The Atmosphere Flashcards
Electromagnetic Energy
Energy that travels in waves, including visible light, UV, infrared, and others; key for heat transfer from the Sun
Wavelengths
The distance between two successive wave crests; shorter wavelengths (like UV) carry more energy than longer ones (like infrared)
Albedo
The percentage of incoming solar radiation reflected by a surface. High albedo = more reflection (e.g., ice, snow)
Conduction
The transfer of heat through direct contact between molecules, significant near Earth’s surface
Convection
The vertical transfer of heat through the movement of a fluid (air or water), driving atmospheric circulation
Radiation
The transfer of energy via electromagnetic waves; how the Sun’s energy reaches Earth
Latent Heat
Energy absorbed or released during a phase change (e.g., evaporation absorbs heat, condensation releases heat) without changing temperature
Phase Change
The transition between solid, liquid, and gas states, involving absorption or release of latent heat
Latitude
Determines the angle and intensity of solar radiation; lower latitudes (near the equator) are warmer
Distribution of Land and Water
Land heats and cools faster than water, leading to more extreme temperatures inland and moderate temperatures near coasts
Specific Heat
The amount of energy needed to raise the temperature of a substance; water has a high specific heat compared to land
Elevation
Higher elevations are cooler due to decreasing air pressure and temperature with heigh
Humidity
The amoount of water vapor in the air
Relative Humidity
The percentage of the maximum water vapor the air can hold at a given temperature
Dew Point
The temperature at which air becomes saturated and condensation begins (forming dew, fog, or clouds)
Air Pressure
The force exerted by the weight of the atmosphere; measured with barometers, decreases with height
High Pressure (Anticyclone)
A system where air sinks, diverges at the surface, and creates clear, stable weather
Low Pressure (Cyclone)
A system where air rises, converges at the surface, leading to clouds and precipitation
Difference Between Cyclone and Anticyclone
Cyclones: low pressure, air rises, cloudy/stormy; Anticyclone: high pressure, air sinks, clear skies
Pressure Gradient Force
The force that causes air to move from high to low pressure; stronger gradients = faster winds
Wind
The horizontal movement of air from high to low pressure areas; named for the direction it comes from
Stable Air
Air that resists vertical movement; often associated with clear skies
Unstable Air
Air that rises freely; often leads to cloud formation and storms
Orographic Uplift
When air is forced to rise over a mountain or high terrain, cooling and often leading to precipitation
Convergence
When air flows together at the surface and rises, often leading to cloud formation and precipitation
Coriolis Effect
The deflection of moving air (and water) due to Earth’s rotation: to the right in the Northern Hemisphere, to the left in the Southern Hemisphere
Air Mass
A large body of air with uniform temperature and humidity characteristics
Source Region
The geographic area where an air mass acquires its temperature and moisture characteristics (e.g., over oceans, deserts)
Types of Air Masses
cP (continental polar): cold, dry; mP (maritime polar): cool, moist; cT (continental tropical): hot, dry; mT (maritime tropical): warm, moist; A (Arctic): very cold, dry
Weather Fronts
Boundaries between different air masses where weather changes occur
Cold Front
Boundary where cold air advances and forces warm air upward, leading to thunderstorms and cooler temperatures
Warm Front
Boundary where warm air advances over cold air, producing steady rain or snow and gradual warming
Stationary Front
A front that isn’t moving significantly; often causes prolonged periods of clouds and precipitation
Norwegian (Cyclone) Model
A model describing mid-latitude cyclones: begins with a stationary front; cyclongenesis (storm development) occurs; cold and warm fronts form; storm matures and occludes (cold front catches warm front); system eventually dissipates
Rain
Liquid water droplets that fall from clouds when temperatures are above freezing
Snow
Frozen water crystals falling when temperatures are below freezing
Sleet
Frozen raindrops; rain falls through a layer of freezing air near the ground
Freezing Rain (Glaze)
Rain that freezes upon contact with cold surfaces, forming a coating ice
Hail
Balls or lumps of ice formed in strong thunderstorms with intense updrafts
