure to an area of lower pressure.
ALL winds are created by the uneven heating of the earth.

4. Heated Air
Areas of Earth receive different amounts of radiation from the Sun because Earth is curved.
High pressure
Low pressure
High pressure

5. Heated Air
This cold, denser air comes from the poles, which receive less radiation from the Sun, making air at the poles much cooler.
The resulting dense, high-pressure air sinks and moves along Earth’s surface.
The heated air at the equator is less dense, so it is displaced by denser, colder air, creating convection currents.

6. The Coriolis Effect
The rotation of Earth causes moving air and water to appear to turn to the right north of
the equator and to the left south of the equator.

7. The Coriolis Effect The flow of air (WIND) caused by:
Differences in the amount of solar radiation received on Earth’s surface
Coriolis effect
creates distinct wind patterns on Earth’s surface.
The Coriolis Effect is responsible for the rotation of large cyclones.

8. Doldrums: windless rainy zone around the equator.
Trade Winds: are b/w 0°-30° N and 0°-30° S winds start in the east and move to the west towards the equator.
Prevailing westerlies: are b/w 30°-60° N and 30°-60° S winds start in the west and move to the east towards the poles.
Polar easterlies: are b/w 60°-90° N and 60°-90° S winds start in the east and move to the west towards the equator.

9. In the picture Color the area of the doldrums orange
Using arrows draw the trade winds blue
Using arrows draw the prevailing westerlies red
Using arrows draw the polar easterlies green
Create a color key.

10. Winds in the Upper Troposphere
A quick moving ribbon of air that constantly changes position is called a jet stream.
Types of jet streams:
Polar jet stream
Subtropical jet stream

11. Winds in the Upper Troposphere
The jet stream moves faster in the winter because the difference between cold air and warm air is greater.
The jet stream helps move storms across the country.
Moves west to east: California to NC

12. Winds in the Upper Troposphere
The polar jet stream forms at the boundary of cold, dry polar air to the north and warmer, more moist air to the south.
In the Northern hemisphere the polar jet stream brings cold weather from the north.

13. Winds in the Upper Troposphere
Subtropical jet stream: In Northern Hemisphere: brings warm weather from the south
In Southern Hemisphere brings warm weather from the north

14. Winds in the Upper Troposphere

15. Ocean Currents
Thermal energy carried by ocean currents has a strong influence on climates around the world.
Currents flowing toward the equator bring cooler waters.
Currents flowing from the equator bring warmer waters.
Currents are caused by the sun’s heat, global wind patterns and rotation of the earth.

16. Gulf Stream
Surface current in North Atlantic Ocean
One of the strongest known currents
Starts at the tip of Florida and flows up the Eastern Coast of the US
Carries warmer water up to the British Isles creating warmer winters.

17. Gulf Stream causes extreme storms
As the Gulf Stream reaches Cape Hatteras, North Carolina the cold current that flows from the north separates it from the coast.
When the warm Gulf Stream waters from the south (Florida) combine with the cold winds a dense concentration of fog forms along with an immense heat transfer causing atmospheric storms to intensify in this region.

18. Section Check
Question 1
What results from the Coriolis effect?

19. Section Check
Moving air turns to the right in the northern hemisphere and to the left in the southern hemisphere as a result of the Coriolis effect.

20. Section Check
Question 2
Narrow belts of strong winds blowing near the top of the troposphere are __________.
A. arctic blasts
B. doldrums
C. El Niños
D. jet streams

21. Section Check
Answer
The answer is D. The jet stream moves faster in the winter because of the greater temperature difference between cold and warm air.

22. Section Check
Question
Which of these is created during the day when solar radiation warms the land more than the water?
A. jet stream
B. land breeze
C. polar stream
D. sea breeze

23. Section Check
Answer
The answer is D. Cooler air over the water flows toward the warmer air on land, creating a sea breeze.