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Name: Manny H.
Status: other
Age:  60s
Location: N/A
Country: N/A
Date: 2000-2001

Please provide me with conversion data from frost point to dew point up to -75C. I would like to get a conversion formula or equation from frost point to dew point. Below a freezing point of water, 0C, the dew point is measured with frost point. To convert from frost point to dew point, what formula do you use? If not using a formula, I want to know the data from 0 CA to -75 CA in interval of 5 CA.


I do not know of an equation to convert from frost point to dew point. The accurate computation for dewpoint is difficult (using ambient vapor pressure over water) in a polynomial or series of equations. Computation of frost point using vapor pressure over ice (measured with a frost point hygrometer, chilled mirror type sensor) is more difficult and I don't even know of an equation to do this.

The equations to perform the calculations are beyond the scope of this web page. I think that it would be best to contact a professor of meteorology or researcher directly, or the Smithsonian Meteorological Tables, to obtain the information.

David R. Cook
Atmospheric Section
Environmental Research Division
Argonne National Laboratory

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