How can I calculate the vapor pressure deficit (VPD) using temperature and relative humidity?

To calculate the vapor pressure deficit (VPD), subtract the vapor pressure of the air at the current temperature from the saturated vapor pressure at that temperature, then multiply by the relative humidity as a decimal. The formula is: VPD (1 - RH) (es - ea), where VPD is the vapor pressure deficit, RH is the relative humidity, es is the saturated vapor pressure at the current temperature, and ea is the vapor pressure of the air at that temperature.