Mechanism Of The Greenhouse Effect

Question 1

Equation for wavelength at which max emissions occur by radiating?

Answer 1

Wavelength peak= 2.897/T

Question 2

What is the max wavelength for VISIBLE LIGHT that the earth receives?

Answer 2

0.75-0.4 micrometers

Question 3

What is the term for the amount of light reflected back into outer space?

Answer 3

Albedo
High= Snow and clouds
Low= Soils

Question 4

What form is the emitted energy (not light)

Answer 4

Thermal Infrared

5-100 micrometers

Question 5

Does a warmer body emit more or less energy? What is an example

Answer 5

More energy

Ex: black body

Question 6

Gases that absorb thermal IR can do 2 things with it

Answer 6

1. Re-emit it back to the earth

2. Lost as heat to space

Question 7

What is the Greenhouse effect?

Answer 7

Outgoing IR by atmospheric constituents and its dissipation as heat to increase the temperature of the atmosphere (natural mechanism)

Question 8

What is the Enhanced Greenhouse effect?

Answer 8

An increase in the number of molecules that absorb IR and re-emit it

Question 9

What atmospheric gases absorb and don’t absorb IR light?

Answer 9

Don’t: N2, O2 and Ar

Do: H2O vapour and CO2

Question 10

Why is little amounts of IR emitted near the surface escapes into space?

Answer 10

Because IR realsed from closer to the surface will be absorbed by the air closest to the ground and will then be re-emitted. Therefore: not a lot of IR escapes to space because it is re-emitted into the surrounding areas

Question 11

As altitude increases, what happens to the IR absorption ?

Answer 11

Less IR is absorbed

Question 12

What are 2 ways that and increase in the concentration of CO2 can cause cooling in the stratosphere?

Answer 12

1. Because more thermal IR is absorbed at low altitudes

2. CO2 emits more thermal IR up into space

Question 13

How is the earth kept warm?

Answer 13

Sun radiation as light