The Atmosphere

Module 3

Part 1

Molecules

Everything in the world is made up of atoms and molecues These molecules move differently depending on their state of

matter – solid, liquid, or gas

Density

The density of solids does not change shape. Solids will keep their shape even when moved.

Liquids

The density of liquids changes slightly Liquids will change shape, but are still bound together If you spill a glass of water, the water changes its shape to a

puddle, but the water stays together

Gasses

The molecules in glasses are not bound at all They are free to move about and will only stop when they are

confined to a container or by gravity

Wind

Gases in the air move around trying to equalize the pressure

When a low pressure area is next to a high pressure area, the gases will move from the high to low pressure areas to try to equalize the pressure

The moving about of this pressure is wind

Remember winds blow from HIGH to LOW

Water

Water, unlike air and land, does not change temperature quickly

It can absorb a lot of heat energy before the temperature of the water changes

The same is true in reverse – Water must loose a lot of heat energy before it cools noticeably

Sea Breezes

During the day the sun heats the land quickly As the land heats, the air above the land is heated The hot air rises becoming less dense creating a low

pressure The air over the sea is cooler because it takes much

longer to heat the water The air over the sea keeps its high pressure

Sea Breezes

The difference in pressure creates wind or a breeze

Wind blows from the sea to the land to try to equalize the pressure – this is called sea breeze

Which One?

Land Breeze

At night the land cools rapidly Because the air of the sea is warmer, the

wind direction changes The cooler heavier air over the land forms a

high pressure causing the air to move towards the sea where the air pressure is lower

This is called a land breeze

Currents

Ocean currents are like large rivers that run within the ocean

Without this motion the equator regions would be much warmer and the polar regions would be much colder

Both the atmosphere and the ocean are in constant motion

Currents

Barometer

What is a barometer? An instrument used to

measure atmospheric pressure

Uses mercury as its liquid – not water

Atmosphere

Homosphere: The lower layer of earth’s atmosphere, which exists from ground level to roughly 80 kilometers (50 miles) above sea level

Heterosphere: The upper layer of earth’s atmosphere, which exists high than roughly 80 kilomters (50 miles) above sea level

Layers of the Earth’s Atmosphere

The atmosphere is divided into five layers. It is thickest near the surface and thins out with height until it eventually merges with space.

1) The troposphere is the first layer above the surface and contains half of the Earth's atmosphere. Weather occurs in this layer.

2) Many jet aircrafts fly in the stratosphere because it is very stable. Also, the ozone layer absorbs harmful rays from the Sun.

Layers of the Earth’s Atmosphere

3) Meteors or rock fragments burn up in the mesosphere.

4) The thermosphere is a layer with auroras. It is also where the space shuttle orbits.

5) The atmosphere merges into space in the extremely thin exosphere. This is the upper limit of our atmosphere.

Atmosphere

Mount McKinley

Facts

Location: Mount Mckinley is located in south central Alaska; in the Alaska range.

Absolute Location: It is located 63 degrees north, and 151 degrees West.

Famous for: It is the highest peak in North America. It is 6,194 m. (20,230ft.) above sea level.

Facts

Description: The Native American knew Mount McKiley as "Denli" meaning the high one. Some convient centers near Mount McKinley are Talkeenta, Alaska. The nearest major airport is in Anchorage, Alaska.

Three Interesting Facts: 1. Mount McKinley was named after President William McKinley in 1896.

2. An Anglo-American clergyman, Hudson Stuck first reached the summit in1913.

3. Some of the very best months to climb Mount McKinley are: April, May, and June.

Mt.McKinley – from Anchorage, Alaska – 200 miles away!