Meteorological range: Difference between revisions
From Glossary of Meteorology
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<div class="definition"><div class="short_definition">(''Also called'' standard visibility, standard visual range.) An empirically consistent measure of the [[visual range]] of a [[target]]; a concept developed to eliminate from consideration the [[threshold contrast]] and [[adaptation luminance]], both of which vary from [[observer]] to observer.</div><br/> <div class="paragraph">The meteorological range is the distance ''V''′ in the black target form of the [[visual-range formula]], <div class="display-formula"><blockquote>[[File:ams2001glos-Me10.gif|link=|center|ams2001glos-Me10]]</blockquote></div> when ε, the threshold contrast, is set equal to 0.02. Thus, ''V''′ is a function only of the [[extinction coefficient]] σ of the [[atmosphere]] at the time and place in question.</div><br/> </div> | <div class="definition"><div class="short_definition">(''Also called'' standard visibility, standard visual range.) An empirically consistent measure of the [[visual range]] of a [[target]]; a concept developed to eliminate from consideration the [[threshold contrast]] and [[adaptation luminance]], both of which vary from [[observer]] to observer.</div><br/> <div class="paragraph">The meteorological range is the distance ''V''′ in the black target form of the [[visual-range formula]], <div class="display-formula"><blockquote>[[File:ams2001glos-Me10.gif|link=|center|ams2001glos-Me10]]</blockquote></div> when ε, the threshold contrast, is set equal to 0.02. Thus, ''V''′ is a function only of the [[extinction coefficient|extinction coefficient]] σ of the [[atmosphere]] at the time and place in question.</div><br/> </div> | ||
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Revision as of 16:25, 25 April 2012
meteorological range
(Also called standard visibility, standard visual range.) An empirically consistent measure of the visual range of a target; a concept developed to eliminate from consideration the threshold contrast and adaptation luminance, both of which vary from observer to observer.
The meteorological range is the distance V′ in the black target form of the visual-range formula, when ε, the threshold contrast, is set equal to 0.02. Thus, V′ is a function only of the extinction coefficient σ of the atmosphere at the time and place in question.
