Chapter 12 Meteorology
air mass
A large parcel of air that takes on the characteristics of the area over which it forms is an...
warm front
Advancing warm air that displaces cold air.
short term
All forecasts are more reliable in the _____ _____
temperature and humidity
An air mass takes on its source region's...
analog forecast
Another type of forecast, the _____ _____ involves comparing current weather patterns to patterns that took place in the past.
occluded front
Cold air mass that moves rapidly and overtakes a warm front
cold front
Cold, dense air that displaces warm up, forcing it up.
northeast
In the northern hemisphere, these winds flow from the _____ to the southwest.
southwest
In the northern hemisphere, these winds flow from the northeast to the ______.
true
Long-term variations in weather for a particular area make up the CLIMATE of the area
true
METEOROLOGY is the study of atmospheric phenomena
oceans
Maritime air masses originate over...
jet streams
Narrow bands of fast, high-altitude, westerly winds called ______ _____ flow at the boundaries between wind zones in the middle latitudes.
front
Narrow region separating two air masses of different densities.
low pressure
Pressure system that is associated with cloudy weather and precipitation
Low Pressure System
Rising air
High Pressure System
Sinking air
Coriolis Effect
The _____ _____deflects moving air to the right in the northern hemisphere and to the left in the southern hemisphere.
rotation
The cause of this (Coriolis Effect) is Earth's_____
trade winds
The first wind systems, at 30 degrees latitude north and south is known as the _____ _____
polar jet stream
The most important jet stream, the _____ _____ _____, separates the polar easterlies from the prevailing westerlies.
prevailing westerlies
The second wind system, called the _____ _____, flows between 30 degrees and 60 degrees latitude north and south of the equator.
polar easterlies
The third wind system, the _____ _____, lies between the poles and 60 degrees latitude.
false, directly
The tropics are hotter than the poles because the sun strikes this area of Earth more INDIRECTLY
North America
These winds are responsible for the movement of many weather systems across much of ______ _____
low pressure
These winds from both hemispheres converge at the equator. They are forced upward, creating an area of _____ _____
intertropical convergence zone
This area of convergence near the equator is the _____ _____ _____
stationary front
Two air masses that meet and do not advance
false, atmosphere
Weather is the current state of the LITHOSPHERE
air mass modification
When an air mass travels over land or water that has different characteristics than those of its source region, it undergoes...
station model
a record of weather data for a particular site at a particular time
High Pressure System
air flows away from center
Low Pressure System
air flows towards center
High Pressure System
air moves clockwise in northern hemisphere
Low Pressure System
air moves counterclockwise in northern hemisphere
true
an isotherm is a line that connects points of equal temperature
radiosonde
balloon-borne package if sensors that gathers upper-level weather data
Doppler effect
change in pitch frequency that occurs due to the relative motion of a wave
Low Pressure System
clouds and precipitation
false
contour lines are lines of equal temperature
infrared imagery
detects different frequencies, used to map cloud cover or surface temperatures
High Pressure System
fair weather
barometer
instrument that measures air pressure
hygrometer
instrument that measures relative humidity
thermometer
instrument that measures temperature
anemometer
instrument that measures wind speed and direction
true
isobars that are far apart indicate a small difference in pressure and light winds
true
isotherms are used to identify temperature gradients and, consequently, frontal systems
true
lines of equal pressure are called isobars
radar
radio detecting and ranging
weather satellite
sees clouds
weather radar
sees precipitation, snow/rain/etc.
digital forecast
A _____ _____ relies on numerical data.
long term
Forecasts become less reliable as they attempt to predict ____ _____ weather changes.