1. Solar Radiation

Solar Radiation

By Jason King

SUMMER SCHOOL

RADIATION

is one way to transfer heat.

​

To “radiate” means to send out or spread from a central location. Whether it is light, sound, waves, rays, flower petals or pain, if something radiates then it spreads outward from a starting point.​

RADIATION

Every object around you is continually radiating, unless its temperature is at absolute zero (−273.15 °C), at which point its molecules completely stop moving.​

​

Have you ever experienced radiation

personally???

RADIATION

With radiation, electromagnetic waves carry the energy.

Electromagnetic radiation comes from accelerating electric charges. On a molecular level, that’s what happens as objects warm up — their molecules vibrate harder and harder, causing acceleration of electric charges.

SOLAR RADIATION

Solar radiation is light

also known as electromagnetic radiation

that is emitted by the sun

​

CLASSICAL ELECTROMAGNETISM

This theory depicts light as a transverse wave composed of oscillating ELECTRIC and MAGNETIC fields which are at right angels to each

other and perpendicular to the direction that the wave moves.

ELECTROMAGNETIC WAVES

CHARACHTERISTICS:

• AMPLITUDE

• ​WAVELENGHT

• FREQUENCY ​

​Different frequencies of EMWaves produce different kinds of light.

SOLAR RADIATION SPECTRUM

The part of the electromagnetic spectrum that reaches Earth from the sun is between 100nm(UV) and 1mm(IR).​

This band is broken into three ranges: ultraviolet, visible, and infrared radiation.​

SOLAR RADIATION SPECTRUM

• Ultraviolet contains wavelengths between 100-400 nm

• Visible light falls within the range of 400-700 nm

• Infrared light contains wavelengths from 700 nm to over 1 mm​

• ​

SOLAR RADIATION SPECTRUM

​In the visible light spectrum, the colors are determined by the length. Longer wavelengths appear red while shorter wavelengths are blue/violet as they range closer to the ultraviolet spectrum

SOLAR RADIATION MEASURED

Solar radiation is measured in wavelengths or frequency. As light travels in a wave, a wavelength is defined as the distance from peak to peak and is measured in nanometers (nm).

SOLAR RADIATION MEASURED

Frequency is defined as wavelength cycles per second and is expressed in hertz (Hz).

Bands with shorter wavelengths produce higher frequencies. Likewise, the longer the wavelength, the longer it will take to complete a cycle, which produces a lower frequency

SOLAR ENERGY

The energy of the wavelength increases with the frequency and decreases with the size of the wavelength.

In other words, shorter wavelengths are more energetic than longer ones. This means that ultraviolet radiation is more energetic than infrared radiation.

Due to this extra energy, shorter wavelengths tend to cause more harm than longer wavelengths.

The more energy a wavelength has, the easier it is to disrupt the molecule that absorbs it. Ultraviolet light can cause damage to DNA and other important cellular structures​

SOLAR RADIATION

The Sun is a huge thermal reactor about 147 million km away.

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There are differences in climate around the world because of differing amounts of radiation received from the Sun at different parts of the Earth at different times of the year.​

CLIMATE ZONES

The most important latitudes:

• ​EQUATOR

• TROPIC OF CANCER

• ​TROPIC OF CAPRICORN

• THE ARCTIC ​CIRCLE

• ​ANTARCTIC CIRLCE

CLIMATE ZONES

The Climate Zones:

• ​TORRID/TROPIC ZONE

• TEMPERATE ZONE

• ​FRIGID ZONES

  ​

More heat from the Sun is received

near the equator than near the north

and south poles where the angle of the

Sun's rays is lower. This is why tropical

climates differ so much from polar climates.​

SOLAR RADIATION

The amount of solar radiation that reaches any one spot on the Earth's surface varies according to:

• Geographic location

• Time of the day

• Season

• Local landscape

• Local weather

SOLAR RADIATION

As sunlight passes through the atmosphere, some of it is absorbed, scattered, and reflected by:

• Air molecules

• Water vapor

• Clouds

• Dust

• Pollutants

• Forest fires

• Volcanoes

  This is called diffuse solar radiation.

GLOBAL SOLAR RADIATION

The solar radiation that reaches the Earth's surface without being diffused is called direct beam solar radiation.

The sum of the diffuse and direct solar radiation is called global solar radiation. Atmospheric conditions can reduce direct beam radiation by 10% on clear, dry days and by 100% during thick, cloudy days.​

Multiple Choice

In order of most to least penetrating radiation we have

• Alpha , Beta,  Gamma
• Beta , Gamma , Alpha
• Gamma, Beta, Alpha
• Gamma, Alpha, Beta

Multiple Choice

What unit is radiation dose measured in?

• Sieverts (Sv)

• Seaverts (sV)

• Radons (Rn)

• Becquerels (Bq)

Multiple Choice

Which theory depicts light as a transverse wave composed of oscillating ELECTRIC and MAGNETIC fields which are at right angels to each

other and perpendicular to the direction that the wave moves.

• Classical Mechanics

• Thermodynamics

• Classical Electromagnetism

• Relativistic Mechanics

Multiple Choice

Light consists of oscillating _____ and _____ fields.

• Magnetic

  Gravitational

• Gravitational

  Electric

• Electric

  Magnetic

• Electrons

  Protons

Multiple Choice

In the 19th century sophisticated description of the light, which we call classical electromagnetism, was developed by ...

• Issac Newton

• James Clerk Maxwell

• Christiaan Huygens

• Albert Einstein

Multiple Choice

Electromagnetic waves vary in

• the speed they travel in a vacuum

• wavelength and frequency

• the way they reflect

• the orientation of their electric and magnetic fields

Multiple Choice

The visible light spectrum ranges between

• radio waves and X-rays

• infrared rays and ultraviolet rays

• television waves and infrared rays

• ultraviolet rays and gamma rays

Multiple Choice

As light travels in a wave, a _______ is defined as the distance from peak to pea

• Amplitude

• Wavelength

• Frequency

• Trough

• Crest

Multiple Select

Which TWO type of electromagnetic waves have a low frequency and a long wavelength?

• Gamma rays

• Infrared

• Microwaves

• Radio waves

Multiple Choice

At which speed do all electromagnetic waves move?

• Speed of Sound

• 3 times the speed of sound

• 5 times speed of light

• Speed of Light

Multiple Choice

The energy of the wavelength decreases with the frequency and increases with the size of the wavelength.

• True

• False

Multiple Choice

Which has a longer wavelength?

• infrared

• ultraviolet

Multiple Choice

Light in vacuum always moves at roughly _____KM/S

• 300 000

• 300 000 000

• 3 000

• 343

Multiple Choice

This is the first part of the spectrum that animals can detected.

• Infrared

• Ultraviolet

• Gamma ray

• X ray

Multiple Choice

Which type of electromagnetic energy carries the least energy?

• X-Rays

• Visible Light

• Ultraviolet

• Microwaves

Multiple Choice

The longer wavelength produces a lower frequency

• True

• False

Multiple Choice

_____ can cause damage to DNA and other important cellular structures

• Infrared

• Radiowaves

• Ultraviolet

• Microwaves

Multiple Choice

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There are no differences in climate around the world because of radiation received from the Sun at different parts of the Earth at different times of the year is equal.

• True

• False

Multiple Choice

The climate zones of earth, are distinguished by the ______ that run across the Earth's surface.

• Timezones

• latitudes

• Longitudes

• Microwaves

Multiple Choice

Summer Solstice usually take place on ____

• 23 of Sept

• 22 of December

• 21 of March

• 22 of June

Multiple Select

Equinox usually take place on ____

• 23 of September

• 22 of December

• 21 of March

• 22 of June

Multiple Choice

Thailand is located in _____ climate zone

• Frigit

• Tropical

• Temperate