Name: ANSWER KEY Date: Class:

Air Pressure, Wind, Air Masses and Fronts, and Storms – Study GuideStudy Guide Due – 3/27/18 Test – 3/28/18

AIR PRESSURE (Ch. 15 section 1 p. 449; Air Pressure and Wind Notes)

1. Define Air Pressure.Air pressure is the force exerted onto a surface by the weight of air.

2. Fill in the diagram below showing high pressure and low pressure. Identify what happens to temperature and density.

3. As altitude increases, pressure DECREASES.

WIND (Ch. 15 section 3 p. 458 – 463; Air Pressure and Wind Notes; Global Winds Diagram)

4. What causes wind? Wind forms from differences in air pressure. The greater the difference in pressure, the faster the wind. Wind goes from high pressure to low pressure.

5. Draw and label a sea breeze and a land breeze. Label the direction of the wind, high and low pressure, more and less dense air, and cool and warm temperatures.

6. Describe global winds. Use as many of the vocabulary words as possible in your description. Underline/highlight the words you use: high air pressure, low air pressure, more dense, less dense, rises, sinks, convection currents, 30o latitude, 60o latitude, equator, poles, more direct sunlight, less direct sunlight, difference in air pressure, Coriolis effect, warm temperature, cool temperature

Unequal heating of Earth’s surface and the Coriolis Effect create global winds. Air near the equator is warmer because it receives direct sunlight year round.

o Since it is warmer, it is less dense and will rise in the atmosphere. o The equator is a low-pressure zone due to the warmer temperatures and less-dense air.

Air near the poles is colder because the poles receive indirect sunlight. o Since the air is colder, it is more dense and will sink. o The poles are high-pressure zones due to the colder temperatures and denser air.

The rise and fall of air creates convection currents which move air due to differences in air pressure

HIGH Density

COOLER Temperature

LOW Density

WARMER Temperature

High pressure Low pressure

Sea Breeze Land Breeze

High Pressure

More Dense

Low Pressure

Less Dense

Low Pressure

Less Dense

High Pressure

More Dense

AIR MASSES and FRONTS (Ch. 16 section 2 p. 490 – 493; Air Mass Map and Weather Fronts Foldable)

7. What two factors determine the type of air mass that forms? TEMPERATURE AND HUMIDITY

8. Identify the air masses by their abbreviations:a. cP = CONTINENTAL POLAR

b. cT = CONTINENTAL TROPICAL

c. mP = MARITIME POLAR

d. mT = MARITIME TROPICAL

9. What is the difference between a maritime and a continental air mass? MARITIME FORMS OVER OCEANS (WET) AND

CONTINENTAL FORMS OVER LAND (DRY)

10. What is the difference between a polar and tropical air mass? POLAR FORMS NEAR THE POLES (COLD) AND TROPICAL FORMS NEAR THE EQUATOR (WARM)

11. Where would you find a continental polar air mass in North America? What type of weather would it bring? NORTHERN CANADA; IT WOULD BRING COLD, DRY AIR

Fill in the table below:

Front How does it form? What type of weather does it

bring?

Symbol Sketch

Cold Front

COLD AIR PUSHES WARM AIR UP

THUNDERSTORMS, HEAVY RAIN, OR

SNOW COOLER AND DRIER WEATHER

Warm Front

WARM AIR MOVES OVER COLD AIR;

GRADUALLY REPLACES COLD AIR

DRIZZLY RAIN FOLLOWED BY CLEAR

AND WARM WEATHER

Stationary Front

COLD AIR MASS MEETS A WARM AIR MASS; STAYS

IN THE SAME SPOT

MANY DAYS OF CLOUDY, WET

WEATHER

Occluded Front

WARM MASS CAUGHT BETWEEN TWO COLD MASSES

COOL TEMPERATURES;

LARGE AMOUNTS OF RAIN AND SNOW

STORMS (Ch. 16 section 3 p. 496 – 503; Notes)

Compare and Contrast Thunderstorms and Tornados – include information about pressure, air masses, and fronts

How are they alike?

Cold fronts Tornados usually form at the base of thunderstorms Unstable air Low pressure High humidity Rain, hail

How are they different?Tornadoes

• central US• Begin as thunderstorms

that form supercells• winds blow in opposite

directions; if it touches the ground, it becomes a tornado

• High winds - rotation• Funnel cloud

Thunderstorms Thunder Lightning

HurricanesAnswer the following question. Use evidence from class to answer. “Many climate scientists predict that severe storms like hurricanes will intensify and be more destructive as global warming occurs. Why is this?”

Explanations will vary Should include:

o Hurricanes form over oceanso Need warm, moist airo Low pressureo Global warming = warmer ocean

temps = more hurricanes