Chapter 7: Planetary Atmospheres: Earth and Other Terrestrial Worlds

Question 1

Size of Earth’s Atmosphere

Answer 1

10 km thick
-consists mostly of molecular nitrogen and oxygen

Question 2

pressure and density relation with altitude

Answer 2

pressure and density decrease with altitude because the weight of overlying layers is less

Question 3

Earth’s pressure at sea level

Answer 3

101.325 kPa
14.7lb per sq inch
1 bar

Question 4

where does the atmosphere end?

Answer 4

there is no clear upper boundary to where the atmosphere ends

Question 5

what is considered space?

Answer 5

altitudes more than 100 km
- small amounts of gas are present even above 300 km

Question 6

how does an atmosphere determine whether liquid water can exist on surface?

Answer 6

creates pressure that determines existence

Question 7

how does an atmosphere create a magnetosphere

Answer 7

-absorbs and scatters light
-creates wind, weather, and climate
-interacts with solar wind

Question 8

what is a magnetosphere

Answer 8

a region of space around a planet in which the planet’s magnetic field can affect charged particles

Question 9

greenhouse effect

Answer 9

visible light passes through the atmosphere and warms a planet’s surface

Question 10

earth surface temp with no greenhouse gases

Answer 10

well below the freezing point of water

Question 11

how does the greenhouse effect trap heat?

Answer 11

• atmosphere absorbs infrared light from surface, trapping heat

Question 12

why does burning fossil fuels increase the greenhouse effect on Earth?

Answer 12

burning releases carbon dioxide into the atmosphere

Question 13

what determines a planet’s surface temperature?

Answer 13

determined by the balance between energy from sunlight it absorbs and energy of outgoing thermal radiation