Weather Unit – Test, Friday Jan. 16th
Vocabulary – Put a check mark in front of each word that we cover in class
Climate – a description of the usual temperature, precipitation, and seasons of an area
Polar – cold climates; the area surrounding the Earth’s poles
Moderate/Temperate – medium climates
Tropical – hot climates; the area surrounding the Earth’s equator
Humid – wet
Arid – dry
Weather – a description of the atmosphere in a particular place at a particular time. Weather is a
measure of temperature, precipitation, humidity, wind, and air pressure.
Atmosphere – the layers of gases which surround the Earth; Weather occurs in the lowest layer of the
Earth’s atmosphere.
Air mass – a huge body of air which has similar temperature, pressure, and humidity throughout. Air
masses move and create new weather
Thermometer – an instrument used to measure temperature
Barometer – an instrument used to measure pressure
Anemometer – an instrument used to measure wind speed
Clouds – water vapor in the Earth’s atmosphere which collects on bits of dust. Clouds are visible
because the water vapor condenses or freezes as it rises into the colder heights of the atmosphere
Cirrus – wispy, feathery clouds
Cumulus – puffy, heaps of clouds
Stratus – spread out clouds which cover the whole sky
Alto – high in the sky
Nimbus – storm cloud
Front – the boundary between two air masses; weather changes at fronts
Local winds – winds that blow over short distances
Global winds – winds that blow steadily in specific directions over long distances
Doldrums – the area near the equator which has little to no wind
Horse latitudes – calm air at 30◦ N and S latitude
Trade winds – winds which blow from the Northeast to the equator in the Northern Hemisphere and
southeast to the equator in the Southern Hemisphere
Prevailing westerlies – winds which blow west to east across the midlatitudes of the Earth, including
the United States
Polar easterlies – winds which blow east to west across the polar regions of the Earth
Jet stream – a steady wind which blows from west to east about 6 miles above the Earth’s surface
Essential questions –
What is the difference between climate and weather?
How are clouds named?
What global winds affect our area?
How does air pressure affect the weather?