Temperature and Temperature and the Atmospherethe Atmosphere

Without heat there is no Without heat there is no weather.weather.

The most influential factor effecting The most influential factor effecting weatherweather in the atmosphere is in the atmosphere is heatheat. .

Solar HeatingSolar Heating Most of heat found in our atmosphere comes from the Sun. Most of heat found in our atmosphere comes from the Sun. The Sun produces a massive amount of energy, every The Sun produces a massive amount of energy, every

moment of every day. moment of every day. Most of the energy is radiated outward into the furthest Most of the energy is radiated outward into the furthest

reaches of the Solar System. reaches of the Solar System.

Electromagnetic Electromagnetic SpectrumSpectrum

The heat produced by the The heat produced by the Sun travels from the Sun to Sun travels from the Sun to the Earth via waves known the Earth via waves known as as electromagnetic waveselectromagnetic waves. .

All these waves together are All these waves together are known as the known as the electromagnetic electromagnetic spectrumspectrum. .

Broken into three separate Broken into three separate categories categories Ultra violet waves - the shortest Ultra violet waves - the shortest Visible light - the medium sized Visible light - the medium sized

waves waves Infrared - the longest waves Infrared - the longest waves

Microwaves and radio wavesMicrowaves and radio waves

Ultraviolet WavesUltraviolet Waves Waves measuring under 0.4 micrometers Waves measuring under 0.4 micrometers These short waves are extremely These short waves are extremely

dangerous to living organisms. dangerous to living organisms. Long term exposure to ultraviolet radiation Long term exposure to ultraviolet radiation

would seriously hurt and even kill most life would seriously hurt and even kill most life forms on Earth, including humans. forms on Earth, including humans.

Most of these waves never reach the surface Most of these waves never reach the surface of the Earth. of the Earth.

They are either absorbed, or reflected and They are either absorbed, or reflected and bounced away by molecules in the upper bounced away by molecules in the upper atmosphere. atmosphere.

Visible Light WavesVisible Light Waves Waves with a length of between 0.4 Waves with a length of between 0.4

and 0.7 micrometers and 0.7 micrometers Can be detected by the human eye. Can be detected by the human eye. Shorter visible light wavelengths, are Shorter visible light wavelengths, are

bluer in color, while longer visible bluer in color, while longer visible light wavelengths are redder in color. light wavelengths are redder in color.

The wavelengths detectible by the The wavelengths detectible by the human eye represent only about 3% of human eye represent only about 3% of the total electromagnetic spectrum.the total electromagnetic spectrum.

Infrared WavesInfrared Waves

Infrared waves are commonly Infrared waves are commonly referred to has heat rays. referred to has heat rays.

Heat is in infrared Heat is in infrared radiationradiation. .

Transferring Heat Transferring Heat

There are three natural processes There are three natural processes that can be used to transfer heat. that can be used to transfer heat. RadiationRadiation conductionconduction ConvectionConvection

RadiationRadiation All objects radiate energy and All objects radiate energy and

heat.heat. Radiation leaves an object in the Radiation leaves an object in the

form of waves. form of waves. The hotter an object, the shorter The hotter an object, the shorter

the wavelength of this radiation. the wavelength of this radiation. The infrared waves, or heat rays The infrared waves, or heat rays

leave the hot fire, and radiate out leave the hot fire, and radiate out towards your hands. towards your hands.

ConductionConduction As one molecule is heated it As one molecule is heated it

begins to move and shake rapidly. begins to move and shake rapidly. As it does so, it passes some of its As it does so, it passes some of its

heat energy to other molecules heat energy to other molecules around it.around it. All the molecules of an object pass All the molecules of an object pass

heat from one to another, until heat from one to another, until they are all hot. they are all hot.

As the hotdog cooks, the fire As the hotdog cooks, the fire heats the end of the hanger. heats the end of the hanger. Eventually the end we are holding Eventually the end we are holding

will become too hot for us to will become too hot for us to handle. handle.

Heat was transferred from the Heat was transferred from the flames to the metal, and than from flames to the metal, and than from molecule to molecule in the molecule to molecule in the hanger via conduction until it hanger via conduction until it reached your sensitive fingers reached your sensitive fingers

ConvectionConvection Convection takes place when heated Convection takes place when heated

molecules move from one place to another, molecules move from one place to another, taking the heat with them.taking the heat with them. Common in both the atmosphere, as well as in the Common in both the atmosphere, as well as in the

oceans. oceans. Heated air in our atmosphere expands, Heated air in our atmosphere expands,

becoming less dense and rises upward. Cooler becoming less dense and rises upward. Cooler air rushes in to replace the air that lifted up. air rushes in to replace the air that lifted up.

As warm air rises, and cool are falls, a giant As warm air rises, and cool are falls, a giant circular pattern is created. circular pattern is created.

Eventually the warmer air cools, and begins Eventually the warmer air cools, and begins to fall again. to fall again.

Objects React To Heat Objects React To Heat

What happens to that heat once it What happens to that heat once it arrives at a destination depends on a arrives at a destination depends on a number of factors. number of factors. Size of objectSize of object Current temperature of objectCurrent temperature of object Material object made ofMaterial object made of

As heat reaches its destination it will As heat reaches its destination it will either be either be absorbed, reflected, absorbed, reflected, scattered, or transmittedscattered, or transmitted

Heat Absorption Heat Absorption

Heat enters an object, warming it. Heat enters an object, warming it. The longer the object is exposed to the The longer the object is exposed to the

heat source, the more heat that it absorbs.heat source, the more heat that it absorbs. Different objects absorb heat at Different objects absorb heat at

different rates. Some objects are different rates. Some objects are excellent absorbers, while others are excellent absorbers, while others are very poor absorbers. very poor absorbers. Dark colored objects absorb well Dark colored objects absorb well

Absorb more lightAbsorb more light Light colors do not absorb heat wellLight colors do not absorb heat well

Heat Reflection Heat Reflection

The opposite of absorption The opposite of absorption Heat energy is bounced, or reflected Heat energy is bounced, or reflected

off in the opposite direction. off in the opposite direction. Objects which are good at Objects which are good at

absorption are as a result poor absorption are as a result poor reflectors, and vice versa. reflectors, and vice versa.

Scattering Scattering The waves of light, heat, and The waves of light, heat, and

ultraviolet radiation interact ultraviolet radiation interact with the particulates found with the particulates found in the atmosphere and water in the atmosphere and water Dust, gases, water and Dust, gases, water and

pollutionpollution Electromagnetic waves hit Electromagnetic waves hit

these particulates they are these particulates they are bounced off in random bounced off in random directions.directions. Direction depends on size and Direction depends on size and

shape of particles.shape of particles. Smaller wavelengths, such as Smaller wavelengths, such as

blue light tend to scatter more blue light tend to scatter more than longer wavelengths. than longer wavelengths.

This is why the sky looks blue This is why the sky looks blue

Heat Transmission Heat Transmission

Occurs when electromagnetic Occurs when electromagnetic energy is allowed to pass completely energy is allowed to pass completely through an objectthrough an object glass window, or through water in a glass window, or through water in a

lake or stream.lake or stream.

Adiabatic Temperature Adiabatic Temperature Changes Changes

Heated air expands becoming less Heated air expands becoming less dense and lighterdense and lighter Rises upwards and continues to expand Rises upwards and continues to expand

because of decreasing air pressurebecause of decreasing air pressure Spreading out of molecules requires Spreading out of molecules requires

energy and air lose energy and energy and air lose energy and temperature dropstemperature drops

Cooler air begins to fall and becomes Cooler air begins to fall and becomes compressed causing it to heat up and compressed causing it to heat up and temperature risestemperature rises

Latent Heat Latent Heat Water allows the Water allows the

atmosphere to store heatatmosphere to store heat Stored heat is latent heatStored heat is latent heat Water evaporates off Water evaporates off

Earth’s surface and rises Earth’s surface and rises into air carrying heat into into air carrying heat into the atmospherethe atmosphere

Water condenses and falls Water condenses and falls to ground as precipitation to ground as precipitation and heat returns to groundand heat returns to ground

The Heat Budget The Heat Budget

Heat coming into the atmosphere is Heat coming into the atmosphere is generally balanced with the heat generally balanced with the heat leaving the atmosphereleaving the atmosphere This keeps the planet’s temperature This keeps the planet’s temperature

stablestable It may vary from day to day and place It may vary from day to day and place

to place but overall it relatively stableto place but overall it relatively stable

Heat And Weather Heat And Weather Unequal heating of the Unequal heating of the

surface of the Earth is surface of the Earth is the principal cause of the principal cause of weather weather

As the gases in Earth’s As the gases in Earth’s atmosphere heat up, atmosphere heat up, they begin to expand, they begin to expand, or spread out. Air or spread out. Air begins to rush outward begins to rush outward towards places where towards places where there is less pressure. there is less pressure. This rushing air is what This rushing air is what

causes wind.causes wind.

Latitude Affects Latitude Affects Temperature Temperature

Latitude – the distance from the Latitude – the distance from the Earth’s equator contributes to Earth’s equator contributes to unequal heating of the Earth’s unequal heating of the Earth’s surface.surface. The farther from the equator a location The farther from the equator a location

is the less sunlight it receives and thus is the less sunlight it receives and thus less heat.less heat.

Day Length Affects Day Length Affects Temperature Temperature

The longer that a day lasts, the more time that The longer that a day lasts, the more time that there is for Earth to absorb energy from the there is for Earth to absorb energy from the Sun. Sun. Longer days result in warmer daysLonger days result in warmer days Shorter days result in cooler days. Shorter days result in cooler days.

On the equator the length of days changes very On the equator the length of days changes very little throughout the year. little throughout the year. Day is almost exactly 12 hours and night is 12 hours. Day is almost exactly 12 hours and night is 12 hours.

The further away that one travels from the The further away that one travels from the equator the more variation in length of day that equator the more variation in length of day that will be observed. will be observed.

Atmospheric Obstructions Atmospheric Obstructions Affect Temperature Affect Temperature

Clouds can block light and heat from Clouds can block light and heat from reaching from reaching the surface reaching from reaching the surface Causes a drop in temperatureCauses a drop in temperature

Land And Water Affect Land And Water Affect Temperature Temperature

The atmosphere of the Earth is primarily The atmosphere of the Earth is primarily heated by radiation coming off of the heated by radiation coming off of the Earth. Earth. 50% of the Sun’s energy is absorbed by the 50% of the Sun’s energy is absorbed by the

Earth, and than released back into the Earth, and than released back into the atmosphere. atmosphere.

The temperature of the air in a location can be The temperature of the air in a location can be effected by the materials found on the surface. effected by the materials found on the surface. Forest (absorb) vs. Desert (reflect)Forest (absorb) vs. Desert (reflect) Water absorbs heat slowly and releases heat slowlyWater absorbs heat slowly and releases heat slowly

Our Atmosphere Our Atmosphere Transfers Heat Transfers Heat

Earth is constantly trying to balance Earth is constantly trying to balance temperature differences. temperature differences. Cooler areas attract warm air Cooler areas attract warm air Warmer areas push air outward in an Warmer areas push air outward in an

attempt to cool itself down attempt to cool itself down Locally air rushes from one place to Locally air rushes from one place to

another, as it attempts to balance another, as it attempts to balance temperature and pressure temperature and pressure

HomeworkHomework

Chapter 3 Section 2 Assessment Chapter 3 Section 2 Assessment QuestionsQuestions

Winds WorksheetWinds Worksheet Weather WorksheetWeather Worksheet