Search Dog Handbook - Scott County Search and Rescue K9 Unit

SEARCH DOG HANDBOOK
Atmospheric stability is an important variable at all times, but the heat
release rate may be important on clear, cold nights or days, especially
with little wind.
Winds tend to push and bend or shear the column and restrict the total
possible plume rise. Strong winds may push the column nearly
horizontally until all of the heat is released and no more convective lift
occurs.
Deposition of Airborne Scent Material
Scent composition includes solid particles large enough to precipitate
and gases that may be absorbed into vegetation and other surfaces.
Airborne scent may deposit on the ground by: particle precipitation,
impaction and absorption at the ground surface, subsequent downward
turbulent flow into a sink, and rain or snow. All three mechanisms
deplete the plume of airborne scent.
But the resulting ground surface contamination, especially if
precipitation increases scent concentration close to the source, can aid
the search dog team trying to find the source.
Scent diffuses in water
The trained search dog can scent a human body or other chemicals
submerged in water once the molecules in question reach his nose. The
laws of physics hold here too. The difficulty lies in predicting what will
happen physically.
Scent diffusion through, and atmospheric release from, water is a
function of many variables including:
rate of fluid flow
direction of fluid flow
fluid composition and temperature
solubility of subject chemicals in fluid
ambient temperature
wind speed
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