8th Grade Science-Uddo Chapter 12 and 13 Study guide
Chapter 12 Water Cycle
1.) Know the different steps of the water cycle—review the sheet given in class that we colored and labeled
Structure of the Atmosphere
2.) What is the atmosphere? ____________________________________________________________________________
3.) Complete the following table
Atmospheric Layer (name from Earth outward)
Facts about each layer How does temperature in that layer
4.) What are the boundaries between the layers called? Why do they go by this name?
_________________________________________________________________________________________________
5.) Why is the ozone layer important? ____________________________________________________________________
Composition of the atmosphere:
1.) What are the major gases? (three) What are their respective percentages? _________________________________________________________________________________________________
Air Pressure
1.) What is air pressure? ________________________________________________________________________________________________
2.) Draw arrows and explain why this boy is not being crush by the air pressure acting on him _______________________________________________________________________________________________
3.) What tools and units are used to measure air pressure? ________________________________________________________________________________________________
4.) How does altitude affect air pressure? ________________________________________________________________________________________________
5.) Explain how temperature and density affect air pressure ________________________________________________________________________________________________________________________________________________________________________________________________
Wind
1.) What is wind? _______________________________________________________________________________
2.) What causes wind? ___________________________________________________________________________
3.) What tool is used to measure it? (direction and speed) ______________________________________________
4.) Draw a diagram and explain how land and sea breezes work –info about specific heat, if it happens during the day or
the night, temperature differences, pressure differences, air rising and falling, and draw and arrow showing which direction the wind moves
a. Land Breeze
b. Sea Breeze
Chapter 13 Water in the Atmosphere
1.) Define o Absolute Humidity
__________________________________________________________________________________________ o Relative humidity
__________________________________________________________________________________________
2.) Explain how relative humidity changes with increase or decrease in temperature __________________________________________________________________________________________
3.) Which holds more water, warm or cold air? __________________________________________________________________________________________
4.) If an air mass moves up a mountain, the temperature will go up/down and the relative humidity will go up/down.
5.) What is a sling psychrometer? __________________________________________________________________________________________
6.) What is the wet bulb depression? _______________________________________________________________
7.) The wet bulb temperature will always be equal/lower/greater than the dry bulb temperature.
8.) Explain what is dew point is _________________________________________________________________________________________________
9.) Explain the relationship between relative humidity, air that is saturated and dew point _________________________________________________________________________________________________
Air masses
1.) What is an air mass? ________________________________________________________________________________
2.) What are the two characteristics of air masses? __________________________________________________________
3.) What determines these characteristics? ________________________________________________________________
4.) Complete the table –Give symbol, characteristics and where source region occurs
Arctic (A) Polar (P) Tropical (T)
Maritime (m)
Continental (c)
5.) Define front-
__________________________________________________________________________________________
6.) Complete the table on Fronts
Type of front Air masses involved, movement of air
masses, etc.
Type of weather brought by the front
What is air like after front passes?
Symbol for front
7.) How can you tell what direction fronts are moving? ______________________________________________________
8.) Complete the table on Cyclones and Anticyclones
Pressure System Type of Cyclone Wind movement Clockwise/Counter clockwise
Air rises/sinks Resulting weather
Predicting Weather
9.) What is an isobar _________________________________________________________________________________________________
10.) What is the formula for gradient?
11.) If the gradient is large, the wind speed will be _______________. If the gradient is small, the wind speed will be low.
12.) If the isobars are close together, the wind speed that results will be high/low
13.) What is an isotherm _________________________________________________________________________________________________
14.) Know how to read and interpret station model a. you need to memorize where temperature, dew point, and barometric pressure are listed on the station
model, how to determine the barometric trend, and how to read wind speed and wind direction from the station model
Draw a station model below, with the following data o Temperature: 33°F
o Dewpoint: 27°F
o Pressure: 982.6 mb
o Wind Speed: 5kts
o Wind Direction: NW
o Visibility: 1/4 mi
o Present Weather: Snow Shower
o Barometric Trend: -1.0 mb
o Precipitation (last 6 hours): 1.3 inches
o Cloud Cover: 75%
Practice Questions
1.) In which two temperature zones of the atmosphere does the temperature increase with increasing altitude? a. Troposphere and stratosphere b. Troposphere and mesosphere c. Stratosphere and thermosphere d. Mesosphere and thermosphere
2.) A student found the relative humidity of air to be 65% and the dry bulb temperature recorded was 10oC. What was the wet-bulb temperature reading
a. 5oC b. 7oC c. 3oC d. 10oC
3.) What is the approximate dew point temperature if the dry-bulb temperature is 26oC and the wet-bulb temperature is
20oC? a. 11oC b. 20oC c. 17oC d. 7oC
4.) The air outside a classroom has a dry-bulb temperature of 10oC and a wet-bulb temperature of 4oC. What is the
relative humidity of this air? a. 1% b. 14% c. 33% d. 54%
5.) Which graph best represents the change in air pressure as air temperature increases at Earth’s surface?
6.) In the diagram below, arrows represent air movement near an ocean coastline on a summer afternoon.
Compared to the air over the ocean, the air over the land has
a. A lower temperature and a lower barometric pressure b. Lower temperature and higher barometric pressure c. Higher temperature and lower barometric pressure d. Higher temperature and higher barometric pressure
7.) Locations A and B on the map of North America below are source regions for air masses.
Compared to the air mass formed at location B, the air mass formed at location A will normally be a. Cooler and wetter b. Warmer and wetter c. Cooler and drier d. Warmer and drier
8.) A weather station records a barometric pressure of 1013.2 millibars. Which diagram below would best represent this
weather station on a weather map
9.) The air-pressure field map below represents a high-pressure system over the central United States. Isobars show the air pressure, in millibars. Letters A through E represent locations on Earth’s surface Between which two locations is the wind speed greatest?
a. A and B b. B and C c. C and D d. D and E
10.) Base your answer to the following question on the weather map below. The map shows a low-pressure system and some atmospheric conditions at weather stations A, B, and C. Which cross section best represents the air masses, air movement, clouds and precipitation occurring behind and ahead of the warm front located between stations A and B?