LESSON 1-water in the atmosphere
In the water cycle water vapor enters the atmosphere by___________, and leaves by___________.
in the water cycle water vapor enters the atmosphere by evaporation, and leaves by condensation.
Define Dew point.
The temperature a which condensation begins is called the dew point.
What are the common types of precipitation?
common types of precipitation include rain sleet freezing rain snow and hail
what are the major air masses?
four major types of air masses influence the weather in North America: maritime tropical, continental tropical, maritime polar, and continental polar.
how do meteorologists predict the weather?
they use maps charts computers and other technology to analyze weather data and to prepare weather forecasts.
Define relative humidity.
relative humidity is the percentage of water vapor that’s actually in the air compared to the maximum amount of water vapor the air can hold.
How do clouds form?
Clouds form when water vapor in the air condenses to form liquid water or ice crystals.
what is precipitation
precipitation is any form of water that falls from clouds and reaches earths surface.
Define tropical, polar, maritime, and continental.
tropical or warm air masses form in the tropics and have low air pressure.Polar or cold air masses form north of 50 degrees north latitude and 50 degrees south latitude.
Maritime air masses form over oceans.continental air masses form over land
Define isobar
isobars are lines joining places on a weather map that have the same air pressure.
Define condensation
Condensation is the process by which water vapor becomes liquid water
What are the three main types of clouds? How are they classified?
Scientists classify clouds into three main types based on their shape: cirrus, cumulus, and stratus. Clouds are further classified by their altitude.
How is rain measured
rain is measured with a rain gauge. A rain gauge is an open ended tube that collects rain.
What are the main types of fronts
Colliding air masses can form four types of fronts: cold fronts, warm fronts, stationary fronts, and occluded fronts.
Define isotherms
isotherms are lines on a weather map connecting places with the same temperature
How are humidity and relative humidity different?
humidity is a measure of the amount of water vapor in the air, while relative humidity is the percentage of water vapor that is actually in the air compared to the maximum amount of water vapor the air can hold.
Define cirrus, cumulus, and stratus clouds.
cirrus clouds are wispy and feathery. They form at high altitudes, usually above 6km. They indicate fair weather
cumulus clouds look like cotton. They form 2km above the ground but may extend up to 18km. Short cloud indicate fair weather but towering clouds often produce thunderstorms.
stratus clouds form in flat layers and are usually a dull gray color. As they thicken they may produce drizzle rain or snow
What factors determine if precipitation falls as freezing rain or as sleet?
the temperature
Define front
a front is the boundary where the air masses meet.
What is a weather map?
a map that shows what the weather is like in different places at a certain time.
How is relative humidity measured?
Relative humidity can be measured with an instrument called a Psychrometer, which has two thermometers, a wet-bulb thermometer and a dry-bulb thermometer.
Define fog.
Clouds that form near the ground are called fog. Fog can form when the ground cools at night after a humid day
What is the name for raindrops that freeze as they fall through the air
sleet
How are air masses classified?
By temperature and humidity.
What can we learn from a weather map?
where the fronts are, areas of high and low pressure, types of precipitation, and temperatures