List the Variable or "Greenhouse" Gases
- Carbon Dioxide (CO2)
- Methane (CH4)
- Ozone (O3)
- Water Vapor
List the Permanent or "Constant" Gases of the atmosphere
- Nitrogen 78%
- Oxygen 21%
- Argon 0.93%
99.9% of the gases (by volume) that comprise Earth's atmosphere is to be found in these two layers
Troposphere and Stratosphere
Describe the Ozonosphere
Found in the Stratosphere, 10-30 mi. above the surface. It absorbs ultraviolet light.
Describe the Ionosphere
40-250 mi. above surface. Isn't really a layer, but an electrified field of ions and free electrons. Absorbs cosmic, gamma and x-rays, and short wavelength ultraviolet radiation. "Aurora" lights are found in this region.
List the factors that determine Earth's Radiation Budget
- Time of Day
- Time of Year
- Atmospheric Thickness
- The Transparency of the Atmosphere
What percent of the world's water is in the atmosphere?
What is Orographic Rain?
Rain that is a product of condensation of water vapor in an air mass that rises over a mountain/hill.
What are the diff types of clouds based on altitude?
- STRATO: low-level, below 2000 m.
- ALTO: middle-level, 2000-6000 m.
- CIRRO: high-level, above 6000 m.
A Strato cloud is how high?
below 2000 meters
An Alto cloud is how high?
A Cirro cloud is how high?
above 6000 meters
What are the diff types of clouds based on shape?
- CIRRUS: highest and thin, feather-like
- STRATUS: horizontal, layered, uniform
- CUMULUS: vertical, sometimes look like cauliflowers
A high-level cloud that is thin and feather-like.
Horizontal, layered and uniform clouds are called:
Vertical clouds that sometimes look like cauliflowers are called:
List the 4 uplift mechanisms that lead to condensation and associated precipitation?
- convectional precipitation
- frontal precipitation
- cyclonic (convergence) precipitation
- orographic precipitation
What latitudinal zones receive higher annual rainfall, and why?
Equatorial zones b/c of high temps, high humidity and air instability.
What is Relative Humidity?
the ratio between the amount of water vapor in the air and the water vapor capacity of the air, at a given temp.
How is Relative Humidity expressed?
By % that says how close air is to saturation.
What is Adiabatic Cooling?
It's the change in temp within a gas b/c of expansion.
What is Adiabatic Heating?
It's the change in temp within a gas b/c of compression.
What is Evapotranspiration?
Combined water loss to the atmosphere from ground & water surfaces by evaporation, and from plants by transpiration.
A _______ is used to measure air pressure.
What are the 2 basic types of air pressure systems?
- Low (cyclone) - convergent, ascending air
- High (anticyclone) - divergent, descending air
Air pressure ______ with elevation.
What are the 2 Horizontal Variations of air pressure?
- Thermal (determined by temperature)
- Dynamic/Mechanical (due to motions of the atmosphere)
The horizontal movement of air in response to differences in pressure.
What are the basic wind patterns?
- Linear: pressure gradients & winds
- Circular: cyclones, anticyclones & winds
What are the Wind Modifiers?
- Friction: effective up to about 1000 m. from surface - reduces speed
- Coriolis Effect: deflection due to rotation
List the 3 factors that determine the Rate of Evaporation?
- temperature & available water
- relative humidity of surrounding air
Evaporation contributes ___% of atmospheric water.
Transpiration contributes ___% of atmospheric water.
_________________ accounts for virtually all the water vapor in the air.
The order of the Hydrologic Cycle:
Evapotranspiration > Water Vapors> Condensation> Cloud Formation> Precipitation> Evapotranspiration
Define Dew Point
the critical temp at which the air is fully saturated - the cooling of air to below its dew point temp that brings about condensation that must precede any precipitation.
The process that changes water vapor into a liquid form.
ice crystal formation on tree branches or airplane wings when supercooled droplets come in contact with the surface
forms in below freezing temperatures when water vapor changes directly to the frozen state through the sublimation process
rain bearing clouds
Which 3 conditions are necessary for precipitation to occur?
- moist air
- condensation nuclei
- uplift mechanism
What is an air mass?
a large body of air with similar temp and/or humidity.
Air masses are born in a _____ ______ where they acquire their temperature and moisture characteristics
Air Masses are classified by:
- Surface of Source Region - continental or maritime
- Latitudinal Extent of Source Region - Equatorial, Tropical, Polar or Cold Arctic
___________ is the main reason for the heavy rainfall in the forests of the Equatorial region.
Intertropical Convergence Zone (ITCZ)
List the diff types of Air Masses.
- continental arctic (cA)
- continental polar (cP)
- continental tropical (cT)
- maritime polar (mP)
- maritime tropical (mT)
- maritime arctic (mA)
What are fronts?
boundaries that separate air masses. where they meet but do not mix.
List the 4 types of fronts.
- occluded front
- warm front
- stationary front
- cold front
Describe a COLD FRONT.
Cold air replaces warm. Steeper than a warm front. Faster. More violent weather.