Chapter 7 The Atmosphere Key Concepts

How does increasing altitude affect air pressure and density?

Air pressure decreases as altitude increases. As air pressure decreases, so does the density.

How is temperature measured?

Air temperature is usually measured with a thermometer.

What are some of the properties of air?

Because air has mass, it also has other properties, including density and pressure.

What is the composition of Earth's atmosphere?

Earth's atmosphere is made up of nitrogen, oxygen, carbon dioxide, water vapor, and many other gases, as well as particles of liquids and solids.

How is the atmosphere important to living things?

Earth's atmosphere makes conditions on Earth suitable for living things.

In what three ways is heat transferred?

Heat is transferred in three ways within the atmosphere: radiation, conduction, and convection.

How do local winds and global winds differ?

Like local winds, global winds are created by the unequal heating of Earth's surface. But unlike local winds, global winds occur over a large area.

What causes winds?

Local winds area caused by the unequal hating of Earth's surface within a small area.

In what from does energy from the sun travel to Earth?

Most of the energy from the sun travels to Earth in the form of visible light.

What are the four main layers of the atmosphere?

Scientists divide Earth's atmosphere into four main layers classified according to changes in temperature. These layers are the troposphere, the stratosphere, the mesosphere, and the thermosphere.

What happens to the sun's energy when it reaches Earth?

Some sunlight is absorbed or reflected by the atmosphere before it can reach the surface. The rest passes through the atmosphere to the surface. When Earth's surface is heated, it radiates most of the energy back into the atmosphere as infrared radiation.

What causes smog and acid rain?

The burning of fossil fuels can cause smog and acid rain.

Where are the major global wind belts located?

The major global wind belts are the trade winds, the polar easterlies, and the prevailing westerlies.

What are the characteristics of each layer?

The troposphere is the layer of the atmosphere in which Earth's weather occurs. The stratosphere is the second layer of the atmosphere and contains the ozone layer. The mesosphere is the layer of the atmosphere that protects Earth's surface from bring hit by most meteoroids. The outmost layer of Earth's atmosphere is the thermosphere.

What instruments are used to measure air pressure?

Two kinds of barometers are mercury barometers and aneroid barometers.

How is heat transferred in the troposphere?

Within the troposphere, heat is transferred mostly by convection.