Weather Flashcards
present condition of atmosphere at given location
weather
why do weather change
changes because of unequal distribution of heat from the sun
weather can be broken down into precise and different variables called
atmospheric variables
amount of heat in an atmosphere
air temperature
air temperature is measured by
thermometer
measure of force exerted by air onto surfaces
downward force exerted by air particles
air pressure
what is air pressure expressed in
atmosphere (atm); millimeter of Mercury (mmHg); bar
measuring device of air pressure
barometer
what decreases with altitude
air pressure
amount of moisture in the air (mostly in the form of water vapor)
measure of moisture in the air
humidity
what happens when humidity is at the point of saturation or approaches 100%
it fogs
measuring device of humidity
hygrometer or psychrometer
bodies of condensed water
cloud
measurement of the part of the sky covered with clouds
cloud amount
types of cloud
cirrus - cumulus - nimbus - stratus
fine/feathery; highest in altitude
cirrus
puffy/bulbous; formed by humid and hot air
cumulus
dark cloud from which rain falls; also latin for rain
nimbus
flat and hazy, situated at relatively low altitudes
stratus
when the accumulated droplets in the clouds become too heavy, they fall back to the surface of the earth as what
precipitation
types of precipitation
rain - drizzle - sleet - glaze - snow - hail
either horizontal movement of air or vertical
air movement
it is horizontal; moves from regions of higher air pressure to lower air pressure
wind
measure of how fast the air is travelling horizontally
wind speed
measuring device of wind speed
anemometer
where the air is flowing or blowing into
wind direction
measuring device of wind direction
wind vane
hot air is generally less dense than cold air; hot air descends while cold air ascends
air current
results from unequal rates of cooling and heating of bodies of land and bodies of water
sea breeze and land breeze
during daytime, land is hotter than water because of what
sea breeze
process of sea breeze
land heats up and moves upward
creates a low pressure area
air from the sea moves toward the land to replace the rising air
during night time, land cools faster than air because of
land breeze
process of land breeze
cool air above the land creates a high pressure inland
wind descends and moves towards the sea
low pressure area surrounded by pressure of high area or vice versa
circular wind flow
low pressure surrounded by high pressure
counterclockwise direction
moves in a curved path towards the center
cloudy conditions and precipitation are expected
cyclone
high pressure surrounded by low pressure
clockwise direction
air is blown outward from the center
center of high-pressure regions, fair and clear weather is expected
anti-cyclone
intense disturbances in the atmosphere
storms
begins when warm air rises very rapidly (forming cumulonimbus clouds)
caused by the upward movement of warm, moist air, associated with cumulonimbus clouds
thunderstorms
internal friction builds up static electricity
lightning
violent air disturbances originating from oceans
hurricanes
119 kph and below (wind speed)
cyclone
120 kph and above
hurricane
typhoon range
> 119
severe tropical storm range
89 - 119
tropical storm range
62 - 88
tropical depression
< 61
separates air masses of different densities
front
cloud based near the ground
fog
violent windstorms taking the form of a rotating column of air that extends down a cumulonimbus cloud
tornadoes
