1. Weather, Climate, Air Masses, and Global Winds
Weather and Climate
Weather, Climate, Air Masses, and Global Winds

2. WEATHER and Climate Vocabulary
jet stream
ocean currents
global winds
latitude
longitude
altitude
air mass
Gulf Stream
weather
climate

3. WEATHER VS. CLIMATE Weather Climate
The average weather conditions for an area over a long period of time are referred to as climate.
Latitude is one of the most important factors that determines a regions climate
Climate is different from weather
Weather
Climate

4. Patterns That Affect Temperature
Temperature is affected by latitude, altitude, distance from large bodies of water, and ocean currents.
Latitude areas near the equator are warmer than areas far from the equator because the sun’s rays hit Earth’s surface more directly at the equator than at the poles.
Tropical Zone
Polar Zone
Temperate Zone

5. Patterns That Affect Temperature (cont.)
Distance from Large Bodies of Water
Alaska is about twice the size of Texas. Factors influencing temperature, such as distance from large bodies of water, affect this big state in different ways.
Where are Juneau and Fairbanks located in relation to each other?
Which climate data do you think describe Juneau? Fairbanks?
Which city on the map do you think represents the set of data for City C? Why?

6. Patterns That Affect Temperature (cont.)
Areas along the coasts are influenced by ocean currents. Some ocean currents warm the air above it therefore bringing mild, humid air to certain areas that have mild, wet climates (usually high latitude areas). Cold currents can also affect weather patterns by bringing cool air.

7. Global Winds

8. Patterns That Affect Precipitation
The main factors that affect precipitation are prevailing winds, the presence of mountains, jet streams, and seasonal winds.
What happens to the humid air when it encounters the mountains?
Shade in the landscape below to show what the vegetation may look like on the windward and leeward sides of the mountain range.

9. Patterns That Affect Precipitation
Jet streams cause a strong “river” of strong winds high above the surface of the earth. Jet Streams are a narrow band of strong winds in the upper atmosphere.
Jet Streams are stronger in the winter, since the temperature difference at the front boundaries are greater during this time.

10. Patterns That Affect Precipitation
Jet Streams are narrow bands of high-speed winds. These winds blow west to east and occur along the boundary of warm and cold air masses.
Which arrow shows the polar jet stream on the diagram? Which arrow shows the subtropical jet stream?

11. AIR MASS
A large body of air throughout which temperature and moisture are similar.
EX:
Continental air mass: form over large landmasses
Maritime air mass: form over oceans
Tropical air mass: form over deserts of the southwestern U.S.
Polar Air Masses: form over ice and snow covered land.

12. Air Masses and Their Movements
Types of Air Masses
Air masses can be classified according to temperature and humidity.

13. Air Masses and Their Movements
North American Air Masses
Air masses can be warm or cold, and humid or dry.

14. Air Masses and Their Movements
Types of Fronts
What type of weather is brought by each front?
Warm Front
Cold Front
Occluded Front
Stationary Front

15. How can local winds effect weather and climate?
The unequal heating of Earth’s surface within a small area causes local winds.
Sea Breeze
Wind that moves from a large body of water to land
Land Breeze
The flow of air from land to a body of water
DEMO

16. LOCAL WINDS
Sea breeze: Cooler air that moves in toward the land again to replace the warm air that is rising. This air then moves inland from the water
Land breeze: Since land cools quicker than water, air over the warmer water rises and flows toward the cooler land where the air sinks.
Gizmo
Practice