Cloud Droplet Growth by Condensation

  • Consider pure water in equilibrium with air above it -->
  • then the RH = 100%
  • evaporation = condensation
  • vapor pressure (e) = saturation vapor pressure (es)
  • if evaporation > condensation, water is ANSWER

  • if evaporation < condensation, water is ANSWER

  • Now, a droplet surface is not flat as shown to the right -> instead, it has curvature.....

  • Q: how does curvature affect the evaporation/condensation process???