Saturated Adiabatic Lapse Rate

What occurs in a saturated ascending air parcel?

condensation of water vapor turns into cloud droplets and is accompanied by the release of latent heat

What does release of latent heat mean?

air parcel cools at a rate called the “saturated adiabatic or moist adiabatic lapse rate”

Moist (or saturated) adiabatic lapse rate:

rate at which temperature of a saturated parcel that is rising adiabatically falls with respect to height

What happens to the air parcel as it rises?

parcel cools because of adiabatic expansion and at the same time it warms because of latent heat release

Which tends to be great: the saturated adiabatic lapse rate or the dry adiabatic lapse rate?

the dry adiabatic lapse rate

Why does saturated adiabatic lapse rate have a variable value?

because it depends on temperature

Why does the saturated adiabatic process depend on temperature?

warmer saturated air contains more water vapor, so it experiences more latent heat release when there’s condensation during rising motion

When any air encounters a mountain what occurs?

the air is forced upward

In ascent, dry adiabatic is followed by

moist adiabatic

In Descent dry adiabatic

air parcel has precipitated all the condensate as it was rising

In descent, moist adiabatic

parcel’s condensate is evaporating and moistens the parcel as its temperature rises adiabatically

What occurs in the sinking air parcel of saturated adiabatic descent?

temperature lapse rate of a saturated air parcel (RH = 100%) where evaporation of water is occurring

Evaporating cooling in sinking parcel offsets:

warming due to adiabatic compression

What happens in warmer conditions of saturated adiabatic lapse rate?

more droplet evaporation is possible and so the latent heat absorption and resulting cooling of the parcel is more