meteorology Flashcards
What distributes heat around the world and maintains the average temp of different regions?
Ocean currents and global winds
Not all areas of the Earth are heated evenly due to?
the axial tilt of Earth and its spherical shape
The amount of energy the Earth receives and the amount Earth radiates back into space
the same amount
weather
short term variations in atmosphere phenomena that interact and affect the environment and life on Earth
climate
long term average variations in weather for a particular are
how many years to define a climate
30 years
electrometeor
thunder and lightning
lithometeor
smoke, haze, dust, and suspended particles
Hydrometeor
cloud droplets and precipitation
What kind of precipitation occurs in an occluded front
strong winds and heavy rain
What happens to air in an occluded front
rapidly advancing cold air mass overtakes warm front, forcing warm air up and making cold air collide with other cold front
what kind of precipitation occurs in a stationary front?
light rain and wind, small temperature and pressure difference
why can’t stationary fronts move each other
neither is strong enough over the other to move out of the way
What happens to air in a stationary front?
two air masses meet but neither advances
what kind of precipitation occurs in a warm front?
light precipitation for days, can be over 200 miles long, low-level stratus
what happens to air in a warm front
warm air displaces cold, produces cirrus clouds, slides up over cold air
what kind of precipitation occurs in a cold front
heavy rain, thunder storms, short duration, cumulonimbus clouds form
what happens to air in a cold front
fast cold air pushes warm air away, causing it to move up and make clouds, normally follow warm fronts, difficult to predict or foresee
wind
the horizontal movement of air from high to low pressure
what would happen if Earth did not rotate
surface winds would blow from the poles to the equator
Coriolis effect
effect of the Earth’s rotation on fluids moving over the surface
where does the Coriolis effect deflect winds in the northern hemisphere
to the right
where does the Coriolis effect deflect winds in the southern hemisphere
to the left
where are the poles and what pressure
90 degrees north and south, high pressure
where is the polar front and what pressure
60 degrees north and south, low pressure
where are the horse latitudes and what pressure
30 degrees north and south, high pressure
inter tropical convergence zone
0 degrees, low pressure, equator, drifts north and south with the seasons as it follows the highest temperatures on Earth
What creates global wind systems
the Coriolis effect and heat imbalance
what are winds named by?
where they come from
polar easterlies
60-90 north and south, northeast to southwest in northern hemisphere, southeast to northwest in southern hemisphere
prevailing westerlies
30-60 north and south, southwest to northeast in northern hemisphere, northwest to southeast in southern hemisphere
trade winds
0-30 north and south, northeast to southwest in northern hemisphere, southeast to northwest in southern hemisphere
doldrums
equator, upward air flow no winds)
jet streams
10.7-12.2 in altitude, west to east in northern and southern hemisphere, 400km/hour
polar jet streams
high altitude, 40-60 north and south, west to east in northern and southern hemisphere, can veer north and south
subtropical jet streams
high altitude 20-30 north and south, west to east northern and southern hemisphere, weather follows path of jet stream
pressure systems
sinking and rising air combined with Coriolis
effect results in rotating high and low pressure systems
low pressure system (vacuum)
air spirals in towards low pressure and rises, results in storms, spins counterclockwise low in northern hemisphere, clockwise in southern hemisphere
high pressure systems (leafblower)
air flows out of high pressure and sinks, results in clear weather, spin clockwise around high northern hemisphere, counter-clockwise in southern hemisphere
what is an air mass
a large volume of air that has the same characteristics (humidity, temperature, pressure) as its source region
what is a source region
the areas over which the air mass forms
arctic symbol, source region, warmth, and humidity
A, arctic basin/Siberia, bitter cold, dry
continental polar symbol, source region, warmth, and humidity
cP, interiors of Canada and Alaska, very cold, dry
continental tropical symbol, source region, warmth, and humidity
cT, southwest U.S./Mexico, warm, dry
maritime polar symbol, source region, warmth, and humidity
mP, north pacific ocean, humid, cold
maritime tropical symbol, source region, warmth, and humidity
mT, north Atlantic/ Gulf of Mexico, Caribbean Sea, warm, humid
What do all dry airmasses have in common
all form over land
what do all humid air masses have in common
they all from over water
what is the correlation between how humid and dry airmasses form?
the energy released and forming the air masses affects the content of the air mass. over water, there is more condensation and release of water vapor, and the opposite for land
lake-effect snow
as cold continental polar air moves over warm great lakes, air gains thermal energy and moisture. it cools as it rises due to convection and topographic land features, producing snow
How does an air mass’s characteristics change
when an air mass travels over areas of different characteristics than its source region, they may acquire some of those traits
thermometer
thermal expansion causes liquid to rise
electronic thermometer
electricity goes into probe, heat and resistance rises
mercury barometer
air presses down on mercury in vacuum tube
aneroid barometer
air squeezes and the chamber turns the lever
why is mercury used in barometer instead of water?
mercury is heavier and would not freeze or evaporate in extreme temperatures
anemometer
wind speed
wind vane
direction of wind
hygrometer (psychrometer)
device used to measure relative humidity
automated surface observing system (ASOS)
24-hour observation of weather conditions all over the U.S.
what is ASOS info used for
aviation, weather, forecasting, and research
Radiosonde
measures upper air temp pressure and humidity, transmits info on radiowaves
Rawinsonde
radiosonden + wind speed/direction
RADAR
Radio, Detection, and Ranging
Doppler effect
the change in pitch that occurs due to lengthening or shortening of sound or light waves
what happens when light/sound moves towards you?
pitch goes up
what happens when light/sound move away from you?
pitch goes down
what is the doppler radar used for
to measure direction of precipitation and wind speeds
what is a station model
a record of weather data for a particular site at a particular time
how are station models useful for meteorologists
fits large amount of data in small space
what is an isopleth
lines that connect points of equal or constant value
what do isobars show
lines of equal pressure
what do isotherms show
lines of equal temperature
what does it mean if isobars are close togeter
a large pressure difference over a small area, strong winds
how does the atmosphere behave
like a fluid
what is a digital forecast
making prediction about how variables will change overtime by applying physical principles and math to the atmospheric variables
analog forecast
based on a comparison of current weather patterns to similar ones from the past
what are digital and analog forecasts better for
digital for immediate forecast and analog for longer range
