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TYPES OF COLD DAMAGE AND TYPES OF FREEZES
 

 

TWO TYPES OF COLD TEMPERATURE INJURY

Chilling Injury - damage or death due to cold, yet above freezing temperatures (32 to 45 oF).

Freeze Injury - damage or death due to temperatures below freezing (below about 28 oF).
 
 
 

TWO TYPES OF FREEZES BASED ON HOW THEY OCCUR

1) Radiational Freeze or Frost - temperature drops due to radiational cooling which results
                                                  in a temperature inversion; occurs on calm, clear nights.
                                                  (see diagram on next page)

  • radiational cooling - loss of heat by long wavelength infrared (IR) radiation.
  • temperature inversion - a warm air mass above a cold air mass.
  • dew point - the temperature at which air reaches 100% relative humidity. 

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    2 Types of Radiational Freezes

    a) white frost - occurs when the temperature drops below both the current dew point (dew forms)
                           and below freezing (dew freezes).

    b) black frost - occurs when the temperature drops below freezing, but remains above 
                            the current dew point.
     

2) Advective Freeze - temperature drops due to the invasion of a cold air mass or convection current.