Aos 100 Test 1 Key Terms

Front 1

Pressure

Back 1

The force exerted on a given area (atmospheric pressure and density always decrease as altitude increases)

Front 2

Temperature

Back 2

A measure of the average kinetic energy of a substance (does not always decrease as altitude increases…it generally does in the troposphere which is closest to earth, but then temp increases with altitude in the stratosphere, decreases in the mesosphere, and increases with increasing altitude in the thermosphere(highest))

Front 3

• Electromagnetic radiation:

Back 3

Energy in the form of waves that are not composed of matter.

Front 4

• Solar radiation:

Back 4

Moves through empty space from the sun to the Earth and is the original energy source for our weather and climate. Sometimes referred to as shortwave radiation because it has a short wavelength. Solar radiation includes ultraviolet, visible, and near-infrared radiation.

Front 5

• Terrestrial radiation:

Back 5

Also known as longwave radiation, is emitted by the Earth and is less energetic than solar radiation and is characterized by much longer wavelengths.

Front 6

• Kinetic energy:

Back 6

The work that a body can do by virtue of its motion. KE of a moving object is directly related to its mass

Front 7

• Potential energy:

Back 7

The work that a body can do as a result of its relative position. It represents stored energy that can be converted to other forms of energy, such as kinetic

Front 8

• Heat energy:

Back 8

Heat is energy produced by the random motions of molecules and atoms; it is the total kinetic energy of a substance

Front 9

• Conduction

Back 9

(Requires Touching): The process of heat transfer from molecule to molecule; energy transfer by conduction requires contact. Heat is transferred from the warmer object to the cooler one. The amount of energy transferred by conduction depends on the temperature difference between the two objects and their thermal conductivity. The ability of a substance to conduct heat by molecular motions is defined by its thermal conductivity. Water is a good conductor of heat while air is not. Wood and metal example: Metal is much more conductive and feels colder when you touch it in a cool environment because it is good at taking the heat from your hand and that makes your hand feel cold. Wood is a bad conductor and does not steal much heat and thus doesn’t feel as cold. (Because air is a poor conductor, conduction is not an efficient mechanism for transferring energy in the atmosphere on a global scale)

Front 10

• Convection

Back 10

(Hot Air Rises): The process of transferring heat vertically. Does not require touching. In the atmosphere, the rate of energy transfer by convection depends on how hot the rising air parcel is and the vertical temperature pattern of the surrounding atmosphere. Convection is an inefficient mode of heat transfer in polar regions, where the surface air is in contact with a surface that is often cooler than the air above it.

Front 11

• Advection

Back 11

(Horizontal Movement): The horizontal transport of energy in the atmosphere. Warm air advection occurs when warm air replaces cooler air. In winter snowstorms, warm air advection moves warm air poleward while cold air advection brings cold air to the tropical regions. Advection is an important process throughout the troposphere, especially close to the Earth’s surface.

Front 12

• Latent heating

Back 12

(Changing the Phase of Water): The heat absorbed or released per unit mass when water (in any of its 3 phases) changes phase. Latent heat of melting is the amount of energy absorbed by water to change 1 gram of ice into liquid water. Latent heat of fusion is the amount of energy released into the environment when water freezes. Latent heat of vaporization is the amount of heat required to evaporate 1 gram of liquid water. Latent heat of condensation is the amount of energy released when water vapor condenses to a liquid form. Latent heat of deposition is the amount of energy released when water vapor changes directly into ice. Latent heat of sublimation is the amount of heat required to change ice directly into water vapor without melting. Latent heat of sublimation = latent heat of deposition. Evaporation is a cooling process that removes energy from the physical environment. Condensation is the opposite of evaporation and is a heating process that supplies energy to the environment. The phase changes of evaporation and condensation have by far the largest latent heats of the common phase changes of water.

Front 13

• Radiation

Back 13

(Exchanging Energy with Space): First law is that all objects with a temperature above absolute zero emit radiation

Front 14

• Specific heat:

Back 14

amount of energy required to increase the temperature of 1 gram of that substance 1 degree Celsius…the specific heat of water is high, meaning it takes a lot of energy to warm or cool it…takes 4 times as much energy to warm one gram of water one degree Celsius as it does to warm one gram of air one degree Celsius

Front 15

• Atmospheric gases:

Back 15

In order of highest percentage by volume to lowest: Nitrogen, oxygen, argon, carbon dioxide, methane, ozone, chlorofluorocarbons (CFCs), water vapor (highly variable so it might not actually be at the end of the list…changes too much to rank)

Front 16

• Sensible heat:

Back 16

The transfer of energy by warm air without a change of phase of water. Sensible heat and latent heat combine to provide 102 Watts of heat to the atmosphere (that is how much the atmosphere loses, so we do not observe any change)

Front 17

• Aerosol:

Back 17

Liquid and solid particles present in the atmosphere. Examples include smoke, salt, ash, smog, and dust. The amount and type of aerosol can influence the climate of a region by modifying the amount of solar energy that reaches the surface. Aerosols are needed to form most clouds.

Front 18

• Albedo:

Back 18

The albedo of an object describes the percentage of light that it reflects. The higher the albedo, the whiter the object. Example: Freshly fallen snow has an albedo of 90%, whereas green grass has an albedo of 25%.

Front 19

• Temperature Inversion:

Back 19

A vertical layer of the atmosphere in which temperature increases with height

Front 20

• Temperature Lag:

Back 20

The time delay between a cause and an effect. For example, typically the coldest winter temperatures lag several weeks behind the shortest day of the year, partly due to the thermal properties of the Earth and oceans.

Front 21

• Temperature Range:

Back 21

The difference between the maximum and minimum temperatures at a location.

Front 22

• Wind Chill:

Back 22

a measure of the increased loss of heat by living organisms due to the movement of the air

Front 23

• Relative humidity:

Back 23

The ratio of the observed vapor pressure of the air to the saturation vapor pressure, expressed as a percentage. Relative humidity indicates how close the air is to saturation (100% relative humidity)

Front 24

• Dew point:

Back 24

The temperature to which air must be cooled at constant pressure and constant water vapor content to become saturated

Front 25

• Vapor pressure:

Back 25

The pressure exerted by water molecules in a given volume of the atmosphere. It is a measure of the contribution of water vapor to the total pressure.

Front 26

• Saturation vapor pressure:

Back 26

The vapor pressure at which the number of molecules leaving a liquid or ice surface equals the number of molecules entering the liquid or ice. It is a function of temperature only.

Front 27

• Solstice:

Back 27

The sun is highest in the mid-latitude summer sky. Northern hemisphere summer solstice occurs around June 21. Latitudes south of 66.5 degrees south (Antarctic Circle) remain in complete darkness. During the NH winter solstice (December 21), latitudes north of 66.5 degrees north (Arctic Circle) remain in complete darkness.

Front 28

• Equinox:

Back 28

occur when the sun’s rays strike the equator at noon at an angle of 90 degrees. In the NH, spring equinox is march 21 or 22 and the fall equinox is September 22 or 23. All locations on earth experience 12 hours of daylight on equinoxes.

Front 29

risng parcel of air

Back 29

always expands (decreasing air pressure) and always cools (loss of kinetic energy)

Front 30

descending parcel of air

Back 30

always warms (gains kinetic energy)

Front 31

how to change dew point

Back 31

increase dew point by adding water vapor to the air. decrease dew point by removing water vapor from the air.

Front 32

how to change relative humidity

Back 32

to increase RH: add water vapor and/or cool the air. to decrease RH: remove water vapor and/or warm the air

Front 33

how to change vapor pressure

Back 33

increase VP by increasing temp, increases by increasing the number of water vapor molecules in a given volume of air. cooling the air will decrease VP,

Front 34

how to change saturation vapor pressure

Back 34

increases rapidly as temperature increases...it is ONLY affected by temp

Front 35

radiation fog

Back 35

forms in the same way dew does. on clear, long nights the ground cools by radiation and the air above the ground cools by conduction and radiation. as the temp of the air drops, rel humidity increases and a radiation fog may form

Front 36

advection fog

Back 36

when warm air is advected (blown horizontally) over a cold surface, the air near the ground cools because of energy exchanges with the surface. The rel humidity increases and an advection fog may form

Front 37

evaporation fog

Back 37

they occur in the vivinity of warm fronts. they form when water evaporates from rain that falls from warmer air above the ground into cold air near the surface.

Front 38

upslope fog

Back 38

Air must rise over a mountain barrier. as the air rises, it expands and cools and the rel humidity rises. if the air becomes saturated, an upslope fog forms

Front 39

orographic lifting

Back 39

Air is lifted as it moves against a mountain range. The air cannot go through the mountain, and so it flows over the mountain

Front 40

frontal lifting

Back 40

As fronts move, frontal lifting occurs when less dense warm air is forced to rise over the cooler, denser air. frontal lifting is common in winter

Front 41

convection (lifting mechanism)

Back 41

convection is an important lifting mechanism in the summer. solar energy passes through the atmosphere and heats the surface. The air near the surface warms, becomes less dense than the air around it, and rises.

Front 42

convergence (lifting mechanism)

Back 42

occurs when air near the surface flows together from different directions. when the air near the ground converges, or is squeezed together, it causes upward motion.

Front 43

collision-coalescence

Back 43

aids in the formation of warm clouds. cloud particles have to bump into each other and merge together, or coalesce.

Front 44

accretion

Back 44

the growth of an ice particle by collision and coalescence of supercooled water droplets

Front 45

aggregation

Back 45

the process of ice-crystal growth by collision and adherence of ice crystals

Front 46

Bergeron-Wegener Process

Back 46

The process by which ice crystals grow more rapidly than water droplets in a cold cloud because of differences in the saturation vapor pressures of ice and liquid water at the same subfreezing temperatures