Vapour-pressure deficit

Common card · No. 451631

Vapour pressure-deficit, or VPD, is the difference (deficit) between the amount of moisture in the air and how much moisture the air can hold when it is saturated. In equation form: V P D = e s ( T a ) − e a {\displaystyle VPD=e_{s}(T_{a})-e_{a}} e a {\displaystyle e_{a}} = actual vapor pressure e s ( T a ) {\displaystyle e_{s}(T_{a})} = saturation vapor pressure at temperature Ta Once air becomes saturated, water will condense to form clouds, dew...

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