GRG (10/29) Unstable Air, Dew/Frost, Fogs

Heating

Instability is enhanced by radiational __________ of Earth’s surface.

Below

Instability is enhanced by heating an air mass from ________.

Topographic Lift

Air must be forced up dynamically to pass over mountains/fronts, enhancing instability.

Upward Motion

Instability is enhanced by _________ _________ with surface air convergence.

Cooling, Nocturnal

Instability is enhanced by radiational ____________ from ___________ thunderstorm cloudtops.

Dew

Water that has condensed onto objects near the ground when the temperature of these objects has cooled below the dew point temperature of the surrounding air.

Frozen Dew

When dew freezes, it becomes __________.

Frost

A covering of ice crystals produced by deposition on exposed surfaces when the air temperature falls below the freezing point and the temperature of the exposed object falls below the surrounding air's dew point temperature.

Frost, Snow

Formed by deposition (2).

Saturation & Condensation Nuclei

Conditions for Cloud Formation

Cloud Seeding

Man-made Condensation Nuclei

Fog

Clouds on The Ground

Radiation Fog

The Earth's surface radiates heat, cooling until it reaches the dew point. Needs a little wind motion to form (2-4mph).

Advection Fog

Known for “rolling” on the surface of water that is cold enough to reach the dew point temperature. Involves the process of upwelling.

Upwelling

Cold, nutrient-rich water rises to the surface along the coast.

Evaporation/Mixing Fog

When you breathe, the air is too cold to let the moisture from your breath exist as water vapor.

Upslope Fog

Clouds that you are experiencing at a higher elevation as they pass through mountainous regions.