Download Name: Core: ______ Date: ______ WEATHER TEST STUDY

Name: ____________________________
Core: ______
WEATHER TEST STUDY GUIDE
Date: _____________
**Study your “Air Masses and Fronts” Notes**
1. What is an air mass? An air mass is an extremely large body of air with the same temperature and humidity
throughout (1000’s of miles).
2. How does an air mass take on its characteristics?
An air mass acquires its temperature and humidity characteristics above an area of land or water known as its source
region. When the air mass sits over a region for several days or longer, it picks up the distinct temperature and humidity
characteristics of that region.
3. What characteristics would the following air masses have (wet or dry; cold or warm)?
maritime tropic (mT): wet and warm
continental tropic (cT): dry and warm
continental polar (cP): dry and cold
maritime polar (mP): wet and cold
4. What is a front? A front is the place where two air masses with different temperature and humidity meet.
5. How does a cold front form? A cold front forms when a cold air mass pushes under a warm air mass, forcing the
warm air to rise. Cold air is heavier and more dense than warm air, so the cold air moves under the warm air.
What kind of weather is associated with a cold front? A cold front is associated with thunderstorms which form as the
moisture in the warm air mass rises, cools, and condenses. As the front moves through, cool, fair weather is likely to
follow.
6. How does a warm front form? A warm front forms when a moist, warm air mass slides up and over a cold air mass.
What kind of weather is associated with a warm front? As the warm air rises, it condenses into a broad area of clouds,
bringing gentle rain or light snow, followed by warmer, milder weather.
7. How does an occluded front form? An occluded front forms when a warm air mass gets caught between two cold air
masses. The warm air mass rises as the cool air masses push and meet in the middle. The temperature drops as the
warm air mass is occluded, or “cut off,” from the ground and pushed upward.
What kind of weather is associated with an occluded front?
An occluded front can bring strong winds and heavy precipitation at the area of the occlusion.
8. How does a stationary front form? A stationary front forms when warm and cold air meet and neither air mass has
the force to move the other. They remain stationary, or “standing still.”
What kind of weather is associated with a stationary front?
Where the warm and cold air meet at a stationary front, clouds and fog form, and it may rain or snow. Can bring days of
clouds and precipitation (often drizzle).
9. Draw the weather symbols for each of the fronts below:
Cold front: blue line with triangles pointing in the direction of the front’s movement
Warm front: red line with semi-circles pointing in the direction of the front’s movment
Occluded front: purple line with semi-circles and triangles pointing in the same direction.
Stationary front: line with red semi-circles and blue triangles pointing in opposite directions.
10. What kind of weather is associated with high-pressure systems?
High-pressure systems are associated with clear skies and calm weather.
11. What kind of weather is associated with low-pressure systems?
Low-pressure systems are associated with Clouds, precipitation, and other “bad weather” such as tropical storms and
tornadoes.
**Study your “Ocean and Climate Relationship” Notes**
12. What is the difference between weather and climate?
Climate: the general weather conditions in an area over a long period of time. Weather is the condition of the
atmosphere at a specific time and place.
13. How does the ocean play a major role in the water cycle?
The majority of the sun’s radiation is absorbed by the ocean. The ocean also holds most of the earth’s water. This means
that most evaporation occurs over the ocean. This constant evaporation increases the temperature and humidity of the
surrounding air to form rain and storms, which are then carried by global winds long distances away. In fact, almost all
rain that falls on land starts in the ocean. The tropics are very rainy because heat absorption (and evaporation) is highest
in this area.
14. What are surface currents and how do they help to regulate the climate?
Surface Currents are continuous movements of ocean water that are caused by surface winds, temperature and salinity
differences, the Earth’s rotation, and tides. Ocean currents act like a giant conveyor belt by transporting warm water
and precipitation from the equator toward the poles and cold water from the poles back to the tropics. This regulates
the uneven distribution of solar radiation reaching Earth’s surface. Without currents, regional temperatures would be
more extreme—super hot at the equator and frigid at the poles—and much less land would be habitable (livable).
15. What is the Gulf Stream and how does it affect coastal cities along the eastern U.S.?
An intense, warm ocean current that moves north from the coast of Florida to Cape Hatteras (NC), and then flows
northeast across the Atlantic Ocean. It is the main conveyor of heat from south to north on the USA east coast. It carries
almost 4 billion cubic feet of warm water per second, an amount greater than that carried by all of the world’s rivers
combined! The east coast of the US and the west coast of Europe are much warmer and wetter (more evaporation and
precipitation) as a result of this!
**Study your “Weather and Water Cycle” Notes**
Define the following terms:
16. Meteorology: the study of the atmosphere and weather, including measurements of temperature, air pressure, wind
speed wind direction, and the amount of moisture in the air.
17. Dew Point: the temperature at which condensation occurs.
18. Relative Humidity: the amount of water vapor the air is holding compared to the amount of water vapor the air can
hold at that temperature. (Remember, warm air can hold more water vapor than cold air.)
19. Evaporation: Heat (energy) is absorbed by liquid water at the surface of the earth and changes into water vapor
(gas).
20. Condensation: water vapor in the atmosphere cools and is converted to liquid water. (Examples: clouds, fog, dew,
condensation on bottles, windows, etc.)
21. Precipitation: water released from clouds in the form of rain, drizzle, snow, sleet, or hail.
22. Transpiration: water is released into the atmosphere as water vapor through small pores in plant leaves.
23. Surface Runoff: the flow of water that occurs when excess storm water, meltwater, or other sources flows over the
earth's surface.
24: Groundwater: the water found underground in the cracks and spaces in soil, sand and rock. It is stored in and moves
slowly through geologic formations of soil, sand and rocks called aquifers.
25. How does hail form?
Hail starts as an ice pellet inside a cold region of a cumulonimbus cloud. The ice pellet gets pushed up by strong updrafts
to the cold region many times, forming a new layer of ice around it every time (layered like an onion.) Eventually, the ice
pellet is heavy enough to fall to the ground.
**Study your “Wind and Coriolis Effect” Notes**
26. The wind blows because parts of the world receive more direct solar radiation, which causes warm air to rise, and
this leads to low pressure (equator). Other parts of the world receive less direct solar radiation, which causes cold air to
sink, and this leads to high pressure (poles). Wind blows from high pressure to low pressure.
27. Describe what causes the breeze to blow from the ocean to the land during the day (sea breeze).
The land heats faster than the ocean. Warm air over the land rises and creates an area of low pressure. Ocean water
does not heat as quickly, so the air there is cooler. Cooler air sinks and creates an area of high pressure. The wind
always blows from H  L, so the during the day the cool ocean breeze blows toward land.
28. Describe what causes the breeze to blow from the land to the ocean at night (land breeze).
The land loses its heat faster than the ocean, so the air over the land is cooler. Cool land air at night sinks and creates an
area of high pressure. Ocean water holds onto its heat longer, so the air above the water is warmer. Warm ocean air
rises and creates an area of low pressure. The wind always blows from H  L, so the at night the breeze blows from the
land to the ocean.
29. What is the Coriolis Effect and what does it do?
The Coriolis Effect is the apparent deflection of a freely moving object like water or air because of Earth's rotation.
The path of a freely moving object appears to curve even though the actual path of the object is straight.
This is because Earth is rotating counter-clockwise beneath the object. So even though the object's path is straight, it
appears to curve. In the Northern Hemisphere, the curve is to the right and in the Southern Hemisphere, the curve is to
the left.
30. Draw an arrow showing how winds blow below as a result of the Coriolis Effect:
From north to south in the Northern Hemisphere:
From south to north in the Northern Hemisphere:
From north to south in the Southern Hemisphere:
From south to north in the Southern Hemisphere:
31. What is the jet stream and how can it affect weather?
The jet stream is a fairly narrow zone of very strong winds in the upper troposphere. When people refer to the jet
stream, they usually mean the polar jet stream (strongest). The jet stream moves or blocks weather systems & can help
in forecasting weather.
32. What are monsoons?
Monsoons are large-scale sea breezes which occur when the temperature on land is significantly warmer or cooler than
the temperature of the ocean; reveres with the season. The summer monsoon brings a lot of rain (flooding) and the
winter monsoon brings drought.
**Study your “Cloud Types” Notes**
33. Fill in the following table with the correct information:
CIRRUS
High or low elevation?
High
Name meaning?
“curl of hair”
Appearance?
Weather that it is
associated with?
CUMULUS
Low
“heap” or “pile”
Thin, white clouds with a
feathery appearance.
Puffy, white clouds with a
cotton-ball appearance.
They generally occur in fair
weather and point in the
direction of air movement
at their elevation.
Dense cirrus clouds are
usually the first sign of an
approaching storm.
Generally, a fair weather
cloud. However, if it grows
tall enough, it can become a
cumulonimbus cloud
(thunderhead).
STRATUS
Low
“spread out”
Layered, thin, sheet-like
clouds (often, gray and
thick); may form fog if low
enough.
Fog, precipitation, drizzle.
34. What would “nimbus” in a cloud name tell you about that cloud?
Nimbus refers to a cloud that produces rain.
35. What is a cumulonimbus cloud? Cumulonimbus clouds form from cumulus clouds that have grown very large; result
in thunderstorms; common name = thunderhead.
36. What is a nimbostratus cloud? Nimbostratus are low, flat clouds that are often associated with steady precipitation
and occur in thick, continuous layers and are often dark gray in color.
**Study your “Thunderstorms, Hurricanes, Tornadoes, and Winter Storms” Notes**
37. What causes lightning?
When the ground is hot, it heats the air above it. This warm air rises. As the air rises, water vapor cools and forms a
cloud. When air continues to rise, the cloud gets bigger and bigger. In the tops of the clouds the water vapor turns to ice.
These small bits of ice bump into each other as they move around and build up electrical charges. Lighter, positively
charged particles form at the top of the cloud & heavier, negatively charged particles sink to the bottom of the cloud.
When the positive and negative charges grow large enough, a giant spark – lightning – occurs between the two charges
within the cloud. This is like a static electricity spark, but much bigger!
38. What causes thunder?
Lightning heats the air so that it expands explosively. The loud clap is thunder.
39. Why is a cold front often associated with thunderstorms?
Cold fronts occur when a cold air mass wedges underneath a warm air mass and quickly pushes the warm air mass up.
As the warm air mass rises it begins to condense to form clouds. As more water vapor is added, the cloud grows into a
cumulonimbus thunderhead. Cold fronts move very quickly, so a thin line of thunderstorms (squall) is produced at the
beginning of a cold front.
40. Why do hurricanes form over the ocean and near the equator?
Around the tropical latitudes (10o - 25oN) the sea surface temperature is 82oF or higher in the summer or autumn.
Warm, humid air over the ocean rises and creates a low pressure cell called a tropical depression with thunderstorms
around it. As more air rises, water vapor continues to condense, releasing energy from latent heat…and the storm gets
stronger. The tropical storm may then build into a hurricane in 2-3 days. The ocean, therefore, adds heat (energy) and
water to the storm.
41. How does the Coriolis Effect affect hurricanes?
When warm air rises over the ocean, it creates an area of low pressure beneath it. In contrast, the areas around this low
pressure center have higher pressures. Air always moves from areas of high pressure to low pressure, so the wind blows
inward toward the low pressure center. However, due to the Coriolis Effect the converging winds curve to their right in
the Northern Hemisphere and to their left in the Southern Hemisphere. This causes the overall rotation of the storm to
rotate counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.
42. What is the “eye of a hurricane”?
At the center of a hurricane is a small area where the air is calm and clear. This is the eye of the hurricane. The eye forms
at the low-pressure center of the hurricane where air is rising upward.
43. What causes tornadoes?
Tornadoes are caused by instability and wind shear. Instability refers to the updrafts and downdrafts caused by warm
air rising from the lower atmosphere and cold air sinking from the upper atmosphere. Wind shear refers to different
speeds of the wind in the upper atmosphere (faster) and lower atmosphere (slower). The spinning air around the
cyclone converges inward toward the thunderstorm, causing it to spin faster and forms a tornado.
44. What causes flooding? Flooding is caused by lot of rain for a long period of time.
45. What are winter storms associated with?
Winter storms are associated with high winds, very low temperatures, and large accumulations of snow.