RELATIVE HUMIDITY ERRORS RESULTING FROM AMBIGUOUS DEW-POINT HYGROMETER READINGS,

Abstract

The instruments currently used in weather stations for measuring humidity work very well at high temperature, but become increasingly inaccurate at temperatures below freezing because of the small amount of water vapor in the air. Consideration is being given to using a dewpoint hygrometer, an instrument which is able to deect small quantities of moisture with great accuracy. Unfortunately, over a considerable temperature range below 32 F the instrument may record either the dew point or the frost point of the air. This study was carried out to determine whether this ambiguity would lead to significant errors in the computed relative humidity. It was found that the effect was large enough to adversely affect the accuracy of current techniques for forecasting clouds, fog, contrails, and other moisture-dependent phenomena. Suggestions are given for designing the instrument to eliminate the problem. (Author)

Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1963
Accession Number
AD0420921

Entities

People

  • H. S. Appleman

Tags

DTIC Thesaurus Topics

  • Accuracy
  • Dew Point
  • Errors
  • High Temperature
  • Humidity
  • Hygrometers
  • Moisture
  • Transition Temperature
  • Water Vapor
  • Weather
  • Weather Stations

Readers

  • Atmospheric Science/Meteorology
  • Fluid Dynamics.
  • Geodesy