Midterm Weather

Question 1

Describe air movement

Answer 1

Warm air rises; cool air sinks.

Question 2

Why does warm air rise and cool air sink?

Answer 2

Warm, moist air is less dense than cold, dry air.

Question 3

Describe phase changes in climate

Answer 3

Require energy gain or loss (e.g., melting, freezing, evaporation, condensation).

Question 4

Explain what is required for a substance to undergo a phase change (weather)

Answer 4

For a substance to undergo a phase change, like in weather conditions, it needs to gain or lose energy (usually in the form of heat), which can be achieved by a change in temperature, and sometimes also a change in pressure, allowing the molecules to rearrange and transition between states like solid, liquid, and gas; examples include melting ice (solid to liquid), water evaporating (liquid to gas), or condensation forming on a cold surface (gas to liquid).

Question 5

Describe the most common phase changes (weather)

Answer 5

Evaporation: Liquid water turns into water vapor when it gains heat from the environment.

Condensation: Water vapor in the air turns back into liquid droplets when it loses heat, forming clouds.

Freezing: Liquid water turns into ice when it loses heat.

Melting: Ice turns into liquid water when it gains heat.

Sublimation: Ice directly changes into water vapor without going through the liquid phase (occurs in cold, dry environments).

Question 6

Describe what influences air pressure

Answer 6

Higher elevation = lower pressure.
Warmer temperature = lower pressure.
More humidity = lower pressure.

Question 7

How do clouds form?

Answer 7

Water vapor in the air condenses to form liquid water or ice crystals. Water vapor cools

Cirrus
Cumulus
Stratus

Question 8

What causes wind?

Answer 8

Caused by differences in air pressure; moves from high to low pressure.

Question 9

What direction does local wind always blow?

Answer 9

Generally, winds across most of the globe blow from west to east due to the Earth’s rotation and the Coriolis effect.

Question 10

What causes global wind patterns?

Answer 10

Air moves between equator and poles due to temperature differences. Global winds do not follow a straight path due to coriolis effect

Question 11

What are air masses?

Answer 11

Large bodies of air that have similar temperature, humidity, and air pressure

Question 12

What properties are used to describe an air mass?

Answer 12

An air mass is primarily described by its temperature and humidity properties, which are determined by the place where it forms;

Tropical: warm - forms over a warm ocean,
Polar: cold - forms north of 50 degrees north or south of 50 degrees south (polar regions)

Maritime: forms over oceans (humid)

Continental: forms over land (drier)

Question 13

What is Coriolis effect?

Answer 13

The effect of convection and Earth’s rotation causes global winds to have a swirling pattern

Question 14

What occurs when air masses interact?

Answer 14

Air fronts are large bodies of air with uniform temperature and humidity. When air masses meet, they cause storms and weather changes.

Question 15

What are the types of air fronts?

Answer 15

The four main types of air fronts arecold, warm, stationary, and occluded.

Question 16

Describe a cold air front

Answer 16

Fast colder air mass that moves into slow warmer air mass

causes rapid temperature changes

can cause thunderstorms as the warm air rises over the cold air

Question 17

Describe a warm air front

Answer 17

Fast warm air mass that rises over slow cooler air,

causing clouds and light to moderate precipitation, such as rain, sleet, snow, or drizzle and gradual temperature changes

Question 18

Describe a stationary air front

Answer 18

The boundary between two air masses that are not moving (cold and warm), can stay in place for days

Can be days of clouds or rain

Question 19

Describe an occluded air front

Answer 19

Formed when a warm air mass is caught between 2 cooler air masses

Weather gets cooler
can bring rain or snow

Question 20

What is a greenhouse gas?

Answer 20

Greenhouse gases are carbon dioxide, methane, and water vapor)

They make up only 1% of the atmosphere

They absorb heat (keep earth warm)

Question 21

How does the greenhouse effect work to keep Earth’s climate stable?

Answer 21

The greenhouse effect works by trapping heat from the sun in Earth’s atmosphere through certain gases, known as greenhouse gases, which absorb infrared radiation emitted by the planet, preventing it from escaping back into space and thus maintaining a relatively stable temperature on Earth, allowing life to exist as we know it; essentially acting like a blanket around the planet.

Question 22

Describe Earth’s energy budget

Answer 22

Balance of energy from the Sun absorbed and radiated by Earth. The balance between the amount of solar energy coming into Earth from the sun and the amount of energy that Earth radiates back out into space, essentially describing how much energy enters and leaves the planet at any given time, maintaining a stable temperature if balanced; if more energy comes in than leaves, the Earth warms, and vice versa.