Chapter 19 - Weather Flashcards
What do meteorologists use to measure temperature?
Thermometers
What is the scientific study of the atmosphere?
Meteorology
How are temperatures indicated?
In degrees Fahrenheit or degrees Celcius
What is air pressure measured in units of?
Lb/in2 or psi- or N/m2 PASCAL
What is the instrument used to measure air pressure?
Barometer
What is the direction from which the wind is coming?
Wind direction
Where do vanes point?
Into the wind, not toward the direction the wind is going
What are wind speeds reported in?
Knots
What do they use to measure wind speed?
Anemometer
What amount of wind can make air seem cooler?
Any amount of air
What is precipitation measured in?
Millimeters or inches of liquid water
What do we use to measure precipitation?
Rain gauges
Can warmer or cooler air hold more water vapor?
Warmer air
How is the fraction of relative humidity expressed?
As a percent
What is humidity measured with?
Hygrometers
How is wind created?
Air moves from higher to lower pressure
What deflects a wind perpendicular to its path over the earth’s surface?
The Coriolis effect
Is the Coriolis effect stronger farther away or closer to the equator?
Farther away
How do cyclones turn in the Northern Hemisphere?
Counter clockwise
What affects wind?
The Coriolis effect
What do the prevailing westerlies give the US?
It’s weather
Where are most of the winds in the US from?
The west and southwest
Where are the horse latitudes?
At 30 degrees latitude either north or south
Does land or water absorb energy from the sun more readily?
Land
How do the bar-headed geese migrate?
They ride on jet streams
What is the dew point?
100% relative humidity
What is a cloud?
A mass of extremely tiny liquid water droplets or ice crystals in the air
Some cloud droplets remain liquid even down to temperatures of what?
-40 degrees
Stratus
Thin layers or sheets
Cumulus
Piles or billows
Cirrus
High, wispy curls
Strato
Less than 1 mile high
Alto
1-4 miles high
Cirro
4-12 miles high
When stratus-like clouds form at ground level we call them what?
Fog
What precipitation do cirro clouds make?
None
What precips do alto clouds give?
From light to wisps of rain or snow
Precips of strato
Light to heavy rain
Precips of stratus
Drizzle to steady rain or snow
Precips of cirrus
None
Precips of cumulus
Infrequent light rain or snow, or fair weather
What kind of rain is acidic?
All rain is acidic
What is the process of coalescence?
When larger clouds droplets can’t be held up by the air molecules anymore, fall slowly, join with other droplets, and their sizes grow rapidly
What are three types of solid precipitation?
Sleet, hail, and snow
Is dew precipitation?
NO
When a cool surface causes the temperature to drop forms what?
Dew
What forms frost?
Water vapor deposition
