Chapter 16: The Atmosphere: Composition, Structure, & Temperate Flashcards
(28 cards)
Weather, what is it?
- Occurs over a short period of time
- Constantly changing
- Refers to state of atmosphere
Climate, what is it?
- Occurs over a long period of time
* Composite of weather conditions over many years
Regularly measured properties of weather and climate?
- temp
- humidity
- cloudiness
- precipitation
- air pressure
- wind speed and direction
The atmosphere is made up of what components?
- Nitrogen -78%
- Oxygen -21%
- Argon and other gases- .93%
- Carbon Dioxide -.036%
Three components is the air
1) Water vapor
2) Aerosols
3) Ozone
What is water vapor?
- Varies considerably
- 4% of air’s volume
- Forms cloud and precipitation
- Absorbs heat energy from Earth
What is aerosols?
- Tiny sold and liquid particles (dust, pollen, ect)
- Particles reflect sunlight
- Helps to color sunrises and sunsets
What is an ozone?
- Form of oxygen that combines 3 oxygen atoms into each molecule
- Absorbs harmful ultraviolet radiation from sun
Explain Pressure Changes
- Pressure is the weight of the air
- Average sea level pressure about 14.7 pounds per square inch
- Pressure decreases with altitude (90% found within 10 miles of Earth’s surface)
What is a Radiosonde?
an instrument carried aloft, by a weather balloon to gather and transmit meteorological data
*balloon expands as it rises/ pressure decreases / when popped sends parachute down and then it is tracked on a GPS
The layers of the atmosphere is based on what?
temperature
What is the Troposphere?
- The bottom layer of the atmosphere
- Temp decrease w/ altitude called environmental lapse rate
- The outer boundary is called the “tropopause”
What is the Stratosphere?
- Between 12 km to 50 km above earth. aka below middle
- Temp increases here where the ozone layer is concentrated
- Outer boundary is called the stratopause
What is the Mesosphere?
- Between 50 km to 80 km above earth. aka middle
- Temp decreases steadily; coldest temps occur here
- Outer boundary called mesopause
What is the Thermosphere?
- does not have well-defined upper limit.
- gases are moving at high speeds
- temp starts to increase dot to high energy solar radiation. aka highest part
Two motions of the Earth
1) Rotation-
Earth fully rotates on axis every 24hrs
Produces daily cycle of day & night
2) Revolution-
Movement of earth on orbit around the sun.
1 revolution/ year
Why do we experience seasons on earth?
Because of the tilt of the Earth axis!
Happens when the sun hits the earth
A result of Earth’s changing orientation to the Sun is what?
Seasons!
The Earth’s axis is at
23.5 degrees
When does the Summer Solstice happen for us?
- June 21, most hours of daylight
- **Earth is tilted on angle towards the sun
- Suns vertical rays are located at the Tropic of Cancer
When does the Winter Solstice happen for us?
- December 21, fewest hours of daylight
- Earth is tilted away from the sun
- Suns vertical rays are located at the Tropic of Capricorn
When does the Fall (Autumnal) equinox and Spring (Vernal) equinox happen for us?
FALL September 21
SPRING March 21
- Days and nights are equal
- Suns vertical rays are located at the equator
Three mechanisms of heat transfer
1) Conduction: transfer of heat through molecular activity
2) Convection: transfer of heat through mass movement
3) Radiation: doesn’t need a medium to travel. This is how heat from the Sun reaches our planet.
Possible effects when radiation strikes and object
1) Reflection (% of radiation reflected)
2) Scattering
3) Absorption
What is reflection?
the process of when light bounces back from an object at the same angle and intensity, which it hit the surface
