The layer of the atmosphere in which the frictional force of the earth's surface exercises an appreciable influence on winds.

Electronic sensor used to record the number of lightning strokes within a predetermined range over a specified period of time.

A standard instrument approach procedure for fixed-wing aircraft in which an electronic glide slope is provided, such as ILS and PAR.

The designation of a vegetation complex described by dominant species, age, and form.

Any vehicle capable of supplying engine fuel to ground or airborne equipment.

The process in which teams of professional and peer counselors provide emotional and psychological support to incident personnel who are or have been involved in a critical (highly stressful) incident.

An atmospheric index used to indicate the potential for wildfire growth by measuring the stability and dryness of the air over a fire.

A vascular plant that has a usually continuous central internal stand of spongy tissue in the stem.

A number related to the potential number of firebrands to which a given area will be exposed during the rating day.

In smokejumping, rappelling, and paracargo operations, the individual responsible for selecting drop target and supervising all aspects of dropping smokejumpers, rappellers, or cargo.