Fog!                                               10/6

    1.  Clarify adiabatic rates.
              An adiabatic process is one in which a physical system (cloud) does not exchange energy with its environment via heat flow.  We
                 are particularly interested in the dry adiabatic rate, i.e., the rate (temperature change per unit distance) at which the temperature
                 of a rising unsaturated air parcel drops or a sinking unsaturated air parcel rises because of work done on or by the environment,
                 and the moist adiabatic rate (temperature change per unit distance) at which the temperature of a rising saturated air parcel drops
                 or a sinking saturated air parcel rises because of work done on or by the environment.  These two rates differ because latent heat
                 is released as condensation occurs (cloud forms) in a rising saturated parcel and latent heat is absorbed as evaporation occurs
                 (cloud dissipates) in a sinking saturated parcel.  Latent heat plays no role in the adiabatic rate of a dry parcel.

    2.  Review the calculation of relative humidity.
              Relative humidity is defined as AVP/SVP, the ratio of the actual vapor pressure (AVP) to the saturation vapor pressure (SVP). 
                 The saturation vapor pressure of air depends only upon its temperature and can be looked up in tables (e.g., Ahrens, Table 1,
                 p. 98) if the temperature is known.  The actual vapor pressure, depends on and is directly proportional to the moisture content of
                 the atmosphere.  It can be determined from the dew point or wet bulb temperature (combined with the dry bulb temperature) if
                 either of those are known.

    3.  Review cloud classifications, especially their association with different types of weather.
               (This will be done in detail in the next class lecture.)

    4.  What is the difference between frozen dew and frost.
              Frozen dew forms when atmospheric water vapor condenses as dew (water), then chills and freezes to become ice.  Frost forms
                 when, at a temperature below freezing, water vapor is directly deposited on a surface as ice.  It never passes through the liquid
                 (water) stage.  Frost is deposited in intricate crystal patterns, quite different in appearance from frozen dew.

    5.  Stability graph:  the relationship between slope and stability.
              (This will be done in detail in today's lecture.)