Re: Dew Formation

[Bob LaMontagne <rlamont@POSTOFFICE.PROVIDENCE.EDU>]

Yes, that cools the surface below the ambient air
temperature - eventually approaching the dew point
temperature of the air. But why does condensation occur
preferentially on grass blades?

Bob at PC

*********** REPLY SEPARATOR  ***********

On 3/13/2004 at 11:04 AM John Mallinckrodt wrote:

> > When dew forms on clear nights, it will heavily wet lawns
but will
> > hardly ever leave visible moisture on concrete walkways
or asphalt
> > roads. There are many factors that regulate condensation:
> > temperature, available condensation nucleii, curvature,
hydrophilic
> > surfaces, etc. - but I am having difficulty identifying
the  primary
> > one in this case. Any ideas out there?
>
> The primary mechanism is radiation exchange with 2 pi
steradians of a
> 3 kelvin blackbody plus high resistance thermal conduction
pathways
> to the ground and the (still) air.
>
> --
> John Mallinckrodt        mailto:ajm@csupomona.edu
> Cal Poly Pomona          http://www.csupomona.edu/~ajm
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