ATMS 120 UIUC Exam 1 questions well
answered
Top of the earth's atmosphere - correct answer ✔✔ toa = 120 km (75 miles)
99.9% below 36 miles
Air density and height - correct answer ✔✔ air density decreases rapidly with height
Primary gasses in earth's atmosphere - correct answer ✔✔ water vapor
nitrogen - most abundant (78%)
methane
ozone
carbon dioxide
oxygen - 2nd most abundant (21%)
Argon - almost all of last 1%
How does the earth keep warm - correct answer ✔✔ 1. all gasses are almost completely
transparent to sun's peak energy output (visible light)
2. O2/N2 are also transparent to earth's peak energy output (thermal infrared energy), but
greenhouse gasses are not, so they efficiently absorb this energy/warm the atmosphere
Average global surface air temperature without greenhouse gasses - correct answer ✔✔ 0
degrees F
Average global surface air temperature with greenhouse gasses - correct answer ✔✔ 59
degrees F
,Difference between weather and climate - correct answer ✔✔ weather is highly variable day-to-
day/"normal" for temperature to be 15 degrees F above/below average temperature
climate is the average of weather (typically a 30 year average)
When are records for weather/climate set? - correct answer ✔✔ when temperatures are 4+
standard deviations away from mean
Definition of temperature - correct answer ✔✔ a measure of the average speed (kinetic energy)
of all the molecules in a substance (solid, liquid, gas)
Relationship between temperature/density - correct answer ✔✔ higher the air temperature,
the faster the air molecules move
faster the molecules move, the more space they will need to move around
warming the air will cause it to expand
cooling the air will cause it to contract
so warm air is less dense than cold air
What causes temperature variations? - correct answer ✔✔ 1. the angle of the sun's rays/length
of daylight hours are not constant
2. the earth is covered with many different surface types that absorb energy differently
Summer solstice - correct answer ✔✔ june 21st
sun's rays are direct on tropic of cancer
most daylight hours
Autumnal equinox - correct answer ✔✔ september 21st
, sun's rays are direct on equator
12 hours daylight/12 hours night
Winter solstice - correct answer ✔✔ december 21st
sun's rays direct on tropic of capricorn
least daylight hours
Vernal equinox - correct answer ✔✔ march 21st
sun's rays are direct on equator
12 hours daylight/12 hours night
What causes seasonal variations in temperature? - correct answer ✔✔ the tilt of the earth on
its axis causes the sun's rays to become more (or less) direct which concentrates (or disperses)
the sun's energy throughout the year
Latitude/temperature variation - correct answer ✔✔ the greater the latitude, the greater the
yearly variation in temperature
winter - low sun angle, fewer daylight hours, sun's path through atmosphere is long
summer - high sun angle, more daylight hours, sun's path through the atmosphere is short
Temperature inversion - correct answer ✔✔ any layer of the atmosphere where the
temperature increases with height
What layer of the atmosphere does weather occur in? - correct answer ✔✔ troposphere
80% of the atmosphere mass is in the troposphere
Pressure - correct answer ✔✔ force per unit area applied by the air (mb)
answered
Top of the earth's atmosphere - correct answer ✔✔ toa = 120 km (75 miles)
99.9% below 36 miles
Air density and height - correct answer ✔✔ air density decreases rapidly with height
Primary gasses in earth's atmosphere - correct answer ✔✔ water vapor
nitrogen - most abundant (78%)
methane
ozone
carbon dioxide
oxygen - 2nd most abundant (21%)
Argon - almost all of last 1%
How does the earth keep warm - correct answer ✔✔ 1. all gasses are almost completely
transparent to sun's peak energy output (visible light)
2. O2/N2 are also transparent to earth's peak energy output (thermal infrared energy), but
greenhouse gasses are not, so they efficiently absorb this energy/warm the atmosphere
Average global surface air temperature without greenhouse gasses - correct answer ✔✔ 0
degrees F
Average global surface air temperature with greenhouse gasses - correct answer ✔✔ 59
degrees F
,Difference between weather and climate - correct answer ✔✔ weather is highly variable day-to-
day/"normal" for temperature to be 15 degrees F above/below average temperature
climate is the average of weather (typically a 30 year average)
When are records for weather/climate set? - correct answer ✔✔ when temperatures are 4+
standard deviations away from mean
Definition of temperature - correct answer ✔✔ a measure of the average speed (kinetic energy)
of all the molecules in a substance (solid, liquid, gas)
Relationship between temperature/density - correct answer ✔✔ higher the air temperature,
the faster the air molecules move
faster the molecules move, the more space they will need to move around
warming the air will cause it to expand
cooling the air will cause it to contract
so warm air is less dense than cold air
What causes temperature variations? - correct answer ✔✔ 1. the angle of the sun's rays/length
of daylight hours are not constant
2. the earth is covered with many different surface types that absorb energy differently
Summer solstice - correct answer ✔✔ june 21st
sun's rays are direct on tropic of cancer
most daylight hours
Autumnal equinox - correct answer ✔✔ september 21st
, sun's rays are direct on equator
12 hours daylight/12 hours night
Winter solstice - correct answer ✔✔ december 21st
sun's rays direct on tropic of capricorn
least daylight hours
Vernal equinox - correct answer ✔✔ march 21st
sun's rays are direct on equator
12 hours daylight/12 hours night
What causes seasonal variations in temperature? - correct answer ✔✔ the tilt of the earth on
its axis causes the sun's rays to become more (or less) direct which concentrates (or disperses)
the sun's energy throughout the year
Latitude/temperature variation - correct answer ✔✔ the greater the latitude, the greater the
yearly variation in temperature
winter - low sun angle, fewer daylight hours, sun's path through atmosphere is long
summer - high sun angle, more daylight hours, sun's path through the atmosphere is short
Temperature inversion - correct answer ✔✔ any layer of the atmosphere where the
temperature increases with height
What layer of the atmosphere does weather occur in? - correct answer ✔✔ troposphere
80% of the atmosphere mass is in the troposphere
Pressure - correct answer ✔✔ force per unit area applied by the air (mb)
