Solar Radiation and the Atmosphere

Question 1

What is the Sun made of?

Answer 1

Dense hydrogen gas

Question 2

What are the reactants and products of nuclear fusion?

Answer 2

hydrogen + hydrogen —> helium + energy

Question 3

How much of the solar system’s matter is present in the Sun?

Answer 3

99.8%

Question 4

What two things enable nuclear fusion to occur in the Sun?

Answer 4

heat and pressure

Question 5

Protons, neutrons and electrons in most common isotope of hydrogen

Answer 5

protons = 1
neutrons = 0
electrons = 1

Question 6

What are the two other isotopes of hydrogen called?

Answer 6

deuterium
tritium

Question 7

Define insolation

Answer 7

the amount of solar radiation reaching a given area

Question 8

Define albedo

Answer 8

a measure of how reflective a surface is

Question 9

What is energy?

Answer 9

the ability to do work

Question 10

Where does most of the energy on Earth come from?

Answer 10

the Sun

Question 11

The majority of Solar radiation is in what wavelength?

Answer 11

infra-red

Question 12

Where on Earth do the Sun’s rays hit most directly?

Answer 12

the equator

Question 13

Where on Earth do the Sun’s rays hit least directly?

Answer 13

the poles

Question 14

Wavelength of UV

Answer 14

100-350 nm

shorter

Question 15

Environmental Importance of UV

Answer 15

important for the production of vitamin D

inhibits photosynthesis in plants and algae (phytoplankton = 1/2 O2 in atmosphere)

dissolves dead organic matter - useful for cleaning water

kills bacteria

Question 16

Wavelength of Visible Light

Answer 16

380-700 nm

Question 17

Environmental importance of Visible Light

Answer 17

photosynthesis in plants

regulates animal behaviour

degrades organic pollutants

enables us to see

Question 18

Wavelength of Infra-red

Answer 18

700-1000 nm

longer

Question 19

Environmental importance of Infra-red

Answer 19

keeps a stable temperature and climate

causes climate change

affects range of tolerance

Question 20

What is conduction?

Answer 20

when heat moves from areas of more heat to areas of less heat by DIRECT CONTACT

Question 21

What is convection?

Answer 21

where heat is transferred by movement of heated materials

cooling and rising effect

Question 22

What is a convection cell?

Answer 22

rising of warm air and sinking of cool air

Question 23

How much of the Sun’s energy is filtered out by the atmosphere?

Answer 23

50%

Question 24

What happens to most of the energy that reaches the surface?

Answer 24

absorbed

warms soil/water/rock

Question 25

What happens to the rest of the energy that reaches the surface?

Answer 25

re-radiated back into the air as heat (3%)

Question 26

What is the Earth’s energy budget?

Answer 26

the difference between the energy entering and exiting the atmosphere

usually in balance

Question 27

What happens when the Earth absorbs more energy than it emits?

Answer 27

warms up

Question 28

What happens when the Earth emits more energy than it absorbs?

Answer 28

cools down

Question 29

What is the greenhouse effect?

Answer 29

the warming of the atmosphere due to insulation by greenhouse gases

Question 30

How is the greenhouse effect helpful for life on Earth?

Answer 30

maintains a stable temperature - within our range of tolerance

important for photosynthesis

Question 31

What human activities are enhancing the greenhouse effect?

Answer 31

burning fossil fuels and deforestation - release CO2

grazing livestock, rice fields, landfill sites (anaerobic breakdown of organic material) - release methane

fertilisers and vehicles - release nitrous oxides

Question 32

How do human activities enhance the greenhouse effect?

Answer 32

increase levels of C02 (by 50% since 1750), methane and nitrous oxides cause global warming