How the atmosphere supports life

Question 1

what percentage of nitrogen, oxygen, carbon dioxide and ozone make up the atmosphere

Answer 1

nitrogen= 78%
oxygen= 21%
carbon dioxide= 0.04%
ozone= 0.000007%

Question 2

define dynamic equilibrium

Answer 2

a state of balance between continuing processes- as one increases so does the other and vice versa

Question 3

list the ways the atmosphere supports life

Answer 3

1) gases for natural processes
2) absorption of electromagnetic radiation from the sun
3) delays the escape of infrared
4) heat distrubituion
5) ocean currents
6) transport of water vapor

Question 4

how do natural gases support life

Answer 4

• synthesis of organic molecules used by living organisms
• nitrogen= proteins
• carbon-carbon dioxide, water and oxygen= lipids,carbohydrates

Question 5

hoe does the absorption of radiation from the sun support life

Answer 5

• biologically damaging solar wind prevented from reaching earth’s surface by the upper atmosphere
• UV light prevented from reaching the surface by various forms of oxygen present in stratosphere = ozone which absorbs UV

Question 6

how does the delayed escape of infra red energy support life

Answer 6

• naturally occurring gases absorb infrared and convert it to heat, therefore increasing the temp of the atmosphere
• reduces the heat loss by conduction from land and oceans

Question 7

how does the atmosphere support life through heat distribution

Answer 7

• most of the suns energy is absorbed by the surface

- warm surface area heats the atmosphere above and heat is distributed to higher latitudes by warm winds

Question 8

explain how the atmosphere supports life through ocean currents

Answer 8

• winds blowing over oceans create currents which carry warm water from tropical regions to higher latitudes
• also carry nutrients

Question 9

what are the origins and roles of UV radiation

Answer 9

• short wave radiation emitted from the sun

- chemical process of the formation and destruction of ozone = dynamic equilibrium

Question 10

what are the origins and roles of infra red radiation

Answer 10

• longwave radiation re-emitted from the surface surface
• insolation
• thermal stratification

Question 11

list from lowest to highest the different levels of the atmosphere

Answer 11

1) troposphere
2) stratosphere
3) mesosphere
4) thermosphere

Question 12

why does the troposphere get cooler with increased altitudes

Answer 12

• as you move higher in altitude in the troposphere it cools as it is moving further away from the heat source of the earths surface-emitting infra-red radiation

Question 13

what does the stratosphere increase in temperature with altitude

Answer 13

• the higher in altitude the more UV radiation

- this means more reactions between ozone and UV which emit heat as a product

Question 14

why does the mesosphere decrease in temp with altitude

Answer 14

• with increased altitude oxygen particles decrease in conc
• therefore there are fewer collisions between molecules
• therefore no heat is given out from the collisions

Question 15

why does temp increase in the thermosphere with increased altitudes

Answer 15

• the increase in altitude the closer you are to the heat source of the sun