How does hoarfrost form in the morning?

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Hoarfrost forms in the morning when water vapor in the air sublimates directly into ice at temperatures below freezing. This phenomenon occurs despite atmospheric pressure because the air can become supersaturated with moisture, allowing sublimation to happen. The process may involve a combination of sublimation and condensation, where water vapor transitions to ice without becoming liquid. The dew point near surfaces like leaves can drop, facilitating the formation of hoarfrost. Understanding these mechanisms highlights the complex interactions between temperature, pressure, and humidity in atmospheric conditions.
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I was wondering how it comes that we have hoarfrost in the morning. Water has his tripplepoint at 0.001°C and 10³Pa, so subblimation occurs at lower pressure and temperature. But we have atmospherical pressure of 10^5Pa, so how comes we have hoarfrost?

http://www.lsbu.ac.uk/water/phase.html

I think it has something to do with partial pressure (Law of Dalton), but I'm not sure how...
 
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I could be wrong about the technicalities, but when I have seen hoarfrost(an otherwordly, beautiful site, eh?)on trees, shrubbery, fences, etc... I was under the impression that the primary mechanism involved(other than freezing temps)was supersaturated air.
Any insight?
 
So no one knows why water sublimates at this pressure?
 
Is hoarfrost formed by (reverse) sublimation? Maybe it's only a special kind of condensation, folowed by freezing? What is the dewpoint right next to the leaves or whatever where the hoarfrost forms?
 
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