Gases in the air that are present in very small amounts are called _____________.

Earth is surrounded by an envelope of gases called the ______________.

When gasoline is burned it releases the gas _______.

Clouds form when water vapor __________ out of the air.

The term used to describe the condition of the Earth's atmosphere at a given time or place.

What do dust, smoke, salt, and chemicals all have in common?

What does fire need in order to burn?

The higher the altitude , the ___________ the pressure.

As altitude increases, the density (heaviness) of the air ___________.

Air pressure is the result of the _____________ of a column (bundle) of air that is pushing down on an area.

The level of mercury in a barometer ________ as the air pressure falls.

Air pressure at sea level is __________________________ than the air pressure on top of a mountain.

What is the instrument used to measure air pressure?

Air pressure doesn't crush you because air molecules push _______________________________.

The amount of mass in a given volume of air (how heavy the air is) is called _________________.

What layer of the atmosphere is thickest over the equator?

Water forms thin, feathery clouds of ice at the top of the ____.

The stratosphere contains the ________________________.

What layer of the atmosphere do meteoroids burn up in?

What layer of the atmosphere does Earth's weather occur?

Which layer of the atmosphere is ABOVE the stratosphere?

Which layer of the atmosphere is the hottest with temperatures reaching up to 1,800 degrees?

The movement of air that is parallel to the earth's surface.

A calm area on Earth's surface where warm air rises.

What type of wind occurs over a small area?

What weather instrument measures wind speed?

If the Earth did not rotate, global winds would follow a ______________ path.

Trade winds blow toward the ________________.

What are two qualities used to describe wind?

Wind that blows during the day from the ocean towards land is ______________.

What is the term for an increase in cooler winds?

Temperature differences between the equator and the poles produce ______________________________.

What falls in the form of rain, snow, sleet, or hail during the water cycle?

Water returns to the atmosphere as water vapor by the process of ____________.

Water vapor in the atmosphere ______________ to form clouds.

the process by which water vapor becomes liquid water

molecules of liquid water escape into the air after becoming water vapor.

a measure of the amount of water vapor in the air.

weather instrument used for measuring humidity

What two conditions are required for cloud formation?

Which type of cloud often indicates that a storm is on the way?

What is a dew point?

Clouds that are wispy & feathery

Clouds that produce thunderstorms

Clouds that form in low, flat layers

clouds that look like fluffy, rounded piles of cotton

Clouds form during what process of the water cycle?

Clouds that form very near the ground are called ______?

Rain that freezes on a cold surface

What weather instrument is used to measure the amount of rain that falls?

A Maritime air mass is over ___________.

A Maritime air mass is over ___________.

A polar air mass forms near ____________.

A tropical air mass forms closer to ___________.

A large body of air that has similar temperature, humidity, and air pressure is called ___________________.

The boundary where two air masses meet is called a _________________.

A swirling center of low air pressure is called a _______________________.

High pressure centers of dry air are called _________________________.

A tropical storm that has winds over 119 Miles per hour.

A rapidly spinning column of air that reaches down to earth's surface from a cloud.

A sudden electrical discharge that accompanies thunderstorms.

This type of technology uses cameras that take pictures of the Earth's surface, clouds, storms, and snow cover.

Red half circles along a line on a weather map show a _______________.

Blue triangles along a line on a weather map show a _____________.

A line on a weather map that has blue triangles on one side and red half circles on the other indicate what type of front?

Scientists who study and predict weather

what layer of the atmosphere has no outer limit?