Lecture 05

Question 1

According to the energy law; the energy received and emitted should be 255 K, but it is 288 K

Answer 1

Missing Kelvins because of the atmosphere

Question 2

The Earth’s energy received and emitted without its atmosphere

Answer 2

255 K (-18 Celsius)

Question 3

The Earth’s energy received and emitted with its atmosphere

Answer 3

288 K (-15 Celsius)

Question 4

Why is the Earth’s energy colder than it should be?

Answer 4

Because of the greenhouse effect: Greenhouse gases (H₂O vapor, CO₂, CH₄, etc.) and clouds absorb some of the infrared radiation the surface emits and re-radiate part of it back downward.
This slows the loss of heat to space, so the surface must warm until outgoing infrared at the top of the atmosphere balances incoming solar energy.

Question 5

Not a single uniform structure; thin layer of gas (N2 O2 CO2) preventing all solar energy from directly hitting the surface of the planet

Answer 5

The atmosphere

Question 6

What’s the first layer of the atmosphere (where weather takes place)

Answer 6

The troposphere

Question 7

What’s the second layer of the atmosphere?

Answer 7

Stratosphere

Question 8

What’s the third layer of the atmosphere?

Answer 8

Mesosphere

Question 9

How many layers in total does the atmosphere have?

Answer 9

4 layers

Question 10

Of what is the atmosphere composed of ?

Answer 10

Numerous gases (N2, O2, CO2)-Clouds-Dust-Microplastic, it has a lot of physical particles to interfere with wavelengths of energy moving from the sun to the surface of the planet

Question 11

Processes which interact with heat transfer in the atmosphere help to create

Answer 11

Global energy balance

Question 12

The solar light entering the atmosphere collide with air, dust and cloud particles, this deflects light in all directions (short wavelength is the most effective for this process–> that’s why the sky is blue)

Answer 12

Scattering

Question 13

When is there more scattering and longer wavelengths of light that scatters as well (longest wavelengths appear red)

Answer 13

At the end or the beginning of the day during sunset or sunrise

Question 14

How much solar radiation is impacted by scattering as shortwave radiation

Answer 14

23%

Question 15

Solar light entering the atmosphere collide with clouds and the terrestrial surface, it goes back to the source to where the energy source came from, it doesn’t move in all direction

Answer 15

Reflection

Question 16

Related to reflection, it is the reflectance of a surface and how much of a given energy source will be reflected back (instead of absorbed)

Answer 16

Albedo

Question 17

The more visible light is absorbed (low albedo) when…

Answer 17

The object is darker

Question 18

The more visible light is reflected (high albedo) when…

Answer 18

The object is lighter

Question 19

Which of these two has a higher albedo : snow or water ?

Answer 19

Snow

Question 20

How much energy is directly reflected by surface albedo?

Answer 20

8%

Question 21

Knowing that energy is sent back into space how much in percentage is sent back combining albedo and scattering?

Answer 21

31%

Question 22

Process where kinetic energy in the form of electromagnetic radiation is soaked up by colder substances in the atmosphere and the terrestrial surface

Answer 22

Absorption

Question 23

What is energy absorbed by?

Answer 23

Clouds, terrestrial surface and atmosphere

Question 24

What’s in percentage, the total energy absorbed by terrestrial surfaces?

Answer 24

49%

Question 25

What's the total energy solar absorbed by atmospheric reservoirs?

Answer 25

20%

Question 26

Can energy be created or destroyed?

Answer 26

No it is only transformed

Question 27

The energetic shortwave radiation released by the sun is absorbed by cooler objects on Earth, it depends on the object temperature

Answer 27

Emission

Question 28

Objects that are better at absorbing some wavelengths over others

Answer 28

Selective absorbers

Question 29

Longwave absorbing gases trap some of the heat that the planet would emit back into space, these gases are...

Answer 29

Greenhouse gases

Question 30

Re-releasing energy into space or back to the planet's surface for multiple times as long as the cycle can continue, it is the recycling of energy through re-emission, GHGs are helpful in that case

Answer 30

Re-emission

Question 31

What are low clouds practical for?

Answer 31

They are useful for planetary cooling by reflecting high levels of incoming shortwave radiation, they re-emit more infrared energy back into space

Question 32

What are high clouds practical for?

Answer 32

They tend to be thin, they are useful for planetary warming, it allows shortwave radiation to be absorbed at the planet surface

Question 33

The energy that moves directly from the molecules of the ground to molecules in the air directly touching the ground, it is the transfer of energy between two substances which are in direct contact

Answer 33

Conduction

Question 34

Energy that moves through warming air in the atmosphere, the air is warmed through conduction from terrestrial surfaces (the lighter air rises)

Answer 34

Convection

Question 35

The energy taken in and released by water as it transitions through different states of matter, this energy is taken with water to water vapor, it releases energy through "the magic of evaporation"

Answer 35

Latent heat transfer

Question 36

Why is the solar energy distributed over a greater area at the bottom of the planet and more concentrated at the equator?

Answer 36

Because of its spheric shape; the energy then depends on where we are positioned on the planet