Transcript CJ235-01 Unit 2 Canines in Criminal Justice Factors that Affect

CJ235-01
Unit 2
Canines in Criminal Justice
Factors that Affect Scent
Factors that Affect Scent
• We will be speaking in terms of
environmental factors that affect scent
mostly outdoors.
Factors that Affect Scent
• We will be speaking in terms of
environmental factors that affect scent
mostly outdoors.
• These factors actually must be considered
whether searching for a person or a
substance such as an explosive or
narcotics.
Factors that Affect Scent
• Since we will be discussing searching or
tracking outdoors for people in the next
unit, we will focus on those
environmental factors that occur
outdoors.
Factors that Affect Scent
• Since we will be discussing searching or
tracking outdoors for people in the next
unit, we will focus on those
environmental factors that occur
outdoors.
• These same facts apply whether
searching for a fleeing criminal or a lost
child.
Air Currents
• Do you always know when the wind
blowing?
Air Currents
• Do you always know when the wind
blowing?
• Syrotuck (2000) tells us of
micrometeorology and how temperatures
can vary from just a few inches off the
ground to a few feet and so can the
slightest air current.
Air Currents
• We see that any obstruction can affect
wind flow and therefore affect scent.
Turbulence
WIND
Reproduced with Permission from Barkleigh.com © 2000
Syrotuck, W. G. (2000). Scent and the scenting dog. Mechanicsburg, PA: Barkleigh .
Air Currents
• Natural Terrain can have an even more
profound affect on a person’s scent.
Turbulence
Obstruction
Reproduced with Permission from Barkleigh.com © 2000
Syrotuck, W. G. (2000). Scent and the scenting dog. Mechanicsburg, PA: Barkleigh.
Dead Area
Air Currents
• This diagram illustrates how obstruction
can deflect scent in different directions.
Victim
Scent Deflected
Reproduced with Permission from Barkleigh.com © 2000
Syrotuck, W. G. (2000). Scent and the scenting dog. Mechanicsburg, PA: Barkleigh.
Air Currents
• With no terrain, the velocity of the air
current determines the dispersion.
Slow Winds
Victim
Scent Cones
WIND DIRECTION
Victim
High Winds
Diagram by Jonathan Dorriety
Air Currents/Terrain
• Scent can often be carried with the path
of least resistance if obstructions create
one.
Dense Obstruction
Victim
Reproduced with Permission from Barkleigh.com © 2000
Syrotuck, W. G. (2000). Scent and the scenting dog. Mechanicsburg, PA: Barkleigh.
Terrain
• The lay of the land can also affect where
scent flows and pools if wind is not a
factor.
Downward Slope
Pooling Scent
Reproduced with Permission from Barkleigh.com © 2000
Syrotuck, W. G. (2000). Scent and the scenting dog. Mechanicsburg, PA: Barkleigh.
Temperature
• How does temperature affect scent?
Temperature
• How does temperature affect scent?
• Cool air on hilltops warms in the
morning and is replaced by cool air
flowing uphill.
Reproduced with Permission from Barkleigh.com © 2000
Syrotuck, W. G. (2000). Scent and the scenting dog. Mechanicsburg, PA: Barkleigh.
Temperature
• How does temperature affect scent?
• As the day grows warm cool air will
descend downhill.
Crevice
Reproduced with Permission from Barkleigh.com © 2000
Syrotuck, W. G. (2000). Scent and the scenting dog. Mechanicsburg, PA: Barkleigh.
Temperature
• A person hiding outside in cool weather is
more easily found than a person hiding in
warm weather. Why?
Temperature
• A person hiding outside in cool weather is
more easily found than a person hiding in
warm weather. Why?
• Our warm bodies will simply produce
more scent when our surroundings are
cooler, just as a deceased person whose
body has lost all heat will be more
difficult to locate in cool weather.
Humidity
• How do you think humidity plays into the
scent picture?
Humidity
• How do you think humidity plays into the
scent picture?
• Moist air (especially cool air) makes it
easier on a dog. Bacteria and skin rafts
flourish better with moisture in the air.
Humidity
• How do you think humidity plays into the
scent picture?
• Moist air (especially cool air) makes it
easier on a dog. Bacteria and skin rafts
flourish better with moisture in the air.
• Dogs also can work for longer periods
without rest in cool, moist environments.
Summary
• Wind is a major factor on scent in an
outdoor environment. They can be
indoors as well, but generally not to the
same extreme.
Summary
• Wind is a major factor on scent in an
outdoor environment. They can be
indoors as well, but generally not to the
same extreme.
• Obstacles and the lay of the land will also
have a strong influence on scent.
Summary
• Wind is a major factor on scent in an
outdoor environment. They can be
indoors as well, but generally not to the
same extreme.
• Obstacles and the lay of the land will also
have a strong influence on scent.
• Temperature and humidity in various
combinations can be good or bad.
Questions or Discussion?