Glossary U

Unconscious
interruption of awareness of oneself and one's surroundings, lack of the ability to notice or respond to stimuli in the environment. A person may become unconscious due to oxygen deprivation, shock, or injury.

Updrift (ocean)
The direction opposite that of the predominant movement of sediment along the shore. The side of a groin, jetty or other structure where sand accumulates.

Upland
A general term for land or ground that is higher than the floodplain.

Uprush (ocean)
The landward flow of water up onto the beach that occurs when a wave breaks.

Upstream
The direction toward a river's source; opposite to the rivers' flow.

UV Degradation
A breaking down of material due to the sun's harsh ultraviolet rays. UV degradation can be a potential problem with tent flies exposed to the sun for extended periods.