Earth and Beyond (Assignment 4)

Question 1

Why is the atmosphere so important for life on Earth?

Answer 1

• SUPPLY us with air (O2) to breath
• PROTECT us against heat and radiation of the sun
• Limit changes in day and night TEMPERATURES
• Protect us against METEORS
• CO2 for plants to PHOTOSYNTHESIZE

Question 2

Name the different gasses in the atmosphere

Answer 2

Nitrogen - 78%
Oxygen - 21%
Carbon dioxide - 0.03%
Other - 0.97%

Question 3

Name the different layers of the ATMOSPHERE and their depth

Answer 3

Troposphere - 0 - 10 km from earth’s surface
Stratosphere - 10 - 50 km from earth’s surface
Mesosphere - 50 - 80 km from earth’s surface
Termosphere - 80 to 350 km from earth’s surface

Question 4

What do you find in the TROPOSHERE

Answer 4

This is where plants and animals live
Lots of weather changes

Question 5

What do you find in the STRATOSPHERE

Answer 5

Aeroplanes fly here
Ozone layer (15-50 km)

Question 6

What do you find in the MESOSPHERE

Answer 6

Shooting stars and meteors

Question 7

What do you find in the TERMOSPHERE

Answer 7

ISS (International Space Station) - (320-380 km)
Hubble space telescope (595km)
GPS (20 000 km)
Polar lights
Weather and TV Satellites

Question 8

What keeps the gas particles of the atmosphere from drifting off into space?

Answer 8

Gravitational forces

Question 9

What WORD describes the extent to which the particles of a gas are CROWDED closely together?

Answer 9

Density

Question 10

Why is the DENSITY of air greater at sea level than at a high altitude?

Answer 10

-At sea level: pressure of the air column squeezes
the air particles together DOWN making the air
more DENSE
-At higher level: not such a TALL column of air
pressing down and therefore the air particles are not
so tightly packed..the air is LESS dense

Question 11

Name the MAIN GASES in the air

Answer 11

1) Nitrogen
2) Oxygen

Question 12

What approximate proportions of air ae made up of these 2 gases?

Answer 12

78% nitrogen
21% oxygen

Question 13

About what percentage of C02 is present in air?

Answer 13

LESS than 1%

Question 14

Explain the term TEMPERATURE GRADIENT

Answer 14

Temperature changes with change in altitude

Question 15

On a warm, still day, the temperature at SEA LEVEL is 28 degrees Celsius. Calculate the approximate air temperature at an altitude of
a) 100m
b) 500 m
c) 1000 m
d) 2000 m
e) 3km
(Look on pg 189 (ACTIVITY 1)

Answer 15

a) 27 degrees Celsius
b) 23 degrees Celsius
c) 18 degrees Celsius
d) 8 degrees Celsius
e) -2 degrees Celsius

Question 16

A light aircraft, flying an an altitude of 1 400 m on a still winter’s day, records an outside air temperature of -3 degrees Celsius.

What is the approximate temperature at sea level that day?

Answer 16

11 degrees Celsius

(1400/100 = 14-3 = 11)

Question 17

To what altitude does the TROPOSPHERE extend?

Answer 17

10km

Question 18

Why are there so many more air particles in the troposphere than in any of the other layers of the atmosphere?

Answer 18

Air is more dense CLOSER to the earth (because of the force of gravity pulling the particles towards the earth)

Question 19

Why do jet airliners usually fly at an altitude of just over 10km?

Answer 19

They fly just outside the troposphere to AVOID changing weather in the troposhere

Question 20

Explain what is meant by the statement that: The temperature gradient is about 1 degree Celsius per 100 meter in still air

Answer 20

A temperature gradient of 1 degree Celsius per 100m in still air means that the air temperature DECREASES by 1 degree Celsius for every 100 m increase in altitude

Question 21

About how much colder is the air at an altitude of 1,700 m than the air at sea level on the same still day?

Answer 21

17 degrees Celsius

Question 22

Explain what the OZONE is

Answer 22

Gas made of 3 oxygen ATOMS

Question 23

Explain ULTRAVIOLET RADIATION

Answer 23

High-energy solar radiation

Question 24

In what part of the STRATOSPHERE is the band of ozone gas located?

Answer 24

Middle (15 - 35km)

Question 25

Why is it important that we are not shielded from all ultraviolet radiation?

Answer 25

Small amount of ultraviolet radiation are necessary because they help our bodies to manufacture Vitamin D

Question 26

List 2 ways in which too much ultraviolet radiation can be harmful to life on EARTH?

Answer 26

Ultraviolet radiation can - cause skin cancer & damage eyesight - cause the death of marine plankton - Affect photosynthesis of plants - Reduce the number of offspring produced

Question 27

Why does the temperature of the stratosphere INCREASE with altitude?

Answer 27

The absorption of UV radiation helps to warm the stratosphere

Question 28

Which layer in the atmosphere is the COLDEST?

Answer 28

Mesosphere

Question 29

What lies beyond the thermosphere?

Answer 29

Interplanetary space

Question 30

What causes the shooting stars that are seen in the mesosphere?

Answer 30

FRICTION between the air particles & FAST moving objects causes it to heat up to burn & make a brief FLASH OF LIGHT

Question 31

What types of solar radiation are absorbed in the lower part of the thermosphere?

Answer 31

UV-radiation and X-rays

Question 32

In which 2 layers of the thermosphere does the temperature ....INCREASE with altitude?

Answer 32

Stratosphere and thermosphere

Question 33

In which 2 layers of the thermosphere does the temperature ....DECREASE with altitude?

Answer 33

troposphere and mesosphere

Question 34

Which layer of the atmosphere has charged particles that are helpful in transmitting radio broadcasts because they reflect RADIO WAVES?

Answer 34

Thermosphere

Question 35

Explain how the atmosphere is divided into 4 layers on the basis of the different temperature gradients in each layer

Answer 35

The 4 layers are: 1) TROPOSPHERE (temp decreases with altitude) 2) STRATOSPHERE (temp increase with altitude) 3) MESOSPHERE (temp decreases with altitude) 4) THERMOSPHERE (temp increase with altitude)