The Earths WeatherThe Earths Weather

Layers of the AtmosphereLayers of the 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.

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

Layers of the AtmosphereLayers of the Atmosphere

Troposphere - This is the first layer above the surface and contains half of the Earth's atmosphere. Weather occurs in this layer

Stratosphere - Many jet aircrafts fly in this layer because it is very stable. Also, the ozone layer absorbs harmful rays from the sun.

Mesosphere - Meteors or rock fragments burn up in this portion of the atmosphere

Thermosphere - This is the layer with auroras. It is also where the space shuttle orbits.

Exosphere - This is the area where the atmosphere merges into space, this area is extremely thin. It is the upper limit of our atmosphere.

Troposphere - This is the first layer above the surface and contains half of the Earth's atmosphere. Weather occurs in this layer

Stratosphere - Many jet aircrafts fly in this layer because it is very stable. Also, the ozone layer absorbs harmful rays from the sun.

Mesosphere - Meteors or rock fragments burn up in this portion of the atmosphere

Thermosphere - This is the layer with auroras. It is also where the space shuttle orbits.

Exosphere - This is the area where the atmosphere merges into space, this area is extremely thin. It is the upper limit of our atmosphere.

Explanations of WeatherExplanations of Weather

Scientific explanations of weather phenomena primarily involve principles of: – heat transfer

Convection Conduction Radiation

– energy transformations production of thunder and lightning

– changes or state within the water cycle Precipitation Evaporation Condensation

Scientific explanations of weather phenomena primarily involve principles of: – heat transfer

Convection Conduction Radiation

– energy transformations production of thunder and lightning

– changes or state within the water cycle Precipitation Evaporation Condensation

WeatherWeather

As a result of these principles interacting, hot, cold, warm, and cool air masses develop.

They are usually very large and can cover several states in the United States.

These air masses develop as the air lingers in the same places for several days or weeks.

The air masses become dry or humid matching the surface below.

There are four air masses that affect the weather of the United States.

As a result of these principles interacting, hot, cold, warm, and cool air masses develop.

They are usually very large and can cover several states in the United States.

These air masses develop as the air lingers in the same places for several days or weeks.

The air masses become dry or humid matching the surface below.

There are four air masses that affect the weather of the United States.

Air massesAir masses 1) Continental polar air mass

– over Northern Canada and Alaska

2) Maritime polar air mass – over North Pacific Ocean

3) Maritime tropical air mass – over the Gulf of Mexico and Caribbean

4) Continental air mass – over the southwestern states and Mexico

1) Continental polar air mass – over Northern Canada and Alaska

2) Maritime polar air mass – over North Pacific Ocean

3) Maritime tropical air mass – over the Gulf of Mexico and Caribbean

4) Continental air mass – over the southwestern states and Mexico

Air MassesAir Masses

Air and pressureAir and pressure Air is moving molecules of gas. These gas molecules are constantly moving and

pushing on each other and anything in their way. This pushing power is called air pressure.

Air is moving molecules of gas. These gas molecules are constantly moving and

pushing on each other and anything in their way. This pushing power is called air pressure.

Air pressureAir pressure

Air pressure can change depending on how many molecules are in a given space and how fast they are moving.

The more molecules in a given space and the faster the molecules move, the greater the air pressure.

If air molecules are heated in a confined space, the pressure increases.

If the space is decreased for the same amount of molecules, the pressure will rise.

Air pressure can change depending on how many molecules are in a given space and how fast they are moving.

The more molecules in a given space and the faster the molecules move, the greater the air pressure.

If air molecules are heated in a confined space, the pressure increases.

If the space is decreased for the same amount of molecules, the pressure will rise.

Types of pressureTypes of pressure

The uneven heating of the earth results in uneven air pressure on the earth

On a weather map – "H" marks areas that have high pressure

High pressure areas are generally correlated to clear skies

High pressure prevents water vapor from rising to form clouds

– "L" marks the low pressure areas low pressure areas produce clouds and precipitation

The uneven heating of the earth results in uneven air pressure on the earth

On a weather map – "H" marks areas that have high pressure

High pressure areas are generally correlated to clear skies

High pressure prevents water vapor from rising to form clouds

– "L" marks the low pressure areas low pressure areas produce clouds and precipitation

WindWind

Wind – Produced as air moves from high pressure to

low pressure areas The closer the high and low pressure areas are to

each other, the stronger the winds

– Winds in a high pressure area move clockwise

– Winds in a lower pressure area move counter-clockwise

Wind – Produced as air moves from high pressure to

low pressure areas The closer the high and low pressure areas are to

each other, the stronger the winds

– Winds in a high pressure area move clockwise

– Winds in a lower pressure area move counter-clockwise

Weather FrontsWeather Fronts

When air masses meet– a front develops– at fronts where cold and warm air meet, we get

violent storms bad weather

– winds bring in air to equalize the pressure when a high pressure collides with a low pressure area

When air masses meet– a front develops– at fronts where cold and warm air meet, we get

violent storms bad weather

– winds bring in air to equalize the pressure when a high pressure collides with a low pressure area

Types of frontsTypes of fronts 1) warm front

– warm air replacing cold air – the lighter warm air slips over the heavier cold

air forming a gradual slope – clouds increase and become lower (drop in

height)– steady precipitation

1) warm front – warm air replacing cold air – the lighter warm air slips over the heavier cold

air forming a gradual slope – clouds increase and become lower (drop in

height)– steady precipitation

Types of frontsTypes of fronts 2) Cold front

– cold air displaces the warm air– the heavier cold air shoves under the lighter

warm air pushes the warm air up very fast carrying

moisture with it clouds form the steep slope between these two air

masses –Leads to violent storms!

2) Cold front – cold air displaces the warm air– the heavier cold air shoves under the lighter

warm air pushes the warm air up very fast carrying

moisture with it clouds form the steep slope between these two air

masses –Leads to violent storms!

Types of frontsTypes of fronts 3) stationary front

– neither the cold or warm air is advancing– clouds form on both sides of the front

3) stationary front – neither the cold or warm air is advancing– clouds form on both sides of the front

CAUSES of LIGHTNING AND THUNDER

CAUSES of LIGHTNING AND THUNDER

Lightning heats air molecules to 54,000 degrees F– This causes the surrounding molecules to explode

outward – They come back again as static electricity

caused by the moving of water molecules in the clouds

Thunder is the sound that is made by air molecules when lightning strikes through the atmosphere– results from the rapid heating and expansion of air by

lightning – causes a "shock wave" in the air

Lightning heats air molecules to 54,000 degrees F– This causes the surrounding molecules to explode

outward – They come back again as static electricity

caused by the moving of water molecules in the clouds

Thunder is the sound that is made by air molecules when lightning strikes through the atmosphere– results from the rapid heating and expansion of air by

lightning – causes a "shock wave" in the air

Reading WeatherReading Weather

Humans can use technology to predict the weather– thermometers - temperature readings– barometers - air pressure– hygrometer - relative humidity– wind vanes - direction of wind– anemometer - speed of wind– Beaufort Wind Scale - spread of wind– rain gauge - amount of rainfall– weather satellites, weather planes, weather balloons,

and radar - are used for measuring many weather components

Humans can use technology to predict the weather– thermometers - temperature readings– barometers - air pressure– hygrometer - relative humidity– wind vanes - direction of wind– anemometer - speed of wind– Beaufort Wind Scale - spread of wind– rain gauge - amount of rainfall– weather satellites, weather planes, weather balloons,

and radar - are used for measuring many weather components