Atmosphere Study Guide
Composition of the Atmosphere
Name 2 functions of the atmosphere: _protection from solar radiation & regulating Earths temperature__
Earth’s atmosphere makes Earth livable in many ways:
 Protects/sustains life on Earth
 Provides oxygen for breathing
 Carbon dioxide for plants (photosynthesis)
 Water vapor for precipitation
 Ozone layer absorbs ultraviolet solar radiation
Be able to read a circle graph.
Describe the difference between:
Major vs Trace gases (give examples of each)
___Major gases are gases that make up more than 1% of the atmosphere like Oxygen and
Nitrogen. Trace gases are less than 1% like Argon, CO2, methane and Neon___
Permanent vs Variable gases (give examples of each)
__Permanent Gases have a constant amount in the atmosphere anywhere on the globe like Neon,
Nitrogen, Carbon Dioxide, and Oxygen. Variable gases are constantly changing from location to
location. Water vapor is an example of a variable gas (think of a desert vs. a humid tropical rain
forest._
What is the most common gas in the atmosphere? ____Nitrogen ___
What is the second most common gas in the atmosphere?_______Oxygen ______
How has the Earth’s atmosphere changed compared to Earth’s early atmosphere? Why did these
changes occur?
______Early Earth had no oxygen and had lots of carbon dioxide. Once photosynthetic
organisms (cyanobacteria, algae, plants) evolved on Earth oxygen formed and CO2 was reduced.
Photosynthesis takes in CO2 and water and produces sugar (glucose) & oxygen.________
Heat in the Atmosphere
Review the indirect/slanted and direct rays activity.
What part(s) of the globe receive direct rays? ____equator__________________
What part(s) of the globe receive indirect/or slanted rays? ______poles_________
Do direct or slanted rays produce more intense heat?__________direct ___________
Direct and slanted solar rays cause the uneven heating of Earth’s surface. Direct rays cover less area, but
would be warmer over time. Slanted rays cover more area/space, but would not be as warm as direct rays.
Describe reflection, scattering, and the absorption of heat.
reflection-_ to redirect something that strikes a surface, especially light, sound, or heat, usually
back toward its point of ___
absorb- to take in heat (thermal energy). Temperature will increase.
Scatter- to separate light and move suddenly in different directions,
Give examples of surfaces that reflect more heat, and absorb more heat.
Which type of surface will get hotter?
__All surface reflect AND absorb heat. Surfaces like the ocean, asphalt, sand and buildings
absorb high levels of heat and get hotter. Ice, snow, & mirrors reflect more heat.__
Describe the greenhouse effect. (HINT: It is natural. Do not use the words pollution or global warming.)
______The atmosphere absorbs heat warming the Earth. Some heat escapes.
The thicker the atmosphere is with greenhouse gases like water vapor carbon dioxide
and methane the more heat gets trapped. An enhanced (stronger) greenhouse effect
can warm the globe.
Heat transfer occurs through 3 methods what are these methods?
_____________Radiation, Conduction, Convection_________________________
Draw, label & describe a convection current: (use some form of the word density in your description)
Convection: circulation of molecules in gases or liquids
due to differences in density. This only works in liquids and gases
because it requires matter that can move or flow. Example:
magma in the mantle. Density is a measure of how much mass
there is in a volume of a substance. If an object is less dense than
water, it will float to the top. If an object is more dense than
water, it will sink to the bottom.
Define & give an example of conduction:_ Conduction: the transfer of heat between molecules that are
in direct, physical contact with one another. Example: spoon gets hot in hot soup
Define & give an example of radiation:__ Radiation: energy that can travel through empty space in the
form of waves. Example: fireplace, french-fry warmer
When heat is __ (absorbed
back into the environment.
/
reflected) _ by a surface it can later be _____________________
Layers of the Atmosphere
Know the order and characteristics of each layer.
Describe and interpret a graph of the temperature of the atmosphere at different altitudes.
Troposphere: lowest, most dense, thinnest layer of the atmosphere; where we live
Stratosphere: where jets fly; contains ozone layer
Mesosphere: coldest layer, where meteor showers occur
Thermosphere: air is very thin; space shuttles orbit here
Ionosphere: auroras(light displays), made of ions(charged particles), AM radio waves
Exosphere: outer space
Does this layer increase (I) or decrease (D) in temperature with increasing altitude?
Troposphere ___D_____
Stratosphere ___I____ Mesosphere __D_____ Thermosphere____I____
Why does this pattern occur? What makes some layers get colder and others get hotter? BE SPECIFIC.
___Different gases in each layer.
Troposphere becomes less dense as altitude increases and it is less able to absorb heat.
Stratosophere has an ozone layer which absorbs UV light adding to heat.
Mesopshere does not absorb heat.
Thermosphere is closer to the sun. The ionosphere creates ions and this creates heat
__________________________________________________________________________
What happens to temperature at the “pauses”:__ At a pause in the atmosphere, such as the
tropopause, temperature stops increasing/decreasing.
What are the 2 layers of the thermosphere?________Ionosphere and Exosphere________
Where is the ozone layer and what does it do?__Stratosphere. Blocks harmful UV rays
Water Cycle
Review the Cloud Making Lab and Water Cycle Game.
Describe and label the steps in the water cycle.
Label: Sun, condensation, precipitation, runoff, ground water, transpiration, respiration, evaporation, excretion
Condensation is the process by which water vapor changes to liquid to water.
Evaporation is the process by which liquid water turns to water vapor (gas).
Groundwater is water that is held in rock layers under the surface of the Earth.
Precipitation is the process by which water falls from the atmosphere to Earth’s surface.
Runoff is water flowing over the surface of the Earth.
Transpiration is the process by which water evaporates from the leaves of plants.
Respiration: plants and animals release water vapor when they consume sugar.
Excretion: The release of water as waste (urine, sweat)