Topic 6

Without energy from the sun, conditions on Earth would be different. What is the energy that is radiated from

the Sun?

The energy that is radiated from the sun is called insolation (incoming solar radiation)

What part of the electromagnetic spectrum does the maximum intensity of insolation occur?

The maximum intensity of insolation is in the range of wavelengths of visible light.

• About 48% of the total energy received in the outermost parts of the atmosphere is infrared.

How is insolation transferred?

• Insolation is transferred by being absorbed, reflected and/or scatter before reaching Earth’s surface.

• Most insolation is absorbed by the Earth’s atmosphere. (due to ozone – o3)

• Ozone holes are areas where the ozone has been greatly reduced

• South pole

• Other gases also can absorb long wave infrared radiation. These are water vapor, carbon dioxide (CO2 and methane (CH4).

What is the most common form insolation is transferred?

The most common form of insolation absorbed by the atmosphere is short wave radiation.

What are the factors that affect absorption?

• Factors that affect absorption of insolation at the Earth’s surface are– The amount of cloud cover. More clouds =

more reflection or scattering – Angle of incidence (the angle at which

insolation strikes the surface) – The higher the angle of incidence = the more insolation will be absorbed

– Surface characteristics – texture, color, land vs. water

What is transpiration and how is it effected by insolation?

• Transpiration is the process in which plants release water vapor into the atmosphere.

• Insolation fuels and increases transpiration• More insolation = more transpiration

What is the greenhouse effect? • The greenhouse effect is when energy (insolation) is

transferred through the Earth’s atmosphere.

• Objects absorb the short wave radiation and are heated.

• These heated objects, then give off (reradiated) long wave infrared radiation.

• The Earth absorbs the

short wave radiation from the

Sun and reradiates long wave

radiation (infrared)

• Greenhouse effect has been

linked with Global warming