Atmosphere

Question 1

Earth’s axis of rotation and the plane of ecliptic are…

Answer 1

parallel

Question 2

axial tilt

Answer 2

angle of Earth’s axis of rotation

• relative to the normal to the orbital plane
• 23.4 degrees

Question 3

obliquity (of tilt)

Answer 3

• change in axial tilt
• 22 to 24.5 degrees
• period of 41 000 years

Question 4

axial precission

Answer 4

wobbling caused by gravitational attraction

• gravitational attraction from Sun and Moon
• period of 100 000 years

Question 5

Aphelion

Answer 5

• furthest from the sun (Summer in NH)

- July 4

Question 6

Periphelion

Answer 6

• closest to sun (Winter NH)

- Jan 4

Question 7

Earth’s Oscillation Period and Shape

Answer 7

• oscillates between circle and ellipse

- period of 100 000 years

Question 8

Earth’s Atmosphere Size

Answer 8

480 km

Question 9

Atmosphere Formation

Answer 9

• planet cooled at surface
• dense material went to the center
• lighter materials flowed to top -> created layers
• gases from inside out gassed the atmosphere (volcanic eruptions and collisions)

Question 10

Volcanic Outgassing

Answer 10

• lots of water (50-60%)
• quarter CO2 (24%)
• sulfur, 13% etc.

Question 11

Formation of the Ozone

Answer 11

• O2 is produced, UV radiation splits to create ozone (O3)

- ozone layer also created (UV shield)

Question 12

Main Reason for Seasons:

Answer 12

tilt!!

Question 13

Modern Atmosphere Composition

Answer 13

-70% N2
-21% Oxygen
-Ar 1%
-CO2 0.04%
….

Question 14

Thermosphere

Answer 14

• 80 - 550 km
• N, O, and smaller particles in Ionosphere absorb radiation from the sun
• become electrically charged
• absorbs cosmic rays (gamma, x, shorter)
• gases are layered by weight (gravity)

Question 15

Lower layers of Thermosphere

Answer 15

• 0-80 km
• chemically uniform mix of gases
• absorbs UV rays
• H20y variations near surface

Question 16

Density of Atmosphere

Answer 16

• density and pressure DECREASES with altitude
• troposphere contains 90% of mass
• above 50 km. 0.001% of mass

Question 17

Heterosphere (80-?)

Answer 17

• 80 km to 500 km
• 0.001% of mass
• distinct layers of gas due to gravity

Question 18

Homosphere

Answer 18

• 0 km to 80 km
• uniformly mixed
• ozone layer

Question 19

Thermosphere (temperature)

Answer 19

• 80 km to 480 km (thermopause)
• temperature INCREASES with altitude
• no heat conduction, high energy solar radiation

Question 20

Mesosphere (temperature)

Answer 20

• 50 km to 80 km

- temperature DECREASES with altitude (-90 C)

Question 21

Stratosphere (temperature)

Answer 21

• 18 km to 50 km
• temperature INCREASES with altitude
• from -57 C to 0 C at stratopause
• absorption of UV by ozone

Question 22

Troposphere (temperature)

Answer 22

• surface to 18 km
• decreases with altitude
• normal lapse rate of 6.5 degrees C /km