Earth and Beyond (Assignment 4) Flashcards
Why is the atmosphere so important for life on Earth?
- 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
Name the different gasses in the atmosphere
Nitrogen - 78%
Oxygen - 21%
Carbon dioxide - 0.03%
Other - 0.97%
Name the different layers of the ATMOSPHERE and their depth
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
What do you find in the TROPOSHERE
This is where plants and animals live
Lots of weather changes
What do you find in the STRATOSPHERE
Aeroplanes fly here
Ozone layer (15-50 km)
What do you find in the MESOSPHERE
Shooting stars and meteors
What do you find in the TERMOSPHERE
ISS (International Space Station) - (320-380 km)
Hubble space telescope (595km)
GPS (20 000 km)
Polar lights
Weather and TV Satellites
What keeps the gas particles of the atmosphere from drifting off into space?
Gravitational forces
What WORD describes the extent to which the particles of a gas are CROWDED closely together?
Density
Why is the DENSITY of air greater at sea level than at a high altitude?
-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
Name the MAIN GASES in the air
1) Nitrogen
2) Oxygen
What approximate proportions of air ae made up of these 2 gases?
78% nitrogen
21% oxygen
About what percentage of C02 is present in air?
LESS than 1%
Explain the term TEMPERATURE GRADIENT
Temperature changes with change in altitude
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)
a) 27 degrees Celsius
b) 23 degrees Celsius
c) 18 degrees Celsius
d) 8 degrees Celsius
e) -2 degrees Celsius
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?
11 degrees Celsius
(1400/100 = 14-3 = 11)
To what altitude does the TROPOSPHERE extend?
10km
Why are there so many more air particles in the troposphere than in any of the other layers of the atmosphere?
Air is more dense CLOSER to the earth (because of the force of gravity pulling the particles towards the earth)
Why do jet airliners usually fly at an altitude of just over 10km?
They fly just outside the troposphere to AVOID changing weather in the troposhere
Explain what is meant by the statement that: The temperature gradient is about 1 degree Celsius per 100 meter in still air
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
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?
17 degrees Celsius
Explain what the OZONE is
Gas made of 3 oxygen ATOMS
Explain ULTRAVIOLET RADIATION
High-energy solar radiation
In what part of the STRATOSPHERE is the band of ozone gas located?
Middle (15 - 35km)
Why is it important that we are not shielded from all ultraviolet radiation?
Small amount of ultraviolet radiation are necessary because they help our bodies to manufacture Vitamin D
List 2 ways in which too much ultraviolet radiation can be harmful to life on EARTH?
Ultraviolet radiation can
- cause skin cancer & damage eyesight
- cause the death of marine plankton
- Affect photosynthesis of plants
- Reduce the number of offspring produced
Why does the temperature of the stratosphere INCREASE with altitude?
The absorption of UV radiation helps to warm the stratosphere
Which layer in the atmosphere is the COLDEST?
Mesosphere
What lies beyond the thermosphere?
Interplanetary space
What causes the shooting stars that are seen in the mesosphere?
FRICTION between the air particles &
FAST moving objects causes it to heat up to burn &
make a brief FLASH OF LIGHT
What types of solar radiation are absorbed in the lower part of the thermosphere?
UV-radiation and X-rays
In which 2 layers of the thermosphere does the temperature ….INCREASE with altitude?
Stratosphere and thermosphere
In which 2 layers of the thermosphere does the temperature ….DECREASE with altitude?
troposphere and mesosphere
Which layer of the atmosphere has charged particles that are helpful in transmitting radio broadcasts because they reflect RADIO WAVES?
Thermosphere
Explain how the atmosphere is divided into 4 layers on the basis of the different temperature gradients in each layer
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)
