The Atmosphere Flashcards
Atmosphere
the blanket of gases that surround the Earth
Troposphere
layer of the atmosphere closest to Earth surface, where we live
Atmospheric Gases
78% Nitrogen
21% Oxygen
1% Other gases (argon, carbon dioxide and water vapor)
Condensation Nuclei
Solids in the atmosphere such as dust and salt that combine with water vapor to create clouds
Humidity
amount of hydrogen in the air
constantly changing due to temp, altitude, ground features, etc.
Relative Humidity
comparison between how much water vapor is currently in the air and how much it can hold
Warm air holds more
humidity
High temp-
Max saturation-
At 100% relative humidity, current temperature is
high max saturation
100% relative humidity
equal to dew point
Convection currents cause
weather
Lifted Condensation Level (LCL)
height where condensation occurs
Cirrus Clouds
thin, feathery clouds that form at high altitudes
Cumulus
white, puffy clouds usually on fair-weather days
Stratus
low-lying layered sheets of clouds often on drizzly days
Nimbus
low-altitude, gray rain clouds
Coalescence
when clouds droplets collide and join together, eventually getting to heavy and falling (precipitation)
Sleet
pellets formed when raindrops fall through freezing air
Hail
layered lumps of ice created in cumulonimbus clouds, when droplets in the cloud constantly melt and refreeze
Earths temperatures vary due to three things
geographic position, altitude, and surface material
Geographic position
the Earth’s surface unevenly heated by the Sun because the Earth is curved and sits on its axis
Surface Material
water has a higher specific heat than land
Air Pressure
the force exerted on Earth’s surface due to the weight of the air, varies with elevation
High-Pressure Systems
sinking air reaches the surface and spreads from the center, spins clockwise, fair weather
Low-Pressure Systems
air rising and other air flows towards the center to replace it, counterclockwise, clouds and precipitation
Air Mass
large body of air that takes on the characteristics of the land or water under it (the source region)