UNIT 4 - Atmosphere Vocabulary
PART 1
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Storm surge – abnormal rise of the sea along a shore as a result of strong winds
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local winds – winds causes by either topographic effects or by variations in surface
composition (land and water) in the immediate area
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cyclones – low-pressure center characterized by a counterclockwise flow of air in the
Northern Hemisphere
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wind – movement of air from an area of high pressure to an area of low pressure
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Coriolis Effect – apparent deflective force of Earth’s rotation on all free-moving objects,
including the atmosphere and oceans; to the right in the Northern Hemisphere
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dew point – temperature to which air has to be cooled in order to reach saturation
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front – the boundary between two adjoining air masses having contrasting characteristics
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heat – thermal energy transferred from one object to another
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monsoons – seasonal reversal of wind direction associated with large continents, especially
Asia; winter = wind from land to sea, summer = wind from sea to land
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rotation – spinning of a body, such as Earth, about its axis (day)
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revolution – the motion of one body about another, such as the Earth moving in its orbit
about the Sun (year)
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latent heat – energy absorbed or released during a change in state
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temperature – measure of the average kinetic energy of individual atoms or molecules in a
substance
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weather – the state of the atmosphere at any given time and place
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absorption – interception of radiant energy by objects, such as Earth’s atmosphere
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anticyclones – high-pressure center characterized by a clockwise flow of air in the
Northern Hemisphere
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climate – observations of weather collected over many years that help describe a place or
region
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orographic lifting – pushing up of air by elevated terrain (such as mountains)
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relative humidity – ratio of the actual amount of water vapor in a parcel of air compared to
the amount of water vapor it can actually hold
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stratosphere – about 12km to 50km above Earth’s surface; temperature increases as you go
higher (due to ozone layer); ozone layer is found here
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troposphere – from Earth’s surface up to about 12km; temperature decreases as you go
higher; layer where most weather events occur
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exosphere – most outer layer of Earth’s atmosphere; mixed layer between Earth’s
atmosphere and space
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thermosphere – about 85km to 100km above Earth’s surface; temperature increases as you
go higher (due to solar radiation)
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mesosphere – about 50km to 85km above Earth’s surface; temperature decreases as you go
higher
PART 2
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air pressure - exerted in all directions, when the air pressure pushing down on an object
exactly balances the air pressure pushing up on the object
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barometer - a device used for measuring air pressure
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pressure gradient - the spacing of isobars that shows the pressure changing occurring over
a given distance
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jet streams – fast moving rivers of air at high altitudes
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trade winds - two belts of winds that blow almost constantly from easterly directions
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polar easterlies - winds that blow from the polar high toward the subpolar low
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polar front - the interaction of these warm and cool air masses
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westerlies - air traveling towards the poles
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prevailing wind - when the wind consistently blows more often from one direction than
from any other; from west to east in the continental United States
anemometer – instrument commonly used to measure wind speed
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El Nino - episodes of ocean warming that affect the eastern tropical Pacific; causes dry
areas to receive more rain than usual and wet areas to be dryer than usual; often occurs in
7 to 10 year cycles
PART 3
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air mass - an immense body of air that is characterized by similar temperatures and
amounts of moisture at any given altitude
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warm front - forms when warm air moves into an area formerly covered by cooler air
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cold front - forms when cold, dense air moves into a region occupied by warmer air
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stationary front – occurs when air flow is almost parallel to the line of the front
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occluded front – occurs when an active cold front overtakes a warm front
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thunderstorm – a storm that generates lightning and thunder; frequently produce gusty
winds, heavy rain, and hail
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tornado – a violent windstorm that takes the form of a rotation column of air called a
vortex which extends downward from a cumulonimbus cloud
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hurricane – a whirling tropical cyclone with winds of at least 119kph; occur most often in
late summer
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global warming – an increase of global temperatures due to increased levels of carbon
dioxide and other greenhouse gases